Datasets:

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jxm

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nomic_embed_supervised

like 2

[ "Long rectangular quads? Or neat squarish quads with tris? For curved meshes I've often noticed that in my desperation to avoid tris, I tend to extrude the mesh in a way which creates these long rectangular quads: In this case at least, the mesh is all quads, however the edge flow causes loopcutting to be awkward in some places: I tried creating the same mesh with more even topology, however I found tris unavoidable. Maybe it was because I was starting with the long-quad mesh, but I also found myself using the knife tool for everything.. This makes loopcuts less necessary and easier to place in most cases, though the occasional tri does get in the way. An annoying thing about the tris are the poles, though they aren't too noticeable in this particular case. Both techniques seems to have their advantages and their disadvantages: Which is considered \"better\", if any? Are there any better workflows for creating even topology with as few tris as possible? Or is there some trick I'm missing altogether?", "How to understand \"with\" in the following sentence? Not every job will end up with a success. What is the meaning of \"with\" here? Why not use other preposition? Could native speakers please describe the scene of this sentence for me? Thx.", "Java: Why does if statement never resolve to true?", "What order should Asimov's Foundation series be read in?", "Remove windows XP after installing Ubuntu", "This question led to a new package: I'm trying to make some good-looking numbers in a circle, using the simple command: \\textcircled{1} However, the circle is misaligned vertically with the number, and look a bit sloppy: Any suggestions how can I adjust the vertical alignment so that the numbers look more centered w.r.t to the circles? Or, if that's not an option, what other ways to achieve the same results are possible? I will use those only for numbers, and in very few places, so manual adjustment per glyph is an option. I'm using pdfLaTeX with Computer Modern, if that matters.", "preventDefault() on an tag", "Making ArcPy interactive?", "How to fix missing characters from font after awakening from suspend? I find that often after awakening from suspend on Ubuntu GNOME 16.04 with GNOME 3.20 (I have only found this issue on the latest version, though I have not tried with GNOME 3.18 on 16.04) that I get this strange font issue which can't be fixed by restarting gnome-shell and seemingly only by restarting my entire machine: I do not believe that this is a theme issue as I have tried all the built-in themes (including the dark and light versions) and it is the same for them all. Though it does not seem to affect gnome-shell areas, that is the top-bar, the Activities Overview, etc, are not affected for some reason. So what could this issue be caused by and how can I fix or workaround it? Information Update: I have had a look at but the only options in the gnome-tweak-tool for Antialiasing are Rgba, None, and Grayscale, but none of them seem to have any affect on the issue. Is there something I'm missing?", "Quantum entanglement for faster-than-light (FTL) network communication? Quantum entanglement is 2 atoms that are paired together and when you stop one from spinning the other also stops with the same spin. Can you use these pairs to have faster-than-light (FTL) communication between 2 computers?", "NOTE: Signing up or Logging in via OpenID is no longer officially supported from any of our sites. Currently, is still on the internet, but we are in the process of completely removing it. Stack Overflow was an early and strong supporter of . We built our sign up/log in flow around it. We were idealistic and had , but these hopes weren't realized. Over the years people have wondered if is . We've had to remove support as OpenID providers or . The time has come to part ways. The reality is OpenID support has created a ton of complexity in our codebase and the number of users actively using OpenID simply don't justify that cost. Users have spoken with their actions. You prefer Google, Facebook and Stack Exchange (aka email/PW) based account auth. Of our 9,813,747 accounts around one-tenth of a percent are actively using OpenID (defined as having visited a site in the past 12 months). If you include all the inactive accounts it is still less than 2.9% of all accounts. So, what is the plan? DONE - Remove the ability to create a new account with most OpenID providers DONE - Add the ability to DONE - Convert Launchpad (used on ) to OAuth DONE - Remove creating new accounts with Steam from (Steam removed support for OAuth. Only 454 accounts that use Steam have visited Arqade in the past 6 months.) DONE - We will email all users that rely on deprecated OpenID credentials and request that they DONE - Run an announcement banner for any user who signs in with deprecated OpenID credentials urging them to DONE - End support for logging in via OpenID In progress - Remove (note: only 0.2% of authorized sites in the last year have been non-Stack Exchange sites.) Obviously, if your account relies on OpenID, then make life easy and go now and . If you've forgotten what you credentials you use to login, then to refresh your memory. If you don't see one of the three account types shown in the image below (Google, Facebook or Stack Exchange) then click the \"add more logins\" button to add one of them to your account. Remember, SE OpenID accounts are really email/pw accounts handled through complicated OpenID code path. They will be migrated to a simpler email/pw only code path as a part of this change. No extra work required on your part.", "How do I disable Dunst and go back to notify-osd? I installed i3, which recommends dunst, but I'm not using i3 at the moment, and the dunst notifications don't really fit with Unity. I'd rather not uninstall dunst totally, since I might want to start using it at some point in the future; is there a way to switch back to notify-osd without uninstalling dunst?", "Blender 2.8 - AWS EC2 command line EEVEE render I have been trying to get this to work for a couple days now. I have an EC2 P2 instance with NVIDIA CUDA configured by default, its a Deep learning Ubuntu AMI. This OS does not have a GUI so everything is via terminal. I downloaded Blender's 2.8 TAR file for Linux and set it up on the EC2 instance. And ran the following command from the directory where the TAR file is extracted: ./blender -b -noaudio /home/ubuntu/file.blend --render-output . --engine BLENDER_EEVEE --render-format PNG --verbose 4 All I see in the output is this: Blender 2.80 (sub 75) (hash f6cb5f54494e built 2019-07-29 17:17:04) found bundled python: /mnt/blender/blender-2.80-linux-glibc217- x86_64/2.80/python Read blend: /home/ubuntu/file.blend Blender quit Don't know why its quitting but I am unable to debug this any further. Any help would be appreciated. UPDATE: As per @rjg's recommendation, ran the following command: ./blender -b -noaudio /home/ubuntu/file.blend --render-output . --engine BLENDER_EEVEE --render-format PNG -f 1 --verbose 4 Got the following error: Blender 2.80 (sub 75) (hash f6cb5f54494e built 2019-07-29 17:17:04) found bundled python: /home/ubuntu/blender/blender-2.80-linux-glibc217- x86_64/2.80/python Read blend: /home/ubuntu/file.blend Unable to open a display Aborted (core dumped)", "A matrix inside a table Possible Duplicate: I am trying to insert a matrix inside a table, and I am looking for a good way to do this. Usually when I write matrices in equations, I use array environment, so I naively defined an array inside tabular, and it sort of works. The only problem is that the matrix itself seems to take up a huge amount of space inside the cell. An example is \\begin{tabular}{|c|c|} \\hline \\textbf{EKF} & \\textbf{UKF}\\\\ \\hline $Q = \\left[ \\begin{array}{cc} 0.1 & 0 \\\\ 0 & 0.1 \\end{array}\\right]$ & $Q = left[ \\begin{array}{cc} 0.01 & 0 \\\\ 0 & 0.01 \\end{array}\\right]$\\\\ \\hline $R = 5 \\times 10^{-3}$ & $R = 5 \\times 10^{-5}$ \\\\ \\hline \\end{tabular} Is there any way to increase the spacing in the cell containing the matrix without that matrix taking up all the space?", "Dates and times: \"on\", \"in\", \"at\"? I’m often confused when I speak about times and dates. What is the rule for using on, in, and at in the following sentences? I will do it ___ Tuesday. We married ___ March. He returned ___ the same day. Every day ___ the same time, I walk the dog.", "$L^p$ integrable but not $L^q$ integrable", "Activate Rigid Body Physics at certain time? I've been trying to make a wrecking ball smash through a figure of sorts, not really sure what exactly but I made an example. The problem I'm having is that the figure does indeed fall apart, but I would like it to stay put together until the ball hits it. I achieved this by using Cell Fracture on the figure and just using Rigid Body. Again, I just need a way for the figure to stay still until hit by the ball, and then have all of its pieces come apart.", "Another point of view that $\\mathbb{Z}/m\\mathbb{Z} \\times\\mathbb{Z}/n\\mathbb{Z}$ is cyclic. I was thinking that the product of groups $\\mathbb{Z}/2\\mathbb{Z} \\times\\mathbb{Z}/2\\mathbb{Z}$ is not cyclic, but $\\mathbb{Z}/2\\mathbb{Z} \\times\\mathbb{Z}/p\\mathbb{Z}$ is cyclic if p is an odd prime. Then I found logic that $\\mathbb{Z}/m\\mathbb{Z} \\times\\mathbb{Z}/n\\mathbb{Z}$ is certainly cyclic if $m$ and $n$ are coprimes. I searched on google a proof of that, to compare with mine and the answer is that $\\mathbb{Z}/m\\mathbb{Z} \\times\\mathbb{Z}/n\\mathbb{Z}$ is isomorphic to $\\mathbb{Z}/mn\\mathbb{Z}$ (which is clearly cyclic) $\\iff$ $m$ and $n$ are coprimes. But I got another proof and I want to know what you think about it : I claim that $([1]_m,[1]_n)$ generates $\\mathbb{Z}/m\\mathbb{Z}$ $\\times\\mathbb{Z}/n\\mathbb{Z}$, where $[a]_d$ is the canonical projection of $a\\in \\mathbb{Z}$ into $\\mathbb{Z}/d\\mathbb{Z}$. Let's take multiples of $([1]_m,[1]_n)$ until we get $m \\cdot$ $([1]_m,[1]_n) = ([0]_m,[m]_n)$ (where I suppose $m=\\min(m,n)$... otherwise, consider $\\mathbb{Z}/n\\mathbb{Z}$ $\\times\\mathbb{Z}/m\\mathbb{Z}$ and $\\min(m,n)=n$). The next step is $([1]_m,[m+1]_n)$. This pair is not equal to $([1]_m,[1]_n)$, since $m+1 \\not\\equiv1$ mod $n$ ($m$ and $n$ are supposed to be coprimes). We can now continue adding $([1]_m,[1]_n)$ to the results. The last step is precisely reached when you got $([mn]_m,[mn]_n)=([0]_m,[0]_n)$. At this point, the fact that $m$ and $n$ are coprimes is absolutely necessary because if they are not coprimes, $lcm(m,n)\\ne m\\cdot n$ and $([lcm(m,n)]_m,[lcm(m,n)]_n)=([0]_m,[0]_n)$ but all the $m \\cdot n$ possible pairs are not reached, only the $lcm(m,n)$ are !", "How to indent subsection in AMS TOC I used AMS LaTeX template with gsm-l package to write my teacher's book. The table of content that produced has the following form: in which 1, 2, 3.... are sections and 3.1, 3.2, 4.1, 4.2,.... are the subsection. I want to indent the subsection with respect to the section, like this (it's ok without dots, though):", "How can I force a line break in the table of contents?" ]

[ "Execute an installed Python package as a script?", "What is the limit of $n \\sin (2 \\pi \\cdot e \\cdot n!)$ as $n$ goes to infinity?", "Convert Month Number to Month Name Function in SQL I have months stored in SQL Server as 1,2,3,4,...12. I would like to display them as January,February etc. Is there a function in SQL Server like MonthName(1) = January? I am trying to avoid a CASE statement, if possible.", "Background: I have the opportunity to pursue a Computer Science graduate degree at a well respected program (around top 20). I spoke with the professors at the university and I feel like I am a good fit with their research program. My ultimate pursuits are to complete a PhD in CS. I've done research as an undergraduate and it has only confirmed my notion that I want to pursue a research track career. More background: I applied to jobs (in case I was rejected to all the programs I applied for) prior to hearing back from my respective graduate programs. I accepted a position for an industry job (this was to secure I wouldn't be both unemployed &amp; not in school). Dilemma: Turns out my top graduate school is very interested in me, and I'm very interested in them. I would rather go to graduate school than work in industry forever. The industry job pays very well. I am split between A) working for a maximum of 1 year(It would only be 1 year, seriously I do not care about the money enough to work past a year) and B) going straight to graduate school. My concerns are as follows, if I choose A): Could I potentially defer my admissions? If I am not allowed to defer my admissions, would I have a good chance of re-applying and being accepted a year later? Would my potential advisers look down on me for deciding to work a year? I already made my mind up it would be a 1 year gig if I decide A). I know some people say once you make money, you may not be able to readjust to the graduate salary pay. But I don't think that will apply to because I'm going to live very frugally with or without industry pay.", "How to make many copies of similar graphs systematically? I want to make various copies of a graph in tikz. The graph I want has 10 vertices. But only has the edges between the vertices a_i,a_(i+1),t,b. I would like to automatically create 8 copies of this graph. and draw them. I just don't know how to code it. Here is my current code, but it adds all of the edges to the same copy of the graph: \\begin{tikzpicture} [main_node/.style={circle,fill=blue!20,draw,minimum size=2em,inner sep=3pt]}] \\node[main_node] (8) at (0:0.5) {b}; \\node[main_node] (9) at (180:0.5) {t}; \\foreach \\x in {0,1,...,7} \\node[main_node] (\\x) at (360/8*\\x:2) {$a_{\\x}$}; \\foreach \\x in {0,1,...,7}{ \\pgfmathsetmacro{\\y}{int(mod(\\x+1,8))} \\path[draw,thick] (\\x) edge node {} (8); \\path[draw,thick] (\\x) edge node {} (9); \\path[draw,thick] (\\x) edge node {} (\\y); \\path[draw,thick] (8) edge node {} (9); \\path[draw,thick] (8) edge node {} (\\y); \\path[draw,thick] (9) edge node {} (\\y); } I want each of the edge sets to be drawn seperately.", "Freeman and Tukey interval If $Y$ is Poisson$(\\lambda)$ distributed, how do we obtain this confidence interval for $\\lambda$: $$ \\left (\\frac{(\\sqrt Y+\\sqrt{Y + 1}-z_{(α⁄2)} )^2 - 1}{4},\\ \\frac{(\\sqrt Y+\\sqrt{Y +1}+z_{(α⁄2)} )^2 - 1}{4} \\right ) $$", "Prove that $x^{2} \\equiv -1 \\pmod p$ has no solutions if prime $p \\equiv 3 \\pmod 4$.", "Suppose $f(x)$ and $g(x)$ are continuous function from $[0,1]\\rightarrow [0,1]$, and $f$ is monotone increasing, then how to prove the following inequality: $$\\int_{0}^{1}f(g(x))dx\\le\\int_{0}^{1}f(x)dx+\\int_{0}^{1}g(x)dx$$", "Uk tourist visa - duration of stay My mother is given a UK tourist visa for 2 years with a duration of stay as 180 days. It is a c type multiple entry visa. Is this 180 days is the total stay she can take or is it duration of stay per visit. Thanks in advance for your reply.", "How to prove this inequality $\\left|x\\sin{\\frac{1}{x}}-y\\sin{\\frac{1}{y}}\\right|<2\\sqrt{|x-y|}$? For any real numbers $x,y\\neq 0$,show that $$\\left|x\\sin{\\dfrac{1}{x}}-y\\sin{\\dfrac{1}{y}}\\right|&lt;2\\sqrt{|x-y|}$$ I found this problem when I dealt with . But I can't prove it. Maybe the constant $2$ on the right hand side can be replaced by the better constant $\\sqrt{2}$? Thank you.", "Getting secondary citations right I have some questions regarding secondary citations (in an computer-science research paper that should be published in a journal). I know that they should be avoided when possible, but it is not always that easy. More specifically, my situation is this: Article A says: The average value of ... in ... is ... [B]. [C]’s study says that in ... the value is ... This statement is exactly what i need for my paper. If I read [B] and [C], I see that [A] cited them correctly and if I would have found these two other articles myself, I would have written the same. Now how to cite this in a correct way? [B] and [C] say (cited in [A]) ... and do a “bad” secondary quote; [B] and [C] say ... and neglect the investigation done by [A] and peform citation plagiarism; [A] says ... and neglect that the data was the achievement of [B] and [C]. [A] says based on the findings of [B] and [C] ... and do a secondary quote again.", "How to combine paths in Java? Is there a Java equivalent for in C#/.NET? Or any code to accomplish this? This static method combines one or more strings into a path.", "What does the phrase \"Underfull \\hbox (badness 10000) in paragraph\" actually mean? What does the actual phrase above mean?", "How do you make the camera in blender cycles render everything so it looks like pixels? I want everything in my scene to look pixelly like this image I found:", "Adaline is 100-something years old, and her daughter appears to be 90 years old. Well, Adaline gave birth to her in her mid 20's, and to be precise, she should be 80. Anyways, Adaline's old lover's son (Ellis) is probably in his late 20's/early 30's. And Adaline has stopped aging at 29, which is pretty close to Ellis. Her old lover is said to be a few years younger than her and still, his son is so young. Also, Adaline could make him believe that she is the daughter of her own old self. Then, how can Adaline's real life daughter be so old? I can't make sense out of this. Why is it this way? The age pattern of the actors and actresses is inconsistent. It seems to me that the filmmakers have exaggerated some things.", "Is there a clear set of conditions under which lasso, ridge, or elastic net solution paths are monotone? The question demonstrates solution paths for the lasso estimator that are not monotonic. That is, some of the cofficients grow in absolute value before they shrink. I've applied these models to several different kinds of data sets and never seen this behavior \"in the wild,\" and until today had assumed that they were always monotonic. Is there a clear set of conditions under which the solution paths are guaranteed to be monotone? Does it affect the interpretation of the results if the paths change direction?", "Expectation of momentum in the bound state Is it logically correct to assert that the expectation of the momentum $$\\langle \\hat p \\rangle=0$$ for any bound state because it is bound to some finite region? What is the physical interpretation of the fact that $$\\langle \\hat p \\rangle=0$$ in an energy eigenstate $\\psi_n(x,t)$ but $$\\langle \\hat p \\rangle\\neq0$$ in some superposition state $$\\psi(x,t)=c_m\\psi_m(x,t)+c_n\\psi_n(x,t)~?$$ Here $\\psi_n(x,t)$ the eigenstates of the Hamiltonian, for example, in the problem of particle in a box (say).", "Usage of \"but\" in a sentence. I'm reading Robinson Crusoe and came across many of these constructions with \"but\" in it. I can't help but thought they were a little unusual. I don't consider myself fluent in English, that's why I ask. Here is an example: This I saw no remedy for but by making an enclosure about it with a hedge; which I did with a great deal of toil, and more, because it required speed. Second one: However, as my arable land was but small, suited to my crop, I got it totally well fenced in about three weeks' time; By typing the second out I figured it is actually the normal textbook case of \"but\", just an, in my opinion, screwed ordering in the sentence. Is this what it means? However, as my arable land was suited to my crop but small, I got it totally well fenced in about three weeks time; Why did the author do this? Can you comment on the first sentence too? It's not a textbook-but-usage as I see it.", "How can I cast int to enum?", "Question about Subrings and integraly closed" ]

[ "Base-b Representation of an Integer: Why can I make the assumption about number of terms in expansions in uniqueness part? Reading the book of Koshy I have come across the below theorem. It states that I can write any integer $N$ in a base $b\\ge2$ representation $N=a_kb^k+...+a_1b+a_0$ such that $0\\le a_i&lt;b$, $a_k \\neq 0$ for some $k\\ge0$. In the uniqueness part, why can I assume the expansions contains the same number of terms ? I must prove that all expansions of $N$ equal the one in the theorem, but if I add terms to the expansion by zero coefficients, well, then the expansion is not in the proper form anymore ? (the greatest term in the expansion is $0$ if I add zero coefficients) . Can someone help clear this out ? Why can I assume the expansions contain the same number of terms ? If I add terms to the expansion, well then I've violated the form of the expansion ?", "Let $s_n$ be a sequence defined as given below for $n \\geq 1$. Then find out $\\lim\\limits_{n \\to \\infty} s_n$. \\begin{align} s_n = \\int\\limits_0^1 \\frac{nx^{n-1}}{1+x} dx \\end{align} I have written a solution of my own, but I would like to know it is completely correct, and also I would like if people post more alternative solutions.", "Can I travel to Dublin, Republic of Ireland with UK Tier 2/Schengen visas with Indian Passport", "Registry key / GPO to disable and block Windows 10 upgrade?", "Petersen graph is not a Cayley graph How can I show that the Petersen graph is not a Cayley graph? I don't know very much about Cayley graphs, I know that they are vertex-transitive, but so is the Petersen graph. It probably has to do with the group structure of $\\Gamma$ in $Cay(\\Gamma,S)$ (which is a group of order $10$, i.e., it is either the cyclic group $C_{10}$ or the dihedral group $D_{10}$). Then I am guessing we go for some sort of contradiction(?). My group theory is a bit rusty, I would very much appreciate someone showing me how to do this one!", "I want to do research but I'm too old for a PHD I really love research. I started a research project in graduate school for my M.A. in English. My research topic is a very viable and interesting topic for a dissertation. I'll be 60 on my next birthday and I know that many Ph.D programs are traditionally geared toward younger students.I was wondering are there any programs that I can continue this research in without facing the issues of ageism in academia?", "Show that if terms of a series have ratio less than the ratio of convergent series, then the series converges We have two infinite series $\\sum a_n $ and $\\sum b_n$, such that $a_n &gt; 0,\\ b_n &gt; 0$ and $a_{n + 1}/a_n \\leq b_{n + 1}/b_n$ for all $n$. Show that if $\\sum b_n$ converges, then $\\sum a_n$ also converges. Any hints on how to prove this? I can sort of picture why this must be true, but I'm not sure how to prove this rigorously. I'm not sure using the ratio test would help here..", "After update to OS X 10.11 I started having these bugs: Finder sidebar text flashing Very high CPU load: I have Macbook Pro Retina 13\" Mid 2014 I reset NVRAM. I deleted com.apple.finder.plist, it didn't help. Also I did this: , no longer flashes.", "Salutation for two doctors (not married)", "Are objects in PHP passed by value or reference?", "Does the std::stack in the C++ STL expose any iterators of the underlying container or should I use that container directly?", "What is ISCAS85 benchmark? What is ISCAS85 benchmark? I find it in a , is there any simulator for it?", "Split string every nth character?", "Let $G$ be a lie group with lie algebra $\\frak{g}$. Let $Aut(\\frak g)$ be the automorphism group of $\\frak{g}$. Its clear to me that $Aut(\\frak{g})$ $\\subset GL(\\frak{g})$ since any automorphism of $\\frak{g}$ is also a linear transformation. Now i have several questions: How do i prove that $Aut(\\frak{g})$ is actually a lie subgroup of $GL(\\frak{g})$? I've tried playing with actions to realize $Aut(\\frak g)$ as an orbit or an isotropy subgroup but nothing worked out... Say $H \\subset G$ is an abstract subgroup (not necessarily lie). Are the following statements equivalent? $$\\{T_e H \\text{ is closed under the lie bracket of } \\frak{g} \\}$$ $$ \\{H \\text{is a lie subgroup of } G\\}$$ How does the lie algebra of $Aut(\\frak g)$ look like? When does $Aut(\\frak g)$ $= G$? what does $Aut(\\frak g)$ tell me about $G$?", "I was trying to give the wording \"isomorphic groups have the same structure\" a precise interpretation, at least for the finite order case. A positive answer to my final question would reach the goal, as it would translate a \"$\\cong$\" between groups into a \"$=$\" between sets. For $n$ positive integer, let be: $I_n:=\\{1,\\dots,n\\}$; $G$, $\\overline G$ groups of order $n$; $\\psi\\colon G \\rightarrow \\overline G$ isomorphism; $f$, $\\bar f$ bijections; $\\theta$, $\\bar \\theta$ embeddings; in general, $\\varphi^{(\\alpha)}$ the isomorphism between symmetric groups on sets of the same cardinality, defined by $\\sigma \\mapsto (g \\mapsto (\\alpha\\sigma\\alpha^{-1})(g))$, where $\\alpha$ is a bijection between the sets; $S_n$ the symmetric group of degree $n$. Visually: $$ \\newcommand{\\ra}[1]{\\kern-1.5ex\\xrightarrow{\\ \\ #1\\ \\ }\\phantom{}\\kern-1.5ex} \\newcommand{\\ras}[1]{\\kern-1.5ex\\xrightarrow{\\ \\ \\smash{#1}\\ \\ }\\phantom{}\\kern-1.5ex} \\newcommand{\\da}[1]{\\bigg\\downarrow\\raise.5ex\\rlap{\\scriptstyle#1}} \\begin{array}{c} I_n &amp; &amp; I_n \\\\ \\da{f} &amp; &amp; \\da{\\bar f} \\\\ G &amp; \\ras{\\psi} &amp; \\overline G \\\\ \\da{\\theta} &amp; &amp; \\da{\\bar \\theta} \\\\ \\operatorname{Sym}(G) &amp; \\ras{\\varphi^{(\\psi)}} &amp; \\operatorname{Sym}(\\overline G) \\\\ \\da{\\varphi^{(f)}} &amp; &amp; \\da{\\varphi^{(\\bar f)}} \\\\ S_n &amp; &amp; S_n \\\\ \\end{array} $$ Is it $(\\varphi^{(f)}\\circ\\theta)(G)=(\\varphi^{(\\bar f)}\\circ\\bar \\theta)(\\overline G)$?", "“He is small enough to walk.” But baby wasn't walking so why didn't they use “small” instead of “small enough”?", "How to unlock gungeoneers", "How can I take a photo with everything in focus with my DSLR? I am quite new to DSLRs and one of the first things I noticed was the incredible focus points and appearance of depth that you can achieve. That is great in a lot of scenarios, but not in all. When filming a landscape as a whole, I do not want to have the focus on that single tree, but on the whole skyline. Is there a way by which you can sort-of \"disable\" the focus, so that the raw image is recorded without any added blur? I suppose something as simple as this is only a small function you can turn off, but I can't seem to find it in the manual of my camera.", "Package pgfplots Error: CRITICAL: shader=interp: got unsupported pdf shading type '0' For the set of data , the following code can't compile showing the error Package pgfplots Error: CRITICAL: shader=interp: got unsupported pdf shading type '0'. This may corrupt your pdf!. \\documentclass[border= 5mm]{standalone} \\usepackage{pgfplots} \\pgfplotsset{compat=newest} \\begin{document} \\begin{tikzpicture} \\begin{axis}[unbounded coords=jump, view={70}{40}] \\addplot3 [surf,shader=interp] table [x index={0}, y index={1}, col sep=tab] {mySurfaceData.txt}; \\end{axis} \\end{tikzpicture} \\end{document} So, what went wrong to cause this? P.S. the original data without NaN is available , where I would like to skip plotting those points of z=1.", "What's the difference between lists and tuples? What's the difference? What are the advantages / disadvantages of tuples / lists?" ]

[ "A commercial airport being any airport that has regular scheduled passenger flights. The mathematics of got me thinking: is the network of scheduled flights a connected graph? That is, is there a pair (or triplet or even larger set) of airports such that they only have scheduled flights with each other? Or can you get from any airport to any other? Ignore vagaries like cargo and general aviation. I'm looking for two airports that I can shuttle between, but would have to drive (or sail) to get to one or the other of them.", "Prove that $$\\sum^{n}_{i=1}\\binom{n}{i}i=n2^{n-1}$$ I can't find counting interpretations for either of the sides. A hint of \"if $S$ is a subset of $\\{1, . . . , n\\}$ and $S^\\prime$ is its complement then $|S| + |S^\\prime| = n$\" was also given, but I still don't know how to begin.", "Integral $\\int\\!\\sqrt{\\cot x}\\,dx $", "I have an Ubuntu 14.04 server that has no external monitor connected. I use NoMachine to remote control the machine. When I do so, the Unity/Gnome interface doesn't see any monitors connected, so I can only use 800x600 when connecting with NoMachine. If I plug in a monitor, I can set the resolution to whatever size the NoMachine window is on the remote computer. Is there a way to create a \"fake\" monitor device on Ubuntu so I can set a desktop resolution in Unity/Gnome?", "Moving files of specific type/extension from one directory to another?", "How to create meaningful relationships with NPCs How do I help the PCs to create meaningful relationships with NPCs? Maybe it is a result of my group playing too many one-dimensional adventures trying to find whatever MacGuffin they are after each week, but most of the time my PCs don't tend to value NPCs too much. Every time they meet an NPC they quickly evaluate what immediate values the NPC can give or tend to ignore them. What I would really like is to have some good relationships where the PCs actually go out of their way to help NPCs without selfish motivation or even just to try to think of NPCs more and how their actions affect others. I am not looking for a specific game rules solution to this, but instead techniques to get the players to feel attachment to these fictional characters.", "In terms of UX what do you guys think is the best approach when integrating a trial period for subscriptions? My application offers a 15 day trial, at the minute the user can sign up without providing any payment information (Paypal Subscription). The account is then set to trial status and after 15 days the user will be redirected to an upgrade page. Do you think this is the best approach? I am unsure whether or not to let Paypal manage the trial, this however means that the user will need to go through the Paypal payment system during signup. I think this may put some people off signing up. On the other hand this approach may increase the number of conversions to a full account.", "Does DTIME(O(n)) = REGULAR? (I don't think that this is a good fit on cstheory, since I figure that this question already has a known answer. However, if you think that this would be a better fit there, please feel free to migrate it) It can easily be shown that REGULAR (the class of regular languages) is contained in DTIME(O(n)), because for any regular language L we can decide membership in that language in O(n) time by converting a DFA that decides L into a TM that decides L in a single pass over the input. However, is it also true that DTIME(O(n)) is contained in REGULAR; that is, that any language that can be decided in O(n) time by a single-tape TM is necessarily regular? I have no idea how to approach this problem, and every language I can think of in DTIME(O(n)) seems to be regular. Intuitively, this would make sense, since if you're only allowed to make finitely many passes over the input, you could only remember finitely many things about it, which it seems like you could simulate with a sufficiently large DFA. However, the fact that you can write to the input tape seems like it might complicate things. And no, this isn't a homework problem. I'm actually teaching a course that covers computability and complexity theory and thought it would be interesting to present the answer to this question in lecture. :-) Thanks!", "How do I get an animated gif to work in WPF? What control type should I use - Image, MediaElement, etc.?", "Set root domain record to be a CNAME I need to create an NS record for a domain that is a CNAME, for the purpose of having two domains pointed at one IP, and not having to maintain the current IP address in two different places. The DNS provider for this domain is DynDNS, but they block this operation: CNAME cannot be created with label that is equal to zone name I can do this with another domain whose DNS is served by 1and1: root@srv-ubuntu:~# dig myseconddomain.co.uk ; &lt;&lt;&gt;&gt; DiG 9.4.2-P1 &lt;&lt;&gt;&gt; myseconddomain.co.uk ;; global options: printcmd ;; Got answer: ;; -&gt;&gt;HEADER&lt;&lt;- opcode: QUERY, status: NOERROR, id: 61795 ;; flags: qr rd ra; QUERY: 1, ANSWER: 2, AUTHORITY: 0, ADDITIONAL: 0 ;; QUESTION SECTION: ;myseconddomain.co.uk. IN A ;; ANSWER SECTION: myseconddomain.co.uk. 71605 IN CNAME myfirstdomain.co.uk. myfirstdomain.co.uk. 59 IN A www.xxx.yyy.zzz ;; Query time: 298 msec ;; SERVER: 10.0.0.10#53(10.0.0.10) ;; WHEN: Tue Aug 18 14:17:26 2009 ;; MSG SIZE rcvd: 78 Is this a breach of the RFCs or does DynDNS have a legitimate reason for blocking this action? Followup Thanks to the two answers already posted I now know that 1and1 IS breaching RFCs to do this. However it does work and they seem to support it. For a company that hosts so many domains it seems very odd that they get away with doing this on such a massive scale without objection. More followup The output of \"dig myseconddomain.co.uk ns\" as requested. root@srv-ubuntu:~# dig myseconddomain.co.uk ns ; &lt;&lt;&gt;&gt; DiG 9.4.2-P1 &lt;&lt;&gt;&gt; myseconddomain.co.uk ns ;; global options: printcmd ;; Got answer: ;; -&gt;&gt;HEADER&lt;&lt;- opcode: QUERY, status: NOERROR, id: 18085 ;; flags: qr rd ra; QUERY: 1, ANSWER: 2, AUTHORITY: 0, ADDITIONAL: 2 ;; QUESTION SECTION: ; myseconddomain.co.uk. IN NS ;; ANSWER SECTION: myseconddomain.co.uk. 4798 IN NS ns67.1and1.co.uk. myseconddomain.co.uk. 4798 IN NS ns68.1and1.co.uk. ;; ADDITIONAL SECTION: ns67.1and1.co.uk. 78798 IN A 195.20.224.201 ns68.1and1.co.uk. 86400 IN A 212.227.123.89 ;; Query time: 59 msec ;; SERVER: 10.0.0.10#53(10.0.0.10) ;; WHEN: Wed Aug 19 12:54:58 2009 ;; MSG SIZE rcvd: 111", "How do I share a private YouTube video with someone? I have uploaded a YouTube video and marked it as private. Now I want to share it with someone. I have tried to share it a few times, but they have not received any email notification. What is the proper way of sharing the video?", "My prof gave us this definition of an Echelon system: A system of m linear equations in n variables is called an echelon system if m ≤ n. Every variable is the leading variable of at most one equation. Every leading variable is to the left of the leading variables of all lower equations. Every equation has a leading variable. I don't understand this definition at all. Q1)If you have this system of equations: $ax_1 + bx_2 + cx_3 = z$ $dx_1 + ex_2 + fx_3 = z$ its not an echelon system because of multiple equations having the same variable as the leading variable and therefore violating rule #2. But if you switch around variables and rewrite the equation as: $ax_1 + bx_2 + cx_3 = z$ $ex_2 + dx_1 + fx_3 = z$ It becomes an echelon system! Why would the way you write a system of equations affect its definition? Q2)Why would point number three matter? Can't you just move around the equations so that they are in order of variables? Q3)Why would point number four matter? If you have a equation in the system that doesn't have a leading variable can't you just disregard it? For example if you have the equation $0x = 0$ in the equation can't you just ignore it to have a echelon system since it doesn't affect the solution of the system?", "\"The ticket is printing\" vs \"...is being printed\" You're standing in front of a ticket vending machine and it says \"The ticket is printing\". Is that correct or should it be \"The ticket is being printed\"? EDIT: If both are correct, which one should be preferred or is more common?", "How do I convert my PhD dissertation so that it can be published as a book?", "Generalized Tube Lemma", "I had the following two problems: Find a counterexample for $f_*(A \\cap B) \\supseteq f_*(A) \\cap f_*(B)$ and $ f_*(A-B) \\subseteq f_*(A) -f_*(B).$ Where $f_*(X)$ is the image of $X$ under $f$ for some function $f:A \\rightarrow B $ and some subset $X \\subseteq A$. I came with the following answer: Let $ f: \\mathbb{Z} \\rightarrow \\mathbb{Z} $, where $f: x\\mapsto 0$; let $A=\\{1,2\\}$, and $B=\\{3,4\\}$. For $f_*(A \\cap B) \\supseteq f_*(A) \\cap f_*(B)$, $$ f_*(A \\cap B) = f_*\\{ \\varnothing\\} = \\varnothing \\hspace{1cm} \\text{and} \\hspace{1cm} f_*(A) \\cap f_*(B)=\\{0\\} \\cap \\{0\\} = \\{0\\}. $$ It follows that $ \\varnothing \\nsupseteq \\{0\\} $. For $ f_*(A-B) \\subseteq f_*(A) -f_*(B)$, $$f_*(A-B)=f_*(\\{1,2\\})=\\{0\\} \\hspace{1cm} \\text{and} \\hspace{1cm} f_*(A) - f_*(B) = \\{0\\} - \\{0\\} = \\varnothing$$ It follows that $ \\{0\\} \\nsubseteq \\varnothing $. Now (assuming my answer is correct), let's say I want to find more counterexamples or maybe a more general answer (e.g. all the conditions under which the inclusion fails). Other than by trial and error or just intuition, how would I do that? I know this is a broad question, so I'm specifically asking for methods or advice on how to build counterexamples in elementary set theory (for example, tips on where to begin or rules that apply in general that may be unobvious).", "I have being using Skype for a long time on my Ubuntu 14.04 LTS. From this morning on, Skype simple cannot connect to my account anymore. That is my Skype version: Skype 4.3.0.37 © 2014 Skype and/or Microsoft My Ubuntu system: LSB Version: core-2.0-amd64:core-2.0-noarch:core-3.0-amd64:core-3.0-noarch:core-3.1-amd64:core-3.1-noarch:core-3.2-amd64:core-3.2-noarch:core-4.0-amd64:core-4.0-noarch:core-4.1-amd64:core-4.1-noarch:cxx-3.0-amd64:cxx-3.0-noarch:cxx-3.1-amd64:cxx-3.1-noarch:cxx-3.2-amd64:cxx-3.2-noarch:cxx-4.0-amd64:cxx-4.0-noarch:cxx-4.1-amd64:cxx-4.1-noarch:desktop-3.1-amd64:desktop-3.1-noarch:desktop-3.2-amd64:desktop-3.2-noarch:desktop-4.0-amd64:desktop-4.0-noarch:desktop-4.1-amd64:desktop-4.1-noarch:graphics-2.0-amd64:graphics-2.0-noarch:graphics-3.0-amd64:graphics-3.0-noarch:graphics-3.1-amd64:graphics-3.1-noarch:graphics-3.2-amd64:graphics-3.2-noarch:graphics-4.0-amd64:graphics-4.0-noarch:graphics-4.1-amd64:graphics-4.1-noarch:languages-3.2-amd64:languages-3.2-noarch:languages-4.0-amd64:languages-4.0-noarch:languages-4.1-amd64:languages-4.1-noarch:multimedia-3.2-amd64:multimedia-3.2-noarch:multimedia-4.0-amd64:multimedia-4.0-noarch:multimedia-4.1-amd64:multimedia-4.1-noarch:printing-3.2-amd64:printing-3.2-noarch:printing-4.0-amd64:printing-4.0-noarch:printing-4.1-amd64:printing-4.1-noarch:qt4-3.1-amd64:qt4-3.1-noarch:security-4.0-amd64:security-4.0-noarch:security-4.1-amd64:security-4.1-noarch Distributor ID: Ubuntu Description: Ubuntu 14.04.3 LTS Release: 14.04 Codename: trusty Any suggestion why or how to fix it? Thanks in advance.", "Installing 64-bit geoprocessing of ArcGIS for Desktop? I am trying to install 64-bit processing to ArcGIS 10.2, but the ESRI . One similar question on this exchange that shows an option to include this, but my setup installation program (which I downloaded) does not show this installation window, but instead goes straight to selecting features to install as shown below. I can't find any other documentation for running 64-bit geoprocessing on ArcGIS version 10.2. Can anyone show me how to do this? or is it best to just try to install the service pack 1 version of it?", "How does Fermat's principle make light choose a straight path over a short path? This is a thought experiment where I have made a &quot;C&quot; shaped hole inside diamond. The refractive index $(\\mu)$ of diamond is 2.45. Say we shine a laser from top of the &quot;C&quot; as shown. My calculations show that light reaching A can reach B in the least possible time if gone through the &quot;C&quot;. but I'm pretty sure the perpendicular laser beam travels undeflected and straight down. Though I don't have experimental evidence, I see something wrong either with my intuition or with the theory. It would be great if someone could clarify. * 'a' in the diagram is the thickness of the cutout and all comparable distances can be taken 'a'.", "Are there difference between those sentences? Alex is getting married next month. Alex will get married next month. Seems that the first one is expressed in present continues, and the second on in future tense. Am I correct?" ]

[ "If someone who is otherwise healthy decided to drink fairly heavily and consistently over a long period of time, what is the healthiest way to do so? Example: Stay extra hydrated by drinking more water, take a multivitamin, get more sleep, etc. Obviously the best solution would be to cease drinking, but IF that person is stubborn and won't quit - what's the best way to go about it?", "Why do liquids boil when their vapor pressure equals the ambient pressure? Given that the boiling point of a liquid is the temperature at which the vapor pressure is equal to the ambient (surrounding) pressure, what significance does a liquid's vapor pressure have in the formation of bubbles that happens at and above the boiling point? The definition of boiling point seems to imply that the pressure inside of the bubbles must be at least as great as the liquid's vapor pressure in order to balance the outside pressure, but is there any particular reason why the pressure inside of the bubbles is related to the vapor pressure? The vapor pressure seems to be a measurement describing the tendency of the molecules to escape from the surface of the liquid, but I don't see how that relates to bubble formation within the liquid. This question has bothered me for a while, so any help would be much appreciated.", "Is it possible to play D&D 5e solo? Is it at all possible to run a solo game where you act as the DM/GM for yourself? I know there was a 4th edition adventure published in an old issue of one of the D&amp;D magazines but recently I read somewhere (Reddit I think) that the games Outbreak: Undead and Eclipse phase were good games to play solo. Can anyone with experience with running a game of D&amp;D 5e for themselves explain how to do so?", "Sublime Command not working in SSH server on Ubuntu 14.04?", "A No-Nonsense Introduction to Quantum Field Theory I found Sean Carroll's \"A No Nonsense Introduction to General Relativity\" (about page . pdf ), a 24-page overview of the topic, very helpful for beginning study. It all got me over the hump of learning the meaning of various terms associated with GR, most of which I had heard before without understanding. It also outlined the most important examples. Is there a similar document for quantum field theory, which presents the main equations, briefly describes the main ideas, and summarizes the most important applications and results so that the reader can feel the lay of the land before studying in depth?", "Why is scale factor inversely proprotional to temperature? In all lectures, books and papers I have read about, the scale factor of the universe is inversely proportional to temperature $$a \\propto \\frac{1}{T}$$ What is the reasoning behind this relation? People did mention stretching of wavelength proportional to scale factor and wavelength being inversely proportional to temperature by Wein's law, but somehow this argument doesn't seem convincing to me. How did we initially come about to this relation?", "In how many ways can we choose k items from n distinct items put in a circle. Then further extension of the question, if I want to find out the number of ways to choose k items from n distinct items in a circle such that no 2 are together. Thanks", "In the Law of Reflection, the angle of incidence is equal to angle of reflection. Why is this true? This is clearly true experimentally, but how does one prove this true mathematically?", "In addition to whatever files I may choose to exclude, what files does the system exclude by rule or classification? It might make sense not to backup Trash or Caches, but I'm looking for a way to tell what files are skipped \"behind the scenes.\" Knowing if the system maintains an exclusion list or exclusion pattern would be very helpful in managing larger groups of macs.", "Let $f\\colon X\\to\\overline{\\mathbb{R}}_{\\geq 0}$ be a measurable function. Show that $$ \\int f\\, d\\mu=\\int\\limits_0^{\\infty}\\mu(\\left\\{x\\in X: f(x)&gt;t\\right\\})\\, dt. $$ (The right integral is to be read as an Lebesgue-integral.) Hello, my idea is to approximate $f$ by the functions $$ f_n:=2^{-n}\\sum\\limits_{k=1}^{\\infty}\\chi_{\\left\\{x\\in X: f(x)&gt; k/2^n\\right\\}}. $$ With this approximation by simple functions I got $$ \\int\\limits_X f\\, d\\mu=\\lim\\limits_{n\\to\\infty}\\int\\limits_X f_n\\, d\\mu=\\lim\\limits_{n\\to\\infty}\\sum\\limits_{k=1}^{\\infty}\\frac{k}{2^n}\\cdot\\mu\\left(\\left\\{x\\in X: f_n(x)=k/2^n\\right\\}\\right)\\\\=\\lim\\limits_{n\\to\\infty}\\sum\\limits_{k=1}^{\\infty}\\frac{k}{2^n}\\cdot\\mu\\left(\\left\\{x\\in X:f(x)&gt;k/2^n\\right\\}\\right) $$ This is the point where I do not come along anymore... is that right to this point and if yes: How can I continue in order to get the desired right side? With regards", "Background Video is shown in Rendered mode but not when szene is rendered i have a 3D Object and want to add a background image( if possible even a movie) to this 3D Object. I use Cycles to render and tried a plane with the image as texture. When i go into render mode, it looks like this(picture with background) and when rendered, it has no background. The key also looks into a different direction. Should i even use Cycles for this or use motion tracking? i tried to use that but had several problems. Rendered mode When scene is rendered", "What is the name of a squircle with three, five, six or more corners? I know that the second shape is a squircle, but what are the other shapes called? Is there an actual name for them? The shapes do not simply have rounded corners, but the sides have a \"circularity\". Here is a triangle with rounded corners next to the shape that I do not know the name of: \"Trircle\", \"Triarcle\", and \"Pentircle\" do not seem to be used for them, at least Google's image search does not provide any results.", "Best way to select a subset of items in a long list One of our clients wants us to build a web application to share information about the magazines he publishes. Each edition of a magazine contains a variable amount of advertisers. These advertisers come from a central pool of advertisers. This pool contains (at the moment) about 150 advertisers. Each edition of a magazine contains a subset (about 70-80) of these advertisers. Our client wants us to come up with a way for him to add 70-80 advertisers from this list of 150 to an edition of a magazine. It needs to be as fast as possible, as easy as possible and as intuitive as possible. What would be an ideal solution here? I was thinking about something in the lines of the image below. List of available advertisers. List of selected advertisers. Advertisers have a delete button. Textbox with auto-suggest for advertisers in the list on the left. &lt;Enter> removes the advertiser from the left list and adds it to the right one. Textbox gets cleared and remains focus. My colleagues suggested drag-and-drop or just one list with a checkbox for each advertiser, but those approaches force the user to do a lot of searching and clicking. With my approach the user can just keep on typing. Any other suggestions for this situation?", "Creating additional Virtual Host Ubuntu Server", "How long should it take to refresh a Developer Sandbox? I refreshed a Developer Sandbox, and almost 24 hours it is still \"pending\". Is this normal? Are there any actions I can take to speed up the process? When I created the Sandbox it took barely more than 10 minutes to create. Thanks, Adrian", "Although we didn't do any changes, this new error appeared in the GSC Structured Data section: I don't really get what it means. There are many fields for Schema.org, is homeLocation suddenly a required field? Does that make any sense?", "Finding critical points (extrema) directly without using eigenvalues If we have a function $f: \\mathbb R^3\\rightarrow \\mathbb R$ of the form: $$f(x)=(a_1x_1^2+a_2x_2^2+a_3x_3^2)e^{-x_1^2-x_2^2-x_3^2}$$ where $a_1&gt;a_2&gt;a_3&gt;0$. We can find the critical points by: $$\\frac{\\partial f}{\\partial x_1} =2x_1e^{-x_1^2-x_2^2-x_3^2}(a_1-a_1x_1^2-a_2x_2^2-a_3x_3^2)=0$$ And solving symmetrically for $x_2$ and $x_3$. We get critical points: $(0,0,0) , (\\pm 1,0,0) , (0,\\pm 1, 0) , (0,0,\\pm 1)$ We could determine the nature of them by looking at the eigenvalues of the Hessian, but is there a way to just analyse it directly? Obviously $(0,0,0)$ is a strict global minimum, but I can't quite see that the other points are. Any pointers/hints would be appreciated.", "I am currently reading Murphy's ML: A Probabilistic Perspective. In CH 3 he explains that a batch update of the posterior is equivalent to a sequential update of the posterior, and I am trying to understand this in the context of his example. Suppose $D_a$ and $D_b$ are two data sets and $\\theta$ is the parameter to our model. We are trying to update the posterior $P(\\theta \\mid D_a, D_b)$. In a sequential update, he states that, $$ (1) \\ \\ \\ \\ \\ \\ \\ \\ P(\\theta \\mid D_{a}, D_{b}) \\propto P(D_b \\mid \\theta) P(\\theta \\mid D_a) $$ However, I am slightly confused as to how he got this mathematically. Conceptually, I understand that he is saying the posterior $P(\\theta \\mid D_a)$ is now a prior used to update the new posterior, which includes the new data $D_b$, and is multiplying this prior with the likelihood $P(D_b \\mid \\theta)$. Expanding the last statement out, I have, $$ P(D_b \\mid \\theta) P(\\theta \\mid D_a) = P(D_b \\mid \\theta) P(D_a \\mid \\theta) P(\\theta) $$ but are we allowed to say $P(D_a \\mid \\theta) P(D_b \\mid \\theta) = P(D_a, D_b \\mid \\theta)$ in order to make the connection in (1)?", "Update: Now that it's 2016 I'd use PowerShell for this unless there's a really compelling backwards-compatible reason for it, particularly because of the regional settings issue with using date. See @npocmaka's What's a Windows command line statement(s) I can use to get the current datetime in a format that I can put into a filename? I want to have a .bat file that zips up a directory into an archive with the current date and time as part of the name, for example, Code_2008-10-14_2257.zip. Is there any easy way I can do this, independent of the regional settings of the machine? I don't really mind about the date format, ideally it'd be yyyy-mm-dd, but anything simple is fine. So far I've got this, which on my machine gives me Tue_10_14_2008_230050_91: rem Get the datetime in a format that can go in a filename. set _my_datetime=%date%_%time% set _my_datetime=%_my_datetime: =_% set _my_datetime=%_my_datetime::=% set _my_datetime=%_my_datetime:/=_% set _my_datetime=%_my_datetime:.=_% rem Now use the timestamp by in a new ZIP file name. \"d:\\Program Files\\7-Zip\\7z.exe\" a -r Code_%_my_datetime%.zip Code I can live with this, but it seems a bit clunky. Ideally it'd be briefer and have the format mentioned earlier. I'm using Windows Server 2003 and Windows&nbsp;XP Professional. I don't want to install additional utilities to achieve this (although I realise there are some that will do nice date formatting).", "Defining the Product of Ideals Where does the &quot;naive definition&quot; of the product of two ideals $I$ and $J$, $IJ = \\{ ij \\mid i \\in I, j \\in J \\}$ fall apart? (The product of two ideals $I$ and $J$ is defined to be $IJ := \\sum_i a_ib_i$, where each $a_i$ is in $I$ and each $b_i$ is in $J$.) Note: This is a question from a problem set I'm working on. I am not expecting a full solution for the answers, but I'd like some help knowing where to look. It seems to work fine in $\\mathbb{Z}$ and $\\mathbb{C}[x]$." ]

[ "AC: Why differentiate between Ground and Neutral? Current flows through a conductor connecting points at different potentials. Leaving aside multi-phase details, common/conventional AC systems use a 3-wire setup: Wire-1: a line/live/hot/phase wire presenting a point that oscillates between 2 potentials. Wire-2: a neutral wire presenting a point of unknown/unspecified and varying potential, that nevertheless presents some fixed/specified potential difference to Wire-1 at least some of the time. Wire-3: a ground/earth wire presenting a point at 0V potential difference to its immediate physical surroundings. Wire-1 and Wire-2, in addition to some device that is to be powered, are used to construct a closed electrical circuit. Wire-3, leaving aside EMI/shielding concerns, is used to ensure that current will flow through it, rather than the device's user, if there ever occur any faults and the device's user comes in contact with Wire-1 or Wire-2. Additionally to this however, Wire-2 and Wire-3 are at some point connected. This is done to ensure that Wire-2's potential remains close to that of Wire-3 .. which seems to be important for some reason. Now the part I don't understand is why there needs to be a distinction between Wire-2 and Wire-3 at the power socket, if there is none a few meters further down the line. I have tried to look this up, but all answers I could find so far seem incomplete. The answers depend on how the question is phrased: If the question is phrased as \"Why do we need Wire-3 in addition to Wire-2\" the answer is because \"Wire-2 may be at a substantial potential difference to its surroundings/user and thus endanger him/her if he/she ever comes in contact with it or Wire-1\". If the question is phrased as \"Why do we need Wire-2 in addition to Wire-3\" the answer is because \"Wire-2 is needed to form a closed electrical circuit\" or phrased somewhat differently \"Wire-2 is needed to create a potential difference to Wire-1 and thus for current to flow\" .. with the argument further being that when taking practical considerations into account Wire-3 can't provide a reliable/stable potential difference to Wire-1 like Wire-2 can. This doesn't really answer why there's a need to differentiate between Wire-2/Wire-3 though, considering how Wire-3 remains Wire-3 and maintains 0V potential difference to its surroundings/user, regardless of whatever else happens around it .. since that is what it's supposed to do, or phrased differently, since that is the reason for Wire-3 being useful in the first place .. right? and Wire-2 is connected to Wire-3 What am I missing here? Why is it safe to touch Wire-3 but not Wire-2, or why can Wire-3 provide a level of protection that Wire-2 can't? Why differentiate between Wire-2 and Wire-3 at the power socket but then connect them further down the line?", "Using Iterator with ModelBuilder for clipping and splitting in ArcMap?", "For which values of $a$ does $a-2 \\mid a^3+4$", "I have to figure out a way to count how many sequences are there s.t: My alphabet is $1$ up to $49$. Each number that is chosen, is chosen only once. The sequence is $6$ digits long. The sequence is in increasing order. e.g that is a valid sequence: $(1, 2, 40, 42, 43, 49)$ and this is not: $(1, 2, 40, 25, 25, 12)$ I know that for the first 3 rules the answer is: $\\binom{49}{6}\\cdot 6!$ How do I deal with the fourth?", "How do I identify SMD components? (or how do I identify any component)", "KKT points and nonlinear optimality (theory) I have some questions about Karush Kuhn Tucker conditions. I am not clear about the theory. There are plenty of theorems and I am confused with it. Let us say we have the following problem: We have a general problem, not a convex problem. $$\\min f(x)\\\\g_{j}(x)\\le 0,\\forall j\\in J\\\\h_{k}(x)=0,\\forall k \\in K. $$ I will solve it.....Lagrange function, verifying primal feasibility, dual feasibility and complementary slackness and I will get some KKT points. Now what is the conclusion? If I get no KKT point, can I say that the problem has no solution or what is the conclusion? If I get only one KKT point, is it a local minimum or even a global minimum? If I get more KKT points, what is the conclusion? In which case I will verify SOSC condition? If I get more KKT points or even for one point is it necessary? And the conclusion is what? The KKT points which satisfies the SOSC condition are strick local minimum and the poins which does not satisfy it are not the solution of the problem? I am so sorry for so many questions, but any help would be very appreciated. Thank you very much in advance.", "On September 29th, I created the tag for Today, while checking the tag description, I saw that the seems to be . Why is that? Why has the Community user \"stolen\" the spot as author of the tag?", "Sum of a Hyper-geometric series. (NBHM 2011) How to find the sum of the following series $$\\frac{1}{5} - \\frac{1\\cdot 4}{5\\cdot 10} + \\frac{1\\cdot 4\\cdot 7}{5\\cdot 10\\cdot 15} - \\dots\\,.?$$ I have no idea. I have written the general term and tested its convergence by Gauss' test for convergence, but they are neither the question nor the answer.", "How many Shutter Clicks on a New Camera considered normal? I purchased a quotes new Nikon D750 and checked the shutter count and it has 264 Shutter Clik count on it. Is that suspect of a returned purchase or used camera?", "Show that $\\lim_{x \\to +\\infty}\\left(f(x)+f'(x)\\right)=0 \\Rightarrow \\lim_{x \\to +\\infty} f(x)=0$ How to show that $\\lim_{x \\to +\\infty}(f(x)+f'(x))=0 $ implies $\\lim_{x \\to +\\infty} f(x)=0$?", "etoolbox and tabularx -- problem with `appto` I'm trying to print worksheets. I have already implemented an automatic numbering for subtasks. I use tabularx for my subtasks (see the MWE below). Yesterday, I tried to define a new macro called \\task that has one optional argument which is the amount of points you can obtain for this particular question. I would like these optional arguments to be gathered with etoolbox's \\appto command so that I can print them with my \\credits command. So far, this seems to be ind of struggling as tabularx is working on the tables several times. Every time tabularx calculates the width of X columns the points are appended to \\credits which leads to an incorrect list of points. Is there any way I can solve this problem? I'm currently stucked with this issue. Plus, I don't know why my \\task command does work. Why is the counter subtask not affected by tabularx's several trials? \\documentclass{scrartcl} \\usepackage[utf8]{inputenc} \\usepackage[T1]{fontenc} \\usepackage{etoolbox} \\usepackage{booktabs} \\usepackage{ltablex} \\usepackage{xifthen} \\def\\credits{} \\newcounter{subtask} \\setcounter{subtask}{1} \\renewcommand{\\thesubtask}{\\alph{subtask})} \\newcommand{\\task}[1][]{% \\ifthenelse{\\isempty{#1}}{% \\thesubtask% \\stepcounter{subtask}% }{% \\thesubtask% \\gappto\\credits{(#1)}% \\stepcounter{subtask}% }% } \\begin{document} \\begin{tabularx}{\\linewidth}[l]{l@{\\hspace*{1ex}}X} \\task[1] &amp; TEXT1\\\\ \\task &amp; TEXT2\\\\ \\task[3] &amp; TEXT3 \\end{tabularx} \\credits \\end{document} The solution given by David Carlisle below causes a table that is too wide. How can this be undone? \\documentclass{scrartcl} \\usepackage[utf8]{inputenc} \\usepackage[T1]{fontenc} \\usepackage[a6paper, showframe=true]{geometry} \\usepackage{etoolbox} \\usepackage{booktabs} \\usepackage{ltablex} \\usepackage{xifthen} \\def\\credits{} \\newcounter{subtask} \\setcounter{subtask}{1} \\renewcommand{\\thesubtask}{\\alph{subtask})} \\makeatletter \\newcommand{\\task}[1][]{% \\ifx\\hfuzz\\@tempdima% % % tabularx trial do nothing \\else% \\ifthenelse{\\isempty{#1}}{% \\thesubtask% \\stepcounter{subtask}% }{% \\thesubtask% \\gappto\\credits{(#1 BE)\\\\}% \\stepcounter{subtask}% }% \\fi } \\makeatother \\begin{document} \\begin{tabularx}{\\linewidth}[l]{l@{\\hspace*{1ex}}X} \\task[1] &amp; Some longer text that exceedes the line width.\\\\ \\task[4] &amp; TEXT2\\\\ \\task[3] &amp; TEXT3 \\end{tabularx} \\credits \\end{document}", "Standard deviation of binned observations I have a dataset of sample observations, stored as counts within range bins. e.g.: min/max count 40/44 1 45/49 2 50/54 3 55/59 4 70/74 1 Now, finding an estimate of the average from this is pretty straight forward. Simply use the mean (or median) of each range bin as the observation and the count as a weight and find the weighted average: $$\\bar{x}^* = \\frac{1}{\\sum_{i=1}^N w_i} \\sum_{i=1}^N w_ix_i$$ For my test case, this gives me 53.82. My question now is, what's the correct method of finding the standard deviation (or variance)? Through my searching, I've found several answers, but I'm unsure which, if any, is actually appropriate for my dataset. I was able to find the following formula both and . $$s^{2*} = \\frac{ \\sum_{i=1}^N w_i (x_i - \\bar{x}^*)^2 }{ \\frac{(M-1)}{M} \\sum_{i=1}^N w_i }$$ Which gives a standard deviation of 8.35 for my test case. However, the Wikipedia article on gives both the formula: $$s^{2*} = \\frac{ \\sum_{i=1}^N w_i}{(\\sum_{i=1}^N w_i)^2 - \\sum_{i=1}^N w_i^2} \\sum_{i=1}^N w_i(x_i-\\bar{x}^*)^2$$ and $$s^{2*} = \\frac{1}{(\\sum_{i=1}^N w_i) - 1} \\sum_{i=1}^N w_i(x_i-\\bar{x}^*)^2$$ Which give standard deviations of 8.66 and 7.83, respectively, for my test case. Update Thanks to @whuber who suggested looking into Sheppard's Corrections, and your helpful comments related to them. Unfortunately, I'm having a difficult time understanding the resources I can find about it (and I can't find any good examples). To recap though, I understand that the following is a biased estimate of variance: $$s^{2*} = \\frac{1}{\\sum_{i=1}^N w_i} \\sum_{i=1}^N w_i(x_i-\\bar{x}^*)^2$$ I also understand that most standard corrections for the bias are for direct random samples of a normal distribution. Therefore, I see two potential issues for me: These are binned random samples (which, I'm pretty sure, is where Sheppard's Corrections come in.) It's unknown whether or not the data is for a normal distribution (thus I'm assuming not, which, I'm pretty sure, invalidates Sheppard's Corrections.) So, my updated question is; What's the appropriate method for handling the bias imposed by the \"simple\" weighted standard deviation/variance formula on a non-normal distribution? Most specifically with regards to binned data. Note: I'm using the following terms: $s^{2*}$ is the weighted variance $N$ is the number of observations. (i.e. the number of bins) $M$ is the number of nonzero weights. (i.e. the number of bins with counts) $w_i$ are the weights (i.e. the counts) $x_i$ are the observations. (i.e. the bin means) $\\bar{x}^*$ is the weighted mean.", "Foreign key constraints failures Given the following tables: CREATE TABLE `longdescs` ( `comment_id` int(11) NOT NULL AUTO_INCREMENT, `bug_id` mediumint(9) NOT NULL, `who` mediumint(9) NOT NULL, `bug_when` datetime NOT NULL, `work_time` decimal(7,2) NOT NULL DEFAULT '0.00', `thetext` mediumtext NOT NULL, `isprivate` tinyint(4) NOT NULL DEFAULT '0', `already_wrapped` tinyint(4) NOT NULL DEFAULT '0', `type` smallint(6) NOT NULL DEFAULT '0', `extra_data` varchar(255) DEFAULT NULL, PRIMARY KEY (`comment_id`), KEY `longdescs_bug_id_idx` (`bug_id`), KEY `longdescs_who_idx` (`who`,`bug_id`), KEY `longdescs_bug_when_idx` (`bug_when`), KEY `comment_id` (`comment_id`), CONSTRAINT `fk_longdescs_bug_id_bugs_bug_id` FOREIGN KEY (`bug_id`) REFERENCES `bugs` (`bug_id`) ON DELETE CASCADE ON UPDATE CASCADE, CONSTRAINT `fk_longdescs_who_profiles_userid` FOREIGN KEY (`who`) REFERENCES `profiles` (`userid`) ON UPDATE CASCADE ) ENGINE=InnoDB AUTO_INCREMENT=82727 DEFAULT CHARSET=utf8 CREATE TABLE `trace` ( `id` mediumint(9) NOT NULL AUTO_INCREMENT, `comment_id` mediumint(9) NOT NULL, `type` varchar(255) NOT NULL, `short_hash` char(22) DEFAULT NULL, `stack_hash` char(22) DEFAULT NULL, `trace_text` mediumtext NOT NULL, `quality` double NOT NULL, PRIMARY KEY (`id`), UNIQUE KEY `trace_comment_id_idx` (`comment_id`), KEY `trace_short_hash_idx` (`short_hash`), KEY `trace_stack_hash_idx` (`stack_hash`) ) ENGINE=InnoDB AUTO_INCREMENT=2 DEFAULT CHARSET=utf8 ALTER TABLE trace ADD CONSTRAINT `fk_trace_comment_id_longdescs_comment_id` FOREIGN KEY (`comment_id`) REFERENCES `longdescs`(`comment_id`) ON UPDATE CASCADE ON DELETE CASCADE; ERROR 1005 (HY000): Can't create table 'bugs4.#sql-4bb_6f1d' (errno: 150) MariaDB [bugs4]> show warnings; | Level | Code | Message | | Warning | 150 | Create table 'bugs4/#sql-4bb_6f1d' with foreign key constraint failed. There is no index in the referenced table where the referenced columns appear as the first columns. | | Error | 1005 | Can't create table 'bugs4.#sql-4bb_6f1d' (errno: 150) | Any idea why I get that error? FYI I looked it up and it appears that it was a bug but not anymore.", "Are delphi variables initialized with a value by default? I'm new to Delphi, and I've been running some tests to see what object variables and stack variables are initialized to by default: TInstanceVariables = class fBoolean: boolean; // always starts off as false fInteger: integer; // always starts off as zero fObject: TObject; // always starts off as nil end; This is the behaviour I'm used to from other languages, but I'm wondering if it's safe to rely on it in Delphi? For example, I'm wondering if it might depend on a compiler setting, or perhaps work differently on different machines. Is it normal to rely on default initialized values for objects, or do you explicitly set all instance variables in the constructor? As for stack (procedure-level) variables, my tests are showing that unitialized booleans are true, unitialized integers are 2129993264, and uninialized objects are just invalid pointers (i.e. not nil). I'm guessing the norm is to always set procedure-level variables before accessing them?", "Prove that the set of palindromes are not regular languages using the pumping lemma. Firstly I pick a language $xyz$ where $x = \\epsilon$, $y = (abb)^{k}$, $z = (bba)^{k}$ where $|y| \\ge$ the number of states in the automaton representing my language. Then $xyz = (abb)^k(bba)^k$ is a palindrome. Now I split $y$ into $uvw$, where $v \\ne \\epsilon$ contains a state visited more than once. If the language is regular then $xuv^iwz$ is within the language $\\forall i \\ge 0$. I choose $i = 2$, then $uv^2w = (abb)^n$ where $n &gt; k$. Then $xuv^2wz = (abb)^n(bba)^k$ where $n &gt; k$, which is not a palindrome. Firstly, is my reasoning for this particular proof correct? I'm unsure about how to properly apply the pumping lemma to this problem. And secondly the question asks me to state a proof for palindromes in general, whereas I only attempted to prove it for a single case. Is there an example I can choose which proves the conjecture for all palindromes? I assume not, seeing as I can't think of how that could be represented using regular expressions.", "Explanation for \"emails\"?", "leaflet geojson coordinate problem I just started to play with leflet/geojson a little. But my coordinates are not rendered properly and I have no clue what is going on. My coordinates are: 52.23943, 4.97599. They work correct with the setView function. var map = L.map('leaflet_map').setView([52.23943, 4.97599], 15); But using a geojasonFeature they are, hmmm, 'projected', somewhere east of Somalia. var geojsonFeature = { \"type\": \"Feature\", \"properties\": { \"name\": \"Coors Field\", \"amenity\": \"Baseball Stadium\", \"popupContent\": \"This is where the Rockies play!\" }, \"geometry\": { \"type\": \"Point\", \"coordinates\": [52.23943, 4.97599] } }; var myLayer = L.geoJson().addTo(map); myLayer.addData(geojsonFeature).bindPopup(\"I am a gjson point.\"); Anyone who knows what is happening here? EDIT Out of pure curiosity I changed the coordinates around [4.976143930893815,52.23925499011473] and the point appears at its correct location. A known bug!?", "$C(n,p)$: even or odd?", "Linux - Help, I'm running out of inodes!", "Is there a way to calculate the improper integral $\\int_0^\\infty \\big(\\frac{\\ln x}{x - 1}\\big)^2 dx$? What have I tried: $$\\int_0^\\infty \\Big(\\frac{\\ln x}{x - 1}\\Big)^2 dx = \\int_0^1 \\Big(\\frac{\\ln x}{x - 1}\\Big)^2 dx + \\int_1^\\infty \\Big(\\frac{\\ln x}{x - 1}\\Big)^2 dx = \\int_1^\\infty \\Big(\\frac{\\ln x}{x - 1}\\Big)^2dx + \\int_1^\\infty\\Big(\\frac{\\ln t}{\\big(\\frac{1}{t} - 1\\big)t}\\Big)^2dt = 2\\int_1^\\infty \\Big(\\frac{\\ln x}{x - 1}\\Big)^2dx$$ From the above statement we can conclude, that the integral does indeed converge, as $0 \\leq (\\frac{\\ln x}{x - 1})^2 \\leq \\frac{C}{(x - 1)^{\\frac{3}{2}}}$, for some constant $C$. However, this new form of the integral is not much helpful in finding its exact value. I also tried substituting $z = \\ln x$ , then $dz = \\frac{dx}{x}$. Then the integral becomes reduced to $2\\int_{0}^{\\infty} \\frac{z^2}{e^z(e^z - 1)^2}dz$, which, unfortunately, also does not seem to be any easier." ]

[ "The words in the node of tree I want to plot this graph, but I don't know how to code the words in the nodes. Here is my code: \\documentclass{article} \\usepackage{amsmath} \\usepackage{titletoc} \\usepackage{tikz} \\usetikzlibrary{trees,positioning,fit} \\begin{document}{\\allowdisplaybreaks[4]} \\tikzstyle{bag} = [text width=2em, text centered] \\tikzstyle{end} = [] \\begin{center} \\begin{tikzpicture}[sloped] \\node (a) at ( 0,0) [bag] {$\\ln r_0$}; \\node (b1) at ( 3,1.5) [bag] {$\\ln r_{10} + \\sigma_1\\sqrt{\\Delta t_1}$}; \\node (b2) at ( 3,-1.5) [bag] {$\\ln r_{10}$}; \\node (c1) at ( 6,3) [bag] {$\\ln r_{20} + 2\\sigma_2\\sqrt{\\Delta t_2}$}; \\node (c2) at ( 6,1.5) [bag] {$\\textrm{Mean} = \\ln r_{20} + \\dfrac{3}{2}\\sigma_2\\sqrt{\\Delta t_2}$\\\\$\\textrm{Mean Change} = \\mu_{11}\\Delta t_2 = \\ln\\dfrac{r_{20}}{r_{10}} + \\dfrac{3}{2}\\sigma_2\\sqrt{\\Delta t_2} - \\sigma_1\\sqrt{\\Delta t_1}$}; \\node (c3) at ( 6,0) [bag] {$\\ln r_{20} + \\sigma_2\\sqrt{\\Delta t_2}$}; \\node (c4) at ( 6,-1.5) [bag] {$\\textrm{Mean} = \\ln r_{20} + \\dfrac{3}{2}\\sigma_2\\sqrt{\\Delta t_2}$\\\\$\\textrm{Mean Change} = \\mu_{11}\\Delta t_2 = \\ln\\dfrac{r_{20}}{r_{10}} + \\dfrac{3}{2}\\sigma_2\\sqrt{\\Delta t_2} - \\sigma_1\\sqrt{\\Delta t_1}$}; \\node (c5) at ( 6,-3) [bag] {$\\ln r_{20}$}; \\draw [-&gt;] (a) to node [below] {} (b1); \\draw [-&gt;] (a) to node [above] {} (b2); \\draw [-&gt;] (b1) to node [below] {} (c1); \\draw [-&gt;] (b1) to node [below] {} (c2); \\draw [-&gt;] (b1) to node [below] {} (c3); \\draw [-&gt;] (b2) to node [below] {} (c3); \\draw [-&gt;] (b2) to node [below] {} (c4); \\draw [-&gt;] (b2) to node [below] {} (c5); \\end{tikzpicture} \\end{center} \\end{document} Update code use \\draw [-&gt;] (a) to node [below] {} (b1.south east); \\draw [-&gt;] (a) to node [above] {} (b2.north east); \\draw [-&gt;] (b1.south east) to node [below] {} (c1.west); \\draw [-&gt;] (b1.south east) to node [below] {} (c2.west); \\draw [-&gt;] (b1.south east) to node [below] {} (c3.west); \\draw [-&gt;] (b2.north east) to node [below] {} (c3.west); \\draw [-&gt;] (b2.north east) to node [below] {} (c4.west); \\draw [-&gt;] (b2.north east) to node [below] {} (c5.west);", "I have this struct: struct Map { public int Size; public Map ( int size ) { this.Size = size; } public override string ToString ( ) { return String.Format ( \"Size: {0}\", this.Size ); } } When using array, it works: Map [ ] arr = new Map [ 4 ] { new Map(10), new Map(20), new Map(30), new Map(40)}; arr [ 2 ].Size = 0; But when using List, it doesn't compile: List&lt;Map&gt; list = new List&lt;Map&gt; ( ) { new Map(10), new Map(20), new Map(30), new Map(40)}; list [ 2 ].Size = 0; Why?", "How to change the theme of Snap Apps? I am enjoying the new \"snap\" applications, but apps installed using this method doesn't seem to be using the system gtk theme I have set. Some use Adwaita or worse, Raleigh. How can I have them use the standard Ambience theme I'm using across the whole system?", "Let $G$ be a connected planar graph with a planar embedding where every face boundary is a cycle of even length. Prove that $G$ is bipartite. Any hints/tips will be greatly appreciated.", "How do I install different (upgrade or downgrade) PHP version in still supported Ubuntu release?", "Can you trade from Pokemon Red on GBA to Pokemon gold on virtual console? I have a Game Boy Advance SP and Pokemon Red GEN 1, and I'm curious if it is possible for me to trade a Pokemon from Red to the Virtual Console release of Pokemon Gold on the 3DS", "What is momentum really?", "If $a_{1},a_{2},a_{3},a_{4}\\in \\mathbb{R}$ and $a_{1}+a_{2}+a_{3}+a_{4}=0$ and $a^2_{1}+a^2_{2}+a^2_{3}+a^2_{4}=1.$ Then Range of $$E =(a_{1}-a_{2})^2+(a_{2}-a_{3})^2+(a_{3}-a_{4})^2+(a_{4}-a_{1})^2$$ is Try: From $$(a_{1}-a_{2})^2+(a_{2}-a_{3})^2+(a_{3}-a_{4})^2+(a_{4}-a_{1})^2$$ $$=2(a^2_{1}+a^2_{2}+a^2_{3}+a^2_{4})+2(a_{1}a_{2}+a_{2}a_{3}+a_{3}a_{4}+a_{4}a_{1})$$ $$=2-2(a_{1}+a_{3})(a_{2}+a_{4})=2+2(a_{1}+a_{3})^2\\geq 2$$ and equality hold when $\\displaystyle a_{1}=-a_{3}$ and $a_{2}=-a_{4}$ Could some help me how to find its upper bound, Thanks", "Number of factors of a big number How to find the number of factors of $884466000$ without using a calculator?", "All I want to do is to check whether an element exists in the vector or not, so I can deal with each case. if ( item_present ) do_this(); else do_that();", "Travel to Cuba as dual citizen (USA+other)?", "Adding a script to the page dynamically with jQuery never uses the cached file", "New database server hardware and software inserts slower than old setup", "Alternative IDE for VB6 and VBA", "Importing single symbol from MnSymbol", "Are there any keyboard shortcuts for Windows 10 developer preview's virtual desktops (\"Task View\")?", "A group is generated by two elements of order $2$ is infinite and non-abelian", "Can I use an \"if\" clause without \"then\"?", "How do I edit my profile? This is probably a noob question, but I forgot how to edit my profile. Can anyone help me? There is no visible button for me.", "How come gas molecules don't settle down? If the earth's gravity exerts a net downward gravitational force on all air molecules, how come the molecules don't eventually lose their momentum and all settle down? How is the atmosphere is still miles thick after billions of years?" ]

[ "Today, comparing processors is obviously not just looking at the frequency and the number of cores. When choosing a new PC, how do you compare processors? Is there some resource, like a site or something that does (not necessarily super-precise) processor comparisons? Thanks.", "80's Animated movie: An old man joins mission to save a boy stranded on a hostile world", "Short story about interstellar travel gone wrong Trying to find a story I read a couple of years ago in an anthology, not sure when the story dates from but likely to be recent - the last decade or so. The story has passengers travelling between stars via a series of jumps. The calibration of the drive is affected by a special metal, any of which has to be stored in a shielded compartment (I think the jumps were measured in 'degrees'). One of the passengers unwittingly takes some of this metal on board, which throws off the calculations for the jumps, and they jump into an alternative universe where there are no signs of any humans ever existing. They start to try to reverse their steps to get back to the known universe, but the reverse calculation seems impossible. That's as much as I read of the story before I lost the book. After many dreams (feverish nightmares!) re-living this story, I need to know how it ends. I know it's not much to go on. The story name, author, or the anthology it appears in would be fantastic.", "What's the recommend way of changing the font size in a particular table? Is there a better way than enclosing all values with, for example, the \\tiny function.", "I have 41 GB of space on my E:/ drive. Is it sufficient to install Ubuntu? My Windows XP is installed in C:/ drive. Is it OK for dual boot? Should I install Ubuntu (I am installing using Live CD). I don't want to lose my Windows option.", "Get the image URL I want to render an image as a background image via an inline style in twig. I created a field called bg_image and attached it to the standard plain page. After fiddling around for hours I was able to get the Image URL in node.html.twig {{ file_url(node.field_bg_image.0.entity.uri.value) }} but I could not get it to work inside field--field-bg_image.html.twig Can I get the node from there anyhow, so I can then get the image? How can I get the image URL to use as inline style? I thought maybe I can pass a variable from field--field-bg_image.html.twig to image.html.twig and then just render {{ uri }} instead of &lt;img{{ attributes.addClass(classes) }} /&gt; but I could not get it to pass the variable there unless I use includes {% include 'image.html.twig' with {'image': image, 'isFromField': isFromField} %} (isFromField is true, when it comes from the field--field-bg_image.html.twig) But that didn't work either. The Image was never rendered that way. Would be very glad if you can help - my php knowledge is very basic. Thanks", "Could someone advise me on how to determine all entire functions $f$ such that $|f'(z)| \\leq |f(z)|, \\forall z\\ ?$ Hints will suffice, thank you.", "How to fix a stripped pedal crank The threads on my bike's pedal crank just became fully stripped and the pedal fell off, though the pedal itself is fine. Is there any way I can fix this without fully replacing the pedal crank?", "Given n distinct objects, there are $n!$ permutations of the objects and $n!/n$ \"circular permutations\" of the objects (orientation of the circle matters, but there is no starting point, so $1234$ and $2341$ are the same, but $4321$ is different). Given $n$ objects of $k$ types (where the objects within each type are indistinguishable), $r_i$ of the $i^{th}$ type, there are \\begin{equation*} \\frac{n!}{r_1!r_2!\\cdots r_k!} \\end{equation*} permutations. How many circular permutations are there of such a set?", "Let $m$ and $n$ be two integers. Prove that if $m^2 + n^2$ is divisible by $4$, then both $m$ and $n$ are even numbers. I think I have to use the contrapositive to solve this. So I assume $\\neg P\\implies Q$ and I have to derive $\\neg Q$? I know its easier to show odd numbers rather than even... but im still unsure how to do this practice problem.", "What is the best way(s) to fake function overloading in Javascript? I know it is not possible to overload functions in Javascript as in other languages. If I needed a function with two uses foo(x) and foo(x,y,z) which is the best / preferred way: Using different names in the first place Using optional arguments like y = y || 'default' Using number of arguments Checking types of arguments Or how?", "Will there be data loss if I upgrade?", "Do continuous linear functions between Banach spaces extend?", "How to make a package manager wait if another instance of APT is running? I have seen many softwares such as Update Manager and Synaptic Package Manager, they wait if some other program is using the /var/lib/dpkg/lock and is locked. How can we do this through the Terminal? I saw apt-get's manual but didn't find anything useful.", "Can we implement the low quality flags to delete posts after a certain number of flags? Can we implement the low quality flag to be like the abuse or spam flags. So if a certain number of low quality flags are made on a post (whether it be a questions or an answer) the post is deleted? This would also relieve *close vote and delete vote queues. *which is a much discussed topic. related:", "Are collective nouns always plural, or are certain ones singular? I'd say Microsoft have a way of bending the rules and I know that McLaren have won the championship. While this sounds strange, I believe it is correct English (sorry, I'm not native). But when it's a small company, would you still use it this way? Is a company always plural, or are small companies singular? I.e., would you say Bakery Johnson makes fine bread or Bakery Johnson make fine bread? Is it My book seller, Woody's, have moved or is it has moved?", "Wireless antenna does not appear despite its driver being installed", "Why is a conservative force defined as the negative gradient of a potential? I'm learning about work in my dynamics class right now. We have defined the work on a particle due to the force field from point A to point B as the curve Integral over the force field from point A to B. From math I know that if a vector field has a potential, we only need to evaluate the potential at point B minus the potential at point A to get the result of the curve Integral. In the text that I'm reading, it's explained that if the integral over a force-field is path-independent, then the force field $F = -{\\rm grad}(V)$, where $V$ is the potential. Why is it defined as the negative gradient? Doesn't one determine the potential from $F$ mathematically. Why do we impose the sign on the potential?", "How are Clash of Clans multiplayer battles determined Are battles determined by level or trophies? Just curious.", "I'm looking for a library/method to parse an html file with more html specific features than generic xml parsing libraries." ]

[ "'sudo su -' vs 'sudo -i' vs 'sudo /bin/bash' - when does it matter which is used, or does it matter at all?", "Is is possible to skip the confirmation step while adding a repository? When I add a repository by running sudo add-apt-repository ppa:ubuntu-x-swat/x-updates It outputs this dialog: Updated versions of X.org drivers, libraries, etc. for Ubuntu. This PPA is for stable upstream releases of X.org components. If you're looking for something even more bleeding-edge, please see the xorg-edgers PPA. While Ubuntu does not \"officially/formally\" support these packages, if you discover problems when installing these debs please feel free to report bugs to launchpad. However, please make sure to clearly state that you are running packages from this PPA so we know the fixes need to come here. If you are upgrading from one release to another with this PPA activated, please install the ppa-purge package and use it to downgrade everything in here beforehand. sudo ppa-purge ppa:ubuntu-x-swat/x-updates will do it. [Directions for packaging drivers can be seen at https://wiki.ubuntu.com/X/DriverBuilding] More info: https://launchpad.net/~ubuntu-x-swat/+archive/x-updates Press [ENTER] to continue or ctrl-c to cancel adding it I want to skip the confirmation step Press [ENTER] to continue or ctrl-c to cancel adding it How can I automatically confirm the addition of a PPA?", "I stumbled upon an example, which needed to be compiled with the additional option --shell-escape. Using this option it worked just fine, but I'm curious: Why or when is this option needed and what does it actually do?", "Get in vs. get on Possible Duplicate: I'm an EFL (English as a foreign language) teacher and I haven't been able to come up with a good principle for which preposition to use after get when referring to transportation. Some examples: Get in: a car/taxi/van/truck, etc. Get on: a bus/plane/bike/truck, etc. How can one choose whether to use in or on? Note that in some cases, such as the example with truck, either preposition is possible but the choice affects the meaning. I've been telling my students that there is no rule, so they just have to memorize which preposition to use, but I'm really hoping I'm wrong. This question would be better suited for the upcoming Stack Exchange, but it hasn't entered beta yet. More .", "Why Oracle discontinued Oracle Java (JDK) Installer PPA?", "What is the name of this theorem, and are there any caveats? For random variable $X$ that follows some distribution, $f(x)$ is the probability density function of that distribution if and only if $$\\mathbb{E}[\\phi(X)] = \\int_{-\\infty}^\\infty \\phi(x) f(x)dx$$ for all functions $\\phi$. Context: My professor used this in lecture to demonstrate a way to find the distribution of $cX$ given random variable $X$ that follows a specific distribution. What is the name of this theorem? Have I missed any qualifications/caveats? I am in particular curious about whether \"for all functions\" is correct. My professor mentioned \"positive, bounded, deterministic functions,\" but I am not sure what he meant by that. Where can I find a proof of this theorem?", "How to read and write into file using JavaScript? Can anybody give some sample code to read and write a file using JavaScript?", "Can I connect a PC to a PoE switch?", "How to call shell script from php that requires SUDO?", "How to make a file executable? How can I make my file so that I can double click on it, and it runs. It is a .sh script, but I also have files that say: executable (application/x-executable) in the description of what they are. I can't run any of these from terminal, or by double clicking. If possible, I would like a way using either the GUI or a Terminal, but not a combination of the two. Here is a screenshot of what I see when I right click then go on properties. The file first: And the shell script here: NB: I accept that this is a duplicate (I was looking for it, and couldn't find it, so asked + answered it, hoping that I would find it) however, I don't think the question about .desktop files is a duplicate.", "I am a girl in my early twenties traveling to USA from India and in my visa application I have provided the contact address for a relative in San Francisco, and their invitation letter. I would like to visit LA first. Will I face problems during immigration if I land in LA (with an immediate on wards ticket to SF)? I dont plan to get on the flight from LA to SFO. Initially I was planning to fly to SFO from India and then fly to LA immediately after completing immigration at SFO airport.", "This is my last homework problem and I've been looking at it for a while. I cannot nail down what is wrong with this proof even though its obvious it is wrong based on its conclusion. Here it is: Find the flaw in the following bogus proof by strong induction that for all $n \\in \\Bbb N$, $7n = 0$. Let $P(n)$ denote the statement that $7n = 0$. Base case: Show $P(0)$ holds. Since $7 \\cdot 0 = 0$, $P(0)$ holds. Inductive step: Assume $7·j = 0$ for all natural numbers $j$ where $0 \\le j \\le k$ (induction hypothesis). Show $P(k + 1)$: $7(k + 1) = 0$. Write $k + 1 = i + j$, where $i$ and $j$ are natural numbers less than $k + 1$. Then, using the induction hypothesis, we get $7(k + 1) = 7(i + j) = 7i + 7j = 0 + 0 = 0$. So $P(k + 1)$ holds. Therefore by strong induction, $P(n)$ holds for all $n \\in \\Bbb N$. So the base case is true and I would be surprised if that's where the issue is. The inductive step is likely where the flaw is. I don't see anything wrong with the strong induction declaration and hypothesis though and the math adds up! I feel like its so obvious that I'm just jumping over it in my head.", "Variables in batch file not being set when inside IF? I have two examples of very simple batch files: Assigning a value to a variable: @echo off set FOO=1 echo FOO: %FOO% pause echo on Which, as expected, results in: FOO: 1 Press any key to continue . . . However, if I place the same two lines inside an IF NOT DEFINED block: @echo off IF NOT DEFINED BAR ( set FOO=1 echo FOO: %FOO% ) pause echo on This unexpectedly results in: FOO: Press any key to continue . . . This shouldn't have anything to do with the IF, clearly the block is being executed. If I define BAR above the if, only the text from the PAUSE command is displayed, as expected. What gives? Follow up question: Is there any way to enable delayed expansion without setlocal? If I were to call this simple example batch file from inside another, the example sets FOO, but only LOCALLY. For example: testcaller.bat @call test.bat @echo FOO: %FOO% @pause test.bat @setlocal EnableDelayedExpansion @IF NOT DEFINED BAR ( @set FOO=1 @echo FOO: !FOO! ) This displays: FOO: 1 FOO: Press any key to continue . . . In this case, it appears that I have to enable delayed expansion in the CALLER, which may be a hassle.", "Like most Python developers, I typically keep a console window open with the Python interpreter running to test commands, dir() stuff, help() stuff, etc. Like any console, after a while the visible backlog of past commands and prints gets to be cluttered, and sometimes confusing when re-running the same command several times. I'm wondering if, and how, to clear the Python interpreter console. I've heard about doing a system call and either calling cls on Windows or clear on Linux, but I was hoping there was something I could command the interpreter itself to do. Note: I'm running on Windows, so Ctrl+L doesn't work.", "How can I model the mechanics of an army battlefield scene? TL;DR; I want to model a strategic battlefield fight for my players to command and participate. I'm seeking advice on how to model it mechanically so that it is exciting for the players. Background The final scene of Act II of my campaign is envisioned to be a big battle between the army of the Big Bad and the allied forces gathered by my players. The full set of Act II runs with the players gaining the allegiance of the different factions to support them on the fight. Now, in terms of that final scene, I'm struggling to decide how to DM the fight. In games and movies the action is made epic by having cinematic scenes of the fight happening with cuts to our heroes doing their amazing things, be it just plowing through dozens of enemies in quick succession or fighting the big ugly overpowered monster that is otherwise cause havoc among the army. I want that feeling The set up will involve an army of several thousand enemies agains the different forces gathered by my players. Depending on what they've done during the second act, they'll have more or less support with a minimum number of regiments belonging to several faction (i.e. the silver guard of Wizardwight). Intended way of DMing the scenario. What I've come up with is to have the players be military leaders. Draw the map of the battlefield and have them manage the battlefield strategically and tactically, distributing the units and, somehow, enabling a dice based mechanism to evaluate how well each unit is doing. This will transform the tabletop into something similar to Warhammer Fantasy. They can choose to join a particular place of the battlefield to help either together or separately. I have absolutely no idea on how to model this mechanically (as far as I know D&amp;D 5e does not cover this kind of fights). Question: What are good ways to mechanically model this kind of strategic army combat? Should I switch to a different system just for this scene or can I model this with D&amp;D 5e? Notes on level: At this point I expect my players to range between level 9-12 and for the party to be between 3 and 4 players (this is not a limitation of the campaign, more like the players I'm running the campaign with).", "Is there an option to output a manual page in a different language? I don't want to change the computer language completely, but only specific manual pages. For example $ man -English man Man is a manual program … $ man -Russian man Инструцтия для Unix, BSD и Linux. …", "How can I prove that if $n$ is even then $n^2$ is even and if $n$ is odd then $n^2$ is odd?", "Highlighted source code inline with Latex/Minted?", "When is the Killing form null?", "Any way to control light halos in the compositor based on emission level? I am wanting to animate a row of LED lights. I have separated the LED lights from the rest of my object with the pass index/ID mask functions; currently all of my LED lights are on pass index #1. What I want is to have a minor halo effect around the lights, but only when they are active. Currently, when I add a halo effect to my pass index #1, all of the LED lights have a halo effect regardless if the LEDs are emitting light. All LEDs are diffuse and emission shaders, so I can animate by controlling the mix amount between diffuse and emission. Is there any simple way to have the halo effect created through recognizing light emission values, or will I have to just animate each LED as its own layer of compositing?" ]

[ "Printer \"Filter failed\" Upgraded to 18.04 from 16.04. I have a workplace printer connected through appsocket which stopped working. Printer status is Idle-Filter failed. Printing queue instantly goes to \"stopped\". Right clicking on the printer shows \"option finishings has value 3 and cannot be changed\". I can't find any info on this error except one pdf to ignore the error. The printer model Ricoh MP 2555 worked previously with the Ricoh MP C2800 driver. Now it works with neither 2800 or 2555. The IP address of the printer pings fine. When I try and detect the printer on the network using IP address and I ask it to use the Ricoh MP 2555 driver, it asks for an additional driver which opens Ubuntu software (which never helps) and fails. I tried changing drivers from \"\" by providing the ppd file. It still doesn't help. var/log/cups/error.log doesn't tell much, or I don't get it. Hope someone knows about this error or some kind of a generic solution.", "How do you rename root? Not that it's a very good idea to change it, but for fun. According to post, there are still some problems even after changing entries in /etc/passwd, /etc/shadow, and /etc/sudoers. Any suggestions?", "Short Question: Why can we manipulate a read-only file in Vim using : + w + q + ! even without being an administrator? Long Question: I have a text file (myFile.txt) which is read-only for everyone: navid@navid-ThinkPad-T530:~/ubuntuTest$ ls -l myFile.txt -r--r--r-- 1 navid navid 26 Aug 22 21:21 myFile.txt I can open it with Vim without having admin privileges: navid@navid-ThinkPad-T530:~/ubuntuTest$ vi myFile.txt I modify it and press: Esc + : + w + q + Enter and I see this error message: E45: 'readonly' option is set (add ! to override) So far, everything makes sense. But when I press: Esc + : + w + q + ! + Enter, Vim saves the changes. I'm using Ubuntu 16.04 and VIM 7.4.", "Proof for alternative definition of the derivative I read somewhere recently that you can define the derivative as follows: $$f'(x) = \\lim_{h, k \\to 0^+} \\frac{f(x +h) - f(x - k)}{h + k}$$ I have been trying to prove this for about 2 hours, and can't seem to get it done. How should I proceed? Edit: Assume $f$ is differentiable for all $x \\in (x - \\delta, x + \\delta)$ for some $\\delta &gt; 0$.", "As far as I understand, whatever can be done using DeclareMathOperator can also be achieved using newcommand, but not the other way around. If this is the case, what are the circumstances where DeclareMathOperator is the better choice? When should I take solely newcommand? I found a question regarding , and I wonder what other aspects should be taken into consideration when it comes to choosing which method to use when defining math operators.", "What's the difference between declaring a variable \"id\" and \"NSObject *\"? In Objective-C, what's the difference between declaring a variable id versus declaring it NSObject *?", "Help Text not showing on I have a table inside of a pageblocksection and then inside of that I have an that I am trying to utilize the default help text for but it's not showing up. &lt;apex:pageBlockSection columns=\"1\"&gt; &lt;apex:outputPanel&gt; &lt;table&gt; width=\"100%\"&gt; &lt;tr&gt; &lt;td&gt; &lt;apex:pageBlockSectionItem helpText=\"test text\"&gt; &lt;apex:inputCheckbox value=\"{!searchBySKU}\" /&gt; &lt;apex:outputLabel value=\"Search for this SKU or text in the SKU name\" /&gt; &lt;/apex:pageBlockSectionItem&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; &lt;/apex:outputPanel&gt; &lt;/apex:pageBlockSection&gt; Any ideas why this doesn't work as I expect? EDIT: So, I just did some more testing and it creates the text if it's a direct child of the pageBlockSection. Is there any way to get around this restriction without going the fully custom route to do so?", "Attaching towel rail to drywall", "I was wondering what the proper LaTeX code would be to display something like this: You don't have to include the mathematical symbols, what is important is the structure.", "Shifting -5 V to +5 V signal to 0 to +5 V for ADC I want to convert the output voltage of an ECG (-5 to +5) to 0 - +5 volt for ADC. Should i use Op amp ? What is my problem in this picture? I simulated it in Proteus ... but when input voltage is higher than 4 V or lower than -4 V Vout gives an unexpected value. Below is another simulink that have same problem ... My idea to make this level of voltage is (Vin +10)/2 that give the range 0-5 V.", "ImportError: No module named dbus I was trying to update my Python and messed up my whole system. I am currently now able to start my Software Centre. I tried Googling multiple fixes but nothing helped. My Software Centre can't start. When I try starting it up, this error shows: astephen@localhost:/usr/bin$ ./software-centerGtk-Message: Failed to load module \"gtk-vector-screenshot\" Traceback (most recent call last): File \"./software-center\", line 36, in &lt;module&gt; from softwarecenter.utils import ( File \"/usr/share/software-center/softwarecenter/utils.py\", line 19, in &lt;module&gt; import dbus ImportError: No module named dbus I tried reinstalling dbus using: apt-get install --reinstall dbus But it did not help. astephen@localhost:/usr/bin$ sudo apt-get install --reinstall dbusReading package lists... Done Building dependency tree Reading state information... Done 0 upgraded, 0 newly installed, 1 reinstalled, 0 to remove and 0 not upgraded. Need to get 0 B/231 kB of archives. After this operation, 0 B of additional disk space will be used. (Reading database ... 676272 files and directories currently installed.) Preparing to unpack .../dbus_1.6.18-0ubuntu4.3_amd64.deb ... Unpacking dbus (1.6.18-0ubuntu4.3) over (1.6.18-0ubuntu4.3) ... Processing triggers for ureadahead (0.100.0-16) ... Processing triggers for man-db (2.6.7.1-1ubuntu1) ... Setting up dbus (1.6.18-0ubuntu4.3) ...", "Show badges in user profile in iOS app When viewing a user's profile from the iOS app, it would be nice to be able to see what badges they have, instead of just the counts.", "WPF textblock binding with List does anyone know if there is a simple way to bind a textblock to a List. What I've done so far is create a listview and bind it to the List and then I have a template within the listview that uses a single textblock. what I'd really like to do is just bind the List to a textblock and have it display all the lines. In Winforms there was a \"Lines\" property that I could just throw the List into, but I'm not seeing it on the WPF textblock, or TextBox. Any ideas? did I miss something simple? Here's the code &lt;UserControl x:Class=\"QSTClient.Infrastructure.Library.Views.WorkItemLogView\" xmlns=\"http://schemas.microsoft.com/winfx/2006/xaml/presentation\" xmlns:x=\"http://schemas.microsoft.com/winfx/2006/xaml\" Width=\"500\" Height=\"400\"&gt; &lt;StackPanel&gt; &lt;ListView ItemsSource=\"{Binding Path=Logs}\" &gt; &lt;ListView.View&gt; &lt;GridView&gt; &lt;GridViewColumn Header=\"Log Message\"&gt; &lt;GridViewColumn.CellTemplate&gt; &lt;DataTemplate&gt; &lt;TextBlock Text=\"{Binding}\"/&gt; &lt;/DataTemplate&gt; &lt;/GridViewColumn.CellTemplate&gt; &lt;/GridViewColumn&gt; &lt;/GridView&gt; &lt;/ListView.View&gt; &lt;/ListView&gt; &lt;/StackPanel&gt; and the WorkItem Class public class WorkItem { public string Name { get; set; } public string Description { get; set; } public string CurrentLog { get; private set; } public string CurrentStatus { get; private set; } public WorkItemStatus Status { get; set; } public ThreadSafeObservableCollection&lt;string&gt; Logs{get;private set;} I'm using Prism to create the control and put it into a WindowRegion WorkItemLogView newView = container.Resolve&lt;WorkItemLogView&gt;(); newView.DataContext = workItem; regionManager.Regions[\"ShellWindowRegion\"].Add(newView); thanks", "I've installed Ubuntu 13.04 two times on my PC. Each on a different partition. I would like to delete the one which I'm not using. How would I do that?", "How can I get Gnome3 to remember my session? I am running Gnome3, but I had the same problem with Unity, on Ubuntu 12.04. I have a fairly elaborate setup I enjoy using day-to-day. A LibreOffice spreadsheet with everyone's extension numbers; a window with reference data I use regularly; two mulit-tabbed Konsole/Terminal windows with several remote systems sessions, firefox with a set of open tabs, and so on. But whenever I log out, when I return, I must set up everything from scratch. I remember the good 'ol days, when I rebooted, I'd re-log in, and all my windows came back up in the same places as they were when I logged out, and my Konsole/Term would come up with the same remote logins as before.... I'd have to re -setup some of my programs, but that's better than having to move every win into place, and resize them, etc. How do I get this functionality back?", "What are the answers for these basic quetions?", "Get complete stats of process started/terminated during login of user account When I login, I notice many process quickly start and terminate in task manager. But it happens very fast and I cannot save details about them (like process name, command line, CPU usage,..) How can I collect stats about them so I can view them later", "Date Formatting C#", "The feeling of always wanting newer possessions? I am looking for a word that describes the emotion or feeling of an intrinsic want of a new and better possession. Covetous or envious seem a bit too focused on the other other person's possession of the desired object whereas I am looking for something that is defined by the internal thoughts we have when seeing an advertisement for the latest iPhone or life-changing new service. but I am wondering if there is a word with less emphasis on the second entity? Otherwise, would I covet new things from Amazon or Apple? Can I be envious of corporations? For example, I just bought a new car and now, looking at my slightly out of date television, I feel the need to upgrade my T.V. with a newer, shiny one from Amazon. Would I be coveting that T.V. which Amazon sells? I saw the ad for the latest iPhone, the iPhone 3000, and feel that my current phone is inadequate. I am a(n) ______ person, since I always desire something better than what I currently possess. If I was a caveman with a sharpened stick, I'd want your sharper, pointier stick. I feel like there is probably some niche German word for exactly this, but I'm unsure it exists in English. Thanks!", "Improving our spatial data by calculating \"Close to Coastline\", \"Close to Park\", \"Close to Stadium\" etc A quick background for context is maybe helpful for this. Essentially we have \"vacation rentals\" and I would like to add additional data to them automatically. We create booking websites for customers who have very niche sites, for example, \"Pet Friendly\" rentals. \"Olympic Cottages\" \"Surfing Adventure Lettings\". Quite often each of our customers always ask the same questions, \"It would be awesome if we could plot the distance and sort properties based on their relative distance from XYZ\". Usually XYZ is something like a list of dog friendly beaches, or cycle tracks, or wine vinyards. So esesntially points of interests which are easily definable. In those cases, we've always just asked the customer to provide a list of the lat/lngs of every possible \"point of interest\" that they would like us to calculate distance from\". More recently we've been asked to include \"Close to Coastline\". What I want is to come up with a standard way of automating this. My ideas so far are to create a shapefile. For example, let's say we wanted to do \"Close to Coastline\", we could use something like At this point, I'm somewhat stuck in knowing how would be most efficient to calculate the distance from the edge of the coastline. I'm thinking about being able to just create/add a shapefile per \"concept\" that the customer wants us to use for their product. But then do not know the process/tools available to me to know distance from each edge, or vector point." ]

[ "Given $f(x) = x + |x|$ for what values of $x$ is $f$ differentiable Problem : Given $f(x) = x + |x|$ for what values of $x$ is $f$ differentiable? For the sake of generality, let's assume that it is unknown to us that $|x|$ is not differentiable at $x = 0$ Attempted Solution : Using the definition of differentiability, a function is differentiable over an interval $I$ $\\text{iff}$ $$f'(x) = \\lim_{h \\to 0} \\frac{f(x+h)-f(x)}{h}, \\ \\ \\forall x\\in I$$ Now implicitly this definition of differentiability requires $$\\lim_{h\\to 0^+} \\frac{f(x+h)-f(x)}{h} = \\lim_{h\\to 0^-} \\frac{f(x+h)-f(x)}{h}$$ Therefore $f$ will be differentiable only when $$\\lim_{h\\to 0^+} \\frac{(x + h + |x+h|)-(x + |x|)}{h} = \\lim_{h\\to 0^-} \\frac{(x - h + |x-h|)-(x + |x|)}{h}$$ But it is unclear what to do next as $x$ is just arbitrary $$ \\begin{equation} \\begin{aligned} |x+h| &amp;= \\begin{cases}x+h &amp; \\text{if} &amp; x \\geq -h\\\\ -x-h &amp; \\text{if} &amp; x &lt; -h \\end{cases} \\\\ &amp;= \\begin{cases}x+h &amp; \\text{if} &amp; x \\geq 0\\\\ -x-h &amp; \\text{if} &amp; x &lt; 0 \\end{cases} \\end{aligned} \\end{equation}$$ A Wrong Solution : We could take the derivative of $f$, (and evaluate the domain of the derivative $f'(x)$ to values for which it is defined), using the rules of differentiation, but we would get a wrong answer. $$f'(x) = \\frac{|x| + x}{|x|}$$ $$\\implies f'(x) = \\begin{cases} 2 &amp; \\text{if} &amp; x \\geq 0 \\\\ 0 &amp; \\text{if} &amp; x &lt; 0 \\end{cases}$$ This implies the derivative $f'(0)$ exists, when it does not as per the definition of differentiability. Why is that so? Questions: How can a solution be found using the definition of differentiablity? Why does taking the derivative of $f$, $f'(x)$ and evaluating it's domain, not give the correct values of $x$ for which $f$ is differentiable?", "Financial requirements to sponsor relatives visiting the Schengen area [Germany]?", "MacOS 10.14 Mojave public beta public Wi-Fi problem I can not connect to a single public Wi-Fi hotspot that does not require a password but instead shows a pop-up window pointed to captive.apple.com The pop-up opens blank with the error \"The web page couldn't be loaded\" Any idea on how to fix this?", "Inadvertent use of = instead of == It seems that if (x=y) { .... } instead of if (x==y) { ... } is a root of many evils. Why don't all compilers mark it as error instead of a configurable warning? I'm interested in finding out cases where the construct if (x=y) is useful.", "How to prevent iTerm2 from creating overlaps and broken lines after pasting multiline chunks of text? If I paste multiline chunks of text into iTerm2, I always a get mess of output. It seems limited to only some programs running interactively (such as Bash, IRB - Python / VIM work flawlessly). Using Apple's native Terminal, I can paste whatever I want wherever I want - it works. For example, this sample text (): echo Lorem ipsum dolor sit amet, consectetur adipiscing elit. Donec a diam lectus. echo Sed sit amet ipsum mauris. Maecenas congue ligula ac quam viverra nec consectetur ante hendrerit. echo Donec et mollis dolor. Praesent et diam eget libero egestas mattis sit amet vitae augue. echo Nam tincidunt congue enim, ut porta lorem lacinia consectetur. Donec ut libero sed arcu vehicula ultricies a non tortor. echo Lorem ipsum dolor sit amet, consectetur adipiscing elit. Aenean ut gravida lorem. Ut turpis felis, pulvinar a semper sed, adipiscing id dolor. echo Pellentesque auctor nisi id magna consequat sagittis. Curabitur dapibus enim sit amet elit pharetra tincidunt feugiat nisl imperdiet. echo Ut convallis libero in urna ultrices accumsan. Donec sed odio eros. Donec viverra mi quis quam pulvinar at malesuada arcu rhoncus. [snip] pasted into IRB produces this in iTerm2: while it produces this in native Terminal: I am running the latest versions of OSX and iTerm2. What's going wrong here?", "I have a BA degree in Biochemistry. I worked at a research lab for 5 yrs before I quit my job to be a stay at home. Now I want to change my career and get into the field of QA. I don't have much knowledge as to what the best way is to get into this field. I cant afford to take online courses, so I want to self teach it to me. Any suggestions and help would be greatly appreciated.", "Determine if Type is a pointer in a template function", "Recently I have updated my postgresql version. I have also upgraded pgAdmin from 3 to 4. But I was unable to load shapefile. I didn't find any plugin called shapefile loader. How can I get the shapefile loader plugin in pgAdmin 4?", "How do I get permissions to edit system configuration files?", "What is the smallest viable reproducing population, such as in a human population. By viable I mean a population which keeps genetic defects low (enough). A very strongly related question: what is the expected number of generations a given population can survive?", "Brownian motion - Hölder continuity", "I have just dropped a half full latté on my company laptop and am not sure what to do. Is there a way I can make sure that my laptop is usable again? What steps must I go through to improve it's chances of survival?", "A sine integral $\\int_0^{\\infty} \\left(\\frac{\\sin x }{x }\\right)^n\\,\\mathrm{d}x$ The following question comes from post $$\\int_0^{\\infty} \\left(\\frac{\\sin x }{x }\\right)^n\\,\\mathrm{d}x$$ but now I'd be curious to know how to deal with it by methods of complex analysis. Some suggestions, hints? Thanks!!! Sis.", "Many of the people have asked almost the same question. I'm trying to render a big mesh + fur/grass file with a few characters on the screen. when I hit render, after a number of processing, copying data to gpu etc... i get following error. Mem: 2960.07M, Peak:2960.07M | CUDA error: Out of memory in cuMemAlloc(&amp;device_pointer, size). I'm using Geforce GTX 690 which contains 4GB memory. Can somebody tell me how can i get GPU rendering, while 2960M is far less then 4196M of memory. I know somebody would suggest me to use CPU.. but i'm curios why not GPU? I've already compressed texture, etc Edited I don't think any other application is using any of my 1GB remaining memory. everything is closed but blender is there, also the GPU utilities are showing 2000/2000 MB are free on one card and 1900/2000MB is free on 2nd card. i'm using GTX 690. with two GPUs of 2GB each. If somebody thinks that one GPU should have memory matching to the cuda memory/or Peak memory then I'm doubtful. Because in preferences Blender does know that I have 2GPUs where I can select either first GPU or second GPU or even both. When I render some of smaller objects/scenes both of my GPU renders simultaneously with two blocks. I'm running following specs Xeon E5-1660 0 24GB - 1600mhz GTX690", "Why no file-name in Inode information? I know that symlinks have a separated inode from the original file and that they only point for the inode containing the data. My question is, where is the hardlink name stored if there's no field in the inode structure refering to \"name\". I know that this could be a a relatively easy question, but as all hardlinks have the same inode number i assume that no inode is created when creating a hard link.", "First let me explain what I mean by \"transitive\" Suppose that the price of product A and the price of product B has a correlation of .5 Suppose also that the price of product B and product C has a correlation of .5 One might thing that if correlation(A,B) = .5 and correlation(B,C) = .5 then correlation(A,C) > 0, but with an intuitive example we can see why this is not the case: Suppose that A is a fruit salad made of papaya and banana, suppose also that B is a fruit salad made of banana and strawberry and, finally, suppose that C is strawberries and cream. Clearly, when the price of banana goes up, both the price of A and B will go up; when the price of strawberry goes up the price of B and C will go up; but since A and C have no ingredients in common, their price isn't correlated. My question is which statistical concept captures this intuitive idea. Is it the concept of dimensions? What do I mean by transitive? Let me define the binary operator X corr? Y as 1 if correlation(X,Y) != 0 and 0 otherwise, so: A corr? B = 1, B corr? C = 1, but A corr? C could be = 0 If corr? was transitive, then A corr? C = 1", "What is the bug about: Keyword gets duplicated even when the query is not modified. Impact: As far as i can tell - cosmetic. How to replicate: Go to: and keep pressing Search button. With each search there will be a duplicate python keyword appended to search box. Best guess for what is causing it: I think you have somewhere a piece of code that appends tag as a keyword without checking if it is already present. My reasoning comes from this url: not having the same issue - the tag is not present in it.", "Variables in batch file not being set when inside IF? I have two examples of very simple batch files: Assigning a value to a variable: @echo off set FOO=1 echo FOO: %FOO% pause echo on Which, as expected, results in: FOO: 1 Press any key to continue . . . However, if I place the same two lines inside an IF NOT DEFINED block: @echo off IF NOT DEFINED BAR ( set FOO=1 echo FOO: %FOO% ) pause echo on This unexpectedly results in: FOO: Press any key to continue . . . This shouldn't have anything to do with the IF, clearly the block is being executed. If I define BAR above the if, only the text from the PAUSE command is displayed, as expected. What gives? Follow up question: Is there any way to enable delayed expansion without setlocal? If I were to call this simple example batch file from inside another, the example sets FOO, but only LOCALLY. For example: testcaller.bat @call test.bat @echo FOO: %FOO% @pause test.bat @setlocal EnableDelayedExpansion @IF NOT DEFINED BAR ( @set FOO=1 @echo FOO: !FOO! ) This displays: FOO: 1 FOO: Press any key to continue . . . In this case, it appears that I have to enable delayed expansion in the CALLER, which may be a hassle.", "Normality of dependent variable = normality of residuals?", "How to test whether a file uses CRLF or LF without modifying it? I need to periodically run a command that ensures that some text files are kept in Linux mode. Unfortunately dos2unix always modifies the file, which would mess file's and folder's timestamps and cause unnecessary writes. The script I write is in Bash, so I'd prefer answers based on Bash." ]

[ "Is there a command to show the directory/file name when cat files? For example: assume two files f1.txt and f2.txt are under ./tmp ./tmp/f1.txt ./tmp/f2.txt Then when I do cat ./tmp/*.txt, only the content of files will be shown. But how to firstly show the file name, then the content?, e.g.: (The needed command): ./tmp/f1.txt: This is from f1.txt and so on ./tmp/f1.txt: This is from f2.txt ... Is there a command to do it? (There seems to be no option for 'cat' to show the file names)", "Choosing my name as an author when publishing a scientific paper, can I use my \"unofficial\" first name? I have one official first name which appears on my ID card. I have another first name which friends call me by. Is it possible to use my unofficial first name and official family name to publish scientific papers? How can I prove to someone that I am one of the authors?", "Hyphen or no hyphen when modifying an adjective with a quantity?", "After upgrading from 10.04 to 12.04 I am trying to install different packages. For instance ia32-libs and skype (4.0). When trying to install these, I am getting the 'Unable to correct problems, you have held broken packages' error message. Output of commands: sudo apt-get install -f Reading package lists... Done Building dependency tree Reading state information... Done 0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded. After running this: sudo dpkg --configure -a foo@foo:~$ sudo apt-get install -f Reading package lists... Done Building dependency tree Reading state information... Done 0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.", "General misconception about $\\sqrt x$", "I need to find a way of proving that the square roots of a finite set of different primes are linearly independent over the field of rationals. I've tried to solve the problem using elementary algebra and also using the theory of field extensions, without success. To prove linear independence of two primes is easy but then my problems arise. I would be very thankful for an answer to this question.", "Laplace transform of $1/t$", "How do I earn SC2's \"Hurry up, it's raid night\" achievement? The \"Hurry up, it's raid night\" achievement in Starcraft 2 involves \"beating Wings of Liberty, on normal, in 8 hours or less.\" Is there a recommended mission path to take? Which mission should I take for the branching paths? Does it count time spent on the Hyperion in between missions, or is it exclusively time elapsed on missions. Does replaying a mission affect the time? General tips / hints from those who've unlocked the achievement? Edit: Just got this achievement tonight, finally! The answer was perfect.", "What is the simplest way of proving (to a non-mathematician) that the power set of the set of natural numbers has the same cardinality as the set of the real numbers, i.e. how to construct a bijection from $\\mathcal{P}(\\mathbb{N})$ to $\\mathbb{R}$?", "Here is the problem: Suppose that $*$ is an associative binary operation on a set $S$. Let $$H:= \\{a \\in S\\mid a * x = x * a \\mbox{ for all }x\\in S\\}.$$ In other words, $H$ is consisting of all the elements of $S$ that commute with every element in $S$. Show that $H$ is closed under $*$.", "Sophomore's dream: $\\int_0^{1} x^{-x} \\; dx = \\sum_{n=1}^\\infty n^{-n}$ In the solution of the so-called , one of the key steps is to compute $$\\int_0^1 x^n (\\log x)^n~\\mathrm dx$$ using the change of variables $x = \\exp\\left(-\\frac{u}{n+1}\\right)$ to obtain the Gamma function. This substitution to me, looks like it was pulled out of thin air. Can someone help me motivate it? How would I have thought of this substitution?", "I have read that a holomorphic function in an open disc has a primitive in that disc. Does this mean that for any holomorphic function $f$ in any open set $U,$ that $f$ has a primitive? I say this because I can take a large enough open disc to cover the open set $U$ and find its primitive there. Is this a correct way of thinking?", "Sum with binomial coefficients: $\\sum_{k=0}^{n}{2n\\choose 2k}$ I'm repeating material for test and I came across the example that I can not do. How to calculate this sum: $\\displaystyle\\sum_{k=0}^{n}{2n\\choose 2k}$?", "Monty hall problem extended. I just learned about the Monty Hall problem and found it quite amazing. So I thought about extending the problem a bit to understand more about it. In this modification of the Monty Hall Problem, instead of three doors, we have four (or maybe $n$) doors, one with a car and the other three (or $n-1$) with a goat each (I want the car). We need to choose any one of the doors. After we have chosen the door, Monty deliberately reveals one of the doors that has a goat and asks us if we wish to change our choice. So should we switch the door we have chosen, or does it not matter if we switch or stay with our choice? It would be even better if we knew the probability of winning upon switching given that Monty opens $k$ doors.", "First off, here is some code: int main() { int days[] = {1,2,3,4,5}; int *ptr = days; printf(\"%u\\n\", sizeof(days)); printf(\"%u\\n\", sizeof(ptr)); return 0; } Is there a way to find out the size of the array that ptr is pointing to (instead of just giving its size, which is four bytes on a 32-bit system)?", "How to determine the amount of experience needed for leveling up Related questions under this topic might include: How should I base how much experience points it takes to get to the next level? What factors are involved in this? How do I keep the player not entertained long enough till he levels up? How can I vary the way the player gets experience points?", "(Before anyone jumps to the conclusion that this is the same question as , please read it through. Also I am looking for more comprehensive and detailed data than the poster in .) Many years ago I used to use a tool called Line Speed Meter (or Monitor) by TCPIQ. This was a brilliant piece of software that would sit quietly in the background and several times a day (according to a selectable frequency) would reach out and test internet line performance against servers all over the world. In the course of a week (or more), thousands of servers would be tested and enough data would accumulate that one could analyze performance according to time of day, day of week, location of server, etc. Drill-down was possible to the point where you could see every server that was tested. This data was invaluable in determining if one really was getting the performance being paid for. It was also infinitely more valuable than spot checks you perform at sites like or even the better-regarded ones like or (both of which, incidentally, are biased toward USA users - which I am not one of anymore). Unfortunately Line Speed Meter is no longer supported and the company that made it now has instead a tool called isposure that is nowhere near as flexible or transparent - it is geared to supplying data to ISPs rather than to the consumers. For example, according to their FAQ, it usually runs only once a day automatically - I'd like to start with running it every couple of hours for a week or two - and scale back once I have a good basis so that I can notice when performance changes. Also, the details of the tests are no longer visible to the consumer-user. My question: is there a (preferably free) tool/service available today to automatically collect comprehensive line speed metrics so I can map out and analyze the performance I am getting on my Broadband internet connection? EDIT 2012-02-13: I left something out of the above. In my country, each ISP sells a package that implies performance beyond the borders of my small country. They own (or lease) the lines going across the ocean. They have full control of the bandwidth leading from their servers to the backbones in the USA and EU. Peformance through the cloud is very much relevant and although not entirely, certainly largely under the local ISP's control, since traditionally, the bottleneck has been traffic out of the country. As an example, at the moment, my ISP is advertising widely their new transatlantic cable and how their performance now outstrips everyone else's. I haven't \"felt\" it - so I want a tool to quantify it. Performance within my country is usually good. The problem is that almost all my work involves access to the Internet in North America, Europe, Pacific Rim and others. So I care about and want to document the end-to-end performance I am getting from my ISP - and if I switch, compare to what I get at a new ISP. EDIT 2013-03-07: As @harrymc pointed out I neglected to mention OS. All the machines on my home LAN are (sadly) Windows (XP or 7). If A tool requires *nix, I have a couple ancient machines in storage I could probably re-purpose - but my preference is for a Windows-based tool. Thanks. EDIT 2013-03-10: As a further clarification - a method to monitor speeds achieved during regular work provides half of what I'm looking for. What was nice about TCPIQ is that it would ferret out thousands of sites around the world and do brief d/l &amp; u/l tests against them to check speed and then log the results. This gave a valuable statistical database for analysis of speed overall, as well as during times of day, days of week and according to geographical targets. That's the sort of functionality I'd like to achieve (again).", "Assume $f:\\mathbb R\\rightarrow {\\mathbb R} $ is Lebesgue integrable, prove $\\sum_{n\\in\\mathbb N } f(x+n)$ converges for almost everywhere x. This is a question discussed with friends. Thanks", "According to , the SE chat sites may have individual Easter eggs, depending on the site. If you find them, please post. Because it's so easy to make this stuff up, a screenshot as proof would be nice. (Although Photoshop isn't that hard either...)", "How to saveHTML of DOMDocument without HTML wrapper?" ]

[ "The says that there is a moderator election occurring. How does the election work and how can I get involved?", "Non-standard signature of main() compiles successfully", "Topologist's sine curve is not path-connected", "Should student or supervisor be corresponding author for publications based on student research? Papers published from an academic project (MSc or PhD) usually have two authors; the first author is the student who mainly conducted the research, and the second author is the professor who supervised the projects. The corresponding author is the one who take the responsibility of a paper, and thus, some believe that students are not yet prepared to take this responsibility. Ideally, who should be corresponding author for papers published by MSc or PhD projects? I understand that it mainly depends on personal agreements and preferences, but I want to know which case is more reasonable from academic logic?", "I have seen people showing one slide progressively by pressing Enter. Could anyone tell me how to realize that in Beamer?", "I'm trying to generate a secret key to be used for HMAC SHA-256 signature processing. I've seen many sample of keys with variable length from 32 characters to 96 characters. What is the ironclad rule for this key size?", "Finite Sum $\\sum\\limits_{k=1}^{m-1}\\frac{1}{\\sin^2\\frac{k\\pi}{m}}$", "Using --exclude with the du command This is probably something basic but I'm not able to make it work. I'm trying to use DU to get a total size of files minus certain directories. I need to exclude one specific directory called uploads but not every directory called uploads. For example, my file structure looks a bit like this: /store /uploads /junk_to_ignore /more_junk_to_ignore /user_one /uploads /user_two I can run the following command: du -ch --exclude=uploads* and it gives me the file size minus all the \"uploads\" directories. However, in trying to exclude certain directories (and all its sub-directories) I fail. I've tried variations of: du -ch --exclude=./uploads* du -ch --exclude='/full/path/to/uploads/*' but can't seem to figure it out. How do I exclude a specific directory?", "Singular or plural following a list", "Volume generated by revolving the region in the first quadrant bounded by the parabolas $y^2=x$, $y^2=8x$, $x^2=y$, $x^2=8y$ about the $x$-axis. I came across this question from Schaum's Outlines of Advanced Calculus: Show that the volume generated by revolving the region in the first quadrant bounded by the parabolas $y^2=x$, $y^2=8x$, $x^2=y$, $x^2=8y$ about the $x$-axis is $\\dfrac{279\\pi}{2}$. My solution was to divide the region into three parts: $$\\pi\\int_{1}^{2}(x^2)^2 - (\\sqrt{x})^2\\;dx = 4.7\\pi$$ $$\\pi\\int_{4}^{8}(\\sqrt{8x})^2 - (\\sqrt{x})^2\\;dx = 42\\pi$$ $$\\pi\\int_{2}^{4} (x^2)^2 - \\left(\\frac{1}{8}x^2 \\right)^2\\;dx = 44.9\\pi.$$ Hence the total volume will be $$\\pi(4.7 + 42 + 44.9) = 91.6\\pi$$ which is wrong. Can someone point out my mistake?", "Adding new ROLES and USERS through REST in GeoServer I use GeoServer stable version 2.14.1 and get error messages when trying to add new roles and users via REST. I suspect that the GeoServer REST documentation is buggy. When I call the REST interface of my GeoServer instance, I can see that the roles are accessible through the URI http://localhost:8080/geoserver/rest/security/roles. Users are under the URI http://localhost:8080/geoserver/rest/security/usergroup/users. I can query both resources via GET request, but adding new resources via POST or PUT will not work. A POST request to create new roles ends up with status code 405 (Method not allowed). After trying to create new users comes the status code 500 (Internal Server Error). For this, the GeoServer-REST documentation has been referencing the paths /roles/roles/{role} for new roles () or /usergroup/users/ for new users () since several GeoServer versions. But when I use them, this always ends with Status code 404 (Not Found). How can I add new roles and users through REST in GeoServer? The workarround from @implssv in does not work for me.", "Prove $a^\\alpha b^{1-\\alpha} \\le \\alpha a + (1 - \\alpha)b, \\; a,b > 0,\\; 0 < \\alpha < 1$ I have no idea how to do this. Any help would be appreciated. The chapter I'm on is about differentiation and the mean value theorem. Prove $a^\\alpha b^{1-\\alpha} \\le \\alpha a + (1 - \\alpha)b, \\; a,b &gt; 0,\\; 0 &lt; \\alpha &lt; 1$", "When, where and **how often** do you find polynomials of higher degrees than two in mathematical, pure/applied, research? A formula for solving a polynomial of degree three, see link; $ax^3+bx^2+cx+d=0$, is $$\\begin{align} x\\quad&amp;=\\quad \\sqrt[3]{ \\left( \\frac{-b^3}{27a^3} + \\frac{bc}{6a^2} - \\frac{d}{2a} \\right) + \\sqrt{ \\left( \\frac{-b^3}{27a^3} + \\frac{bc}{6a^2} - \\frac{d}{2a} \\right) ^2 + \\left( \\frac{c}{3a} - \\frac{b^2}{9a^2} \\right) ^3 } }\\\\ &amp;+\\quad \\sqrt[3]{ \\left( \\frac{-b^3}{27a^3} + \\frac{bc}{6a^2} - \\frac{d}{2a} \\right) - \\sqrt{ \\left( \\frac{-b^3}{27a^3} + \\frac{bc}{6a^2} - \\frac{d}{2a} \\right) ^2 + \\left( \\frac{c}{3a} - \\frac{b^2}{9a^2} \\right) ^3 } } \\;-\\;\\frac{b}{3a} \\end{align}$$ Unlike quadratic, cubic, and quartic polynomials, the general quintic cannot be solved algebraically in terms of a finite number of additions, subtractions, multiplications, divisions, and root extractions, as rigorously demonstrated by Abel (Abel's impossibility theorem) and Galois. However, certain classes of quintic equations can be solved [...] Source: At levels of $5^{\\text{th}}$ degree polynomials, things are starting to look really serious in my eyes. My question is: If it is possible to not answer subjectively: When, where and how often do you find polynomials of higher degrees than two in mathematical, pure/applied, research?", "I don't understand philosophy very well, and so I am wondering whether you can \"prove\" anything in philosophy. It always seems you can go a layer down, and find another question, almost endlessly until you get to the question of \"why/how/are we here?\" Can you prove, absolutely, and 100% that something is true, in the field of philosophy?", "Maybe I'm searching for the wrong thing, but I can't see how I can do this. I have two servers: Server A (has SQL Server 2012 installed) Server B (has SQL Server 2014 installed) Server A provides an API via IIS. The code both inserts and gets data from the database depending on the API call. Server B does exactly the same for its local database. I would like to have it so that the two databases are consistent copies of each other. I do believe this is what HA accomplishes. So a load balancer, for example, might direct API calls to A sometimes, and B sometimes, but the data needs to be consistent either way. I found some documentation on HA for SQL Server 2012, but not on how to do this for a mixed environment of 2012 and 2014. Any help or pointers to documentation would be great! Thanks.", "How do I capture the milky way? Can the milky way actually be photographed ? I know the image is manipulated, and is probably a composite, but how do you capture such contrast in the milky way? Is an equitorially mounted scope required? Any advice or pointers are welcome, thanks. I'm heading out towards much less light polluted areas middle of next week and I want to try some nighttime sky captures with my 7D. Additional info: I just found on wikipedia that says: 54s, tripod mounted 5D, 16mm lens, f/2.8, ISO800. What else do I need to be aware of? My 7D is only an APS-C and the widest lens I have is 19mm. I'm thinking that might not be wide enough to capture an interesting shot?", "options for appearance of links in hyperref", "Automatically show which tags were edited in revision history I’ve developed the habit of using the revision summary to indicate which changes I’ve made to the tags while retagging a question. For instance, if the question originally had tags and it should be instead, I write the following in the revision summary: Edited tags: -cocoa, -touch, +cocoa-touch which I find useful (and potentially educational) for the OP and other editors. On the other hand, when an editor doesn’t type a revision summary, Stack Overflow shows User (timestamp) edited tags with no indication of the difference between previous tags and the tags set by that edit. Since there’s a limit on the number of tags, this difference would easily fit in the revision history list of that question. Could this be automatic in case the editor doesn’t fill the revision summary? Is it worth it?", "datetime conversion to CDT Can anyone please help me how to convert the given time into CST timezone. Input timezone will change dynamically, so i want to convert the given timzone into CST and then need to get the hour from that CST timezone in apex.", "CAST and IsNumeric Why would the following query return \"Error converting data type varchar to bigint\"? Doesn't IsNumeric make the CAST safe? I've tried every numeric datatype in the cast and get the same \"Error converting...\" error. I don't believe the size of the resulting number is a problem because overflow is a different error. The interesting thing is, in management studio, the results actually show up in the results pane for a split second before the error comes back. SELECT CAST(myVarcharColumn AS bigint) FROM myTable WHERE IsNumeric(myVarcharColumn) = 1 AND myVarcharColumn IS NOT NULL GROUP BY myVarcharColumn Any thoughts?" ]

[ "Convert a number to a string with specified length in C++", "Finding the error in this proof that 1=2 I have a \"proof\" that has an error in it and my goal is to figure out what this error is. The proof: If $x = y$, then $$ \\begin{eqnarray} x^2 &amp;=&amp; xy \\nonumber \\\\ x^2 - y^2 &amp;=&amp; xy - y^2 \\nonumber \\\\ (x + y)(x - y) &amp;=&amp; y(x-y) \\nonumber \\\\ x + y &amp;=&amp; y \\nonumber \\\\ 2y &amp;=&amp; y \\nonumber \\\\ 2 &amp;=&amp; 1 \\end{eqnarray} $$ My best guess is that the error starts with the line $2y = y$. If we accept that $x + y = y$ is true, then $$ \\begin{eqnarray} x + y &amp;=&amp; y \\\\ x &amp;=&amp; y - y \\\\ x &amp;=&amp; y = 0 \\end{eqnarray} $$ Did I find the error? If not, am I close?", "How to get the file name from a full path using JavaScript? Is there a way that I can get the last value (based on the '\\' symbol) from a full path? Example: C:\\Documents and Settings\\img\\recycled log.jpg With this case, I just want to get recycled log.jpg from the full path in JavaScript.", "Why do people sometimes use the past perfect form of a verb when the past would suffice? (e.g. \"you had mentioned\") I noticed that my American friends tend to use the past perfect form when they use the verb mention in its past form, almost despite of the context of the sentence. I hear them say \"you had mentioned\" a lot more often even in situations where the use of simple past would have been perfectly fine. Have you noticed it too and is it one of those unwritten rules, or is there a more formal explanation to it? It seems like there was more verbs like that, but I am having a hard time remembering it now. If I do, I will edit the post and likely change the title to accommodate other verbs.", "bash dynamic (variable) variable names", "I don't want to use the Super for that, I want to use Alt+Space instead.", "A way for \"new users\" to ask about their post specifically We currently require that new users have 5+ reputation to participate in meta support discussions (bugs, feedback, governance, etc). This is primarily because the use case for meta is not intrinsically obvious, so we require a modicum of \"experience\" with the site before jumping into it. But that blocks new users with legitimate questions about their own posts. Setting aside any arguments about new-users-are-evil-and-suck-the-life-out-of-our-community, I would like to propose a very specific path for new users to ask about their own question provisionally. Instead of blocking a new user with this message: You must have at least 5 reputation on &lt;site> to ask a question on meta. We can change this to: You must have at least 5 reputation on &lt;site> to post on meta, but you may ask a question about your own post specifically. Link to your post: &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; ask about this post cancel The system will check whether the linked question provided belongs to the author. . The user can then proceed with the post provided they leave the template (below) intact: Title &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &nbsp; &lt;!--Do not remove--> &lt;!--Note: Questions not about your post will be deleted--> I have a question about the post: &lt;!-- Your question below: --> &nbsp; Not only is this a great and gentle introduction to the proper use of meta, but it stands to help new users just when they need it most (learning to use the community). Of course this doesn't 100% guarantee that someone won't get it wrong on occasion. But this is an awful lot of in-your-face guidance without simply telling people \"read our FAQ\" (which they never do). And if a user manages to step over all that guidance and still manages to misuse meta, I have no compunction about summarily removing a question they should never have posted. But this just-in-time learning is a very effective way of learning a new site in a gentle and thoughtful way. If this is abused more often than not, it is easy to disable. But it's better than assuming clueless newbie every time.", "Using R, I have fitted a linear model for a single response variable from a mix of continuous and discrete predictors. This is uber-basic, but I'm having trouble grasping how a coefficient for a discrete factor works. Concept: Obviously, the coefficient of the continuous variable 'x' is applied in the form y = coefx(varx) + intercept but how does that work for a factor z if the factor is non-numeric? y = coefx(varx) + coefz(factorz???) + intercept Specific: I have fitted a model in R as lm(log(c) ~ log(d) + h + a + f + h:a) where h and f are discrete, non-numeric factors. The coefficients are: Coefficients: Estimate (Intercept) -0.679695 log(d) 1.791294 h1 0.870735 h2 -0.447570 h3 0.542033 a 0.037362 f1 -0.588362 f2 0.816825 f3 0.534440 h1:a -0.085658 h2:a -0.034970 h3:a -0.040637 How do I use these to create the predictive equation: log(c) = 1.791294(log(d)) + 0.037362(a) + h??? + f???? + h:a???? + -0.679695 Or am I doing it wrong? I THINK that that concept is if the subject falls in category h1 and f2, the equation becomes: log(c) = 1.791294(log(d)) + 0.037362(a) + 0.870735 + 0.816825 + h:a???? + -0.679695 But I'm really not clear on how the h:a interactive term gets parsed. Thanks for going easy on me.", "Use early 2009 20\" iMac as external display for 2015 rMBP", "With regards to post about and the part about retaining reputation earned from deleted posts that have a score of 3 or better and were visible on the site for 60 days, does this also apply to self-deleted posts and will it continue to do so? I culled a few of my own answers over the weekend that were less than stellar, and my reputation dropped 1.8k, but the rep is back today after the changes were announced. I thought it would be useful to clarify that this also applies to self-deleted stuff.", "As i am new to blender i decided to learn by recreating some animations which have some interesting problems, and gain more knowledge about how tv intros are being done, collecting some parody intros to videos. I came across a simple yet troublesome effect , found no answer by googling or getting through tutorials and testing methods on this case led me to nowhere. I attempted to recreate the animation above, especially the extending/appearing/drawn white strip with \"randomly\" placed gaps , strip which travels just above surface , casting shadow. Tried dynamic paint,( with alpha channel) image sequence texture but although effect was very similar, whole invisible strip was casting shadow being Z transparent, in places where white color haven't reached yet. I tried bezier curves as well(vector mode) but it appears that taper cant profile part in squary way, or maybe i am missing something here. Shape keys seem to hard way to go , while keeping whole animation of stripe \"unrolling\" at constant speed. I tried as well putting an array of planes on the path but it is completely not what i attempt to achieved. I will edit post and add some pictures tomorrow.", "I've installed Ubuntu 16.04 on my Asus X555LJ. But I don't know how to install drivers or how to enable function keys to controls screen backlight brightness.", "Recover accidentally removed files on NTFS partition I accidentally removed some files on a NTFS partition How can I recover them staying inside Linux without rebooting ?", "Hartshorne Theorem 8.17", "I am in doubt as to whether the subject-verb agreement of the second sentence of this paragraph is correct : Unfortunately, there is no such thing as the ideal home workshop because most people are limited by the space available and by their budget. However, the information and diagram here acts as a guide to help you formulate a sensible workshop layout and a machinery “wish list”. I suppose if the compound subject is seen as a single unit, then the sentence can be considered as correct. A little further in the same book, another sentence has a singular verb with a compound subject : Alternatively commandeer a garage, or build yourself a substantial workshop if outdoor space and permission allows – however, do consider the impact of machinery noise on your neighbours. Can &quot;outdoor space and permission&quot; be seen as one thing, or would this be considered a mistake ?", "Use 'import module' or 'from module import'?", "Reading a 5 Band resistor with Gold as a middle band? Can anyone read the resistor that the arrow is pointing to? From what I know you can not have a gold band as a number and if I am reading it correctly it has a tolerance of 0 which does not seem right.", "Automatically change é to \\'e – most convenient setup for accented letters? I assume this is really basic question, I'm new to LaTeX, I read a first step tutorial to get ready to write some documents but I couldn't answer my own question at this time and I really don't know where to search. When I try to write é and compile my document, this character is not shown. I know the sequence is \\'e to make it happen in the document but that is really disturbing to write. Is there someway to write a paragraph \"normally\" and convert all the special chars into the LaTeX syntax? Or is there a way to allow é, à, ... writing so the compilation includes them into the document?", "Creating centerline from lines using QGIS How do I create a centerline (vector data) from two parallel polylines (vector data) in QGIS? For example, if the distances between two parallel lines are 14m, then I want to create a centerline at 7m from both lines.", "Time Dilation When In Orbit Imagine a space ship orbiting the sun at near relativistic speeds, when compared to Earth (say from the reference frame of the sun) there would be x amount of time dilation. This would mean people on the ship could live for 100's of Earth years. My question is what would happen if a second ship flew directly away from the Sun and back (ignoring acceleration) at the same speed the orbiting ship is travelling, would the time dilation for the ship that travels in a straight line be the same as that moving in a circle? The reason I ask is that I was imagining a scenario where intergalactic travel is possible as time dilation means even a journey of light years only ages the crew a fraction of that time, with space stations orbiting certain star systems at similar speeds so that people that don't work on ships can live a similar length of time. I understand that time dilation is all linked to a certain reference frame but working with a reference frame of the sun what would the time dilation be for the different objects taking different paths but at the same speed relative to the sun? If the ship docked back with the space station would they both say the same amount of time had passed?" ]

[ "Prove the map has a fixed point Assume $K$ is a compact metric space with metric $\\rho$ and $A$ is a map from $K$ to $K$ such that $\\rho (Ax,Ay) &lt; \\rho(x,y)$ for $x\\neq y$. Prove A have a unique fixed point in $K$. The uniqueness is easy. My problem is to show that there a exist fixed point. $K$ is compact, so every sequence has convergent subsequence. Construct a sequence ${x_n}$ by $x_{n+1}=Ax_{n}$,$\\{x_n\\}$ has a convergent subsequence $\\{ x_{n_k}\\}$, but how to show there is a fixed point using $\\rho (Ax,Ay) &lt; \\rho(x,y)$?", "From Stewart 7e pg 614 # 9 \"One model for the spread of a rumor is that the rate of spread is proportional to the product of the fraction y of the population who have heard th eremor and the fraction who have not hear the rumor. a) Write a differential equation that is satisfied by y. b) Solve the differential equation c) A small town has 1000 inhabitants. At 8 am 80 people have heard a rumor. By noon half the town has heard it. At what will 90 percent of the population have heard the rumor? \" The wording of this is very ambiguous to me and I can't really make sense of it. They mention a product, so I know that something is being multiplied and that y is a fraction which belongs to the population who have seen it so I think that \"have not\" heard is a constant, and that y is a fraction taht represents who have. I tried to set this up and it is the wrong answer. I am not sure what they want from that, the English usage is too ambiguous to make sense of it. The complete lack of punctuation is what really does it.", "Rounded corner shape with rounded sides", "I am trying to make a histogram with the fitted curve plotted on it. Here's the mwe: \\documentclass[a4paper]{scrartcl} \\usepackage{tikz} \\usepackage{pgfplots,pgfplotstable} \\usepackage{filecontents} \\pgfplotsset{compat=1.10} \\usepackage[active,tightpage]{preview} \\setlength\\PreviewBorder{2pt} \\newcommand{\\plots}{0.611201} \\newcommand{\\plotm}{2.19882} \\begin{filecontents}{data.dat} 2 0.0629921259843 3 0.0236220472441 4 0.0314960629921 5 0.125984251969 6 0.0629921259843 7 0.102362204724 8 0.110236220472 9 0.0551181102362 10 0.0629921259843 11 0.0314960629921 12 0.0236220472441 13 0.0314960629921 14 0.0629921259843 15 0.0551181102362 16 0.0393700787402 17 0.0472440944882 18 0.00787401574803 19 0.0393700787402 24 0.00787401574803 27 0.00787401574803 33 0.00787401574803 \\end{filecontents} \\begin{document} \\begin{preview} \\begin{tikzpicture} \\begin{axis}[ yticklabel style={/pgf/number format/fixed}, scaled y ticks = false, minor y tick num={1}, xtick pos=left, legend cell align = left, legend style={draw=none}, xlabel = {group size}, ylabel = {ratio} ] \\addplot[blue,ybar,fill, fill opacity=0.3, bar width = 0.8,] table {data.dat}; \\addplot[red, line width = 1,domain=1:40,samples=100] {1/(x*sqrt(2*pi)*\\plots)*exp(-(ln(x)-\\plotm)^2/(2*\\plots^2))}; \\legend{empirical,lognormal fit} \\end{axis} \\end{tikzpicture} \\end{preview} \\end{document} As you can see, the legend is not really good. How can I change the legend so it looks more like this?", "How can I edit this trigger to only fire once? The trigger creates a related record when a checkbox is updated. The problem is it is creating a new related record everytime the record is edited. I want to edit the trigger to only create the related record once. (When the criteria is first met). The code is below Trigger copyEquipmentonsite on Unit_Placements_Sales__c(after insert, after update) { List&lt;Services__c&gt; sub=new List&lt;Services__c&gt;(); for(Unit_Placements_Sales__c u : Trigger.new) { if(u.Service_Month_is_Next_Month__c == TRUE) { Services__c s = new Services__c(); s.Equipment_Onsite__c=u.ID; s.Equipment_Type__c=u.Equipment__c; s.Machine_Specific_Notes__c=u.Machine_Specific_Notes__c; s.Product__c=u.The_Product__c; s.Dell_Tag_Number__c=u.Dell_Tag_Number__c; s.Serial_Number__c=u.Serial_Number__c; s.XD_Number__c=u.XD_Number__c; sub.add(s); } if(sub.size()&gt;0) insert sub; } }", "Can I downgrade to an earlier version of Android after installing an OTA update? I installed the KitKat upgrade on my Nexus 7, but I am unhappy with it. Is it possible to roll back to an earlier version of Android (Jelly Bean)?", "How can I make a gameObject \"stick\" to another gameObject after it has collided with it? How can I make a gameObject \"stick\" to another gameObject after it has collided with it? Right now the gameObject just passes through! [C#]", "Long boot delay on Ubuntu loading/splash screen following regular dist-upgrade on clean SSD install (18.04)", "Escaping WP_Query tax_query when term has special character(s) Here's my issue. I have a custom post type that I'm attaching a custom taxonomy to. This taxonomy will allow the admin to provide search suggestions that will ensure the post is found when a user searches. This taxonomy is also used on the front-end to autocomplete the search field with these suggestions. The system works fine, except when the term contains a forward slash, a space or other \"special\" characters. &lt;?php $keyword = 'Ski-in%2FSki-out';//Submitted via $_GET $keyword = urldecode($keyword); // (string)'Ski-in/Ski-out' $taxQuery = new WP_Query(array( 'post_type' =&gt; 'ml_properties', 'tax_query' =&gt; array( 'relation' =&gt; 'OR', array( 'taxonomy' =&gt; 'mc_tax_lifestyle', 'field' =&gt; 'name', 'terms' =&gt; array($keyword), 'operator' =&gt; 'IN' ) ) )); ?&gt; I've looked into using the escaping features provided by WordPress, but haven't had any luck there. I thought this would be a simple problem, but either my Google-fu is not strong, or I'm just not having any luck. I've also verified that that Ski-in/Ski-out is the exact string stored in MySQL. I've looked into using esc_attr(), $wpdb-&gt;esc_like() and esc_sql() but none have an effect. Perhaps I'm missing something obvious?", "$H_0(X,A) = 0 \\iff A \\cap X_i \\neq \\emptyset \\forall $ path-components $X_i$ I've been doing some more exercises in , in particular the following: Show that $H_0(X,A) = 0$ iff $A$ meets each path-component of $X$. \"$\\Leftarrow$\": Let $x_i \\in A \\cap X_i \\neq \\emptyset \\forall $ path-components $X_i$. Then for any $x \\in X_i$ there is a path $\\gamma$ from $x_i$ to $x$. They therefore differ by a boundary: $\\partial \\gamma = x - x_i$ and therefore $\\{&#160;x \\} = \\{ x_i \\}$ in $H_0(X,A) $. Therefore $H_0(X,A) = 0$. \"$\\Rightarrow$\" Now for this direction I'm not so sure and I'd be glad if you could give me a hint. Let $H_0(X,A) = 0$. By definition, the relative homology group is calculated from the following sequence of chain groups: $$ 0 \\rightarrow C_0(A) \\rightarrow C_0(X) \\xrightarrow{\\partial_1} C_0(X) / C_0(A) \\xrightarrow{\\partial_0} 0$$ Then $H_0(X, A) = H_0(C_0(X) / C_0(A)) = ker \\partial_0 / im \\partial_0 = (C_0(X) / C_0(A) ) / im \\partial_1 = 0$. There are two cases where this equality holds: (i) $C_0(X) / C_0(A) = 0$ (ii) $im \\partial_1 = C_0(X) / C_0(A)$ In case (i), $A \\cap X_i \\neq \\emptyset$ for all $X_i$. In case (ii) I'm not sure how to proceed. Can you give me a hint? Many thanks for your help! Edit Or maybe I could do the second direction like this: $$0 = H_0(X,A) = \\oplus_i H_0(X_i, A) \\implies H_0(X_i, A) = 0 \\forall i$$ $$ \\implies A \\cap X_i \\neq \\emptyset \\forall i$$?", "Possible Duplicate: The FAQ specifies that: Use your downvotes whenever you encounter an egregiously sloppy, no-effort-expended post, or an answer that is clearly and perhaps dangerously incorrect. But if I find a correct question, closed (or not yet) as duplicate, is downvote a correct behavior for Stack&nbsp;Overflow policy?", "How did the English language come to this? The play was awful. Is the complete opposite of The play was awesome. But if you break it down to awe followed by ful or some, it doesn't make sense at all. Can someone shed a light on this? Is there a rule to this, or is it one of those things you need to just memorize?", "Suppose that $X$ and $Y$ are chosen randomly and independently according to the uniform distribution from $(0,1)$. Define $$ Z=\\frac{\\max(X,Y)}{\\min(X,Y)}.$$ Compute the probability distribution function of $Z$. Can anyone give me some hints on how to proceed? I can only note that $\\mathbb{P}[Z\\geq 1]=1$ and $$F_Z(t)= \\mathbb{P}[Z \\leq t]=\\mathbb{P}[X\\leq Y, Y\\leq tX]+\\mathbb{P}[Y \\leq X, x\\leq tY]$$", "How to use GROUP BY to concatenate strings in SQL Server?", "I'm looking for a way to insert a &lt;style&gt; tag into an HTML page with JavaScript. The best way I found so far: var divNode = document.createElement(\"div\"); divNode.innerHTML = \"&lt;br&gt;&lt;style&gt;h1 { background: red; }&lt;/style&gt;\"; document.body.appendChild(divNode); This works in Firefox, Opera and Internet Explorer but not in Google Chrome. Also it's a bit ugly with the &lt;br&gt; in front for IE. Does anyone know of a way to create a &lt;style&gt; tag that Is nicer Works with Chrome? Or maybe This is a non-standard thing I should avoid Three working browsers are great and who uses Chrome anyway?", "Unupvote immediately followed by an upvote gives me a net -10 reputation points", "Rotating clears selected tags Changing the orientation of your device within the tag selection view while asking a question removes all selected tags and clears the textbox. Steps to reproduce: Ask a question (does not happen when editing) Edit tags Enter some text in the box Select a tag from the suggestion list Repeat the previous two steps as many times as you care to Rotate the device (source / target orientation doesn't matter, just need to change it) All selected tags and text typed in the textbox are gone and must be re-entered I've reproduced this using version 1.0.63 of the SE app on two devices: HTC One E8 m2ss (the Hong Kong version) rooted and running stock 5.0.2 ATT Galaxy S3 i747, rooted and sim unlocked, running Slimkat 4.4.2.build.4.1.official ROM on Android 4.4.2", "How do I install Guest Additions in a VirtualBox VM?", "How can I delete an email address from Outlook's email history?", "I have heard many (rather most) people, especially in the USA, saying: I don't know nothing about it. Is that correct? I always get a weird feeling hearing this and feel the correct one would be saying: I don't know anything about it." ]

[ "dpkg: error processing package mysql-server (--configure)", "Confused about complex numbers I am confused about something: \\begin{eqnarray} (e^{2 i \\pi})^{0.5} = (e^{2 i \\pi \\cdot 0.5})= e^{i \\pi}=-1 \\end{eqnarray} but \\begin{eqnarray} e^{2 i \\pi}=1~ and~ 1^{0.5}=1 \\end{eqnarray} where is my mistake?? thanks", "Spoilers for A Storm of Swords / Season 4 episode 2 \"The Lion and the Rose\". At the Purple Wedding, Littlefinger and Lady Olenna Tyrell perform their plan of poisoning King Joffrey. A short summary of their plan: Littlefinger orders Ser Dontos Hollard to give Sansa Stark a beautiful silver hairnet adorned with amethysts. At least some of the amethysts are actually strangler crystals in disguise. Ser Dontos also, still under orders of Littlefinger, urges Sansa to wear the hairnet at the wedding, which she then does. At the wedding, when Lady Olenna greets Sansa, she fusses her hairnet a bit, while secretly taking one of the strangler crystals. Later, during the wedding, Lady Olenna puts the crystal in Joffrey's royal cup, poisoning him. But why was their plan so complicated? Why couldn't Lady Olenna just bring a strangler crystal with her to the wedding (as suggested in )? Then they wouldn't depend on Ser Dontos and Sansa who could unknowingly have done something to prevent the success of the plan. The only reason that I could think of, is Littlefinger and Lady Olenna plan for Sansa (and Tyrion as her husband with her) to take the blame for Joffrey's death. They put the crystals on her person, so that upon examination it would clearly show that Sansa had the murder weapon on her. But Littlefinger had a plan he did not tell Lady Olenna, namely rescuing Sansa during the chaos ensuing the murder (and thereby leaving Tyrion behind as the only accused). Is there anything confirming or debunking this theory? If my theory doesn't hold up, is there another explanation for why the plan was so needlessly complicated?", "I frequently find myself writing code like this: List&lt;int&gt; list = new List&lt;int&gt; { 1, 3, 5 }; foreach (int i in list) { Console.Write(\"{0}\\t\", i.ToString()); } Console.WriteLine(); Better would be something like this: List&lt;int&gt; list = new List&lt;int&gt; { 1, 3, 5 }; Console.WriteLine(\"{0}\\t\", list); I suspect there's some clever way of doing this, but I don't see it. Does anybody have a better solution than the first block?", "ANOVA analysis with only mean and standard deviation", "Processor: PIC18F66K22 Compiler: C18 (XC8 is fine also) I've just made (and succesfully tested) code to measure the voltage on AN4 analog pin. Now I want to try something else, not quite sure if it's theoretically possible. My test-board has a PIC processor, with VDD,AVVD connected to a supply (ranging from 0(if the battery is empty/disconnected) to 4,2(full battery). Can I use ADC to measure the VDD(-in) of my board? Why not?: It's not an ANx pin, not sure how to make the ADC measure it? (Channel?) If the voltage on VDD(-in) drops, will my ADC reference voltage also drop? (So when my PIC only gets 3,3V the ADC will still say it's 100% (as the max Voltage on the chip, also the reference is 3,3V). Why/what do you ask?: Can I just measure Channel 30 (VDDCORE)? Could I set my Vref to Vdd and measure a precision voltage reference with the A/D converter. (Not sure how) Or I could add a wire from VDD-in to an ANx pin? Will Internal VREF+ (4.096V) stay 4+V when the VDD-in is around 3,4V? Is there some kind of transformator that makes it so? Internal VREF+ (4.096V) is a bit lower than the max of the battery (4,2V), does this mean I can damage the ADC? Or just that the result will be max when the battery is full. (4,2V out of 4,096V) Please mind that my knowledge of Electronics is \"low\". I've learnt way more about the software part in my education, but I'd like to know more about (Embedded) Electronics as it's a crucial part in Embedded Engineering. (It's sad how my school doesn't see this.)", "What happens to matter in a standard model with zero Higgs VEV?", "Tentative definitions in C and linking", "How do I create a partially transparent flag?", "Is it costly to do array.length or list.count in a loop I know that in JavaScript, creating a for loop like this: for(int i = 0; i &lt; arr.length; i++) is costly as it computes the array length each time. Is this behavior costly in c# for lists and arrays as well. Or at compile-time is it optimized? Also what about other languages such as Java, how is this handled?", "How can install Desktop Toggl on Ubuntu 13.04? I try type: sudo add-apt-repository ppa:official-toggl/ppa sudo apt-get update sudo apt-get install desktop-Toggl But getting information desktop-Toggl not found.", "How can I obtain the command line arguments of another process? Using static functions of the System.Diagnostics.Process class I can obtain a list of running processes, e.g. by name: Process[] processList = Process.GetProcessesByName(processName); However, there is no way to access the command line used to start this process. How would one do that?", "Show Previous/Next Posts navigation only inside the same category Is it possible to force previous/next navigation to browse through the posts (back and forth) that are only inside the same category (and to exclude other categories)?", "Show that a holomorphic function satisfying $|f(z)|\\leq c|z|^n$ must be $f(z)=a\\cdot z^n$ for some a. Let $f:\\mathbb{C}\\to\\mathbb{C}$ be a holomorphic function such there exists a $c\\in\\mathbb C$ with $|f(z)|\\leq c\\cdot |z|^n$ for all $z\\in\\mathbb C$. Show that there exists an $a\\in\\mathbb C$ with $f(z)=a\\cdot z^n$. Proof. My general idea is to show that the taylor series only has one non-zero coefficient: $\\displaystyle |a_k|\\leq\\frac{k!}{2\\pi}\\oint_{|w|=r}\\frac{|f(w)|}{|w|^{k+1}}dw\\leq \\frac{k!}{2\\pi}\\oint_{|w|=r}\\frac{c\\cdot|w|^n}{|w|^{k+1}}dw\\leq \\\\\\displaystyle\\leq \\frac{c\\cdot k!}{2\\pi}\\oint_{|w|=r}|w|^{n-k-1}dw$ Now using the standard estimate since $\\oint=2\\pi r$: $\\displaystyle \\leq c\\cdot k!\\cdot r^{n-k}\\longrightarrow\\begin{cases}0,\\ k&gt;n\\\\c\\cdot n!,\\ k=n\\\\ \\infty,\\ k&lt;n\\end{cases}$ as $r\\to\\infty$ In conlusion the taylor series for now looks like $f(z)=\\sum_{k=0}^{n-1}a_k z^k+ a_n z^n$ with $|a_n|\\leq n!\\cdot c$. What do I do with the remaining summands? Edit: I would say that for $k&lt;n$ we have $|z|^k&gt;|z|^n$ for $z\\in D_1(0)$. So since the estimate has to hold for all $z\\in \\mathbb C$ we can't have that either.", "Here's an example question from the : On the last day of a one-week sale, customers numbered 149 through 201 were waited on. How many customers were waited on that day? Possible answers: 51, 52, 53, 152, 153. The correct answer here is 53, which is the result of (201-149) + 1 = 53. What's the reasoning in adding the +1?", "Is there a quick way to set an HTML text input (&lt;input type=text /&gt;) to only allow numeric keystrokes (plus '.')?", "I am from Nigeria and I'm doing a one year Internship program with The Marriott hotel in Wisconsin, I applied for the UK visitor visa two weeks ago to visit my fiance who lives and work in the UK, but I was refused the visa because the letter of my workplace that I provided was back dated of 2014 which they say they are not satisfy it accurately reflects my current employment circumstance. I also provided my pay slips, but they said they were not satisfied with it demonstrating the terms and conditions of my employment, and they also said I did not present any evidence to satisfy me having sufficiently strong ties and commitments in my country of habitual residence or elsewhere to motivate my timely departure from the UK. They said the documents my fiance presented were OK. How soon can I re-apply for a UK visa after getting a refusal?", "Use #ifdefs and #define to optionally turn a function call into a comment Is it possible to do something like this #ifdef SOMETHING #define foo // #else #define foo MyFunction #endif The idea is that if SOMETHING is defined, then calls to foo(...) become comments (or something that doesn't get evaluated or compiled), otherwise it becomes a call to MyFunction. I've seen __noop used, but I don't believe I can use that. EDIT(s): I don't think I can really use a macro here, because MyFunction takes a variable number of arguments. Also, I'd like to make it so the arguments are NOT evaluated! (So doing something like commenting out the body of MyFunction doesn't really give me what I need, as the arguments will still be evaluated)", "Differentiability implies continuity - A question about the proof I have a question, to aid my understanding, about the proof that differentiability implies continutity.$\\mathstrut$ Differentiability Definition When we say a function is differentiable at $x_0$, we mean that the limit: $$‎f^{\\prime} ‎(x) = \\lim_{x\\to x_0} \\frac{f(x) - f(x_0)}{x-x_0}$$ exists. Continuity Definition When we say a function is continuous at $x_0$, we mean that: $$\\lim_{x\\to x_0} f(x) - f(x_0) = 0$$ Theorem: Differentiability implies Continuity: If $f$ is a differentiable function at $x_0$, then it is continuous at $x_0$. Proof: Let us suppose that $f$ is differentiable at $x_0$. Then $$ \\lim_{x\\to x_0} \\frac{f(x) - f(x_0)}{x-x_0} = ‎f^{\\prime} ‎(x) $$ and hence $$ \\lim_{x\\to x_0} f(x) - f(x_0) = \\lim_{x\\to x_0} \\left[ \\frac{f(x) - f(x_0)}{x-x_0} \\right] \\cdot \\lim_{x\\to x_0} (x-x_0) = 0$$ We have therefore shown that, using the definition of continuous, if the function is differentiable at $x_0$, it must also be continuous. My Question The proof seems to execute the following steps: Assume the function is continuous at $x_0$ Show that, with little algebra, we can change this into an equivalent question about differentiability at $x_0$. With this little bit of algebra, we can show that if a function is differentiable at $x_0$ it is also continuous. What I am slightly unsure about is the apparent circularity. In my mind it seems to say, if a function is continuous, we can show that if it is also differentiable, then it is continuous. Rather than what I was expecting, namely, if a function is differentiable, we can show it must be continuous. Hopefully my confusion is clear. Any help will be greatly appreciated.", "When I open the terminal on my Mac, this is what it shows: australia:~ rod$ I don't live in Australia, don't have anything to do with Australia, nor have ever setup terminal as Australia. Where does that name come from, why is it there, what does it mean and how do I change it (or should I even change it at all)?" ]

[ "Speed of object towards a point not in the object's trajectory?", "How do I create a dynamic key to be added to a JavaScript object variable", "Normal subgroups of $S_4$ Can anyone tell me how to find all normal subgroups of the symmetric group $S_4$? In particular are $H=\\{e,(1 2)(3 4)\\}$ and $K=\\{e,(1 2)(3 4), (1 3)(2 4),(1 4)(2 3)\\}$ normal subgroups?", "Programs never open in foreground How can I make programs open in the foreground? Nautilus will open in the background, Remmina (the remote desktop program) also opens in the background. I have to click on the icon in the Launcher for it to come to the foreground. I would think any program that is invoked by any means would come to front, as it opens. It seems if one program invokes another, it will be in the background. If I click on any icons in the Launcher though, it will actually open in the foreground.", "How do you configure proxy settings in the Ubuntu Server or Minimal (CLI) versions using the terminal?", "\"named\" vs \"that is named\" I want to describe my business and want to refer to it in a sentence. I am trying to say: \"In 2015 we established a business (that is) named X\". Intuitively, the \"that is\" part is redundant, and makes the sentence more cumbersome. But I cannot think of a reason why we should be able to drop the verb. Is the version without the \"that is\" part grammatically correct? How can it be explained?", "How to blacklist kernel modules?", "It is common for public Wi-Fi access points to include login pages, even at times, when they’re free (i.e. Starbucks, many airports, hotels, etc). I’m often in a situation where I’ll open up Chrome/Firefox, with and all my previously open tabs will start to reload. If there is a wireless login redirection page, however, every tab is redirected and reloaded and the previous page is lost from history (and the back button won't return to it). Is there any way to avoid or circumvent this behavior?", "I am wanting to find a latitude and longitude point given a bearing, a distance, and a starting latitude and longitude. This appears to be the opposite of this question (). I have already looked into the haversine formula and think it's approximation of the world is probably close enough. I am assuming that I need to solve the haversine formula for my unknown lat/long, is this correct? Are there any good websites that talk about this sort of thing? It seems like it would be common, but my googling has only turned up questions similar to the one above. What I am really looking for is just a formula for this. I'd like to give it a starting lat/lng, a bearing, and a distance (miles or kilometers) and I would like to get out of it a lat/lng pair that represent where one would have ended up had they traveled along that route.", "How do I connect to a MSSQL database using Perl's DBI module in Windows?", "Which singular names ending in “s” form possessives with only a bare apostrophe? Many questions already ask about this topic ( , , etc.) and their answers vary, but they always give exceptions to the apostrophe-s rule, for example: 6.24 The general rule for the possessive of nouns covers most proper nouns, including most names ending in sibilants.\" Examples they give include Kansas’s, Ross’s land, and Jones’s reputation. Exceptions include Jesus’  and Moses’. Which names does this apply to? Is the Aeneas’  form correct, or is it Aeneas’s instead?", "How do I fix Google Chrome's latest new tab page? I've just updated to the latest Google Chrome Dev build, and they've changed from the annoying-but-ok new tab page to an ugly and less usable page. On the old one, nine thumbnails was not enough, and now they've restricted it to eight. There's an empty \"Tips and Suggestions\" box which I wouldn't want even if it had stuff in; they've added Recent Downloads - on the rare occasions when I need that, I'll hit Ctrl-J to open the Downloads tab; and the site-specific search box on the right has now gone! Is there a way to get the old new tab page back, or a plugin to provide a superior one? Update: I launch Chrome by pressing Win+R and entering \"chrome\" - I have a shortcut on the Path with a Target of \"C:\\Documents and Settings\\&lt;user&gt;\\Local Settings\\Application Data\\Google\\Chrome\\Application\\chrome.exe\" --old-new-tab-page and whilst double-clicking this shortcut brings up the previous new tab page, using the keyboard method results in the old one. How do I get it working via the Run box? (Without using a batch file, which slows things down too much.) Update 2: GRRR! Now they've gone and stopped the --old-new-tab-page parameter from working at all! I hate this new version of the page that they're forcing upon us - can anyone provide a method to get rid of it and get the decent page back?", "Is reusing old code for a new assignment considered self plagiarism? How to protect yourself if you consider it to be, and a group partner does not? I am taking a graduate machine learning course and am working with another student in the class on a final project. In his undergraduate studies, the other student wrote code that accomplished a similar task, and mentioned in our previous meeting that we would be able to leverage much of this code for our current project if we wanted to. I responded that I believe it would constitute textbook cheating and self-plagiarism, but the other student disagrees and believes that re-using the code would not constitute self-plagiarism because he himself wrote it, and it would be redundant to re-write what he had already done. Now, the course instructors have made it clear that we are not allowed to use any external libraries to perform certain classes of algorithms for this project. This students' prior code would fall under this category of prohibited tools, but he claims that it doesn't qualify because he wrote the code himself (so it is not an \"external library\"). I believe this is hyperbole, but he disagrees. It is also worth mentioning that this code is licensed under an , though it is not widely used at all. It has gotten to the point where I am uncomfortable going forward with the project by re-using his old code, and he does not want to do work on the project that he considers to be redundant. My worry is that if it turns out we're not allowed to reuse the code, then using it could cause us to fail the course and severely negatively affect our reputations. Even if we don't get caught, I personally feel that it would be unethical to copy-paste old code and present it as though it's fresh code for this current project. I am unsure of how to proceed. I have tried reaching out to the professor of the course some time ago (she has been traveling for some conferences recently and will be for a while) but I have not heard back from her. Additionally, the course TAs have been unwilling to weigh-in on the situation. I have the following questions: Is the above situation usually considered to be self plagiarism? Why or why not? Is the above act typically allowed in an academic setting? Assuming you are in my position, and consider re-using the code to be cheating and/or unethical, what is the best way to proceed; both in terms of how to make progress on the project, how to compromise with my group mate, and how to protect myself if my group mate refuses to budge.", "If a sports team is down by 1-2 in a best of 7 series, what is their chance of winning (if both teams have a 1/2 chance of winning every game)? I know that the team has to win 3 of the 4 remaining games. So I thought that from the 4 remaining games, there are a total of $2^4 = 16$ total different outcomes. Could someone point me towards the right direction to determine the probability of the team winning 3 of the 4 remaining games? Would it be 4C3/16 since the three wins can be chosen amongst the 4 games left?", "Need help identifying short story about retired military colonel who fought war at end of time I read this story in an anthology in the eighties or early nineties. It was about an old man who lived outside a western-like town, though that might have just been how I imagined it. He goes to town and some ex-military thugs are there causing problems. Flaunting some odd interdimensional military tech of some sort. He doesn't want to intervene as doing so would be bad but in the end he must. By intervening, his military identity is revealed and that causes him (some paradox or causality law) to have to go back and fight the war again. The war is at the end of time or the universe. The man is maybe a colonel of the sky something... Not much to go on; I have been searching my collection and wracking my brain for years trying to recall the story.", "\"can't\" versus \"couldn't\", what is the difference? That can't be Obama at the door, it's too early. That couldn't be Obama at the door, it's too early. What is the difference between them? Are they almost the same?", "I have an accompanied visa with my grandparents but because of some reason they cannot travel with me. I am above 17 years. Can I travel alone and will I be allowed to enter UK as my real aunt puts up there?", "Cannot reach public WIFI login page in Ubuntu 18.04 Captive Portal Issue", "17.10 Super key to open applications", "The parmesan cheese in pasta recipe is quite expensive.....do we have cheaper alternative?? Are there are cheddar cheese which can replace parmesan cheese?" ]

[ "Sorry to start a subjective question, but want to understand \"own.sty\" file. Other than all \\usepackage{} what sort of other commands can be added to the makeyourown.sty file. Can you include \\let command, and \\newcommands in it. What sort of precaution / structure newbies should follow.", "Stitch first and edit later or vice versa? I have a set of three images imported in Lightroom 3.6 which I want to stitch into one panorama using Photoshop's CS5.5 Merge to Panorama tool. As I see it I have two options in doing so. Doing all modifications (colour, brightness, contrast, etc...) first, syncing the changes between the three photos and then stitch them together. Stitching the photos first and then use Lightroom to apply modification to the whole image. Which of these two methods is considered to be best practice?", "Indent math blocks? I want all math blocks \\begin{math} in my document to be intended automatically, like it's the case with \\begin{itemize}. Can anyone please give me a hint on how to do this? Thanks :-)", "Is there a difference between “?!” and “!?”?", "Okay, so I think I have a decent enough sample, taking into account the 20:1 rule of thumb: a fairly large sample (N=374) for a total of 7 candidate predictor variables. My problem is the following: whatever set of predictor variables I use, the classifications never get better than a specificity of 100% and a sensitivity of 0%. However unsatisfactory, this could actually be the best possible result, given the set of candidate predictor variables (from which I can't deviate). But, I couldn't help but think I could do better, so I noticed that the categories of the dependent variable were quite unevenly balanced, almost 4:1. Could a more balanced subsample improve classifications?", "This question is from a set of optional, much harder problems from my first year analysis course, but the subject material is norms on $\\mathbb R^K$. (c) Show that there exists a constant $C &gt; 0$ such that for all $\\mathbf x ∈ \\mathbb R^k$, $||\\mathbf x||\\le C||\\mathbf x||_\\infty$ Hint: Use the standard unit vectors to write $\\mathbf x = x_1\\mathbf e_1 +. . .+x_n \\mathbf e_n$, and use the triangle inequality. (d) Show that there also exists a constant $c &gt; 0$ such that for all $x ∈ \\mathbb R^k$, $||\\mathbf x||_\\infty \\le c||\\mathbf x||$ Hint: If it isn’t true, then you can find a sequence $⟨\\mathbf x_n⟩$ such that $||\\mathbf x_n||$ is bounded but $c_n := ||x_n||_∞ → ∞$. (Why?) Think about the sequence $⟨\\mathbf x_n/c_n⟩$. The Bolzano-Weierstrass theorem may be of assistance. Note that the unspecified norm represents any norm for $\\mathbb R^k$. I've done part c), but am stuck on part d). I've had a look for proofs on other questions on MSE, but none of them seem relevant to the hint given, and frequently the terminology is too advanced for me. I tried considering the case if it isn't true, as suggested, but I can't see how to bound any sequence using that. Any help would be much appreciated.", "When should I fudge dice rolls? When I started my first D&amp;D campaign as a DM, I accidentally rolled and confirmed a crit on a PC from a goblin. It was an instant kill as our campaign had no cleric. That time I decided to fudge the dice. Now, there's a similar problem, but this time the PCs are at 3rd level and they are dealing with a very important NPC. If they fail this one diplomacy check, the entire game world will fall apart, as the king would then send his entire army against the PC's homeland and will destroy it, plunging my entire game world into chaos, at which time drow that I wanted to save for a later adventure will have to come out, which will instigate a wizard's guild to release their secret ultra-deadly virus, and everything in my game world, including the PCs, will die. So should I fudge the dice roll? When is it good to fudge it?", "Creating or adding geometry colunm fails even with postgis enabled", "Checking the maximality of a principal ideal in $R[x]$ Let $R = \\mathbb{Z}_{(2)}$ be the localization of $\\mathbb{Z}$ at the prime ideal generated by $2$ in $\\mathbb{Z}$. Then prove that the ideal generated by $(2x-1)$ is maximal in $R[x]$.", "Do electrons in an electron beam (cathode ray) follow the ? Or in other words, does the Pauli exclusion principle apply for the beam of electrons?", "Additive Roman Numeral 4 I am working on a diplomatic edition of a 15th century book and it numbers its folios using the standard roman numerals of the time. I've been using the following to get the page/folio in my header: \\newcommand{\\rectoverso}[1]{\\ifthenelse{\\isodd{#1}}{r}{v}} \\newcommand{\\folio}[1]{\\the\\numexpr (#1+1)/2\\relax} \\uppercase\\expandafter{\\romannumeral \\value{\\folio{\\thepage}}}\\rectoverso{\\thepage} This works great, but the problem is that the roman numeral sequence is off of what I need. Instead of I, II, III, IIII, V, VI, VII, VIII, IX, X, I get the subtractive IV (somewhat understandably, given it's the far more common one in modern usage). My source text only (and always) uses the additive 4 in the one's position: 24 is XXIIII, 34 is XXXIIII but 44 is XLIIII. 9 is universally rendered subtractively as IX or XC. Is there a package that allows for some control over which numbers are done additively and which are subtractively, or would my best option be to write my own custom definition to account for the specific style used in my book?", "Switch statement fall-through...should it be allowed?", "What is the meaning of \"would\", and how to use it? What is the meaning of would, and which tense is it used in the following sentences? For example, That would be Ram calling. I'll answer it. (the meaning of would and which tense is used) The guy on the phone had southern accent. That would be Tom. (the meaning of would and which tense is used) “We saw a police helicopter overhead yesterday morning.” “Really? They would have been looking for those bank robbers.” (the meaning of would and which tense is used) You would have to say/do that. (Why is would used here? What happens to the meaning if would is removed?) John said he didn't steal any money. Well, he would, wouldn't he ? (Why is would used here?) Why is would used in sentences 1, 2, and 3 to mean \"presumption\" instead of using other modals, such as: must and should? Does the meaning change if used others? Can we use will, must, should and could in the place of would, without changing the meaning of sentences? What kind of meanings would it make if they (will, must, should, and could) are used in the place of would? I'd be grateful if you could answer me.", "In Captain America: Civil War, T'Challa takes the mantle of the Black Panther after his father is killed. As the Black Panther, he appears to have enhanced abilities. In , the Russos talk about T'Challa having superpowers and being enhanced during Civil War JOE: It can absorb the energy, so it’s much harder to damage him as a character, and you can see that in the movie he can take a lot of punishment including bullets to the face. He is very well trained. He’s from one of the wealthiest countries on the planet, so there’s great infrastructure there; very technologically advanced country. So he’s been trained at the highest levels to fight, but he also has his own superpowers, which derive from the mythology of his nation. Those will be explored more in Black Panther, it’s clearly evident when he’s able to fight the Winter Soldier out of costume, and go toe-to-toe with him, that he is an enhanced individual. In Black Panther, we see that in order to become the Black Panther, one must imbibe juice from the heart-shaped flower and visit the spirit plane after being buried. But before this, T'Challa must have his Black Panther powers removed prior to the ritual combat challenge, which he does twice in the film. This raises the question of how T'Challa could have possibly become the Black Panther abroad - or if he even really had. How did Black Panther have his powers during Civil War?", "The recent discovery by the LIGO made me wonder about this. We know that there exists a CMBR, Cosmic Microwave Background Radiation, a blanket of electromagnetic energy covering the universe, made by the Big Bang. But, the big bang was an explosive event. The huge \"shockwave\" made by it sent ripples in space time. (Primordial gravitational waves) Wouldn't these ripples flood the universe creating sort of a Cosmic Gravitational Background Radiation (not exactly radiation)? If such waves do flood the universe, couldn't a much more sensetive version of LIGO be able to detect this and use it as a contrast to create \"gravitational telescopes\"?", "biblatex broken overnight As late as last week my setup for biblatex worked fine. Going back to the same project today not even a minimal file compiles: \\documentclass{article} \\usepackage{biblatex} %\\addbibresource{biblatex-examples.bib} \\begin{document} test%foo\\nocite{*} %\\printbibliography \\end{document} but breaks off with /usr/local/texlive/2017/texmf-dist/tex/latex/biblatex/biblatex.sty:3776: LaTeX Error: Missing \\begin{document}. See the LaTeX manual or LaTeX Companion for explanation. Type H &lt;return&gt; for immediate help. ... l.3776 australian,newzealand} ? /usr/local/texlive/2017/texmf-dist/tex/latex/biblatex/biblatex.sty:3776: Math f ormula deleted: Insufficient symbol fonts. \\expandafter -&gt;american| l.3776 australian,newzealand} And keeps repeating the last one until (That makes 100 errors; please try again.) when I ignore it. Files without biblatex work as expected. Using tlmgr to go my two backup versions of biblatex back in time to 1st Jan I still get the same errors. Could this be another update from the last week or so that causes this? If I swich back to TL 16 things work as expected. (For my work I need TL 17 because of packages.)", "How do I theme a webform?", "Sometimes after I fry something, I wash it immediately in water because it's a bit easier to wash (before the remains stick to the pan). Does this damage the pan in any way?", "Conky does not work properly on Ubuntu 16.04 GNOME I have this strange problem with conky. It doesn't show properly on the desktop: I've tried everything from editing conky widget file to reinstalling conky and conky manager (v.2.4). Who knows how to fix it?", "When do I need to invoke \\phantomsection?" ]

[ "When is logistic regression solved in closed form?", "Prove that the sequence with $T(0)=1$ and $T(n) = 1 + \\sum_{j=0}^{n-1}T(j)$ is given by $T(n)=2^n$ $T(0)=1 \\\\ T(n) = 1 + \\sum_{j=0}^{n-1}T(j) \\\\ $ Show that $T(n) = 2^n$. I know how to prove this by induction, but I would like to know how to show this using first principles. Edit: The way I want to solve this problem is manipulate $T(n)$ in such a way that it ends up as $2^n$.", "A function that is continuous at the origin but not differentiable there Show that $f(x,y)=\\dfrac{xy^2}{x^2+y^2}$ (with $(x,y)\\not=(0,0)$ and $f(0,0)=0$) is continuous but not differentiable at $(0,0)$. I tried to show continuity with an $\\epsilon -\\delta$ argument but I don't know how to factorize the expression so that I can have something useful. For differentiability I think I should show that the partials are not continuous at $(0,0)$. But finding the partials is also painful.", "\"He was neither seer nor prophet\" How would you explain the absence of an article? Here's a fragment from Jack London's Star Rover: Wordsworth knew. He was neither seer nor prophet, but just ordinary man like you or any man. What he knew you know, any man knows. But he most aptly stated it in his passage that begins \"Not in utter nakedness, not in entire forgetfulness. To the best of my — admittedly sketchy — knowledge of grammar, the second sentence should read neither a seer nor (a) prophet, but just an ordinary man. Even if we accept the seer and the prophet as \"poetic entities\" (\"father and son,\" \"robber and robbed,\" \"man to man,\" or whatever), logic would still dictate that ordinary man should be preceded by an an. It is a well-known fact that Jack London's usage wasn't always up to par; his grammar, on the other hand, was always top-notch. Logically, the sentence is grammatically incorrect (correct me if I'm wrong: no pun intended). Illogically, it reads smoothly: intuitively, a native speaker understands that there's nothing wrong here. However, those to whom English is not the first language cannot be expected to be intuitive in this case and would want an explanation. Any suggestions?", "To what extent is WhatsApp's statement on secure messaging realistic?", "Beamer: \\nonumber equivalent for slides? Is there an equivalent command to \\nonumber when one doesn't want to include certain slides in the numbering? I would like to leave outline and title slides out of my numbering, and instead just number slides with actual content. Other workarounds would be nice to know about as well. Edit: Since a MWE example was requested, here is one. Suppose I have a title page and two other slides. The code below gives a slide counter that goes up to 3, and the title slide is slide 1. I would prefer to have the title slide not be numbered, the counter go up to 2, and the the numbering start at the slide after the title. Here is some code. \\documentclass{beamer} \\mode&lt;presentation&gt; { \\usetheme{Dresden} } \\setbeamertemplate {footline}{\\quad\\hfill\\insertframenumber/\\inserttotalframenumber\\strut\\quad} \\begin{document} \\begin{frame} \\titlepage \\end{frame} \\begin{frame} Some actual content here \\end{frame} \\begin{frame} Some more actual content here \\end{frame} \\end{document}", "How to apply multiple format to a list", "Why are conference papers so important in computer science (CS)? From my understanding many CS conferences are highly selective and the papers are peer-reviewed. The CS field also seems to publish traditional journal articles. I do not understand the difference between the two and in particular I am curious about the advantages of having two different publication streams. The type of things I am curious about are: What is the difference between a paper published in a top CS conference and a top specialist journal? Is one more prestigious than another and if so how do they line up? Why not just publish conference papers as a special issues of a journal?", "Integrating a function of tan inverse How would I carry out the following integration? $$\\int_0^12\\arctan x^2$$ I tried to substitute $x^2 = \\tan\\theta$ From there I wrote the integral as: $$\\int_0^{\\pi/4}\\theta\\cdot \\frac{\\sec^2\\theta}{\\sqrt{\\tan\\theta}}\\ d\\theta$$ Now, is my only option to use integration by parts? Or is there a better method to solve this integral?", "Filter questions with no accepted answer I have some questions with answers, but none of the answers are acceptable (just wrong). I'm sure there are a lot more people with the same problem. Can you add a button to filter questions with answers but no accepted answer? This way, people will see those questions and maybe try to offer a new perspective.", "How to make a persistent live Ubuntu USB with more than 4GB I want to make a persistent live Ubuntu USB drive with more than 4GB of storage. I know there is an option of installing directly on the drive but I don't want to do this as it will restrict the drive from working on different computers. One option is to make an additional partition with extra space but if I do this how can I get newly installed software to be stored on this partition?", "Moving from SQL 2005 [SQL_Latin1_General_CP1_CI_AS] to 2008 - will I lose any features by using 'backwards compatibility'", "\"Timed Out\" error when trying to join server", "What would be a good way to go about attacking a Quagmire 3 cipher? I understand that it is polyalphabetic with a key and an indicator. I have started by taking the cipher text, taking every n-th letter and putting that in a string, computing the index of coincidence for the n strings I get and then averaging that. I would assume that whatever n value corresponds with the closest average index of coincident to English (0.066) would be the number of alphabets, i.e. the length of the indicator. Where do I go from there? Or is my approach incorrect?", "How to style text in hyperref \\url? I want to set color, font and similar style attributes for the text in a \\url from the hyperref package. How do I go about doing it? All I have found are . I want to because I am using ttf fonts for my texts and I want my urls to be in that ttf and not the default (typewriter font?) that the hyperref package gives me. I started with just trying to get it in italics but didn't even succeed with that: \\documentclass{memoir} \\usepackage{hyperref} \\begin{document} Lala \\url{\\itshape www.example.com}. \\end{document} I am guessing there is some hook or something but I just can't find it. Maybe I have gone blind?", "Macro for figure position? Why is the following minimal example not working? I.e., what do I need to do, in order to define the float placement specifier of a figure within a macro? (I know that I should use \\newcommand, but in the \"full\" example the error is part of an involved \"superfigure\" command. \\newcommand is not working too btw.) \\documentclass{scrreprt} \\usepackage{blindtext} \\def\\PosNotWorking{h} \\def\\FramboxNotWorking{5cm} \\def\\CaptionWorking{Caption is working.} \\begin{document} \\Blindtext[1] \\begin{figure}[\\PosNotWorking] \\centering \\framebox[5cm]{My special figure. (Pos: \\PosNotWorking)} \\caption{\\CaptionWorking} \\end{figure} \\Blindtext[1] \\end{document} If I compile this, the figure is at the top (default behaviour). If I enter \\figure[h] instead of \\figure[\\PosNotWorking], the figure is of course between the two paragraphs.", "Can a ultracentrifuge be used to test general relativity? With today's ultracentrifuge technology, they can spin so fast that the sample can be subjected to accelerations of up to 2 millions Gs. That is equivalent to two solar masses. Has someone tried to measure the time dilation in a radioactive sample? How calculate that time dilation respect to the time outside the ultracentrifuge, for example one week. I think that that time dilation will be significant enough to be measured.", "Evolving Pokemon based on CP vs Moves Many people are evolving their pokemons based on the CP. However, there's a growing number of people evolving based on Moves instead of CP. In other words, choosing pokemons that have the highest Moves to keep, even if it isn't necessarily the highest CP. I am new to pokemon and don't quite understand the difference between the two. Thus, which strategy is better?", "show that Cov(X+ Y, X-Y)= Var(X) - Var(Y)", "Can I completely disable Cortana on Windows 10?" ]

[ "Accessing laptop's hard drive when OS won't boot", "How do you make Ubuntu accept files sent over bluetooth", "Is there a detailed user's documentation for KDE Plasma 5?", "nginx location match issue auth_basic I have this configuration : location / { root /etc/nginx/euchet; } location /app/ { proxy_pass http://172.16.184.2:8080; proxy_redirect off; proxy_set_header Host $host; proxy_set_header X-Real-IP $remote_addr; proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for; proxy_set_header REMOTE_ADDR $remote_addr; } And I need to add another location with auth_basic enabled only for the request: /app/f?p=3000 I tried with rexexp: location ~ \\/appt\\/f\\?p=3000 { auth_basic \"Hello! Enter password\"; auth_basic_user_file /etc/nginx/euchet.htpasswd; proxy_pass http://172.16.184.2:8080; proxy_redirect off; proxy_set_header Host $host; proxy_set_header X-Real-IP $remote_addr; proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for; proxy_set_header REMOTE_ADDR $remote_addr; } Nginx use previous location /app/. I tried another way: location ~* /euchet/f { if ($arg_p = \"4550\") { return 403; } error_page 403 = @hidden; } location @hidden { auth_basic \"Hello! Enter password\"; auth_basic_user_file /etc/nginx/euchet.htpasswd; proxy_pass http://172.16.184.2:8080; proxy_redirect off; proxy_set_header Host $host; proxy_set_header X-Real-IP $remote_addr; proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for; proxy_set_header REMOTE_ADDR $remote_addr; } And I get 403 error on f?p=3000, and 404 errors on f?p=&lt;another_number&gt; How can I fix this problem?", "Why can't cloaked vessels shoot?", "Lag compensation with networked 2D games I want to make a 2D game that is basically a physics driven sandbox / activity game. There is something I really do not understand though. From research, it seems like updates from the server should only be about every 100ms. I can see how this works for a player since they can just concurrently simulate physics and do lag compensation through interpolation. What I do not understand is how this works for updates from other players. If clients only get notified of player positions every 100ms, I do not see how that works because a lot can happen in 100ms. The player could have changed direction twice or so in that time. I was wondering if anyone would have some insight on this issue. Basically how does this work for shooting and stuff like that? Thanks", "Does a run scored on a tag out on a forced runner? The situation: Runners at third and first, ball is hit to the second basemen, 2nd basemen goes to tag the runner out. Runner stops, runner on third scores and then 2nd basement tags the runner, does not step on base.Does the run count?", "Test if there are files matching a pattern in order to execute a script I am trying to write an if statement to test whether there are any files matching a certain pattern. If there is a text file in a directory it should run a given script. My code currently: if [ -f /*.txt ]; then ./script fi Please give some ideas; I only want to run the script if there is a .txt in the directory.", "Can you have a class in a struct?", "Why is the minimum size of a generating set for a finite group at most $\\log_2 n$? It seems to be known that the minimum size of a generating set for a finite group of order $n$ is at most $\\log_2 n$. Can someone explain why this is true? Edit: noted that the logarithm is base 2, and $n$ represents the order of the group.", "How to align a to the middle (horizontally/width) of the page", "Polar form to cartesian Let $\\Gamma$ be a circle that passes through the origin. Show that we can find real numbers $s$ and $t$ such that $\\Gamma$ is the graph of $r = 2s \\cos (\\theta + t).$ I know this has to be converted to a cartesian equation, but how do I do this, and what do I do after? Thanks", "Can a word be contracted twice (e.g. \"I'ven't\")?", "How are Wolverine's claws still in his body? Everyone knows that Wolverine's adamantium claws are super-sharp — sharper than even a razor — and virtually indestructible. What puzzled me the first time I saw Wolverine is: how do the claws stay in his body? As it is shown, Wolverine's flesh and skin are human in strength, but the healing factor makes it superhumanly durable and strong. Still, when Wolverine slashes something, or someone, extremely hard, dense, or thick (as he has to use great amount of force), the claws don't tear through his hand and leave his hand through the opposite side of the palm (because of the action having equal and opposite reaction).", "Why is quantum entanglement considered to be an active link between particles?", "I have an alias that I would like to use both as a regular user and as root, via sudo. Specifically, it is this: alias rm=trash This works fine as a normal user, and it works fine when I use sudo -i to get a root shell prompt, but if I use sudo rm, the alias does not apply. So where do I need to put my alias so that it works in one-off sudo commands?", "How to set up a root cron job properly I tried to set up a root cron job to run a Bash script as root, to run at minute 7,37, every hour, every day of month, every month. This script is located in /usr/bin and named tunlrupdate.sh. It updates the DNS of Tunlr. $ ls -l /usr/bin/tunlrupdate.sh -rwxr-xr-x 1 root root 2133 Sep 24 15:42 /usr/bin/tunlrupdate.sh This Bash script is available . When invoked the script writes what's happening in a log located in /var/log/tunlr.log To add this root cron job I used the standard for root's crontab sudo crontab -e And inserted these 2 lines at the end. I expect cron to run the script as root. # check for updated Tunlr DNS every 30 minutes at the hour + 7 mn and hour + 37 mn 07,37 * * * * root /usr/bin/tunlrupdate.sh A later command sudo crontab -l confirmed that the cron job has been inserted. I did reboot Ubuntu and was checking in the log file if the cron job was launched properly. However there is nothing in the logfile /var/log/tunlr.log meaning the job was never successfully launched. I did check that if I run the script from the command line sudo /usr/bin/tunlrupdate.sh then the logfile is updated accordingly. Why is this cron job not running as planned in my system? UPDATE 1 : All the proposed solutions so far do not work. I thank Olli for a CLI to list the system log sudo grep CRON /var/log/syslog. However I did get a CRON error CRON[13092]: (root) CMD ( [ -x /usr/lib/php5/maxlifetime ] &amp;&amp; [ -d /var/lib/php5 ] &amp;&amp; find /var/lib/php5/ -depth -mindepth 1 -maxdepth 1 -type f -cmin +$(/usr/lib/php /maxlifetime) ! -execdir fuser -s {} 2&gt;/dev/null \\; -delete) with the suggested PATH= insertion &amp; use of absolute path from root for functions in the script or without this suggested solutions here. I still get this error. After some searching I pinpointed the error in the file /usr/lib/php5/maxlifetime as is explained : Change #!/bin/sh -e --&gt; #!/bin/sh -x Then listing the CRON error log in my system sudo grep CRON /var/log/syslog Feb 11 18:07:01 Marius-PC CRON[14067]: (root) CMD (root /usr/bin/tunlrupdate.sh) Feb 11 18:07:01 Marius-PC CRON[14066]: (root) MAIL (mailed 1 byte of output; but got status 0x00ff, #012) I still don't get the bash script executing. This time no error is shown in the log. To get assurance this was not the content of the script I reduced the script to the following 3 lines: #!/bin/bash LOGFILE=/var/log/tunlr.log echo $LOGFILE &gt;&gt; $LOGFILE I still don't get the cron job through. Nothing is written in the log file. So even may be an empty script will not run in cron ? I don't get it. I am know trying a script reduced to these 2 lines: #!/bin/bash exit 0 And still the same error log. The cron script does not go through ...", "Why doesn't Normal[] work on GeometricTransformation?", "Closure of the set of degree $n$ polynomials with $n$ real roots A very beautiful (but maybe classic) exercise: Consider the set $\\Omega_n$ of polynomials of degree $n$ with real coefficients and $n$ distinct real roots. What is the closure of $\\Omega_n$ in $R_n[x]$? ($R_n[x]$ denotes the set of polynomials with real coefficients of degree at most $n$) The answer is the set of polynomials in $R_n[x]$ all of whose roots are real, plus the constant polynomials. Showing that this set is contained in the closure is not too hard, however the reverse implication is more difficult and I'm wondering what is the most elementary method to prove it (without talking about holomorphic functions for example).", "Every time I try to install \"WINE\" VIA the Software Center on Ubuntu 12.10, I get this error: The following packages have unmet dependencies: wine1.4: PreDepends: dpkg (&gt;= 1.15.7.2~) but 1.16.7ubuntu6 is to be installed Depends: libc6 (&gt;= 2.14) but 2.15-0ubuntu20 is to be installed Depends: wine1.4-amd64 (= 1.4.1-0ubuntu1) but 1.4.1-0ubuntu1 is to be installed Depends: wine1.4-i386 (= 1.4.1-0ubuntu1) but it is not going to be installed When I try installing it VIA the terminal, this is what I get: Reading package lists... Done Building dependency tree Reading state information... Done Some packages could not be installed. This may mean that you have requested an impossible situation or if you are using the unstable distribution that some required packages have not yet been created or been moved out of Incoming. The following information may help to resolve the situation: The following packages have unmet dependencies: wine1.4 : Depends: wine1.4-i386 (= 1.4.1-0ubuntu1) but it is not installable Recommends: gnome-exe-thumbnailer but it is not going to be installed or kde-runtime but it is not going to be installed Recommends: ttf-droid Recommends: ttf-mscorefonts-installer but it is not going to be installed Recommends: ttf-umefont but it is not going to be installed Recommends: ttf-unfonts-core but it is not going to be installed Recommends: winbind but it is not going to be installed Recommends: winetricks but it is not going to be installed E: Unable to correct problems, you have held broken packages. how do I fix this?" ]

[ "How can I create launchers on my desktop? In older versions it was easy to create a launcher on my desktop. All I had to do is right click on my desktop and select the \"create launcher\" option. How can I create such launchers now?", "Positivity of a determinant", "Why does the question's closed status disappear when clicking to load a new edit?", "Renaming hundreds of files at once for proper sorting", "Draft mode for pgfplots I'm working on a fairly big document that has a lot of graphs of functions- so far it has around 200, by the end it will have around 1500. I use pgfplots for each graphic, and the functions are pretty basic: exponential, rational, polynomial, and trigonometric. Once I am happy with each graph, I don't necessarily need to see it every time I compile, and would like to minimize compilation time for future drafts. Naturally, the document is already chopped up into chapter files, but each chapter contains around 100 figures. Having studied the pgfplots documentation, I haven't found a draft mode, but I'm interested in knowing if one could be created. I'm envisaging something similar to the draft mode of the graphicx package, in which graphics are not included, and blank boxes are put in their place. Some things I've considered: the documentclass; but with about 1500 figures, wouldn't this mean over-modulization? tikzexternalize, but this still requires an initial 'monster' compilation to get the images externalized before the draft option could be invoked Here's a MWE to play with \\documentclass{article} \\usepackage{pgfplots} \\begin{document} \\begin{tikzpicture} \\begin{axis} \\addplot {x^2}; \\end{axis} \\end{tikzpicture} \\end{document}", "Structure of a C++ Object in Memory Vs a Struct If I have a class as follows class Example_Class { private: int x; int y; public: Example_Class() { x = 8; y = 9; } ~Example_Class() { } }; And a struct as follows struct { int x; int y; } example_struct; Is the structure in memory of the example_struct simmilar to that in Example_Class for example if I do the following struct example_struct foo_struct; Example_Class foo_class = Example_Class(); memcpy(&amp;foo_struct, &amp;foo_class, sizeof(foo_struct)); will foo_struct.x = 8 and foo_struct.y = 9 (ie: the same values as the x,y values in the foo_class) ? The reason I ask is I have a C++ library (don't want to change it) that is sharing an object with C code and I want to use a struct to represent the object coming from the C++ library. I'm only interested in the attributes of the object. I know the ideal situation would be to have Example_class wrap arround a common structure between the C and C++ code but it is not going to be easy to change the C++ library in use.", "What is wrong in this proof: That $\\mathbb{R}$ has measure zero Consider $\\mathbb{Q}$ which is countable, we may enumerate $\\mathbb{Q}=\\{q_1, q_2, \\dots\\}$. For each rational number $q_k$, cover it by an open interval $I_k$ centered at $q_k$ with radius $\\epsilon/2^k$. The total length of the intervals is a geometric progression that sums up to $\\epsilon$. Each real number is arbitrarily close to a rational number since $\\mathbb{Q}$ is dense in $\\mathbb{R}$. Thus, each real number is in one of the open intervals. Thus the entire real line is covered by the union of the $I_k$, thus $\\mathbb{R}$ is a null set with measure zero. Clearly there is something wrong in the above proof, however I am not sure where is it? Thanks for any help.", "Are Newton's \"laws\" of motion laws or definitions of force and mass?", "Can you forgo your readied action to take an opportunity attack instead? Example: Player 1 uses the ready action to do something when something happens (unimportant) Goblin, decides to charge across the battlefield and attack Player 2, but happens to cross paths with Player 1 possibly provoking an opportunity attack (here lies my question) Could Player 1 decide to ignore their readied action and use their reaction to attack the goblin? This would of course take up their reaction so they could no longer take their readied action when it triggers. If so; let's say it is a fireball that was readied (or any spell), would Player 1 be required to drop the fireball spell? They technically cast it as part of their ready action, but I would understand if this would be a downside to using a reaction before their readied action triggered (maybe this should be another question, but please answer it anyway and tell me if I need to create a separate one so you can answer it there too :P).", "Breadcrumb hyperlink header", "Why is the automatic login disabled for users with encrypted home? I've tried to setup an autologin, but that isn't possible, because my home is encrypted. What are the reasons for this? PS. Here I have described my problem: .", "I have a corrupt tarball on my hands. My first attempt at recovery went like this: $ tar --ignore-failed-read --ignore-command-error -xf tarball.tar tar: Skipping to next header tar: Archive contains ‘180738 0’ where numeric mode_t value expected tar: Archive contains ‘0.445647 -9.’ where numeric time_t value expected tar: Archive contains ‘.259273 ’ where numeric uid_t value expected tar: Archive contains obsolescent base-64 headers tar: Archive contains ‘-0.94874’ where numeric gid_t value expected tar: text from a text file is here: implausibly old time stamp 1969-12-31 18:59:59 tar: more text file contents are here: Unknown file type 'p', extracted as normal file tar: Skipping to next header tar: Skipping to next header tar: Exiting with failure status due to previous errors This didn't extract much from the tarball before erroring out. The exit status is 2 which the tar man page says is a fatal error. The documentation for \"\" suggested this: cpio -F tarball.tar -i -v This extracted 1.2G of a 1.8G tarball, which is pretty good. It stops with a bunch of garbage entered after the terminal prompt -- it isn't printed to the screen, it's as if I had typed it and didn't hit return yet. Is there a way to do any better? Is there a way to try and \"jump over the bad chunks\" of the tarball? With --ignore-zeros tar seems to be reading through the entire tar file. tar -R --ignore-failed-read --ignore-command-error --ignore-zeros -xvf tarball.tar [...] block 3670356: ** Block of NULs ** block 3670357: ** Block of NULs ** block 3670358: ** Block of NULs ** block 3670359: ** End of File ** tar: Exiting with failure status due to previous errors There are a lot of Block of NULs errors so it looks like the contents might be irretrievable.", "Deactivate all \\alt,\\uncover in beamer (for printing) I have a big latex beamer that uses \\alt, \\uncover, ... to create \"animations\". My goal is to deactivate all these commands temporary (let's say : just use the last state/slide each time there's this kind of thing) to print my document. Is there a global command to do this or have I to do all this manually (comment manually the commands / or (simpler but still really long) suppress manually pages from the output) ? Thanks very much in advance for your help.", "Downloading from Play Store gives error 491 When I try to download anything from the Play Store it shows error 491 and can't finish the download. I have a Samsung Galaxy S 7582. How do I fix this?", "Can fresh pasta sheets be used to assemble a lasagne, then left in the fridge overnight before baking? Or will this make them mushy or otherwise degrade them? I have recently gotten into making fresh pasta, and I want to prep a lasagne the night before. I have done this before with store-bough dried noodles, but I'm not sure if doing this will have a negative effect on fresh, more delicate pasta.", "What happens to the human inside the titan when the titan dies? Just to be clear I'm NOT talking about those who where swallowed. We know that titans used to be humans and then somehow they transformed into titans. When they kill a titan it completely Vaporizes and nothing is left. So what happens to the human inside them? Could it be like when Eren was testing his limits and each time he fused more with the titan body? If so, why could Ymir live in titan form for over 60 years and still transform back into human?", "I have multiple datasets that I am attempting to use principal component analysis (PCA) on in order to infer the underlying structure of the data. I'm attempting to predict growth increment of conifers (the response which apparently needed to be cube root transformed for my original linear models). My predictor variables include: continuous (some log-transformed like size-related variables, some compositional, and some traditionally scaled); binary; ordinal; and nominal (of which I'm pretty sure I can order with respect to site productivity). I'm mostly attempting to make inferences because some of my previous models from linear regression have not produced significant terms corresponding to categories like health or climate and I feel that they should have. I've read in Joliffe (2002) that I might want to leave my compositional data uncentered. Forgive my naiveté, but I'm wondering if I should also do this for my binary data. It also seems that I might not want to scale these since they're already on a 0 - 1 scale but I'm not sure. After only using my continuous predictors (including compositional variables), it appears that a size principal component makes up the largest portion of the variability and Joliffe also mentions that one might want to attempt a \"double-centering\" of the log-transformed data if this is the case. I don't know if this is even possible since the log-transformed data only makes up a small portion of my datasets. Finally, I should ask if having such a combination of data types will complicate analysis so much that it will make inferences unreliable. I am currently using R for this analysis. Thank you.", "Simple examples of uncorrelated but not independent $X$ and $Y$ Any hard-working student is a counterexample to \"all students are lazy\". What are some simple counterexamples to \"if random variables $X$ and $Y$ are uncorrelated then they are independent\"?", "In Ubuntu releases prior to Ubuntu 19.10 Eoan Ermine, when I run a command with sudo, that command receives my home directory in the $HOME environment variable. This is the behavior I have long expected and . If I want sudo to reset the $HOME environment variable, so that it refers to the target user's home directory instead of my own, I have to pass the -H option (or -i, though that does more). ek@Kip:~$ lsb_release -d Description: Ubuntu 18.04.3 LTS ek@Kip:~$ sudo printenv HOME # Shows ek's home, not root's. /home/ek ek@Kip:~$ sudo -u as printenv HOME # Shows ek's home, not as's. /home/ek ek@Kip:~$ sudo -H printenv HOME # Shows root's home. /root ek@Kip:~$ sudo -Hu as printenv HOME # Shows as's home. /home/as When I first upgraded to Ubuntu 19.10, I was surprised to discover that sudo seems to reset $HOME no matter what! I continue to observe this now that 19.10 is released and I've installed updates--both on newly installed systems and one I upgraded to 19.10. ek@Cord:~$ lsb_release -d Description: Ubuntu 19.10 ek@Cord:~$ sudo printenv HOME # Shows root's home, even without -H or -i. /root ek@Cord:~$ sudo -u as printenv HOME # Shows as's home, even without -H or -i. /home/as ek@Cord:~$ sudo -H printenv HOME # Also shows root's home. /root ek@Cord:~$ sudo -Hu as printenv HOME # Also shows as's home. /home/as I thought this might be due to . But I checked, and always_set_home does not appear in any Defaults line in my 19.10 /etc/sudoers file. What makes sudo treat $HOME differently starting in 19.10, and why was this change made? Does this make it safe to use plain sudo in cases where I would previously have used sudo -H?", "The screen of my phone is physically broken, so it doesn't display anything, but the touch aspect does seem to be working, as I can unlock my phone, and get haptic feedback. Before I go to get it replaced, I'd like to back up some personal data from the built-in memory to the SD card. I'm fairly certain that if I can get adb to recognize the device, then I can use to see where I am touching the screen and do what I need to do. Problem is, when I plug it in, it's not recognized, while my emulator is. I suspect that I might not have USB debugging enabled, which I think is necessary for adb to work. If this is the case, can someone give me screenshots of their Droid X (running 2.3.X) going from the home screen, through all the menus, to activating debug mode? Hopefully I can do it by dead reckoning and adb from there. Edit: I haven't changed anything about the ROM or launcher; it's all stock." ]

[ "I've been working on some animations recently, and I've noticed that I'm having poor luck with certain things, namely the fact that I don't really use Blender's graph editor very well. One of the major issues that I have is pretty widespread among 3D graphics programs; when I create an animated object, it defaults to using a curved graph instead of a linear graph, which means that the most movement is at the middle of the animation, and stuff just practically stops near the beginning or the end. While this helps with organic camera movements or such, it's also not what I usually want. Can I set animation curves to default to linear?", "List of Stored Procedure from Table I have a huge database with 100's of tables and stored procedures. Using SQL Server 2005, how can I get a list of stored procedures that are doing an insert or update operation on a given table.", "Robust method to extract \"pure\" part of a variable I am trying to perform a multi linear regression model: $$y_i = β_0 + β_1x_{i1} + β_2x_{i2} +... + β_px_{ip} + ε_i$$ where $$x_{i1}, x_{i2}, ..., x_{ip}$$ are highly correlated with each other (VIFs can be as low as 5 and high as 30). I am just wondering if there exists a procedure with the following properties: 1) extracts the pure part of each independent variable, where pure is defined as a part of the variable which is uncorrelated with other variables. 2) the pure part and the original variable should be similar to each other, whether similar is defined as moments such as mean and variance and correlation coefficient (ideally >0.90)", "How to keep any Window \"Always on Top\"? Some software have an option for their window to be \"Always on Top\". Is there any way to get the same functionality for any window. Let me give an example where this would be useful. Suppose I have a small browser window with real time stats from a game. The window is automatically updated at the rate of once every 10 seconds. I would like the small window to be always on top. so that I can just look at it whenever I want to, without actually going to it and at the same time I could continue working in my main application, which is at full screen. Is there any Windows hack or App which can give me this functionality?", "What is DOCTYPE and why do I want to use it? What are the different DOCTYPEs I can use? What is the difference between standards and quirks mode, and what are some quirks I may run into with differently set DOCTYPEs? Lastly, what is the proper DOCTYPE that I should be using?", "I am trying to prove the following statement but have trouble comprehending/going forward with some parts! Here is the statement: If $A$ is any set, then $|A|$ $&lt;$ $|P(A)|$ Here is what I have so far: We need to show that there is an injection from $A$ to $P(A)$ but not a surjection. A natural choice for an injection is the function $ f(x)$ $=$ $\\{x \\}$, which in plain English, takes any element $x$ (that is in $A$) and sends it to the one-element set $\\{x \\}$. Thus $f(x)$ is injective! To show that there is no surjection, for the sake of contradiction, assume there is a surjection. Here is where I start to have trouble. Surjectivity means that every element of the co-domain is mapped to an element of the domain, correct? Consequently, in this particular case, we are \"matching\" sets (from $P(A)$) to elements (from $A$) right? If the above is correct, my problem arises here. I am not sure how to prove that $f$ is not surjective. Unfortunately, I am easily confused by notation so please explain in English. Thank you in advance!! :)", "Idempotents in a ring without unity (rng) and no zero divisors. Question: Given a ring without unity and with no zero-divisors, is it possible that there are idempotents other than zero? Def: $a$ is idempotent if $a^2 = a$. Originally the problem was to show that $1$ and $0$ are the only idempotents in a ring with unity and no zero-divisors, but I wonder what happens if we remove the unity condition. I am trying to find a ring with idempotents not equal to $0$ or $1$. So far my biggest struggle has been coming up with examples of rings with the given properties. Does anyone have any hints? How should I attack this problem?", "Adding Arabic text to an English document", "Natbib puts reference data one line per item I'm using: \\documentclass[oneside,article,openbib,12pt,titlepage]{memoir} \\usepackage[authoryear,round]{natbib} % Better bibliography support \\bibpunct{(}{)}{,}{a}{,}{,} in the preamble of my document and \\backmatter \\renewcommand{\\bibname}{References} \\bibliographystyle{chicago} \\bibliography{listb,mybib} in the body of the file. But a typical formatted reference is: Freely, I. (1997). A small paper. The journal of small papers -1. to appear. I've tried other non-natbib styles (e.g., regstud), and the reference flows and wraps as it should. So how does one get natbib to do the same? Also, how does one get natbib to include the authors' entire first names?", "How to center an element horizontally and vertically", "How does \"Reputation\" work? On Stack Exchange, users may gain a certain level of reputation. What does reputation do? How can a user gain or lose reputation? See also in the Help Center - Maximum amount of votes a user can use in a day and reputation requirements to vote. - How to get an exact overview of the actions that got you your reputation. - A full list of all privileges granted at each reputation level on all sites.", "What's an idiom for doing something in an unnecessarily complicated way? For an example, I'll quote C.S. Lewis' The Voyage of the Dawn Treader: One day the cat got into the dairy and twenty of them were at work moving all the milk out; no one thought of moving the cat. Is there an idiom for this type of situation?", "How can I vertically center a \"div\" element for all browsers using CSS? I want to center a div vertically with CSS. I don't want tables or JavaScript, but only pure CSS. I found some solutions, but all of them are missing Internet Explorer 6 support. &lt;body&gt; &lt;div&gt;Div to be aligned vertically&lt;/div&gt; &lt;/body&gt; How can I center a div vertically in all major browsers, including Internet Explorer 6?", "What is the closed form of $\\int e^{x^2} \\, dx$? How can I do a closed form expansion of $\\int e^{x^2} \\, dx$? Please be specific as to which method I must use.", "Complex differential equation How do I solve $$x'=e^{it}\\overline{x}?$$ This is a complex differential equation, but I don't see how to solve it. Edit: the original ODE is given by $$(x', y')=\\begin{pmatrix}\\cos t&amp; \\sin t\\\\ \\sin t&amp;-\\cos t\\end{pmatrix}(x,y)$$ I want to show that solutions of this ODE do not remain bounded for all $t$, and the idea was to solve the complex equation.", "My question is simple. Let $f(x)=x^3\\sin(\\frac{1}{x}), x\\in \\mathbb{R}$. Is this function uniformly continuous on $\\mathbb{R}$? I think it is not uniformly continuous when $x$ goes to $\\infty$", "I can't seem to get these particular faces to take the UV Mapping. I selected the entire object, entered edit mode, hit U>Unwrap. The rest of the mesh takes the uv wrapping, but not those faces for some reason. It looks normal in solid mode. Does anyone know what could be causing this?", "Only squares instead of letters and numbers are displayed in my calculator and other apps in Ubuntu 18.04", "I'm studying molecular biology and I'm trying to understand an experiment which shows the importance of promoters in the relative transcription level (RT). The image below comes from Rolf Knippers' book \"Molekulare Genetik\" (8th edition). The legend says (among other things): Die erste Zeile gibt die normale \"Wildtyp\"-Sequenz der 5'-flankierenden Region wieder. Which, in english, means something like: The first line repeats the normal wild-type sequence of the 5' flanking region. The column on the right gives the relative transcription (RT) level, 1.0 being the highest possible level of transcription. As we can see, the lines where some parts of the \"5' region\" have been deleted give quite low RT levels, since some regions of the promoter are missing. My questions are the following: 1) According to and , I understand that RNA polymerase reads and uses both coding and non-coding strands in order to synthesize RNA. Therefore, how did they manage to use the sequences strands regions had been deleted to make a polymerase \"read them\" and perform transcription? 2) If the polymerase reads the template strand in the 3' -> 5' sense, shouldn't we talk of \"ATAT box\" or \"TAAC box\" instead of \"TATA\" or \"CAAT\" boxes? Does it mean that the \"promoter\" regions they are using on the graphic above are actually on the coding strand? Thanks a lot for your help.", "How to fix \"The system is running in low-graphics mode\" error?" ]

[ "What are 'return' pins? On a VGA connector, there are numerous 'ground' pins. Three of these are Red return, Green return and Blue return; But why does each color component have its own ground pin?", "I would like to visit Iran as a tourist but I'd also like to visit the USA some time after. I know the relations between the two countries are bad. Is it likely that I'm not allowed to enter the USA after having been to Iran? If it matters, I've never been to either of those countries. I'm a Swiss citizen, an atheist from a Christian background.", "How to access Winter 13's Push Major functionality We are ISV Partners and all of our packaging orgs have been upgraded to Winter 13. One of the features of Winter 13 was supposed to allow us to push major release versions to subscriber orgs. I would have expected it to be in the previously existing \"Push Upgrade\" section of our packaging orgs, but that still only allows pushing patch versions. If it didn't make the final Winter 13 release, I would have expected Salesforce to take it off the release page. Is this something we have to ask to be enabled?", "If $d(x,y)$ is a metric, then $\\frac{d(x,y)}{1 + d(x,y)}$ is also a metric", "This started to happen immediately after I had rebooted the first time after doing a system upgrade. It first starts with a dialogue that says \"System program problem detected\". Then when I try to hit 'report problem' not much happens. I am led through a dialogue that always ends up the problem cannot be solved. I am aware this is not a lot of information, however I'm not sure which information I need to publish and how should I obtain it to debug this problem. Here's a screenshot!", "Set of left cosets is a group Let $N$ be a normal subgroup of $G$. Let $G/N = \\{gN : g \\in G \\}$. Show that the $(G/N, \\circ, 1_{G/N})$ is a group, where: $\\circ : G/N \\times G/N \\rightarrow G/N$ is defined by $(gN \\circ hN) = ghN$ and $1_{G/N} = 1*N$. Thanks for your help.", "Is there a way to determine which features / variables of the dataset are the most important / dominant within a k-means cluster solution?", "How can I copy coverart from flac to opus with ffmpeg I am trying to convert some flac files which all have coverart embedded to opus with ffmpeg. All but the coverart gets copied over just fine, but I find myself unable to move the cover over as well. Tried all sorts of -mapmetadata stuff I could find so far, but no luck, the result is always missing the coverart. While the original .flac reports to have a video stream with the coverart Duration: 00:02:53.51, start: 0.000000, bitrate: 910 kb/s Stream #0:0: Audio: flac, 44100 Hz, stereo, s16 Stream #0:1: Video: mjpeg, yuvj420p(pc, bt470bg/unknown/unknown), 500x500 [SAR 1:1 DAR 1:1], 90k tbr, 90k tbn, 90k tbc the created opus files does not have any graphics: size= 2815kB time=00:02:53.51 bitrate= 132.9kbits/s speed= 104x video:0kB audio:2793kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 0.811556% I tried -vcodec copy, -mapmetadata 0, -mapmetadata 0:s:0 so far, with no luck. Doesnt seem to have anything todo with opus, as I have the same problem converting to aac. So is there a way to get the cover out of the flac file and move it over to the new file in on go using ffmpeg, or do I have to extract it first and then glue it back again later to the new file with extra commands?", "Can I uninstall and reinstall Ubuntu Software Center?", "Combine rows / concatenate rows", "I accidentally moved all folders from root to a subfolder. (/bin, /etc, /home, /lib, /usr... all moved) The only ones that were not moved, since they were in use, are /bak, /boot, /dev, /proc, /sys. Now, any command that I try to execute will simply not happen. I constantly get \"No such file or directory\". I am connected through ssh and through ftp, but I cannot move files through ftp, as direct SU login is disabled. I also have access to the actual server if I need to do something directly from there. I'm assuming I would need to edit a configuration file in order to tell it where to find the /bin folder and that would help me get access again, but I don't know which file that would be or how to do it (since I can't even run chmod to change permissions). Is there any way out of this other than re-installing? I am working on an old version of CentOS. I'm extremely new to the world of Linux, hence this action and the question...", "The Software Center in Ubuntu 16.04 (Gnome Software) shows only part of the packages available. While e.g. apt list qtcreator correctly lists the corresponding package a search in Software Center finds nothing. Is there something misconfigured? I upgraded from 15.10. Until now I have used the old Ubuntu Software Center which worked fine.", "Keyboard shortcut to switch between applications in Mission Control Does Apple have keyboard shortcuts to switch between applications in Mission Control? (Instead of hovering over with the cursor)? e.g., which key combination cal I press to get me from \"preview\" to \"app store?\"", "Zooming to selection in arcpy.mapping and only seeing selected features? I selected data by using select layer by attribute, then I need to only select these selection and zoom in to the selection. my code is this, it can zoom in base on the scale I set, but I see other adjacent polygon that has other Code_No, why? Layer = arcpy.mapping.ListLayers(mxd, \"lyr\", df) arcpy.SelectLayerByAttribute_management(lyr, \"NEW_SELECTION\", \"Code_NO = '%s'\"%mycodeNo) df.extent = lyrLayer1.getSelectedExtent() df.scale *= 2", "How can I make a bootable, unattended USB restore disk? I have a load of 14.04 kiosk systems, halfway across the country. These are horrible little integrated devices. I need to upgrade them all to 16.04 to support a new software stack. do-release-upgrade works half the time. The other half it destroys the install. In addition, the CPUs are really slow and network connections at some sites are also pretty shoddy. So even when it works, upgrading takes a long time. So new plan. I can make a fully-installed system image for each kiosk in Virtualbox, or LXC, or whatever. I need a way to get these images unpacked onto the systems. The main problem here is there are very few technical people available at the other end. And I don't want to fly 200 miles to do this myself. I need something that is almost completely automated and doesn't require a keyboard. I'm imagining a scenario where: I make a system image for each kiosk I make a bootable USB drive for each kiosk and copy on the kiosk image. I label each and post them. At the other end, a staff member with physical access to the USB ports just plugs in the right drive and reboots. The bootable element of this then writes and expands the disk image. It's that \"bootable element\" that I'm looking for. I was expecting that something like this might already exist (for bulk reimaging installations) but it's possible I'm in new territory. Anything that gets my images installed without manual interference (past plugging it in) gets points. As far as I know, options like Clonezilla require somebody with a keyboard to tell it what to do. I need something that doesn't require a keyboard, just gets on and does it.", "Graphing the amount of time a function takes", "The most efficient way to implement an integer based power function pow(int, int) What is the most efficient way given to raise an integer to the power of another integer in C? // 2^3 pow(2,3) == 8 // 5^5 pow(5,5) == 3125", "Let $R$ be a commutative ring and $I_1, \\dots, I_n$ pairwise comaximal ideals in $R$, i.e., $I_i + I_j = R$ for $i \\neq j$. Why are the ideals $I_1^{n_1}, ... , I_r^{n_r}$ (for any $n_1,...,n_r \\in\\mathbb N$) also comaximal?", "How can I correct this code to get an answer?", "If a variable is declared as static in a function's scope it is only initialized once and retains its value between function calls. What exactly is its lifetime? When do its constructor and destructor get called? void foo() { static string plonk = \"When will I die?\"; }" ]

[ "Evaluate $\\lim_{x\\rightarrow 0} \\frac{\\sin (6x)}{\\sin(2x)}$ without L'Hopital", "How to conduct an Accent Sensitive search in MySql I have a MySQL table with utf8 general ci collation. In the table, I can see two entries: abad abád I am using a query that looks like this: SELECT * FROM `words` WHERE `word` = 'abád' The query result gives both words: abad abád Is there a way to indicate that I only want MySQL to find the accented word? I want the query to only return abád I have also tried this query: SELECT * FROM `words` WHERE BINARY `word` = 'abád' It gives me no results. Thank you for the help.", "Word whose form is contrary to its meaning? Is there a word for a word whose form is contrary to its meaning? For example, \"quotidian\" is anything but quotidian.", "Monitoring contents of files/directories?", "Background: I'm giving a presentation to colleagues at work on hypothesis testing, and understand most of it fine but there's one aspect that I'm tying myself up in knots trying to understand as well as explain it to others. This is what I think I know (please correct if wrong!) Statistics that would be normal if variance was known, follow a $t$-distribution if the variance is unknown CLT (Central Limit Theorem): The sampling distribution of the sample mean is approximately normal for sufficiently large $n$ (could be $30$, could be up to $300$ for highly skewed distributions) The $t$-distribution can be considered Normal for degrees of freedom $&gt; 30$ You use the $z$-test if: Population normal and variance known (for any sample size) Population normal, variance unknown and $n&gt;30$ (due to CLT) Population binomial, $np&gt;10$, $nq&gt;10$ You use the $t$-test if: Population normal, variance unknown and $n&lt;30$ No knowledge about population or variance and $n&lt;30$, but sample data looks normal / passes tests etc so population can be assumed normal So I'm left with: For samples $&gt;30$ and $&lt;\\approx 300$(?), no knowledge about population and variance known / unknown. So my questions are: At what sample size can you assume (where no knowledge about population distribution or variance) that the sampling distribution of the mean is normal (i.e. CLT has kicked in) when the sampling distribution looks non-normal? I know that some distributions need $n&gt;300$, but some resources seem to say use the $z$-test whenever $n&gt;30$... For the cases I'm unsure about, I presume I look at the data for normality. Now, if the sample data does looks normal do I use the $z$-test (since assume population normal, and since $n&gt;30$)? What about where the sample data for cases I'm uncertain about don't look normal? Are there any circumstances where you'd still use a $t$-test or $z$-test or do you always look to transform / use non-parametric tests? I know that, due to CLT, at some value of $n$ the sampling distribution of the mean will approximate to normal but the sample data won't tell me what that value of $n$ is; the sample data could be non-normal whilst the sample mean follows a normal / $t$. Are there cases where you'd be transforming / using a non-parametric test when in fact the sampling distribution of the mean was normal / $t$ but you couldn't tell?", "Backquote in lsblk output What does ` mean in this output from lsblk?", "Should 'fuck' be present in review audits (intentionally fake suggested edit reviews)?", "When to use virtual destructors? I have a solid understanding of most OOP theory but the one thing that confuses me a lot is virtual destructors. I thought that the destructor always gets called no matter what and for every object in the chain. When are you meant to make them virtual and why?", "Got NODATA issue: 'NODATA' (does the network require authentication?)", "I often need to make banner sets that consist of anywhere from 6-14 different sized banners. A lot of these banners have the same text (which I put in smart objects to work faster) and the same or different images. The placement and sizes of these elements differ according to the banner size though. I find the process of 'copying' the content from one artboard to another to go a bit slower than I'd like it to. I can't simply copy/paste, I have to duplicate the layer and then drag it to the right artboard in the layer panel. Hoping I have closed all my folders or else I have to drag miles upwards ;) There has to be a better way! Why can't I simply copy paste a layer anymore? I'm pretty sure this used to be the case in older versions of photoshop.", "Cannot install a version of GDAL via Anaconda that permits reading BigTIFFs", "Are drops in Google ranking common after switching to https? About a week ago I made the switch to https on one of my sites. I'm positive I did everything right. Properly setup 301 redirects from http to https versions. Added and verified https version in Webmaster Tools. Updated all internal links. Submitted new sitemap. Despite that, many of my pages (about 40%) lost their rankings almost immediately. Those that dropped went from page 1 to nowhere. I can still see them indexed if I search for the URL, but otherwise it's like Google doesn't know they exist. SSL Labs shows an \"A\" when I run their test and I have no manual actions showing in Webmaster Tools. This is really frustrating. I don't actually need SSL, but Google finally scared me into it. Now I'm regretting the switch and contemplating going back to non-secured URLs. Anything else I could have missed?", "How do I color intersection of two ellipses in different color. For instances, the ellipses should themselves be colored as yellow and their intersection as red. My code for drawing ellipses is given below \\draw (-4,0) ellipse (8 and 3); \\draw (8,0) ellipse (8 and 3); UPDATE: In the comments to individual answers, I have requested to show it for three ellipses.", "I've been wondering what makes the such an important model. What I came up with: It is a (relatively) simple system, making it a perfect example for physics students to learn principles of classical and quantum mechanics. The harmonic oscillator potential can be used as a model to approximate many physical phenomena quite well. The first point is sort of meaningless though, I think the real reason is my second point. I'm looking for some materials to read about the different applications of the HO in different areas of physics.", "What is the difference between 'su -' , 'sudo bash' and 'sudo sh'? I would like to know what is the difference between su - sudo bash sudo sh I cannot login as root while doing su - because I do not have the root password - I mean I have my user password with which I can sudo \"command\" but this password does not work for su - I can log in as root with sudo bash with my user password and I can login while doing sudo sh but then I get a command prompt in this form #", "How do I get past the \"do not enter\" traffic sign that stops me from installing \"Sierra\" instead of \"High Sierra\"? I booted into rescue mode and deleted the original \"High Sierra\" installation, but booting from the USB stick with the \"Sierra\" installer on it still gives me the \"no\".", "What are some good introductions to philosophy? I've been searching the questions posed here, and don't seem to find one that gives the answers I am looking for. I've proposed to start a on meta but no one proposed anything, so I feel I must ask this question: What are some books generally regarded as good for a general introduction on philosophy? By this I mean good books that can introduce you to philosophy in general and throughout the times, not to some philosophy or period in particular. almost answers mine, except for the fact that most things proposed there are not books, thus not giving me much options to weigh upon. regards contemporary philosophy in particular. And has the same problem as the first one, plus the fact that it asks for layman's terms, which is not what I am looking for. I've been tempted to buy Will Durant's , but am not sure if it is the best book to get started on philosophy (plus, the book has some mixed reviews). I also checked , which seems to be unanimously good, but has the format of dictionary/encyclopaedia, which is not exactly what I am looking for (at least as a main source). also seems to be a good introduction regarding how to do philosophy, rather than to its history and ideals (this also interests me, but I'd rather learn about the philosophers and their theories first). It is also important to point out that I have little notions (or none at all) on philosophy. I would like to read something that covers from classical to contemporary philosophy generally (although I do not know if there is such a book), so that from there I could pick some author, period or branch of philosophy in particular to read further on. So, to sum up, I would like to 'hear' your opinions on what are some books generally regarded as good for a general introduction on philosophy.", "I did a bit of math at school and it seems like an easy one - what am I missing? $$n\\times m = \\underbrace{n+n+\\cdots +n}_{m\\text{ times}}$$ $$\\quad n\\times 0 = \\underbrace{0 + 0 + \\cdots+ 0}_{n\\text{ times}} = 0$$ (i.e add $0$ to $0$ as many times as you like, result is $0$) So I thought an infinite number of $0$'s cannot be anything but $0$? But someone claims different but couldn't offer a reasonable explanation why. Google results seemed a bit iffy on the subject - hopefully this question will change that.", "Seem to have lost 4 Silver badges and 10 Bronze badges", "How to host a single website on multiple servers? I'm planning on releasing an iOS app that downloads video from my server. If hundreds of people on the launch day try to do this, then my website and the services that my server provides will clearly go down. How do you host a website on multiple servers? When someone tries to access my site, how is their request passed to an available server? How do Apple and Google do it? Thanks for your help." ]

[ "No custom off topic message when flagging on SO I have less than 3000 rep on StackOverflow. Now that the new closing changes are live, I cannot supply a custom off topic message: I can enter a custom off topic flag message without issue here on meta, though it only has three canned off topic reasons, rather than five. I'm not sure if this is the same for users with enough rep to vote to close directly, but the lack of a custom message eliminates the ability to use the correct flag reason in some cases. For example, I wanted to flag , which is simply off topic on SO. However, I can't use a custom message, and none of the canned ones are appropriate. appears to be the most up to date official information on custom reasons, and indicates that they are remaining in play for now. supports that. If this is by design, how should I flag such questions? This is not a case worth bothering the mods over, so I don't want to use a custom diamond attention flag.", "difference between accuracy and Rand index (R) I'm very confused, when I read on the wikipedia \"From a mathematical standpoint, Rand index is related to the accuracy, but is applicable even when class labels are not used.\" and But when I use in R the rand.index function from fossil package and the Accuracy function from MLmetrics it doesn't give the same answer &gt; Accuracy(predicted, real) [1] 0.8266667 &gt; rand.index(predicted,real) [1] 0.7114989 Please can someone explain to me the difference between these two and which one should I use? NB:I use the k-medoids clustering algorithm (function pam from cluster package)", "What is scientific mind?", "Terms for collections of animals As I watched the murder of crows sitting on the line above my house this evening, I got wondering where all of the collective nouns for animals (pod of whales, gaggle of geese, pride of lions) came from and why we need so many. If sheep can be a flock, why can't whales, geese, lions, and crows?", "I know that symlinks have a separated inode from the original file and that they only point for the inode containing the data. My question is, where is the hardlink name stored if there's no field in the inode structure refering to \"name\". I know that this could be a a relatively easy question, but as all hardlinks have the same inode number i assume that no inode is created when creating a hard link.", "proving logical equivalence $(P \\leftrightarrow Q) \\equiv (P \\wedge Q) \\vee (\\neg P \\wedge \\neg Q)$ I am currently working through Velleman's book How To Prove It and was asked to prove the following $(P \\leftrightarrow Q) \\equiv (P \\wedge Q) \\vee (\\neg P \\wedge \\neg Q)$ This is my work thus far $(P \\to Q) \\wedge (Q \\to P)$ $(\\neg P \\vee Q) \\wedge (\\neg Q \\vee P)$ (since $(P \\to Q) \\equiv (\\neg P \\vee Q)$) $\\neg[\\neg(\\neg P \\vee Q) \\vee \\neg (\\neg Q \\vee P)]$ (Demorgan's Law) $\\neg [(P \\wedge \\neg Q) \\vee (Q \\wedge \\neg P)]$ (Demorgan's Law) At this point I am little unsure how to proceed. Here are a few things I've tried or considered thus far: I thought that I could perhaps switch some of the terms in step 3 using the law of associativity however the $\\neg$ on the outside of the two terms prevents me from doing so (constructing a truth table for $\\neg (\\neg P \\vee Q) \\vee (\\neg Q \\vee P)$ and $\\neg (\\neg P \\vee \\neg Q) \\vee \\neg (P \\vee Q)$ for sanity purposes) I can't seem to apply the law of distribution since the corresponding terms are negated. Applying demorgans law to one of the terms individually on step 2 or 3 doesnt seem to get me very far either. Did I perhaps skip something? Am I even on the right track? Any help is appreciated", "Which form should be used for at­tribu­tive nouns like “stu­dent union”: sin­gu­lar or plu­ral, or pos­ses­sive sin­gu­lar or pos­ses­sive plu­ral? When should a noun that’s used at­tribu­tively to de­scribe an­other noun be plu­ral, and when should it be sin­gu­lar? And when should it be pos­ses­sive, like bak­er’s dozen and when should it be plu­ral pos­ses­sive, like farm­ers’ mar­ket? In other words, why do we say teach­ers union rather than teacher union? And why do we say wed­ding plan­ner rather than wed­dings plan­ner? Which of these vari­ants is or are cor­rect? stu­dent union stu­dents union stu­den­t’s union stu­dents’ union What about com­mu­nity val­ues ver­sus com­mu­ni­ty’s val­ues? Please note I am look­ing for a gen­eral rule or at least some tips. These are only ex­am­ples. Up­date: It seems even na­tive speak­ers fol­low their per­sonal style to write such com­pound words. I won­der why in the IELTS lis­ten­ing sec­tion, the lan­guage learner has to write a spe­ci­fic form and there is no rule for this.", "Blender 2.78 with Windows 10 lags when interacting with the UI", "How do we see? Where do the photons disappear?", "Brasero says it won't burn the CD because the file is too big, what's going on?", "Last seen not updating when using Android app This isn't directly related to the app, but probably more on the APIs it's using. The last seen on the profile page doesn't seem to reflect that I'm actively using the Android app, or taking actions. I was able to vote on items and the last seen property on the profile page said I was last seen 50 minutes ago, when I was using a computer. I'm assuming it won't count as a visit for the Enthusiast and Fantic badges either. I don't want someone angrily posting on Meta swearing they used the app for a day, yet they lost the consecutive days and has to prove it by showing they voted for something (we're probably far from this situation since it's alpha...)", "JavaScript private methods To make a JavaScript class with a public method I'd do something like: function Restaurant() {} Restaurant.prototype.buy_food = function(){ // something here } Restaurant.prototype.use_restroom = function(){ // something here } That way users of my class can: var restaurant = new Restaurant(); restaurant.buy_food(); restaurant.use_restroom(); How do I create a private method that can be called by the buy_food and use_restroom methods but not externally by users of the class? In other words, I want my method implementation to be able to do: Restaurant.prototype.use_restroom = function() { this.private_stuff(); } But this shouldn't work: var r = new Restaurant(); r.private_stuff(); How do I define private_stuff as a private method so both of these hold true? I've read a few times but it doesn't seem like \"private\" methods can be called by public methods and \"privileged\" methods can be called externally.", "80's Animated movie: An old man joins mission to save a boy stranded on a hostile world", "sort() and reverse() functions do not work", "How to add Excel sheet to console application", "How can I determine how much bleed to use?", "ORA-00918: column ambiguously defined in SELECT *", "I like to be thorough, but if you feel confident you can skip the first paragraph. Review: A ring is a set $R$ endowed with two operations of + and $\\cdot$ such that $(G,+)$ is an additive abelian group, multiplication is associative, $R$ contains the multiplicative identity (denoted with 1), and the distributive law holds. If multiplication is also commutative, we say $R$ is a commutative ring. A ring that has no zero divisors (non-zero elements whose product is zero) is called an integral domain, or just a domain. We want to show that for a domain, the equation $x^2 = 1$ has at most 2 solutions in $R$ (one of which is the trivial solution 1). Here's what I did: For simplicity let $1,a,b$ and $c$ be distinct non-zero elements in $R$. Assume $a^2 = 1$. We want to show that letting $b^2 = 1$ as well will lead to a contradiction. So suppose $b^2 = 1$, then it follows that $a^2b^2 = (ab)^2 = 1$, so $ab$ is a solution as well, but is it a new solution? If $ab = 1$, then $abb = 1b \\Rightarrow a = b$ which is a contradiction. If $ab = a$, then $aab = aa \\Rightarrow b = 1$ which is also a contradiction. Similarly, $ab = b$ won't work either. So it must be that $ab = c$. So by \"admitting\" $b$ as a solution, we're forced to admit $c$ as well. So far we have $a^2 = b^2 = c^2 = 1$ and $ab = c$. We can procede as before as say that $(abc)^2 = 1$, so $abc$ is a solution, but once again we should check if it is a new solution. From $ab = c$, we get $a = cb$ and $b = ac$, so $abc = (cb)(ac)(ab) = (abc)^2 = 1$. So $abc$ is not a new solution; it's just one. At this point I'm stuck. I've shown that it is in fact possible to have a ring with 4 distinct elements, namely $1,a,b$ and $c$ such that each satisfies the equation $x^2 = 1$ and $abc = 1$. What am I missing?", "ReSharper likes to point out multiple functions per ASP.NET page that could be made static. Does it help me if I do make them static? Should I make them static and move them to a utility class?", "How do I disable DVD auto eject in Windows 7? I just discovered an incredibly annoying \"feature\" of Windows 7 tonight. If you click on your optical drive in Explorer, and there is no disc in the drive, Windows 7 is kind enough to open the tray for you. I'm finding it hard to contain my rage over this idiotic design decision. WTF? According to , this behavior was apparently introduced in Vista. The author posted a workaround, but I don't want a workaround. I want it to stop doing this. Like he, I have a case with a door that covers the drive bays. If it's closed, and I accidentally click on that optical drive, it knocks on that door 10 or 12 times before giving up. Can this behavior be turned off in Windows 7?" ]

[ "$k$ times's draw from $n$ numbers with replacement, each number at least appear once Sample $k$ times with order from $n$ distinct numbers with replacement where $k\\ge n$. Here \"with order\" means the sample is treated like a sequence rather than a set, so results like \"1,3,3\" and \"3,1,3\" are different. The question is what is the probability that every number is sampled at least once? My answer is $1-\\frac{{\\sum\\limits_{i = 1}^n {C_n^i\\times i! \\times {{(n - i)}^k}} }}{{{n^k}}}$ where $C_n^i$ denotes $n$ chooses $i$. ${C_n^i\\times i! \\times {{(n - i)}^k}}$ means first choose $i$ ($i=1,2,...,n-1$) of numbers not to appear in the sample, and then we sample from the remaining $n-i$ numbers for $k$ times. My question is, is there more elegant solution where the numerator can be directly computed? i.e. can we directly calculate the number of possible sample sequences in which every number has at least one occurrence? Thank you! PS: my attempt was $C_k^n\\times n!\\times n^{n-k}$, meaning that we first choose $n$ positions in the sequence of length $k$ to place $n$ numbers, and then permute the $n$ numbers. This is to ensure every number to appear once. The remaining $n-k$ are sampled from the $n$ numbers without restriction. However, I later found this seems not correct, and it counts the same sequence multiple times. PS2: as pointed out in the comments, my first answer \"1- ...\" is not correct either.", "Getting around the FAT32 4GB file size limit", "I've got a repo that I contribute to within an Organization that I administer. I'm trying to add it to careers, but it won't allow it. Is this on purpose? I don't really want to fork it to my personal account, since I won't be maintaining it from there.", "Entire function with vanishing derivatives? Let $f:\\mathbb{C}\\rightarrow\\mathbb{C}$ be an entire function. And assume that at each point, one of it's derivatives vanishes. What can you say about $f$? A hint suggests that $f$ must be a polynomial.", "Which form should be used for at­tribu­tive nouns like “stu­dent union”: sin­gu­lar or plu­ral, or pos­ses­sive sin­gu­lar or pos­ses­sive plu­ral? When should a noun that’s used at­tribu­tively to de­scribe an­other noun be plu­ral, and when should it be sin­gu­lar? And when should it be pos­ses­sive, like bak­er’s dozen and when should it be plu­ral pos­ses­sive, like farm­ers’ mar­ket? In other words, why do we say teach­ers union rather than teacher union? And why do we say wed­ding plan­ner rather than wed­dings plan­ner? Which of these vari­ants is or are cor­rect? stu­dent union stu­dents union stu­den­t’s union stu­dents’ union What about com­mu­nity val­ues ver­sus com­mu­ni­ty’s val­ues? Please note I am look­ing for a gen­eral rule or at least some tips. These are only ex­am­ples. Up­date: It seems even na­tive speak­ers fol­low their per­sonal style to write such com­pound words. I won­der why in the IELTS lis­ten­ing sec­tion, the lan­guage learner has to write a spe­ci­fic form and there is no rule for this.", "How to generate a simple cartesian plane system? I need to make a cartesian plane for plotting the straight line joining the points (-3,1) and (6,-2). This is a very simple cartesian plane plotting. When I looked at the manual for tikz the graphics for cartesian planes are for more advance plotting, and what I need is very simple. Something like this:", "There are many addons. Do you know how show it in two cloumns?", "Geometric proof that a Pythagorean triple has a number divisible by $3$? Can I infer from “If $a,b \\in \\mathbb{N}$ such that $(a,3)=(b,3)=1$ then $a^2+b^2\\neq c^2$ for any $c\\in\\mathbb{N}$” that any pythagorean triple has a number which is divisible by $3$? If so, how can this relationship be proved geometrically?", "Why multiple capacitors in parallel? Wondering why you would choose to use smaller capacitors in parallel vs one bigger one. Here's an example: Is this a component size and track width choice? Thanks!", "Prove that 10101...10101 is NOT a prime. So basically we have a number $10101...10101$ that contains $2016$ zeros and can be written as$ \\sum _{ k=0 }^{ 2016 }{ 100^{ k } }$ . I want to prove that this number is not a prime without using anything besides a piece of paper and a pen. I'm stuck on this for quite a few days now.", "Get PHP to stop replacing '.' characters in $_GET or $_POST arrays? If I pass PHP variables with . in their names via $_GET PHP auto-replaces them with _ characters. For example: &lt;?php echo \"url is \".$_SERVER['REQUEST_URI'].\"&lt;p&gt;\"; echo \"x.y is \".$_GET['x.y'].\".&lt;p&gt;\"; echo \"x_y is \".$_GET['x_y'].\".&lt;p&gt;\"; ... outputs the following: url is /SpShipTool/php/testGetUrl.php?x.y=a.b x.y is . x_y is a.b. ... my question is this: is there any way I can get this to stop? Cannot for the life of me figure out what I've done to deserve this PHP version I'm running with is 5.2.4-2ubuntu5.3.", "Problem. Assume that $U$ is an open and connected subset of $\\mathbb R^2$, and $\\gamma :[0,1]\\to U$ is a closed curve, which is not null-homotopic in $U$ and not necessarily simple closed. Show that there exists a simple closed curve, which is not null-homotopic in $U$. I am sure that this is a standard problem, and I am looking for an elegant, if possible, solution or a reference. I have in mind the following sketch of proof: a. Construct a polygonal closed curve $\\tilde\\gamma$ which is homotopic with $\\gamma$ in $U$. b. Construct $\\tilde\\gamma$ so that it intersects itself in finitely many points, and not whole segments. c. Use induction on the number of self–intersections of $\\tilde\\gamma$, in order to show that $\\tilde\\gamma$ is written as a product (in the fundamental group's sense) of simple closed polygonal curves.", "Order discrete x scale by frequency/value", "OK...before everyone blasts this with references to the relativistic invariance of the physical laws, time dilation, etc let me add some context. Also, I am an amateur with an interest in physics, so I don't know the details of the physics. However, I have read enough about the cosmological principle and cosmic time to develop this \"confusion\" . Based on evidence gathered to-date, it appears that the universe is both , as evidenced by observations and the . This principle, when combined with the FLRW metric, allows space-time to be divided into non-intersecting slices and therefore establish a \"cosmic time.\" Now, the existance of such a time in no way suggests that it is the \"right\" time or a true \"now\", hence violating relativity -- although some presentist philosophers (e.g., W.L. Craig) have tried to make this argument, but it is not generally accepted in philosophical circles. However, this leaves me confused about an apparent disconnect between relativity and the cosmological principle: Isotropy only holds if we are at rest relative to the cosmic microwave background radiation (universal rest frame), o/w anisotropy is present - yet each reference frame is supposed to allow equally valid observations. How can these two be reconciled when most reference frames would lead us to conclude that the universe is NOT isotropic? It seems that only by appealing to the idea of being at rest relative to \"universal rest frame\" can we explain away any discrepancies from isotropy as due to \"peculiar motion\". However, doesn't this give this \"universal rest frame\" and its associated time an empirically privileged status, even though physical laws work just fine in every reference frame? For example (pardon any abuse of astronomy): if look off in some part of space and see only quasars, and then in another part of space and see only brown dwarfs, but I measure both as apparently the same distance from me, then can I conclude that we are in motion, since otherwise we would have an empirical contradiction (kind of like finding dinosaur and human remains in the same strata)? Any help on where I am going wrong would be helpful. Intuitively, I don't think there should be a way to establish absolute ordering between space-like separated events, but the above reasoning suggests otherwise.", "I'm writing my final report in LaTeX for my bachelor's degree. I'm aiming at having a document similar to the .doc template used normally. I want to have my customs headers and footers applied on pages when I'm starting a new chapter. I'm using documentclass report with fancyhdr and lastpage packages. My headers are defined like this: \\lhead{\\myTitle} \\rhead{\\today} \\cfoot{\\thepage\\ of \\pageref{LastPage}} My chapters are created using standard \\chapter{title} macro. On pages with new chapters, the only headers/footers I see is the standard page number at the bottom. What should I do? EDIT: I've finally gone with Peter Breitfeld's solution. I'Ve gone a step further and created my own chapter command: \\newcommand{\\myChapter}[1]{ \\chapter{#1} \\thispagestyle{fancy} } Thanks for the help!", "How many 6-letter permutations can be formed using only the letters of the word, MISSISSIPPI? I understand the trivial case where there are no repeating letters in the word (for arranging smaller words) but I stumble when this isn't satisfied. I'm wondering if there's a simpler way to computing all the possible permutations, as an alternative to manually calculating all the possible 6-letter combinations and summing the corresponding permutations of each. In addition, is there a method to generalize the result based on any P number of letters in a set with repeating letters, to calculate the number of n-letter permutations? Sorry if this question (or similar) has been asked before, but if it has, please link me to the relevant page. I also apologize if the explanation is unclear, or if I've incorrectly used any terminology (I'm only a high-school student.) If so, please comment. :-)", "In Greek, λογικοφανής is a word that describes a person who spits out seemingly logical statements. It often has a negative connotation as it is targeted towards people who tend to fool the public with supposedly beautifully-constructed thoughts that sound convincing in our ears but are not necessarily accurate. The first word that comes to mind is deceptive, but it is not quite what I look for. Any thoughts?", "How to start applications such as xcompmgr at start up? I've been trying to make xcompmgrto autostart in Lubuntu 11.10 but it just doesn't, I have to start it manually. I have added the next lines to the autostart script in ~/.config/openbox/ #Run a composite manager xcompmgr &amp; But whenever I log in it doesn't do anything, I don't really need any special parameters for it I just want it to start at log in. How can I make it run automatically at login?", "While I can post external texts into question and answer bodies, it preserves the old font style, spacing and size (although the markdown display won’t be affected by that.) App Version: 1.6.6.2 Device: iPhone 6 OS Version: Version 11.0.3 (Build 15A432)", "I am having a problem with Windows 7. When I boot up, the CPU jumps to 100% execution for about 10-15 minutes. During this time, it is really slow, and if I play any music, the songs play slowly and sound distorted. I tried to scan my computer with different antivirus programs, I used Spybot, HijackThis, and CCleaner, but I didn’t find anything of note. I watched the process list in Task Manager and saw that there are two processes that are to blame. There are two copies of svchost.exe, one using ~48% CPU, the second (under the Network Service account) using ~37%. For the first 15 minutes, the CPU runs at about 70-80%, then eventually drops to 30-40%. I don’t know what to do. I could not find a way to stop the services, and if I try to kill them, sometimes the system crashes." ]

[ "Count how many lines start with which characters I have a file with a number of lines in a file filename. I want to count how many lines start with character 'a', with 'b' and so on in one go. What command i should execute.?", "Easy way to change apache www location", "How to use PostgreSQL/PostGIS with ArcGIS for Desktop?", "Why won't any faces show up in the UV Image Editor?", "Quickly create a large file on a Linux system How can I quickly create a large file on a Linux () system? will do the job, but reading from /dev/zero and writing to the drive can take a long time when you need a file several hundreds of GBs in size for testing... If you need to do that repeatedly, the time really adds up. I don't care about the contents of the file, I just want it to be created quickly. How can this be done? Using a sparse file won't work for this. I need the file to be allocated disk space.", "When does $P(x)=\\sum_{n=0}^{\\infty}{\\frac{n!}{n^n}\\cdot x^n}$ with $x\\in \\mathbb{C}$ converge?", "How do I obtain the ebony blade and how do I power it up? The ebony blade is a katana like two handed weapon in Skyrim. Its apparently associated with one of the daedric quests, but which one, and how do I start it? Also, once I obtain it, how do I power it up?", "Sometimes, others just inform us about things without us asking them, other times they do not do that even if we ask them. I want a verb for when others do not give us information — whether because they do not like to or they just don't give it, but we cannot directly ask them to — but we actively extract the information from them sometimes without them being aware of it. So the word I am looking for shouldn't be only for cases where we coerce or force others to give us information, and it shouldn't be only for cases where others do not like to give us information. Example: I needed that information. But I couldn't ask her for it, or most probably she would not give to me even if I asked her. So, I .... the information I wanted. It could be a phrasal verb and so not just a single word, but I couldn't devise a blank suitable for all possibilities! Two verbs I've already had but I think are not suitable: to give someone the third degree To prize something from/out of somebody", "Prove Equivalence Relation in G Hei, guys! I'm having some trouble with the next problem: Let $A$ and $B$ be subgroups of $G$. Show that $\\sim$ is an equivalence relation when it is defined as follows: $g\\sim g'\\Leftrightarrow g' = agb$ for some $a$ from $A$, $b$ from $B$. Should I prove this is valid for any a and b? It says for some elements a and b. But I might as well take the unit element. Could you give me a clue on how to solve it? Cheers!", "\"A/An\" preceding a parenthetical statement", "Anime about a boy and a girl who ride ostrich-like creatures through a valley", "I intend to use fsck for checking my Linux partition of the main disk, because its file system is suspicious of being not unmounted cleanly by shutting down the system. I have searched in my environment variables: none of them except of PATH should control the fsck program. But the program apparently needs to be used during a boot: :~$ fsck -V fsck from util-linux 2.20.1 Checking all file systems. [/sbin/fsck.ext4 (1) -- /] fsck.ext4 /dev/sda6 e2fsck 1.42 (29-Nov-2011) /dev/sda6 is mounted. WARNING!!! The filesystem is mounted. If you continue you WILL cause SEVERE filesystem damage. Do you really want to continue? no check aborted. (There is no /forcefsck file in my root according to . My etc/fstab file contains # /etc/fstab: static file system information. # # Use 'blkid' to print the universally unique identifier for a # device; this may be used with UUID= as a more robust way to name devices # that works even if disks are added and removed. See fstab(5). # # proc /proc proc nodev,noexec,nosuid 0 0 # / was on /dev/sda6 during installation UUID=1ac55d8d-c112-4bc7-9e79-921d196f9f79 / ext4 errors=remount-ro 0 1 # swap was on /dev/sda7 during installation UUID=54f7e314-50e2-419b-a45d-47c3058ecc00 none swap sw 0 0 /dev/fd0 /media/floppy0 auto rw,user,noauto,exec,utf8 0 0 ). According to an answer to I have tried tune2fs hoping that I'll get the present value of the max_mounts_count parameter to be able to set it to 1 for checking the partition during the next boot. But after sudo rm /var/lib/update-notifier/fsck-at-reboot and a restart I have only got a response :~$ tune2fs -l /dev/sda6 tune2fs 1.42 (29-Nov-2011) tune2fs: Permission denied while trying to open /dev/sda6 Couldn't find valid filesystem superblock. Can I use sudo tune2fs -l /dev/sda6 safely? Thanks.", "Unable to disable Hyper-V in Windows 10 Hi I installed Docker for Windows which enabled Hyper-V on my windows 10 machine. Unfortunately this caused Virtual Box to not work anymore, therefore I removed Docker again, but Hyper-V is still activated. If I try to disable Hyper-V with any of those ways: on the reboot it will first try to apply the changes and than say that the changes couldn't be applied and reverts, so Hyper-V is activated again. Has anybody an idea what could be the issue here?", "The locker problem - why squares? There are 1000 lockers in a high school with 1000 students. The problem begins with the first student opening all 1000 lockers; next the second student closes lockers 2,4,6,8,10 and so on to locker 1000; the third student changes the state (opens lockers closed, closes lockers open) on lockers 3,6,9,12,15 and so on; the fourth student changes the state of lockers 4,8,12,16 and so on. This goes on until every student has had a turn. How many lockers will be open at the end? I worked out this problem by doing it for 10 lockers. The pattern was obvious (1,4,9 remained open).It's easy to then say that 31 lockers remain open at the end. I don't quite understand why only square numbers remain open at the end. Is there some deeper reason?", "What if the Earth stops in its orbit and instead falls straight towards the Sun? The Earth orbits around the Sun because it has angular momentum. If we stopped the Earth in orbit and then let it fall straight towards the Sun, how long would it take to reach the Sun in seconds? Details and assumptions The mass of the sun is 2*10^30 Kg. The mass of the earth is 6*10^24 Kg. The earth is 149,600,000 Km from the Sun. You may treat the Earth and Sun as point masses.", "In another regarding a difference between short on and short of, the says the following: ... But this is not always the case. A person can be short on/of money, but lacking a specific amount, someone can only be €10 short or short €10. This construction never uses a preposition. but is that really true? I can see sentences like \"I am short of 10 dollars\" quite often.", "How to change Power button shutdown action to run a script under systemd How does one change the power button shutdown action under say debian 10 systemd to run a custom script instead of shutting down the system? Back when this was handled by acpi one could edit the scripts in /etc/acpi. The only suggestion I have found thus far is to replace various power related binaries with my script. Is there a way to do this without replacing binaries?", "Do I have to enter the UK on my UK passport?", "How do I enumerate the properties of a JavaScript object?", "Pass shell variable as a /pattern/ to awk" ]

[ "Continuous and bounded variation does not imply absolutely continuous", "How to setup two completely separate partitions on one SSD I have a MacBook with 1TB SSD. I want to have two separate partitions with two independent macOS installations. I want to make sure that none of the partitions have any kind of possibility to interact with the other, I want them to be as separated as if they were physically separate. Is this achievable with, for example, FileVault for each of them? Edit: My question is neither &quot;how can I install two different macOS versions on two different partitions on one SDD&quot;, neither &quot;how do I use FileVault&quot;, etc. I know how to do all of that. I want to make sure that there is no interaction between the partitions possible. Can this be made sure with the above approach? Is it sufficient?", "Suspended user cannot award bounty I asked a question on Stack Overflow: . I want to award my bounty to by user However, my Stack Overflow account is suspended recently for 7 days, and the suspension still has 5 more days to end.And I know I can't vote, ask, answer or comment as pointed on by with the sentence below. You will be unable to vote, ask, answer, or comment. I couldn't find anything about not being able to accept an answer or award bounty so I tried to accept the mentioned answer above and award my bounty to it and I got a Suspended users cannot vote rejection which can be seen below with a screenshot. I know this If you do not award your bounty within 7 days, the highest voted answer created after the bounty started with at least 2 upvotes will be awarded half the bounty amount. from . None of the answer given to my question is upvoted and the answer I mentioned is not the oldest one after the bounty started so it won't be awarded by community. What can I do? (except being a good guy and not get suspended :))", "short view distance in 3d view?", "pgfplots and using axis cs to add points I am trying to mark two inflection points using a foreach loop in a pgfplot, but it isn't working. \\documentclass[tikz]{standalone} \\usepackage{pgfplots} \\pgfplotsset{compat = 1.10} \\begin{document} \\begin{tikzpicture} \\pgfmathsetmacro{\\infx}{1/sqrt(2)} \\pgfmathsetmacro{\\infy}{exp(-.5)} \\begin{axis}[ xmin = -3, xmax = 3, ymin = -0.1, ymax = 1.05, domain = -4:4 ] \\addplot[blue, samples = 500, smooth] gnuplot {exp(-x^2)}; \\foreach \\x/\\y in {\\infx/\\infy, -\\infx/\\infy}{ \\draw[red] (axis cs: \\x, \\y) circle[radius = .025]; } \\end{axis} \\end{tikzpicture} \\end{document} I am being told: Undefined control sequence.^M &lt;argument&gt; axis cs: \\x ^M , \\y ^M l.34 \\end{axis}^M", "In some text it is given that we can't assign constant values to a reference variable. When I executed such a program I could do it. Is there any condition we can't assign a constant value to a reference variable?", "How do I see that $$f_{n+1}f_{n-1} = f_n^2 + (-1)^n$$ for $n \\ge 2$, where $f_1 = 1$, $f_2 = 1$, and $f_{n+2} = f_{n+1} + f_n$ for $n \\in \\mathbb{N}$?", "Dihedral group - elements of order $2$ If $D_{n}$ is the Dihedral group of degree $n$ (order $2n$) where n is an odd number, can I then conclude that the numbers of elements of order 2 in $D_{n}$ is equal $n?$ I suppose there are the following types of elements in $D_{n}$: b, $a^{i}$, $a^{i}b$ for some $0\\leq i &lt; n$ .", "One of the assumptions I make as GM is that the players should always be in the spotlight. Sometimes the players find themselves in a situation where they watch NPCs speak to each other. I don't like using this kind of situation, because it forces the players to watch me talk to myself and that turns them from active participants into an audience. Usually I handle it by avoiding the situation. I try not to write scenes that the players watch. Instead the players speak to the NPCs one at a time. When I do come across an exchange between NPCs I opt to summarize the conversation instead of acting it out. I don't like this limitation though. It gets a little contrived when all conversations in the game feature 5 PCs and 1 NPC. Any suggestions? Either how to avoid doing it, or how to effectively role play a conversation between two (or more) NPCs that the characters may or may not be interacting with? How do you keep clear which character is speaking? How do you make sure that the conversation feels like a real one and not like one person playing both roles?", "How to correctly add a path to PATH?", "Find html element which id starts with", "Transitivity check vs. Transitive Closure Is checking transitivity of a digraph not easier than (in terms of asymptotic complexity) taking the transitive closure of the digraph? Do we know any lower bound better than $\\Omega(n^2)$ to determine if a digraph is transitive or not?", "There have been for a while, but this is ridiculous. It reminds me of , but this time it's network-wide. The banner must be scrolled past (or dismissed) on every page unless both first-party JavaScript and first-party cookies are enabled. If first-party JavaScript is enabled, and the banner is visible, the rest of the page jumps up and down every so often. Under certain circumstances (not quite sure what they are, yet – a direct link to an answer, maybe? I'm seeing it ) the entire page jumps up and down a line every few seconds even when the banner is off-screen. The cookie banner keeps coming back unless both third-party JavaScript are enabled (and is solved). The cookie box occludes the “Learn more about Teams” link in the banner (with default Firefox window sizes) and the Job / Teams link in the sidebar. As it stands, – a site for hobbyists and researchers, whose audience is not very likely to purchase Teams – is much, much harder to use, for no benefit that I can see. Can you roll back this change, please?", "What is `$?` ? Is it a variable? The question is pretty straight forward. I can get the exit code of the previous command by using $?. But what exactly is it? I don't think it is a variable, because you can't have any special characters in the name of variable other than _. foo?foo=10 will result in the error: foo?foo=10: command not found So if it is not a variable, what is it? Are there others like it?", "White space below footer", "How to set default style for arrow tips in TikZ?", "Is there any way to see the custom messages/remarks of resolved/expired bounties?", "Outlook: scheduling recurring out-of-office? In Outlook, is there a way (or an add-on that can do it) to schedule a recurring out-of-office message? I work 4 10's, so I'm out of the office every Monday, and it's a bit of a pain to have to reset my out-of-office message every single week.", "I try to color the page numbers of my table of contents. I'm using the package hyperref along with the options : \\hypersetup{ colorlinks, linkcolor=wine-stain % custom color } Here's the output : The numbers remain black.. What should I do so the numbers become the same color as defined for the sections ? I tried to \\color{wine-stain}{\\tableofcontents} but still that doesn't work since \"Contents\" is also colorized and the subsection numbers are remaining black.", "It is true that $P(X&gt;t+s|X&gt;t)=P(X&gt;s)$ for certain values $t$ and $s$. However, how can I show that this still holds if: $T$ is a continuous random variable. That is $P(X&gt;T+s|X&gt;T)=P(X&gt;s)$ Both $T$ and $S$ are continuous RVs: $P(X&gt;T+S|X&gt;T)=P(X&gt;S)$ All the random variables are independent." ]

[ "How can install Desktop Toggl on Ubuntu 13.04? I try type: sudo add-apt-repository ppa:official-toggl/ppa sudo apt-get update sudo apt-get install desktop-Toggl But getting information desktop-Toggl not found.", "Many of the UK visa refusals we see here share a common pattern and the prevailing reasons refer to V 4.2 (a) and (c). I do understand that, while the applicants may describe very different individual circumstances, there's a consistent pattern and, broadly, fall into specific categories: Credibility (lifestyle, lack of ties, visit history, lies &amp; omissions) Funding (insufficient funds, provenance of funds, funds parking) Sponsorship (family, friends, employer) Question: What most commonly triggers a UK visa refusal where V 4.2 (a) and (c) are given as the grounds? Secondarily: Given that there is a clear pattern, to what extent are these refusals predictable? Does sponsorship make a difference? Is there a set of personal circumstances, however abstract, where a refusal is all but guaranteed? For example, why do those we see here on TSE who sought entry for the PLAB or British Army appear to be refused with a common theme? Is there a uniform shortcoming or is it just discrimination? PLAB: What is about applications for a visa, for the purpose of sitting the Professional and Linguistic Assessments Board (PLAB) exam, that seem to invite refusals. After all, the test is given so that international medical graduates can show that they qualify to practise medicine in the UK. The first part, PLAB 1, can be taken in centres outside of the UK. However, PLAB 2 can be taken only in the UK. Why can't you can't get a visa just to sit the exam, promising that you'll leave immediately after? British Army: Since Commonwealth citizens are eligible to apply online to join, even those who don't reside in the UK, why is it so difficult to get a visa just to attend an interview to see whether you are suitable? Even with an invitation from the Army, such visa applications seem to be unsuccessful. Isn't a career in the British Army a valid reason? Lastly: After such a refusal, what approaches would increase the chance of a successful application?", "I have removed the mentioned libraries. Then my system disconnected from NIS service and many packages are being removed. The problem is I am not even able to login in my system. When i restarted it is showing \"low graphics mode error\". I do not know what to do Please help me. I am a beginner to Ubuntu.", "$\\int_0^{\\infty} f(x)dx$ converges and $\\lim_{x\\rightarrow \\infty} f(x)$ exists, then $\\lim_{x\\rightarrow \\infty} f(x)=0$?", "Badge Notification Repeats Not sure if someone else has already raised this - I've got eleven notifications that I've received a Caucus badge on English Language Learners. Perhaps one notification for each community that I'm a member of? I am a member of the community, and did visit the election. Also, the badge hasn't been awarded more that once (so I think it's just the notification that's at fault). Note that this seems to happen for other badges, it has been reported for: Caucus, Nice Answer, Enthusiast.", "App Store on Mojave: \"We could not complete your purchase. cancelled\" Whenever I try to Get then Install any app from the App Store, I get this message: We could not complete your purchase. cancelled I did some searching online, but barely found any useful hits. What is this about?!", "Mechanism of Screenshot Basically I with my team are figuring out a way to block screenshots taken on our corporation's computers (Mac mostly). I have searched it extensively and found that there is something called Screen buffer which is being accessed by any screenshot taking software (eg. Snipping Tool etc). I tried to find the exact mechanism and the actual implementation of such softwares but with no luck. Also I found out that Netflix uses some kind of technology which corrupts screenshot image and blackens it. I did not find any actual mechanism or implementation to study it further. I also came across something called Hardware overlays but did not understand it properly in order to use it for actual implementation. I have considered a way to edit scancode maps in registry but I am looking for a more general way. I read a few articles for apple's FPS though. Can somebody please guide me through this? Some good resources for the same would be highly appreciated. Any particular or relevant forums or subs to discuss this are also welcome", "Determine if a set of tiles on a grid forms an enclosed shape", "No space left on device -- but there is space I'm running an Ubuntu 12.04.1 server in a VMware virtualized environment that has a strange issue. Twice now, at seemingly random times, the machine has suddenly been unable to write to the root partition despite plenty of space seemingly available. I'm at a loss trying to figure out what's wrong. \"df -h\" shows all mounted volumes with 40% or more free space. Both times this has happened, rebooting resolved it for a few minutes, and then it was back to saying \"no space left on device.\" Restoring it from a snapshot seems to fix it for longer, but since this has now happened again, I'm not sure what to do with it. If it helps, the machine is a network print server running CUPS 1.5.3 and Samba 3.6.3.", "poll() failed, context incorrect? - Example: bpy.ops.view3d.background_image_add() I keep on getting context errors in the Blender Python API. I don't understand the issue of the context in the API, how do I know which is the correct context? Thanks!", "How does the Doctor know how old he is? I've often wondered, how does the Doctor know how old he is? He not only travels through time, but also through space, and visits planets where days can be shorter or longer than 24 hours. How does he 'keep score'? Also, does he count his age in Earth years or Gallifrey years? They might be completely different in length.", "jQuery: Check if image exists", "`--no-install-recommends` only specified packages I want to install xfce4-goodies but I don't want Midori Browser. With --no-install-recommends I don't know how to specify only Midori. I want the rest of packages. How to do that? Thanks!", "From the on the dual of a norm: $X$ and $Y$ are normed spaces, and we associate with each $f\\in L(X,Y)$ (the space of bounded linear operators from $X$ to $Y$) the number $$\\|f\\| = \\sup\\{|f(x)|:x\\in X, \\|x\\| \\leq 1\\}.$$ At some point in the proof that $L(X,Y)$ is bounded, it seems like they use the inequality $$\\|fx\\| \\leq \\|f\\|\\cdot\\|x\\|,$$ where $\\|x\\|\\leq 1$. I can't see why this should holds. $\\|f|\\|$ is the supremum of what $|f(x)|$ can be, given that $\\|x\\|\\leq 1$. So, given that $\\|x\\| \\leq 1$, $|fx|$ should be bounded by $\\|f\\|$. But why should it be bounded by $\\|f\\|\\cdot\\|x\\|$?", "Stopping Dwarf Fortress from auto-pausing Is it possible to prevent DF from pausing every time something comes up (liking hitting gold or whatever). The reason is that I am doing extensive mining and I want to leave the process unattended till it is over.", "What is the error \"Every derived table must have its own alias\" in MySQL?", "What's the difference between the work function and ionisation energy?", "There are 11 letters in the word. M - 1 I - 4 S - 4 P - 2 so the number of different permutations is $\\dfrac{11!}{1! 4 !4!2!}$ Is this correct solution?", "Decrypt all RSA ciphertexts if you can break 1% of them", "Possible Duplicate: The FAQ specifies that: Use your downvotes whenever you encounter an egregiously sloppy, no-effort-expended post, or an answer that is clearly and perhaps dangerously incorrect. But if I find a correct question, closed (or not yet) as duplicate, is downvote a correct behavior for Stack&nbsp;Overflow policy?" ]

[ "How to create polygons with straight lines and right angles in QGIS? When creating a polygon, how do I do it so that the lines are straight (90, 0 degrees, etc.) and when I create corners they can be right angles? For instance, how do I create a perfect square or rectangle?", "Inconsistent line spacing", "Add transparency to an existing PNG I'd like to use this image on a web site. What I need to do is change the background from black to transparent, so I can use the arrow on my site maintaining the page background. I used Gimp to convert the image to .png, but how do I proceed now?", "PC Blue Screens and then instantly reboots. How do I stop this or find the error later?", "Deleting comments and review actions cause layout to be broken, AJAX response contains full page", "Are objects in PHP passed by value or reference?", "Disabling Intel Turbo Boost in ubuntu", "Why don't files from Xbox 360 show up when USB drive is plugged into computer?", "How should I structure my URLs for both SEO and localization?", "What is the function of the RNA primer in DNA replication?", "Does priority matter in Magic?", "Aufbau principle in modern quantum theory", "To show that either $R$ is a field or $R$ is a finite ring with prime number of elements and $ab = 0$ for all $a,b \\in R$.", "$\\displaystyle\\int_0^0\\frac 1x\\:dx$ This integral is defined ? If it define, what is the value ? Please,step by step", "Compute $\\iint\\limits_R\\frac{y}{x+y^2}dA$ where $R=[0,1]\\times[1,2]$ Compute $\\displaystyle\\iint\\limits_R\\frac{y}{x+y^2}dA$ where $R=[0,1]\\times[1,2]$ $\\displaystyle\\int_0^1\\int_1^2\\frac{y}{x+y^2}dydx=\\int_0^1\\int_1^2y(x+y^2)^{-1}dydx$ How do I integrate the denominator if the superscript is $-1$? Hints are appreciated!", "What IDE to use for Python?", "In his first lesson (transcripted in \"Tips on Physics\"), Feynman talks about math for physicists in a very cool and practical way. And at the end of the section he talks something like \"so the first thing to do is to learn to learn derivative, integral and algebra\" (I don't know how much precise I'm being because I've read it in Portuguese). I would to know if there is some book that deals with math as Feynman did it in this lesson (respecting formalities, but teaching how to use the practical rules)? Also, someone have any recommendations for algebra book (college level)?", "Prove by induction. How do I prove $\\sum\\limits_{i=0}^n2^i=2^{n+1}-1$ with induction? $\\displaystyle\\sum_{i=0}^n2^i=2^{n+1}-1$. I don't understand induction so I could use some help.", "Comprehensive list of activation functions in neural networks with pros/cons Are there any reference document(s) that give a comprehensive list of activation functions in neural networks along with their pros/cons (and ideally some pointers to publications where they were successful or not so successful)?", "Hotspot and Internet access together — why not? If I try to set up a hotspot in GNOME, I get the following message: If you have a connection to the Internet other than wireless, you can use it to share your internet connection with others. Switching on the wireless hotspot will disconnect you from &lt;network name&gt;. It is not possible to access the internet through your wireless while the hotspot is active. What are the technical reasons why I can't set up an Hotspot and be connected to the Internet at the same time?" ]

[ "Do I need to tame my twitchy F5 finger? I just got this error message for the first time (I was getting this as the response to any request on the SE network for about the last five minutes, until now): We're sorry... There are an unusual number of requests coming from this IP address. To protect our users, we can't process any more requests from this IP address right now. We'll restore access as quickly as possible, so try again soon. If you believe you have reached this page in error, contact us. As far as I know, I was not spamming SE or participating in DOS attack, and I find it unlikely that any of my office coworkers who share my IP address were doing so either. Granted, I was pressing F5 a lot. But I've always pressed F5 a lot on SE, and have never gotten this message before. So my question is: Is it possible to get this error message simply by refreshing too much or too often? Or is that message reserved for a truly massive number of requests that are unlikely to be caused by one person refreshing a lot? (In the former case, I can't explain why I've never gotten it before; in the latter case, I can't explain why I just got it now).", "How to change charset of my website to utf8?", "How can I get an email message's text content using Python?", "How can Zeno's dichotomy paradox be disproved using mathematics? A brief description of the paradox taken from : Suppose Sam wants to catch a stationary bus. Before he can get there, he must get halfway there. Before he can get halfway there, he must get a quarter of the way there. Before traveling a quarter, he must travel one-eighth; before an eighth, one-sixteenth; and so on. This description requires one to complete an infinite number of tasks, which Zeno maintains is an impossibility. This sequence also presents a second problem in that it contains no first distance to run, for any possible (finite) first distance could be divided in half, and hence would not be first after all. Hence, the trip cannot even begin. The paradoxical conclusion then would be that travel over any finite distance can neither be completed nor begun, and so all motion must be an illusion. How can this be disproved using math, as obviously we can all move a walk from one place to another?", "Web applications that want to force a resource to be downloaded rather than directly rendered in a Web browser issue a Content-Disposition header in the HTTP response of the form: Content-Disposition: attachment; filename=FILENAME The filename parameter can be used to suggest a name for the file into which the resource is downloaded by the browser. (Content-Disposition), however, states in (The Filename Parameter) that the file name can only use US-ASCII characters: Current [RFC 2045] grammar restricts parameter values (and hence Content-Disposition filenames) to US-ASCII. We recognize the great desirability of allowing arbitrary character sets in filenames, but it is beyond the scope of this document to define the necessary mechanisms. There is empirical evidence, nevertheless, that most popular Web browsers today seem to permit non-US-ASCII characters yet (for the lack of a standard) disagree on the encoding scheme and character set specification of the file name. Question is then, what are the various schemes and encodings employed by the popular browsers if the file name “naïvefile” (without quotes and where the third letter is U+00EF) needed to be encoded into the Content-Disposition header? For the purpose of this question, popular browsers being: Firefox Internet Explorer Safari Google Chrome Opera", "Let $p,q$ be primes, $p≠q$, then I have to show that $\\mathbb{Q}(\\sqrt{p},\\sqrt[3]{q})= \\mathbb{Q}(\\sqrt{p}\\cdot \\sqrt[3]{q})$ So far I've tried a lot of things with minimal polynomials and bases, but I'm far from any argument that I find sufficient. This is an example from my algebra course, first chapter about field extension. So far we know about basic definitions, minimal polynomials and their properties, algebraic elements and algebraic fields. Could someone maybe give me a hint about how to proceed? Thanks a lot!!!", "For all square matrices $A$ and $B$ of the same size, it is true that $(A+B)^2 = A^2 + 2AB + B^2$? The below statement is a true/false exercise. Statement: For all square matrices A and B of the same size, it is true that $(A + B)2 = A^2 + 2AB + B^2$. My thought process: Since it is not a proof, I figure I can show by example and come to a valid conclusion based on such example. My work: Come up with a square matrix A and B let both be a 2 by 2 matrix(rows and cols must be same). Matrix $A$: $A = \\begin{array}{ccc} 3 &amp; 5 \\\\ 4 &amp; 6 \\\\ \\end{array} $ Matrix $B$: $B = \\begin{array}{ccc} 5 &amp; 8 \\\\ 9 &amp; 4 \\\\ \\end{array} $ $A + B = \\begin{array}{ccc} 8 &amp; 13 \\\\ 13 &amp; 10 \\\\ \\end{array}$ $(A + B)^2 = \\begin{array}{ccc} 233 &amp; 234 \\\\ 234 &amp; 264 \\\\ \\end{array}$ $A^2 = \\begin{array}{ccc} 29 &amp; 45 \\\\ 36 &amp; 56 \\\\ \\end{array}$ $(AB) = \\begin{array}{ccc} 60 &amp; 44 \\\\ 74 &amp; 56 \\\\ \\end{array}$ $2(AB) = \\begin{array}{ccc} 120 &amp; 88 \\\\ 234 &amp; 112 \\\\ \\end{array}$ $B^2 = \\begin{array}{ccc} 97 &amp; 72 \\\\ 81 &amp; 88 \\\\ \\end{array}$ $A^2 + 2AB + B^2 = \\begin{array}{ccc} 246 &amp; 205 \\\\ 265 &amp; 256 \\\\ \\end{array}$ Based my above work, the answer is false. Is there another way to approach the problem? It seems like a lot of work needed to be done for a true/false question which raised my suspicion about whether there is a better way to look at the problem.", "How to download Ubuntu over an unreliable connection", "Who was the piano player that Starbuck met in the bar on Galactica? Towards the end of season four, Starbuck meets a piano player in the makeshift bar on Galactica. Now, it appears that this guy is some kind of ghost/angel like Caprica-6 and the ghost Baltar - but I have an idea that he could also be the original copy of the seventh model (Daniel). It's mentioned right in the episode before that Cavil poisoned all of the bodies that were being prepared to accept a copy of Daniel - but it's ambiguous about the fate of the original cylon with that personality. Daniel was also mentioned as an 'artist' and 'sensitive' person. So - could it have been Daniel that helped Starbuck realise what the music meant?", "Correct XML serialization and deserialization of \"mixed\" types in .NET", "vi shows as vim When I type vi into a terminal it shows the following display: Note that it says vim not vi, I'm sure I haven't downloaded vim yet and that this is actually vi not vim: for example the arrow keys print ABCD instead of moving.", "How can I align a multiple-line footnote text right to the footnote mark? How can I have the following \"footnote layout\"? Some Text Some Text Some Text Some Text² Some Text 2 FOOTNOTETEXT FOOTNOTETEXT FOOTNOTETEXT FOOTNOTETEXT FOOTNOTETEXT FOOTNOTETEXT FOOTNOTETEXT FOOTNOTETEXT FOOTNOTETEXT FOOTNOTETEXT My problem is that the footnote text starting with the second line is too far left. \\documentclass{article} \\usepackage{blindtext} \\begin{document} \\blindtext\\footnote{\\blindtext} \\end{document}", "Getting the array length of a 2D array in Java", "How to model an entity type that can have different sets of attributes?", "Maybe the underlying question is what the Voltage-Current curve looks like. Can I drive it from a voltage source (like you drive a heater) or from a current source (like you drive an LED)? Or even different than those two options? ADDITIONAL1: Say (hypothetically) I have two commercially available identical Peltier's, they are spec'd 6V/3A. Can I connect these in series to a 12Vdc power supply without any worries? CONCLUSION1: Current/Voltage load curve is reasonably linear, both driving from current or voltage source will do fine as long as the device is operated within its spec. (Olin Lathrop, Russell McMahon) CONCLUSION2: Don't drive a Peltier from PWM, power loss due to current increase, grows more rapidly than cooling power. (Olin Lathrop) CONCLUSION3: Beware the mechanical wear of the device with continues cycling. Eg. don't use a thermostat on/off controller. (Russell McMahon)", "Remove border of top left table cell", "Prove that you can make change for any amount greater than 7 cents using only 3 and 5 cent coins. I am pretty sure this question has something to do with the Least Common Multiple. I was thinking that the proof was that every number either is or isn't a multiple of $3, 5$, and $8\\left(3 + 5\\right)$. If it isn't a multiple of $3,5$, or $8$, great. You have nothing to prove. But if it is divisible by one of them, I couldn't find a general proof that showed that it wouldn't be divisible by another one. Say $15$, it is divisible by $3$ and $5$, but not $8$.", "Where can I find other RPG players?", "Where can I ask questions for website recommendations? Is there any Stack Exchange site where I can ask others to recommend me good web sites for solving specific problems? For example I would like to know if there is any URL shortening website that can allow me to define the url. For example instead of http://bit.ly/1gX2dD0 I would like it to be http://bit.ly/superflow - if \"superflow\" is not available then I will invent another word. I can imagine that such services are paid but I don't need the link to last more than one day, and maybe there is such a website.", "I want to be able to tell if the mains voltage is on or off with an Arduino. How could I do this safely with minimal components (or components from Radio Shack)?" ]

[ "Failed to allocate memory: 8", "What do I need in a camera to take non-blurry photos of a fast-moving child?", "How to create my own math operator with limits? How can i write my own math operator with limits? I want it to look like: \\sum\\limits_{e=1}^{m} but with a capital A (if possible bigger than the normal text) instead of the sum. Thanks for the help!", "Many To Many Relationships I am working on a conceptual model for a database. I have the following entities: Student (id, name, date of birth, department) Subject (id, name) This is a many-to-many relationship, one student may be enrolled in many courses, each course has many students. From what I understand, as I should break this many-to-many relationship by introducing a new into a entity, say 'registered' which allows a one-to-one relationship or one-to-many relationship? Is this correct design decision?", "If I've decided to update my SE avatar (in any of the various ways well described in the answer to this ), am I able to return to either the original stock image or previous avatar images I have used?", "Why couldn't Bond have backup at the battle of Skyfall? I think I am missing a key plot point here. Bond had to fake-kidnap M and bring her to Skyfall in order to lure Silva there for one last stand. Why did this have to be a secret from his colleagues at MI6? Why couldn't there have been other agents there to help defend the house and take down Silva? Also, why did he have to have Q lay a fake trail to get Silva to follow him to Skyfall when he was actually going there, and he wanted Silva to follow him?", "How to prove $B-A \\succeq 0 \\Leftrightarrow$ ellipsoid $x^TBx \\leq 1$ contains $x^TAx \\leq 1$? Assume $A \\in \\textbf{S}^n_{++}$, an ellipsoid centered at the origin given by $$\\mathcal{E}_A = \\{x\\mid x^TA^{-1}x \\leq 1\\}$$ Then we have $\\mathcal{E}_A \\subseteq \\mathcal{E}_B $ if and only if $B-A \\succeq 0$. This is the proposition in the Boyd &amp; Vandenberghe's (pages 45-46). The authors gave only the result, without proof. How to prove it?", "How to scale a tikzpicture including texts? It seems that the scale option scales only the length of lines, but not the size of texts. For instance, 1 and true and not scaled in the following code. \\begin{tikzpicture}[thick, scale=0.6] \\draw [dashed] (1,12) -- (11,12); \\node[above] at (4,11) {1}; \\node[above] at (8,11) {true}; \\end{tikzpicture} Could anyone tell me how to scale everything together within a tikzpicture? Thank you very much! PS: It is a picture in a presentation with Beamer.", "table of contents: adding a vertical space In a table of contents that has been generated with LaTeX's \\tableofcontents command, I would like to add a vertical space before a Chapter item in the table of contents. One way that I have in my notes is to use \\addtocontents{toc}{\\protect\\vspace{10pt}} at a desired location in the document so that this gets processed by \\tableofcontents to include an appropriate vertical space in the table of contents. I have two questions: Is the above the correct way to get a vertical space in a table of contents? Why is it necessary to use the \\protect command here? Thank you...", "About the term $-\\nabla_{[u,v]}w$ in the definition of Riemann curvature tensor", "HTTP GET request in JavaScript? I need to do an request in JavaScript. What's the best way to do that? I need to do this in a Mac OS X dashcode widget.", "I'm trying to delete some old flow which are inactive via workbench. DestructiveChanges.xml &lt;?xml version=&quot;1.0&quot; encoding=&quot;UTF-8&quot;?&gt; &lt;Package xmlns=&quot;http://soap.sforce.com/2006/04/metadata&quot;&gt; &lt;types&gt; &lt;members&gt;Advanced_Round_Robin&lt;/members&gt; &lt;name&gt;Flow&lt;/name&gt; &lt;/types&gt;Ï &lt;/Package&gt; package.xml &lt;?xml version=&quot;1.0&quot; encoding=&quot;UTF-8&quot;?&gt; &lt;Package xmlns=&quot;http://soap.sforce.com/2006/04/metadata&quot;&gt; &lt;version&gt;48.0&lt;/version&gt; &lt;/Package&gt; I've added both file in zip and in workbench when I deploy using this zip file I get below error. insufficient access rights on cross-reference id What permission I need to have to perform this action? Also is there way I can delete few version of same flow only? Like keep only last 3-4 version and delete all previous version of given flow? Thank you.", "Efficiently replace all accented characters in a string? For a poor man's implementation of near-collation-correct sorting on the client side I need a JavaScript function that does efficient single character replacement in a string. Here is what I mean (note that this applies to German text, other languages sort differently): native sorting gets it wrong: a b c o u z ä ö ü collation-correct would be: a ä b c o ö u ü z Basically, I need all occurrences of &quot;ä&quot; of a given string replaced with &quot;a&quot; (and so on). This way the result of native sorting would be very close to what a user would expect (or what a database would return). Other languages have facilities to do just that: , in , , . But what about JavaScript? Here is what I have right now. // s would be a rather short string (something like // 200 characters at max, most of the time much less) function makeSortString(s) { var translate = { &quot;ä&quot;: &quot;a&quot;, &quot;ö&quot;: &quot;o&quot;, &quot;ü&quot;: &quot;u&quot;, &quot;Ä&quot;: &quot;A&quot;, &quot;Ö&quot;: &quot;O&quot;, &quot;Ü&quot;: &quot;U&quot; // probably more to come }; var translate_re = /[öäüÖÄÜ]/g; return ( s.replace(translate_re, function(match) { return translate[match]; }) ); } For starters, I don't like the fact that the regex is rebuilt every time I call the function. I guess a closure can help in this regard, but I don't seem to get the hang of it for some reason. Can someone think of something more efficient? Answers below fall in two categories: String replacement functions of varying degrees of completeness and efficiency (what I was originally asking about) A of , which is now among JS engines (not so much at the time of the question) and could solve this category of problem much more elegantly.", "How would you evaluate $\\liminf\\limits_{n\\to\\infty} \\ n \\,|\\mathopen{}\\sin n|$ How would you evaluate the limit inferior of the sequence $n\\,|\\mathopen{}\\sin n|$? That is, $$\\liminf\\limits_{n\\to\\infty} \\ n \\,|\\mathopen{}\\sin n|$$ Edit. Let $\\mu$ be the irrationality measure of $\\pi$. Since $\\mu$ is not known, I will split the question: Assuming $\\mu &gt; 2$, what is $\\liminf\\limits_{n\\to\\infty} \\ n\\,|\\mathopen{}\\sin n|$? Assuming $\\mu = 2$, what is $\\liminf\\limits_{n\\to\\infty} \\ n\\,|\\mathopen{}\\sin n|$? I kind of like its graph...", "Is there any easy way on Windows to log %CPU time per process over time to a file for later analysis? As far as I can see... Task manager shows me the %CPU per process but only visually - no way to save to a file. Perfmon will let me save to a file, and will additionally create a time-based file (taking snapshots at specified time intervals) - which is almost what I want, except that as far as I can see it can't break down the %CPU by process. Process Explorer will let me break down by process, but it will only save the file as a snapshot of a single point in time So, none of these are quite what I need: I need to get a file that contains something like 'top 10 processes by CPU, every 15 seconds, until I stop the monitoring' The reason I need this because I have a machine on which some process is causing occasional brief spikes in CPU usage several times a day and I need to find out which process is the culprit. Can anything do that, or have I missed some feature of perfmon or process explorer?", "Why (and how) did using cat on binary files mess up the terminal? If I understand the cat manual correctly: concatenate files and print on the standard output cat will take files as argument and print them on standard output. What I don't get is if I use the command: cat img.png &gt; copy.png I will obtain 2 png files identical while if I just cat img.png I have all chance that my terminal get messed up and misinterpret what I type. How's that possible? Binary values are still binary data. Why it does not simply shows a series of 0 and 1 or the interpretation of those binary data in ASCII or whatever the encoding in terminal is? Is this behavior also possible by cating a text file containing strange characters? Should a mechanism to prevent this behavior like try{}catch{} statement should be implemented?", "This is probably pretty basic, but to save me an hour or so of grief can anyone tell me how you can work out the number of bits required to represent a given positive integer in Java? e.g. I get a decimal 11, (1011). I need to get the answer, 4. I figured if I could work out how to set all the bits other than the most significant bit to 0, and then >>> it, I'd get my answer. But... I can't.", "We have been using Notes and Attachment to store files related to the record. I also read about Files in salesforce. How are Files different from Attachment? Are there any limitations or benefits of using Files instead of Attachments? Are Files available for all editions of Salesforce? Is it possible to link Files to particular records so they are visible as related list? I tried looking into the content version but cant seem to find anything to relate to a record", "How could I write my name, for example, to look like the \\LaTeX logo? How could I write my name, for example, in a \\LaTeX style? It is just interesting, as in Google all other things pop up when I try to search for an answer!", "Unable to install VLC This is what happens: sudo apt-get install vlc Reading package lists... Done Building dependency tree Reading state information... Done E: Unable to locate package vlc Please help. I would also like to know when this error occurs, I've seen it before too." ]

[ "how many conditional sentence types are possible? I wonder how many conditional sentence types are possible. Basically, there are four main and two mixed types. By mixing tenses, it could be up to nine of them. Are the rest viable? I came across the following examples in Full Spate Pre-Profficiency Primer: After you have just sold alcohol to a young guy. If he is if under eighteen, you should not have sold him the alcohol. If he promised to bring the drinks, he will. If you will take a seat, the doctor will see you shortly. (Likely, the former will demonstrates politeness only.) I would be grateful if you would tell me a little about your friends. (The same politeness, but would instead.) If he will keep eating all those biscuits, he can not expect to stay as slim as he used to be. I would be grateful if someone could shed more light on the topic.", "Suppose $n$ is a non negative integer $\\geq 4$ and $\\sigma\\in S_n$ a permutation. Conjugacy classes in $S_n$ are completley determined by the cycle structure of $\\sigma$. If we let the alternating group $A_n$.act on $S_n$ by conjugation, the orbits coincide with the conjugacy classes in $S_n$ except for those (even) permutations whose cycle structure is composed of even cycles (which corresponds to cycles of uneven length) of distinct order (fixed points are treated as cycles of length $1$.) See For instance a $3$-cycle in $A_4$ has cycle structure $[3,1]$ which fits the bill, and a $5$-cycle in $A_5$ or $A_6$ works too, since the cycle structure is $[5]$ and $[5,1]$ respectively. On the other hand, a $3$-cycle in $A_5$ will does not satisfy the criteria as it has cycle structure $[3,1,1]$ with two fixed points. In this case, the conjugacy class of $\\sigma$ inside $S_n$ splits in $2$ orbits of the conjugation action of $A_n$, and if $\\tau$ is any odd permutation, for instance $(12)$, then we have $$\\mathrm{Conj}_{S_n}(\\sigma)=\\mathcal{O}(\\sigma)\\coprod\\mathcal{O}(\\tau\\sigma\\tau^{-1})$$ My question is How can we differentiate between the two orbits? Does it have geometric meaning? I can see that this information can be useful when looking at representations of the alternating groups, since there are as many irreducible representations as conjugacy classes. As for some geometric interpretation, I ask because there is one for the three cycles in $A_4$. If $S_4$ is understood as the group of symmetries of a regular tetrahedron, then $A_4$ is the subgroup of direct symmetries, and a $3$-cycle corresponds to a rotation of angle $\\frac{2\\pi}{3}$ or $\\frac{4\\pi}{3}$ with axis passing through one of the vertices. Conjugacy classes inside $A_n$ preserve the angle, and that's how we can tell them apart. In this case the computations are so simple we don't really need this picture, but I think it is a nice way to understand the fact $3$-cycles in are not all conjugate inside $A_4$...", "Let us denote by $\\chi(G)$ the chromatic number, which is the smallest number of colours needed to colour the graph $G$ with $n$ vertices. Let $\\bar{G}$ be the complement of $G$. Show that (a) $\\chi(G)+\\chi(\\bar{G}) \\leq n+1$ (b) $\\chi(G)\\chi(\\bar{G}) \\geq n$ I was able to prove (a) using induction. Any hints on proving (b)?", "Calculating values of field based on two others using Field Calculator in ArcGIS Desktop? I need to combine two fields in an attribute table. I want to do this using the field calculator. What is the proper script to write to combine a field called \"name\" and \"type\", so that it produces one field with \"name type\"? I'm using ArcGIS Desktop 10.0.", "Prove $x \\equiv a \\pmod{p}$ and $x \\equiv a \\pmod{q}$ then $x \\equiv a\\pmod{pq}$ Prove $x \\equiv a \\pmod{p}$ and $x \\equiv a \\pmod{q}$ then $x \\equiv a\\pmod{pq}$ for $p\\neq q$ distinct primes. Where can I start with this proof? It looks similar to the Chinese Remainder Theorem, but that deals with two different a values.", "Does anyone know of a .NET date/time parser similar to (handles stuff like \"tomorrow\" or \"3pm next thursday\")? Note: I do write Ruby (which is how I know about Chronic) but this project must use .NET.", "Does a Readied spell immediately use a spell slot?", "When to use Stateful session bean over Stateless session bean?", "Show tabs in Chrome full screen mode? Firefox can do it, can Chrome? Here's what I'm looking for:", "Show that $(p \\to q) \\lor (q \\to p)$ is a tautology I tried to prove that $(p \\to q) \\lor (q \\to p)$ is a tautology. I used $p$ and $¬q$ as conditions. (Premises 1 and 5) I managed to get to a solution, but I'm not sure if it's right. Can you please check it? Thank you!!!:)", "Covariance of Poisson and Conditional Binomial RV's Problem Statement Let $X$ and $Y$ be random variables such that $X \\sim \\text{Poisson}(\\lambda)$ and $Y|X \\sim \\text{Binomial}(x+1,p)$. Find $\\text{Cov(X,Y)}$. Attempt at a Solution I would like to be able to write $Y$ as $X + Z$ where $Z$ is Poisson and independent of $X$, since then by the variance is easy to compute. To this end, write $Y|X$ as a sum of independent binomials: $ Y|X = Z_1|X + Z_2|X, $ where $Z_1|X \\sim \\text{Binomial}(1,p)=\\text{Bernoulli}(p)$ and $Z_2 | X \\sim \\text{Binomial}(x,p).$ Then $Z_2 \\sim \\text{Poisson}(\\lambda p)$, which we can obtain by directly computing the pdf: \\begin{aligned} P(Z_2 = z) &amp;= \\sum_x P(Z_2=z, X=x)\\\\ &amp;= \\sum_x P(Z_2=z\\mid X=x)P(X=x) \\\\ &amp;= \\sum_{x=y}^\\infty \\frac{e^{-\\lambda} \\lambda^x}{x!}\\frac{x!}{z!(x-z)!}p^z(1-p)^{x-z} \\\\ &amp;= \\frac{(\\lambda p)^z}{z!}e^{-\\lambda p} \\sum_{x=z}^\\infty \\frac{[\\lambda(1-p)]^{x-z} e^{-\\lambda(1-p)}}{(x-z)!} \\\\ &amp;= \\frac{(\\lambda p)^z}{z!}e^{-\\lambda p}. \\end{aligned} However, I cannot get the same approach to simplify for $Z_1|X$, which instead involves the CDF of $X$. I also tried this approach on $Y|X$ directly, hoping to obtain a sum in the form of the expectation of $X$, but I can't seem to reduce it. Even if I could, I'd still need to compute $E[XY]$ for the covariance. I suspect there may be a better approach than grinding through several more sums.", "14 months ago, an supplement was published that discussed how the ranger described in the Player's Handbook was under powered. These rules reimagined the ranger's abilities, and suggested that an official version would be released later. Finally, we come to implementation. If this iteration of the ranger, or a future revision of it, grades high enough, our plan is to present it as a revised ranger in a future D&amp;D sourcebook. Does that Sourcebook exist yet? If not, have the devs given an update or told us their intentions?", "Is a clean install better than upgrading? Is it better to install Ubuntu completely new or is the upgrade process just as good? In other words, will my computer run just as problem-free and efficiently when I upgrade as opposed to a fresh install?", "Suppose that $f$ is differentiable on $\\mathbb{R}$ and $\\lim_{x\\to \\infty}f'(x)=M$. Show that $\\lim_{x\\to \\infty}f(x+1)-f(x)$ exists and find it. I've been stuck on this question for a long time now and was wondering if anyone could show me how it's done. So far I have done the following: Since $\\lim_{x\\to \\infty}f'(x)=M$ then $\\forall \\epsilon ,\\exists A &gt;0$ s.t. if $x&gt;A$ then $|f'(x)-M|&lt;\\epsilon$. So we have that $M-\\epsilon&lt;f'(x)&lt;M+\\epsilon$. By MVT on $[x,x+1]$ for $x&gt;A$, $\\exists c\\in (x,x+1)$ s.t. ${f(x+1)-f(x)\\over 1}=f'(c)$. Therefore, $M-\\epsilon&lt;f(x+1)-f(x)&lt;M+\\epsilon$. However, I do not know what to do after this.", "I know that there is a simple way to shutdown the computer in command prompt, but is it possible to do system updates and then shutdown the computer in command prompt? For example, when Vista needs to install updates, it will let me install them and shut down by clicking the Shut Down button (while relegating the normal shut down button into the menu). So is there a command to do this in command prompt?", "Do we have more history for cd?", "Evaluate $\\lim_{y\\to 0} \\dfrac {(x+y)\\sec (x+y) - x\\sec x}{y}$ Evaluate $\\lim_{y\\to 0} \\dfrac {(x+y)\\sec (x+y) - x\\sec x}{y}$. My Attempt: $$=\\lim_{y\\to 0} \\dfrac {(x+y) \\sec (x+y) - x\\sec x}{y}$$ $$=\\lim_{y\\to 0} \\dfrac {x\\sec (x+y) + y\\sec (x+y) - x\\sec x}{y}$$ $$=\\lim_{y\\to 0} \\dfrac {x(\\sec (x+y) - \\sec x) + y\\sec (x+y)}{y}$$", "Wubi with 14.10 doesn't work - failed to partition the selected disk I tried to install Ubuntu 14.10 on my computer with Wubi. The installation appeared to work in Windows, and told me to reboot. After rebooting the Ubuntu installer continued the installation, until it stopped with an error message: Failed to partition the selected disk with the detail This probably happened because are too many primary partitions in the partition table.", "If we have a function $f:A \\rightarrow B$, then one way to give meaning, I think, to this function, in terms of set theory, is to say, that $f$ is actually a binary relation $f=(A,B,G_f)$, where $G_f \\subseteq A \\times B$ is the graph of the function. Now my question is: what is $f$ if $\\bullet \\ A=\\emptyset, \\ B\\neq\\emptyset$,? $ \\bullet \\ B=\\emptyset, \\ A\\neq\\emptyset$ ? $ \\bullet \\ B=\\emptyset, \\ A=\\emptyset$ ? (Another way to formulate this, I think, would be: How do the sets $\\emptyset\\times B,\\ A\\ \\times \\emptyset, \\ \\emptyset \\times \\emptyset $ look like? Are they all $\\emptyset$ ?)", "Why did Aragorn and Theoden ride out at the Hornburg? In the Battle of the Hornburg from The Two Towers, Aragorn and Theoden say \"We must ride out.\" Why did they do this? Was it just a matter of honor? Did they ride out on their horses in the middle of battle because they thought it was the end, as they were outnumbered? Was it because Aragorn knew Gandalf was coming so they were confident they were about to win?" ]

[ "Where is the \"Add vector layer\"-button in GRASS 6.4.4. plug-in QGIS 2.10.1? I've just downloaded and installed the new version of QGIS 2.10.1 with GRASS 6.4.4. When opening a new GRASS mapset and importing layers, I missed the button \"Add a new vector layer\". I've updated the GRASS plugin, but again the button wasn't there (all other GRASS symbols except \"add raster layer\" were visuable). It's maybe a stupid question of a GIS beginner, but what can I Do? Is there an option to add (not import) a vector layer via the GRASS toolbox?", "Prove if $|a_{n+1}|/|a_n| \\leq |b_{n+1}|/|{b_n}|$ and $\\sum |b_n|$ is convergent, then $\\sum |a_n|$ is convergent", "'Good' review audits can be misleading", "table of contents: adding a vertical space In a table of contents that has been generated with LaTeX's \\tableofcontents command, I would like to add a vertical space before a Chapter item in the table of contents. One way that I have in my notes is to use \\addtocontents{toc}{\\protect\\vspace{10pt}} at a desired location in the document so that this gets processed by \\tableofcontents to include an appropriate vertical space in the table of contents. I have two questions: Is the above the correct way to get a vertical space in a table of contents? Why is it necessary to use the \\protect command here? Thank you...", "The continuity of $f(x,y) = \\frac {\\sin (xy)} {\\sqrt {x^2 + y^2}}$ at $(0,0)$ I got a function: $f(x,y) = \\frac {\\sin (xy)} {\\sqrt {x^2 + y^2}}$ if $(x,y) \\not = (0,0)$, otherwise $f(x,y) = 0$, and I should look at its continuity in $(0,0)$ I tried the sandwich theorem but got slightly stuck unfortunately $ 0 \\le \\left|\\frac {\\sin (xy)} {\\sqrt {x^2 + y^2}}\\right| \\le 1$ I was thinking that $\\sin (xy)$ is a restricted function, but not sure what to with $\\sqrt {x^2 + y^2}$ if $x,y$ are too small so I think my idea doesn't work. Then it would look like: $ 0 \\le \\left| {\\sin (xy)} \\right| \\le \\sqrt {x^2 + y^2} = 0$ Any other idea please?", "What formula would you use to add up a column based on results from two drop down menus?", "Is every Lie subgroup of $SU(2)$ closed?", "How can I replace a string in a file(s)? Replacing strings in files based on certain search criteria is a very common task. How can I replace string foo with bar in all files in the current directory? do the same recursively for sub directories? replace only if the file name matches another string? replace only if the string is found in a certain context? replace if the string is on a certain line number? replace multiple strings with the same replacement replace multiple strings with different replacements", "What is Skynet's ultimate goal after defeating the resistance? Is it stated in any expanded universe what Skynet's plans were after wiping out the Human race (assuming that was its plan)? Maybe space travel to colonise different planets or something else entirely?", "ssh into an account which has no home directory", "I went through a , but the answer was informing how to hide the monitor, but not how to disable it. I do not want any new windows to creep into the laptop display when the external display is connected. I could not find any in the Display Settings (under System Preferences). I don't want to close the lid because I think it impacts the air flow of the MacBook Pro. I don't want to close the lid because the sound quality is reduced.", "Comparing values between two tables How to compare values between two different tables? I have two tables as shown below: Table 'A' sql_id OPERATION OPTIONS 63kf3an2j0pk SELECT STATEMENT 63kf3an2j0pkc TABLE ACCESS FULL Table 'B' sql_id OPERATION OPTIONS 63kf3an2j0pk SELECT STATEMENT 63kf3an2j0pkc INDEX UNIQUE SCAN IDX_THU I need to compare the values in Table 'A' and Table 'B' for the given sql_id. My question is how to find the changed values. In this case in Table 'A' the second line is TABLE ACCESS FULL. Table 'B' the the second line is INDEX UNIQUE SCAN IDX_THU. So here the value has changed. How can I find that using query? Something like when matched then \"matched\" when not changed \"value changed\". I'm looking for output something like below: sql_id comaparion outcome dmqb1hzrf5uxh No change in the plan 74anujtt8zw4h plan changed Can I do something like this? select sql_id,case when ( select sql_id,OPERATION,options from a where sql_id='dmqb1hzrf5uxh' minus select sql_id,OPERATION,options from b where sql_id='dmqb1hzrf5uxh') is null then 'matched' else 'changed' end as status; I am comparing the explain plans before and after patch. The table 'A' is before patch result of the sqlid and table 'B' is after patch result. Now I want to compare the plans in both the tables. I want to compare the plan by using a query.", "A different approach in distributing $8$ distinct balls into $6$ distinct boxes Find the number of ways in distributing $8$ distinct balls into $6$ distinct boxes such that there is at least $1$ ball in each box. We are well acquainted with the traditional Inclusion-Exclusion principle in solving this and it will come up as $191520$ ways. I tried in this way: When we distribute $8$ balls into $6$ boxes we have two possible cases Case $1.$ There are exactly $2$ boxes with $2$ balls each Case $2.$ There is exactly $1$ Box with $3$ balls in it. For Case $1$, the distribution is done by choosing $2$ boxes from $6$ boxes and $2$ balls from $8$ balls and those two balls can be arranged in $2!$ ways. But I require another two balls from remaining $6$ balls to be placed in each of these two boxes which can be done in $\\binom{6}{2} \\times 2!$ ways. Finally remaining $4$ balls can be distributed in remaining $4$ boxes in $4!$ ways. So total number of ways for Case $1.$ is $$\\binom{6}{2} \\times \\binom{8}{2} \\times 2! \\times \\binom{6}{2} \\times 2! \\times 4!=604800$$ For Case $2$, the number of ways is $$\\binom{6}{1} \\times \\binom{8}{3} \\times 5!=40320$$ I am pretty sure the value obtained for Case $2.$ is correct. but I could not find where I went wrong in Case $1.$", "Can I mix sources from different ubuntu versions? As we know that we are using for installing packages and repositories configuration file located at /etc/apt/sources.list. I am using Ubuntu 12.10 (Quantal Quetzal) which reaches . That means no updates or support. So, the question is, can I use sources.list file from another version, say Ubuntu 12.04 LTS, and will it negatively affect the system.", "Finding the derivatives of sin(x) and cos(x) We all know that the following (hopefully): $$\\sin(x)=\\sum^{\\infty}_{n=0}(-1)^n \\frac{x^{2n+1}}{(2n+1)!}\\ , \\ x\\in \\mathbb{R}$$ $$\\cos(x)=\\sum^{\\infty}_{n=0}(-1)^n \\frac{x^{2n}}{(2n)!}\\ , \\ x\\in \\mathbb{R}$$ But how do we find the derivates of $\\sin(x)$ and $\\cos(x)$ by using the definition of a derivative and the those definition above? Like I should start by doing: $$\\lim_{h\\to\\infty}\\frac{\\sin(x+h)-\\sin(x)}{h}$$ But after that no clue at all. Help appreciated!", "New SSD problem I've just installed a new SSD replacing an HDD in my old (late 2008) iMac. When I switched it on all I got on screen was a question mark. On the advice of my son I tried cmdR during switch on with no result. I then tried alt which at least got me a cursor on the screen, but nothing else. Any suggestions? I've got everything backed up on an external Hard Drive, by the way.", "I'm using using algorithm2e package with the following settings: \\usepackage[ruled,vlined,linesnumbered,noresetcount]{algorithm2e} But for some subset of algorithms in the same document, I want to use this setting: \\usepackage[boxed]{algorithm2e} Is there a way to override the default setting just for a subset? I found a similar question: Here newenvironment is used to override the default setting of an option. But I want to override the option itself. I wish there was a way to load a package several times with different options for each instance.", "Android and setting width and height programmatically in dp units", "Are (un)tapped permanents still legal targets for \"(un)tap target permanent\" effects? So I noticed that many cards with tap-effects ship with a clause specifying that they can only be used on untapped permanents, such as and . So here's my question: Doesn't that imply that, given the right situation, one can legally tap an already tapped permanent? I'll give an example of the kinda scenarios this is relevant for: Can activate her first ability when no untapped cards are around? Or, thinking untap-effects, could I bounce a forest with even when there isn't a tapped creature available? Notice that, unlike the previous batch of examples, the wording on these lacks the clause restricting their use to un/tapped permanents - does that mean that they aren't? Any kind of clarification would be greatly appreciated here.", "How do the Chitauri \"ships\" propel themselves? In the 2012 The Avengers film, the Chitauri army arrives through the portal along with these big robot alien whale Chitauri dudes. Here's one chasing Iron Man: These guys basically swim through the air like... giant robot alien whales. I don't see any means of propulsion. Other, more humanoid Chitauri soldiers fly around on things that seem to be mechanical &quot;speeders&quot; of sorts. What are these guys? Are they ships, creatures, or both? Is there an explanation anywhere in the Avengers universe for how they defy gravity and swim through the air?" ]

[ "Square bracket notation for dimensions and units: usage and conventions One of the most useful tools in is the use of square brackets around some physical quantity $q$ to denote its dimension as $$[q].$$ However, the precise meaning of this symbol varies from source to source; there are a few possible interpretations and few strict guidelines. What conventions are there, who uses them, and when am I obliged to follow them?", "Viewshed Analysis With GDAL I am looking to perform a simple (one observer location) viewshed analysis on a standard DEM using GDAL (either python or .NET bindings). I have searched, but haven't found any readily available implementation. Can anyone point me in the right direction?", "Cycles: How do I exclude the Environment Texture from reflections?", "Will spoiled food always make you sick?", "What is the limit of", "When polynomials f(x) and f'(x) are relatively prime, f(x) has no repeated roots. Why? The problem is to show that a polynomial $f(x) \\in F[x]$ (F is a field) has no repeated roots if and only if f(x) and f'(x) (the derivative of f(x)) are relatively prime. I've managed to prove one direction of this equivalence (if there are no repeated roots, f(x) and f'(x) are relatively prime), but the other one gives me headaches... can anyone help out?", "Custom thumbnailers don’t work on Ubuntu 18.10 and 18.04 Recently I had a bunch of my own scripts for the thumbnails in Nautilus: , , office documents and so on. Seems like either I’m doing something wrong (thumbnail generation behavior changed), or custom thumbnailes don’t work in latest GNOME at all, even my previous scripts, which worked smoothly on previous versions of Ubuntu. I’ve done some research, tried to run a simple script (see below) and it didn’t work out. My test thumbnailer in /usr/share/thumbnailers/z.thumbnailer: [Thumbnailer Entry] Exec=/home/maximal/thumb.sh %s %i %u %o MimeType=image/webp;image/x-webp Where /home/maximal/thumb.sh is: #!/bin/bash echo $0 &gt;&gt; /home/maximal/thumb.log echo $1 &gt;&gt; /home/maximal/thumb.log echo $2 &gt;&gt; /home/maximal/thumb.log echo $3 &gt;&gt; /home/maximal/thumb.log echo $4 &gt;&gt; /home/maximal/thumb.log Then, when I remove thumbnail cache rm -rf ~/.cache/thumbnails and restart Nautilus nautilus -q, my log file doesn’t contain anything and ~/.cache/thumbnails/fail/gnome-thumbnail-factory contains all the failed thumbs (looks like corrupted/empty PNGs): So, apparently, Nautilus even didn’t try to execute my thumbnailer script. When I try to run thumb command itself, it works perfectly. For example convert through cwebp|dwebp package: convert -thumbnail 256x256 file.webp png:file.webp.png When I wrap this command to a thumbnailer, it looks like it wasn’t even requested to run by Nautilus. [Thumbnailer Entry] Exec=convert -thumbnail %sx%s %i png:%o MimeType=image/webp;image/x-webp; Exactly the same situation occurs with other my thumbnailers: audio waveforms, office documents, photoshop files and so on. Could anyone help?", "Show $\\inf_f\\int_0^1|f'(x)-f(x)|dx=1/e$ for continuously differentiable functions with $f(0)=0$, $f(1)=1$. Let $C$ be the class of all real-valued continuously differentiable functions $f$ on the interval $[0,1]$ with $f(0)=0$ and $f(1)=1$. How to show that $$\\inf_{f\\in C}\\int_0^1|f'(x)-f(x)|dx=\\frac{1}{e}?$$ I have been able to show that $1/e$ is a lower bound. Indeed, $$\\begin{align*} \\int_0^1|f'(x)-f(x)|dx &amp;= \\int_0^1|f'(x)e^{-x}-f(x)e^{-x}|e^xdx \\\\ &amp;\\geq \\int_0^1\\left(f'(x)e^{-x}-f(x)e^{-x}\\right) dx \\\\ &amp;= \\int_0^1 \\frac{d\\left(f(x)e^{-x}\\right)}{dx}dx \\\\ &amp;= f(1)e^{-1}-f(0)e^{0}\\\\ &amp;=\\frac{1}{e}. \\end{align*}$$ But how to show this is the infimum? Is there a function $f\\in C$ such that we get $\\int_0^1|f'(x)-f(x)|dx=1/e$?", "Why are these numbers not equal?", "How to change SQL Server collation", "Is an apostrophe with a decade (e.g. 1920’s) generally considered “incorrect”? I typically don’t use an apostrophe with plurals in any situation, but I always assumed that the use of an apostrophe in constructions like acronyms: Forty BA’s were given out to students this year. or numbers: Though the greatest period instability occurred during the 1950’s when. . . . was more or less ok. I would personally use BAs and 1950s here, but I've never thought the apostrophe in this case was necessarily “incorrect”. What say ye?", "I just noticed a weird thing in my reputation tab on StackOverflow. That last question mentioned (but not linked, had to find it via search): I must have amnesia as I have no memory of ever interacting with this post. I don't even know what xampp and pdftk are so I don't know why I would even be interested in such a question. 2 reputation points more or less is not a big deal, but the fact I got rep change from question I've never seen before is odd and I'm wondering what happened.", "Q1. Find the general solution to the difference equation $$ a_{n} - 4a_{n-1} + 3a_{n-2} = 6 $$ Q2. Solve the difference equation $$ a_{n} - a_{n-1} - 2a_{n-2} = 0, a_0 = 2, a_1 = 4 $$ I am completely lost in solving recurrence relation questions. Can anyone guide me in steps to solve the following 2 questions?", "Get on what tile has mouse clicked", "How to recover files after deleted my Ubuntu partition?", "Do indexes work with \"IN\" clause", "Movie Identification - 1990s VHS Sci-Fi/Horror", "What is the typical orbital life of an artificial satellite? The orbit of satellites around Earth eventually decays, or so I read. This is typically caused either by atmospheric drag, or by tides. I would assume most satellites have a limited service life in orbit. Hence the question - What is the typical orbital life of a satellite? How long before it's successor must be launched into orbit ? EDIT: For instance, a weather satellite", "Newer \"mainline\" versions of the kernel are available from the , e.g. 3.4 and 3.5, while Ubuntu 12.04 is on 3.2. What are the mainline kernels? Are they better than my existing kernel? What are the pros and cons of upgrading to a mainline kernel? Will I easily be able to go back?", "Show that $\\frac 1{1+x+y^{-1}}+\\frac1{1+y+z^{-1}}+\\frac1{1+z+x^{-1}}=1$ if $xyz=1$" ]

[ "How to load a .NET assembly for reflection operations and subsequently unload it?", "I was wondering if there was any was I could right click inside any instance of a \"Finder\" window such that I have an option that says \"Open Terminal Here\". It would be really helpful.", "Status of B1/B2 visa after citizenship change? I have a valid B1/B2 visa valid to US till March 2019 on Indian passport, I changed my citizenship to Australian. Is my B1/B2 visa on Indian passport valid?", "How did the transdimensional Edo god (Edo lord) come to be the overseer of the Edo?", "The isomorphism $\\mathbb{Z}[i]/(a+bi) \\cong \\Bbb Z/(a^2+b^2)\\Bbb Z$ is , when the integers $a$ and $b$ are coprime. But what happens when they are not coprime, say $(a,b)=d&gt;1$? — For instance if $p$ is prime (which is not coprime with $0$) then $$\\mathbb{Z}[i]/(p) \\cong \\mathbb{F}_p[X]/(X^2+1) \\cong \\begin{cases} \\mathbb{F}_{p^2} &amp;\\text{if } p \\equiv 3 \\pmod 4\\\\ \\mathbb{F}_{p} \\times \\mathbb{F}_{p} &amp;\\text{if } p \\equiv 1 \\pmod 4 \\end{cases}$$ (because $-1$ is a square mod $p$ iff $(-1)^{(p-1)/2}=1$). — More generally, if $n=p_1^{r_1} \\cdots p_m^{r_m} \\in \\Bbb N$, then each pair of integers $p_j^{r_j}$ are coprime, so that by CRT we get $$\\mathbb{Z}[i]/(n) \\cong \\mathbb{Z}[i]/(p_1^{r_1}) \\times \\cdots \\times \\mathbb{Z}[i]/(p_m^{r_m})$$ I was not sure how to find the structure of $\\mathbb{Z}[i]/(p^{r}) \\cong (\\Bbb Z/p^r \\Bbb Z)[X] \\,/\\, (X^2+1)$ when $p$ is prime and $r&gt;1$. — Even more generally, in order to determine the structure of $\\mathbb{Z}[i]/(a+bi)$ with $a+bi=d(x+iy)$ and $(x,y)=1$, we could try to use the CRT, provided that $d$ is coprime with $x+iy$ in $\\Bbb Z[i]$. But this is not always true: for $d=13$ and $x+iy=2+3i$, we can't find Gauss integers $u$ and $v$ such that $du + (x+iy)v=1$, because this would mean that $(2+3i)[(2-3i)u+v]=1$, i.e. $2+3i$ is a unit in $\\Bbb Z[i]$ which is not because its norm is $13 \\neq ±1$. — I was not able to go further. I recall that my general question is to known what $\\mathbb{Z}[i]/(a+bi)$ is isomorphic to, when $a$ and $b$ are integers which are not coprime (for instance $a=p^r,b=0$ or $d=(a,b) = a^2+b^2&gt;1$). Thank you for your help!", "Light emission from the vicinity of a black hole The photograph of the black hole, at the centre of galaxy M87, is now a part of human history. We are told that the red-colour is caused by hot gas, matter &amp; radiation around the \"edge\", the Event Horizon. Given the power of the gravitational forces emanating from black hole, why aren't these three things drawn into the abyss? If light is bent/ drawn into the BH, how does this red image arise? The logic, here, would be that a body, on the Event Horizon, is immune from the gravity--which sounds pretty fatuous?", "How to switch from Resident visa to Tourist visa status in the Schengen area? I have a 1-year residence permit from one Schengen country that is now expiring. Upon its expiration, I would like to get my 90/180 days validity as a tourist to stay, or return here as soon as possible. I understand that the tourist short-stay scheme is based on the 90/180 days \"counter\". But what happens if my previous stay was not tourism but residence (as searching year). Wouldn't that mean that I can quickly exit and re-enter the Schengen area to activate my tourist stay? Also, is there a way to change this purpose of stay without exiting the Schengen area?", "Where can I download Windows 8 legally, from Microsoft?", "Unable to set DYLD_FALLBACK_LIBRARY_PATH in shell on OSX 10.11.1", "I am looking for a way to replace a string in a file with a string that contains a slash by using sed. connect=\"192.168.100.61/foo\" srcText=\"foo.bar=XPLACEHOLDERX\" echo $srcText | sed \"s/XPLACEHOLDERX/$connect\" The result is: sed: -e Expression #1, Character 32: Unknown option for `s'", "Do you ever center AND standardize variables in multiple regression? It seems as if standardization would automatically center variables...is this true?", "Turning vector grid into individual shapefiles using QGIS? I am using QGIS and I created a vector grid on a crop field in order to cut it into plots. I want to save each grid cell into individual polygon shapefiles automatically. Here is an example of a vector grid I would like to split into 117 shapefiles: Eventually, I did it manually with the selection tool and \"Save as\" but it is really time-consuming when there are more than 100 plots to save. Is there any way to do it faster and more automatically? Each plot as an attribute named \"Plot\" that can discriminate against them (basically being id + 1). It's the attribute used here to label them.", "Was it just coincidence that Tahir Mahmood went on stage?", "Is acceleration due to gravity constant?", "I have my bachelors degree in engineering science: computer science, option electrotechnic. I have a good understanding of basic mechanics and dynamics, calculus (differential equations). The books I'm now having a look at are: What book do you recommend for studying fluid dynamics on my own and why?", "What is the most efficient way to make money? What are some of the most efficient ways to make money? Based on: time initial investment required progress (in the game) special equipment/gear", "I'd like to use JavaScript to calculate the width of a string. Is this possible without having to use a monospace typeface? If it's not built-in, my only idea is to create a table of widths for each character, but this is pretty unreasonable especially supporting and different type sizes (and all browsers for that matter).", "Who are the Steam Mascots? So with the Steam Summer Sale in full swing, I've finally taken notice of the Steam Mascots. Judging by the latest background, the black one, at least, has a name: Cyl. Do the other two have names as well? Are there only these three? What's their story?", "Cann I use a 19.5V 4.62A laptop charger for 19V 4.74A laptop?", "Sequence of differentiable functions Let $f_n$ be a sequence of differentaible functions on $[0,1]$ to $\\mathbb{R}$ converging uniformly to a function $f$ on $[0,1]$, Then $f$ is differentiable and Riemann integrable there $f$ is uniformly continuous and R-integrable $f$ is continuous, need not be differentiable on $(0,1)$ and need not be R-integrable on $ [0,1]$, $f$ need not be continuous. Well I think 2 is only correct statement as every $f_n$ are differentiable on $[0,1]$ hence uniformly contnous, and as they converge uniformly to $f$ on $[0,1]$ so $f$ is uniformly continuous and every continuous function is rieman integrable..Am I correct?" ]

[ "Computing sums of divisors in $O(\\sqrt n)$ time? I have a sequence: $1,3,5,8,10,14,16,20,23,27,\\dots$ I know that the recursive relation is: $$p[i] := p[i-1] + \\text{number of factors of $i$}, \\quad \\text{with $p[1]=1$.}$$ How do I solve this recursive relation in $O(n^{0.5})$ time? I have to write a program for it, and $n$ can be as large as $10^9$. So, some appropriate precomputation and prestorage is allowed, provided that they comply (memory and time wise) with the range of $n$.", "How does new shield system work? After the upgrade I can't figure out how the new shield system works. I have the option to discard the shield, and I notice I have a new potion in the inventory. More importantly, I got attacked (and lost) twice in a short amount of time and don't have a shield. When do you now get shield?", "Why is AES resistant to known-plaintext attacks? At least it's my understanding that AES isn't affected by known-plaintext. Is it immune to such an attack, or just resistant? Does this vary for chosen-plaintext?", "3d transforms on SVG element", "Basic question, how do I resume interrupted / failed downloads in Firefox?", "What happens to the energy when waves perfectly cancel each other? What happens to the energy when waves perfectly cancel each other (destructive interference)? It appears that the energy \"disappear\" but the law of conservation of energy states that it can't be destructed. My guess is that the kinetic energy is transformed into potential energy. Or maybe it depends on the context of the waves where do the energy goes? Can someone elaborate on that or correct me if I'm wrong?", "Why have we chosen our number system to be decimal (base 10)? After learning about the binary number system (only 2 symbols, i.e. 0 and 1), I just thought why did we adopt the decimal number system (10 symbols) after all? I mean if you go to see, it's rather inefficient when compared to the octal (8 symbols) and the hexadecimal (16 symbols)?", "UILabel truncate tail and skip not complete word", "Interpretation of LASSO regression coefficients I'm currently working on building a predictive model for a binary outcome on a dataset with ~300 variables and 800 observations. I've read much on this site about the problems associated with stepwise regression and why not to use it. I've been reading into LASSO regression and its ability for feature selection and have been successful in implementing it with the use of the \"caret\" package and \"glmnet\". I am able to extract the coefficient of the model with the optimal lambda and alpha from \"caret\"; however, I'm unfamiliar with how to interpret the coefficients. Are the LASSO coefficients interpreted in the same method as logistic regression? Would it be appropriate to use the features selected from LASSO in logistic regression? EDIT Interpretation of the coefficients, as in the exponentiated coefficients from the LASSO regression as the log odds for a 1 unit change in the coefficient while holding all other coefficients constant.", "CPU governor changes automatically to \"performance\" under load I have a Lenovo T570 with Xubuntu 18.04 LTS. My current issue is that my cpu speed stepping is kind of going nuts and does what ever it thinks its best. Sample: when I run my IDE and cpu load increases during build time, the governor changes automatically. I caught the moment during compiling my project with the following call: martin@martin-ThinkPad-T570:~$ while cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor; do sleep 1; done powersave powersave performance performance cpufreq-info tells me this: martin@martin-ThinkPad-T570:~$ cpufreq-info cpufrequtils 008: cpufreq-info (C) Dominik Brodowski 2004-2009 Report errors and bugs to [email protected], please. analyzing CPU 0: driver: intel_pstate CPUs which run at the same hardware frequency: 0 CPUs which need to have their frequency coordinated by software: 0 maximum transition latency: 4294.55 ms. hardware limits: 400 MHz - 3.50 GHz available cpufreq governors: performance, powersave current policy: frequency should be within 3.50 GHz and 3.50 GHz. The governor \"performance\" may decide which speed to use within this range. current CPU frequency is 3.25 GHz. analyzing CPU 1: driver: intel_pstate CPUs which run at the same hardware frequency: 1 CPUs which need to have their frequency coordinated by software: 1 maximum transition latency: 4294.55 ms. hardware limits: 400 MHz - 3.50 GHz available cpufreq governors: performance, powersave current policy: frequency should be within 3.50 GHz and 3.50 GHz. The governor \"performance\" may decide which speed to use within this range. current CPU frequency is 3.36 GHz. analyzing CPU 2: driver: intel_pstate CPUs which run at the same hardware frequency: 2 CPUs which need to have their frequency coordinated by software: 2 maximum transition latency: 4294.55 ms. hardware limits: 400 MHz - 3.50 GHz available cpufreq governors: performance, powersave current policy: frequency should be within 3.50 GHz and 3.50 GHz. The governor \"performance\" may decide which speed to use within this range. current CPU frequency is 3.26 GHz. analyzing CPU 3: driver: intel_pstate CPUs which run at the same hardware frequency: 3 CPUs which need to have their frequency coordinated by software: 3 maximum transition latency: 4294.55 ms. hardware limits: 400 MHz - 3.50 GHz available cpufreq governors: performance, powersave current policy: frequency should be within 3.50 GHz and 3.50 GHz. The governor \"performance\" may decide which speed to use within this range. current CPU frequency is 3.36 GHz. Please take a look at current policy: frequency should be within 3.50 GHz and 3.50 GHz. The governor \"performance\" may decide which speed to use Afterwards to go back to powersave I use my little script: martin@martin-ThinkPad-T570:~$ cat cpu_freq_save.sh #!/bin/bash sudo cpufreq-set -g powersave -c 0 --min 400MHz sudo cpufreq-set -g powersave -c 1 --min 400MHz sudo cpufreq-set -g powersave -c 2 --min 400MHz sudo cpufreq-set -g powersave -c 3 --min 400MHz Which resets the min frequency and the governor but as soon as I compile again with my IDE every time the governor and the min frequency changes again. Any idea how I can disable that automatic change? PS: If you need more details, just tell me where to find them and I will provide them", "Why is $1^{\\infty}$ considered to be an indeterminate form", "I was wondering if someone could critique my argument here. The problem is to find the probability where exactly 2 people in a room full of 23 people share the same birthday. My argument is that there are 23 choose 2 ways times $\\displaystyle \\frac{1}{365^{2}}$ for 2 people to share the same birthday. But, we also have to consider the case involving 21 people who don't share the same birthday. This is just 365 permute 21 times $\\displaystyle \\frac{1}{365^{21}}$. To summarize: $$\\binom{23}{2} \\frac{1}{365^2} \\frac{1}{365^{21}} P\\binom{365}{21}$$", "How can I extract menthol powder from fresh mint/peppermint?", "Low current battery monitoring", "Is the uncertainty principle just saying something about what an observer can know or is it a fundamental property of nature? I ask this question because I have read two different quotes on the that don't seem to match very well. There are similar questions around here but I would like an explanation that reconciles these two interpretations specifically: Feynman talks about the uncertainty principle in one of his lectures and mentions it as the reason why electrons don't crash into the atom's nucleus: If they did they would have an exact location and momentum which is not allowed by the uncertainty principle. In saying this it is clear that the uncertainty principle is a fundamental property of nature because it has an effect on where an electron can reside. Recently I read - somewhere else but I forgot where exactly - an account of the uncertainty principle where there was explained how we can measure position of a particle by firing another particle into it, the collision disturbs the velocity of the observed particle therefore we can not know its momentum anymore. Now, 2) very much seems like a limitation of what the observer can know, while 1) attributes a fundamental property of nature to it (electrons don't crash into the nucleus). What is the correct way to think about this?", "I'm a Windows/Mac/Ubuntu and Android user, so I know what I'm talking about, when I say: How do I open binary image files? (.img) They just won't open, on any OS… I'm an Android dev… I'm currently working on a ROM, (I also program, using Windows) but I need to extract files, from .img files. I've converted them to .ext4.img but they just aren't recognized by Linux (Definitly not by Android), by Mac OS or Windows. In other words, I can't open, extract or mount them. Can anyone help me? I'm kinda confused…", "Finding solution of non linear DE $x\\ddot{x}-\\dot{x}^2=1$ I am looking for help on how to find the solution of the following differential equation, $$x\\ddot{x}-\\dot{x}^2=1,$$ which comes from solving the Euler-Lagrange equations for the lagrangian $L=x\\sqrt{\\dot{x}^2+1}$. It is from an exercise in my field theory course. My professor provided me with the solution $x(t)=c_1\\cosh{\\left(\\frac{t-c_2}{c_1}\\right)}$, which is a solution when plugged into the equation, but does not give any derivation. Is there a way to solve this DE other than an educated guess? If so how?", "Proof: $\\|X\\|_2\\leq \\sqrt{n}\\|X\\|_\\infty$ (Euclidean Norm) Proof that $\\|X\\|_2\\leq \\sqrt{n}\\|X\\|_\\infty$, if $x \\in \\mathbb{R^n}$. With that, proof $\\|X\\|_\\infty \\to 0 \\implies \\|X\\|_2\\to 0$ I'm stuck: $\\|X\\|_2= \\sqrt{x^2_1+x^2_2+...+x^2_n}\\leq\\sqrt{n}\\sqrt{x^2_1+x^2_2+...+x^2_n}$ I don't know how to use the fact: $\\|X\\|_\\infty=\\max(|x_1|,|x_2|,...,|x_n|)$", "I am installing Ubuntu 16.04 in an Intel NUC computer with UEFI enabled. I am using an SSD from another computer. During the installation I chose Erase the disk and make a new full install At the end of the process I see: grub-efi-amd64-signed failed installation /target/ Ubuntu 16.04 And the system does not boot. I tried to use boot-repair but apparently it does not solve the problem.", "Use of \"save\" or \"save for\" in sentences" ]

[ "Can I use Facebook's fb:friend-selector in an iframe?", "Methods for autocompletion in TexStudio don't work I've made a mymacros.sty file which I would like my LaTeX files to be able to access with commands that I've defined. I've managed to get it to work by putting \\usepackage{mymacros} in my preamble. However when I try to autocomplete I can't. I looked at this question: ), which recommends 3 ways of doing this, none of which work for me. The first it recommends is to have mymacros.sty open in the editor. But this doesn't work. The second is to activate the option Editor -> Automatically load included files in the configure TeXstudio options panel. However while I have an Editor tab , there is no such option there. The third is to using .cwl files, however I'm not sure how to go about this. In the completion tab I've noticed that there is a mymacros.sty option that has come up, which I ticked but that has had no effect. Do I need to make my own mymacros.cwl file? I've tried to look this up but haven't had any luck. Anyone have any ideas? Thanks in advance!", "What is batch size in neural network? I'm using Python Keras package for neural network. This is the . Is batch_size equals to number of test samples? From Wikipedia we have information: However, in other cases, evaluating the sum-gradient may require expensive evaluations of the gradients from all summand functions. When the training set is enormous and no simple formulas exist, evaluating the sums of gradients becomes very expensive, because evaluating the gradient requires evaluating all the summand functions' gradients. To economize on the computational cost at every iteration, stochastic gradient descent samples a subset of summand functions at every step. This is very effective in the case of large-scale machine learning problems. Above information is describing test data? Is this same as batch_size in keras (Number of samples per gradient update)?", "I just would like to know if a question or an answer saved draft is visible to someone else, apart from the OP. Will a copy of a saved draft remain visible even after it has been deleted? Who has access to it?", "I'm trying to compute the difference between the output of two awk commands but my simple attempts at it seem to be failing. Here is what I'm trying: diff $(awk '{print $3}' f1.txt | sort -u) $(awk '{print $2}' f2.txt | sort -u) This doesn't work for reasons unknown to me. I was under the assumption that $() construct was used to capture the output of another command but my \"diff\" invocation fails to recognize the two inputs given to it. Is there any way I can make this work. By the way, I can't use the obvious solution of writing the output of those two commands to separate files given that I'm logged on to a production box with no 'write' privileges.", "What punctuation should follow after a list introduced by a colon? The whole department: John, Jeff, Jean, and the accountant [?] were thrown into jail.", "I am writing a cover letter and CV using moderncv. Everything works fine so far, but the text in the cover letter is not justified. I think it is good that it is not hyphenated, but it would look much nicer if the text was justified. Here is a minimal example: \\documentclass{moderncv} \\moderncvstyle{classic} \\usepackage{lipsum} % just for dummy text \\firstname{John} \\familyname{Doe} \\begin{document} \\recipient{Prof.\\ Dr.\\ Foo Bar}{} \\opening{Dear Professor Dr.\\ Bar,} \\closing{Yours sincerely,} \\enclosure[Attached]{curriculum vit\\ae} \\makelettertitle \\lipsum[1] \\makeletterclosing \\clearpage \\makecvtitle \\section{Education} \\cventry{2009--present}{PhD Student}{here}{and}{there}{} \\end{document}", "The LOTR wiki Eru Ilúvatar intervened in the history of Arda: creating Elves and Men removing Aman from the spherical Earth resurrecting Gandalf making Gollum trip In a letter written by Tolkien, he stated that Eru again intervened, this time in the Third Age, causing Gollum to trip and fall into the fires of Mount Doom while still holding the One Ring, thus destroying it. Is this correct? If so, what letter is this, and exactly what did Tolkien say?", "Displaying row/column of point in raster using QGIS? Is it possible in QGIS to display column and row index of pixel in raster? I mean something similar to value tool.", "What is the \"last\" data that get's backed up, when running pg_dump on a live server? I'm wondering: If I start doing a pg_dump of a very large database (it would take hours), that is still running actively receiving writes, what is then the last data that goes into the backup? Is it: The data as-it-was, at the point in time where the pg_dump command was initiated. The last changes that it encountered at some point where it was dumping that individual record. Something else. Bonus question: If I'm trying to dump a database as part of trying to rescue it from corrupt data, will it then make any difference whether I use the directory format or the custom format?", "Isometries of the sphere $\\mathbb{S}^{n}$", "A few years ago I saw a scifi movie about a group of travelers stranded at what I believe might have been a bus station (I don't remember that detail with any certainty). There were 2 children (a boy and a girl) who were running around and everyone thought they belonged to someone else there. As it turned out, the children were aliens that reverted to their true form and began hunting down the travelers. I've been searching all over the internet but can't come up with the name of the movie. Does anyone know the name of it?", "For only my index pages, I am receiving this warning in Google Search Console: Duplicate, submitted URL not selected as canonical I know that this occurs because Google is attempting to track both the default landing \"page\" (i.e. www.domain.example/) and the page to which to which DirectoryIndex points (i.e. www.domain.example/index.html). They are, in fact, the same page, and so the warning is the result of a false positive. Two questions for our community: Why does Google not conflate these and count them as a single page? Alternately, is there something wrong with my set up if this has happened? I can easily force both pages to point to a single canonical URL. But which is preferable, \"/\" or \"index.html\"?", "How to recover a deleted NTFS partition with data I am on Ubuntu 12.04 64-bits I accidentally deleted a NTFS 255 GB partition using Gparted, and yes it contains LOTS of important data. Upon realizing the deletion I haven't yet created any file-system on it. So it still shows Unallocated. I tried Testdisk , but it shows entire partitions created from the beginning. This sdb is my secondary drive with Xubuntu and Kubuntu on it. And that 255 GB NTFS partition was cross platform storage drive. I am currently in sda with Ubuntu and Win7 in dual boot, which enables me to use it as Safe recovery option rather then Live USB drive. First , should i allocate it to ? file-System for better recovery . Second , i really need to recover data from this drive so please give me possible suggestions and proven methods of data recovery. Third ,does Testdisk requires deleted partition to be allocated for its recovery . I am currently trying the answer seen here with Testdisk scanning for partition second time, hoping to recover it. It looks a duplicate but i can't confirm if the OP got it right. Since my first doubt is to allocate it or not. If any clarification required please do comment ,i will add it. Edit: TestDisk deeper search results. The following partitions can't be recovered: Partition Start End Size in sectors &gt; HPFS - NTFS 22241 107 11 55592 3 27 535777280 FAT32 LBA 274460 158 19 460576 228 16 2989957948 NTFS, 274 GB / 255 GiB &amp; for FAT32 LBA 1530 GB / 1425 GiB", "I found this interesting problem in : Given a point $P$ in space, and given a piece of malleable material of constant density, how should you shape and place the material in order to create the largest possible gravitational field at $P$? Any ideas?", "OS: Windows 7. I want install Linux Ubuntu on portable external Hard Drive USB 2.0. I read a variety of methods, but I'm confused by contradictory advices and methods. Actually, installing Ubuntu on anything other than clean PC looks much more complicated than installing Windows. I need to have Ubuntu package + Python 2.7 + C compiler installed. My external hard drive is partially filled, I need to keep all files. Will Ubuntu run entirely on external hardrive, without writing anythinhg to Windows system folders and to registry? Can anyone post detailed guide how install Ubuntu on external hard drive?", "Why do you need 2 resistors when hooking up a transistor as a switch What is the point of R2 in the following diagram: I get that R1 controls the current to the Base, but what does R2 do?", "$ is not a function in drupal 7 theme", "How to implement a \\tomorrow in latex I was asked how to implement a \\tomorrow macro in TeX/LaTeX. While I could come up with a reasonably good solution, working for one document class, I don't see how that could be achieved in a document class agnostic way. I found , but even though the date arithmetic may be of use, it assumes a specific format for the date (which also is wrong for the locale I reside in). Does anyone have a reasonably portable solution? Is this even possible?", "Does the ANSI standard mandate the logical operators to be short-circuited, in either C or C++? I'm confused for I recall the K&amp;R book saying your code shouldn't depend on these operations being short circuited, for they may not. Could someone please point out where in the standard it's said logic ops are always short-circuited? I'm mostly interested on C++, an answer also for C would be great. I also remember reading (can't remember where) that evaluation order isn't strictly defined, so your code shouldn't depend or assume functions within an expression would be executed in a specific order: by the end of a statement all referenced functions will have been called, but the compiler has freedom in selecting the most efficient order. Does the standard indicate the evaluation order of this expression? if( functionA() &amp;&amp; functionB() &amp;&amp; functionC() ) cout&lt;&lt;\"Hello world\";" ]

[ "iOS 9.2 double touch fingerprint sensor I was messing around this morning and found that if I quickly double touch (NOT double-click) the fingerprint sensor on my iPhone 6S+ (iOS 9.2), the current app (or the home screen) slides down to the bottom half-screen, showing a blurred home screen background on the top half. It doesn't matter if I use a finger that the sensor recognizes. It goes back to normal after about 8 seconds or if you double-touch again, but I can't figure out what this mode is for?? Is this a bug or some hidden feature I haven't heard about yet?", "There are many documentaries, forums, blogs and more dedicated to . I have been frantically searching for an answer to my question however none of my sources have clarity to the matter of hand. I would really love a clear explanation to: What exactly is Dark Matter? Please help me to have a clear understanding.", "How to tell which row number is clicked in a table?", "Prove that the additive groups $\\mathbb{R}$ and $\\mathbb{Q}$ are not isomorphic. Is there a better (or other) way(s) to prove the following statement? Also, the same argument works for multiplicative groups $\\mathbb{R}-\\{0\\}$ and $\\mathbb{Q}-\\{0\\}$, right? Problem Prove that the additive groups $\\mathbb{R}$ and $\\mathbb{Q}$ are not isomorphic. Solution By cantor's diagonal argument, there is no possible bijection between $\\mathbb{Q}$ and $\\mathbb{R}$. Since an isomorphism needs to be a bijection, there is no possible isomorphism between the additive groups $\\mathbb{R}$ and $\\mathbb{Q}$. Thanks", "How do I cherry pick packages from a PPA? Is there a way to cherry pick packages from a ppa repository you add? That is, to exclude some from updating while including others? For example, I want just the chromium-browser package from but not the others. So I don't want my sudo apt-get upgrade to have that ppa's other (besides chromium-browser) packages install over my existing ones, just that one. I realize this is a license to shoot myself in the foot if I misread dependencies and exclude ones that are needed to ones that I included, but I know for a fact in this case that the other packages are not dependencies for that one. Is this at all possible? Maybe there is some whitelist/blacklist file or something?", "Integrate JavaScript in JSF composite component, the clean way", "Does there exist a polynomial $p(x) \\in \\mathbb C[x]$ such that $p(x) \\notin \\mathbb R[x]$ and $p(x)p(-x)=p(x^2)$ ? I have noticed that if $a_n$ is the leading coefficient of $p(x)$ then $a_n=(-1)^n $, so the leading coefficient cannot be imaginary; also $p(0)^2=p(0)$ so the constant term also is real. Please help. Thanks in advance.", "Test -n gives unexpected result I understand test -n &lt;expression&gt; to return false if the expression evaluates to a string length of greater than 0. Why then does the following happen? Macbook:~ echo ${#undeclared_variable} 0 Macbook:~ test -n $undeclared_variable &amp;&amp; echo Foo Foo Bash 4.x My expectation is that since test -n $undeclared_variable should evaluate false, that Foo should not be echoed. If I use [[ ]] instead of test, it works as expected.", "Entropy of sum is sum of entropies", "How do I create an immutable Class?", "I have recently noticed a rather large amount of small worms in the fresh cod I am buying. I have tried to take them out as much as I can and of course have spoken to my fish supplier about them, but he assures me they are harmless. However, I don't believe my customers would be as assured. Is it okay to serve this fish, taking into account I might miss a worm or two?", "Show that computation of all such expressions will result in the same element of $X$", "I am trying to create a low poly face with a face from a .png file. The issue is I already have material placed for hair and skin, as shown in the picture below. I have created a .png file with a face which I would like to overlay over the skin material on the front of the head. All examples I searched so far assume I also want the color of the material from the .png texture. Update: I added UVMapping, changed view to texture, made sure one face is on the eye but nothing is displayed..... see image... I don't know what is going on.", "How to prove a matrix is nilpotent? Given an $n\\times n$ upper triangular matrix $A$ with zero on main diagonal, show that $A^n = 0$. I did some matrix operation and noticed that the diagonal moves up, ultimately all entries will be zero. Is there a nicer way to do it?", "I'm trying to put together a comprehensive regex to validate phone numbers. Ideally it would handle international formats, but it must handle US formats, including the following: 1-234-567-8901 1-234-567-8901 x1234 1-234-567-8901 ext1234 1 (234) 567-8901 1.234.567.8901 1/234/567/8901 12345678901 I'll answer with my current attempt, but I'm hoping somebody has something better and/or more elegant.", "Asynchronous shell exec in PHP", "Show all of my question/answers to me even if they are deleted", "Take the following C# class: c1 { event EventHandler someEvent; } If there are a lot of subscriptions to c1's someEvent event and I want to clear them all, what is the best way to achieve this? Also consider that subscriptions to this event could be/are lambdas/anonymous delegates. Currently my solution is to add a ResetSubscriptions() method to c1 that sets someEvent to null. I don't know if this has any unseen consequences.", "I'm a newbie in WordPress. I'm trying to understand how it generates the XHTML pages. I guess it's the function of do_action( 'hook-name' ) , but I'm stuck with the understanding of the instruction isset( $wp_filter['all] ) when reading the function do_action because I don't understand what is the meaning of the word all. Is it a PHP feature or a WordPress one?", "If you have a single atom in a box, what state of matter would it be in? If the walls of the box were made of a completely inert material, what state of matter would the atom be in? Or would it not have one? I realized this is a duplicate of several other questions." ]

[ "How many ways are there to distribute 5 distinguishable balls between 3 kids such that each of them gets at least one ball? My approach is $ \\binom{5}{3} 3! $ + $ \\binom{2}{2} \\binom{3}{2}2!$ which is equal to $66$?", "From Geneva airport to Lausanne station", "When, if ever, should voting override answer acceptance for answer sorting?", "Do we need a global test before post hoc tests?", "Including the interaction but not the main effects in a model Is it ever valid to include a two-way interaction in a model without including the main effects? What if your hypothesis is only about the interaction, do you still need to include the main effects?", "Flirtatious Primes Here's a possibly interesting prime puzzle. Call a prime $p$ flirtatious if the sum of its digits is also prime. Are there finitely many flirtatious primes, or infinitely many?", "How to correctly add a path to PATH?", "Finding $\\int^{\\infty}_{0}\\frac{\\ln^2(x)}{(1-x^2)^2} dx$", "Theorem numbering", "Are \"pushforward\" and \"pullback by zero section\" of diffrentials isomorphic in elliptic curves? Let S be a scheme, $p:E\\rightarrow S$ be an elliptic curve with zero section $e:S\\rightarrow E$. My question is: Are $p_*(\\Omega_{E/S}^1)$ and $e^*(\\Omega_{E/S}^1)$ isomorphic? I think it's right because I saw both definitions in different notes and they seem to represent the same thing. Thank you!", "Why did Harime Nui's eye not heal?", "How will old M42 lenses work on a Nikon camera?", "Non-principal ideal in $K[x,y]$?", "How were bullets able to dent Captain America's Shield? Just after Captain America's shield was introduced in Captain America: The First Avenger, Peggy Carter shot few bullets at it which created few minor distortions on it. From page of Marvel.Wikia, Proto-Adamantium This is the original Adamantium created by Dr. MacLain. Proto-Adamantium is the official name for the metal that makes up Captain America's Shield. It has never been recreated and is the absolute most invulnerable item in all of existence. From page of Marvel.Wikia: The true shield was once slightly dented by an enraged Odinforce empowered Thor, using Mjolnir, but he later reconciled and pounded out the small dent. How were few bullets able to dent Captain America's shield then?", "Markov's paper on insolubility of the homeorphy problem I am looking for an English translation of Markov's 1958 paper, On insolubility of the homeorphy problem, which I remember coming across on a website for a computational topology course (taught by Afra Zomorodian).", "Word for phrases that are examples of what they describe", "I mostly use Java and generics are relatively new. I keep reading that Java made the wrong decision or that .NET has better implementations etc. etc. So, what are the main differences between C++, C#, Java in generics? Pros/cons of each?", "Input 0 echo foo | xargs -L 1 -I '{}' echo '{}' Output 0 foo Input 1 echo foo | xargs -I '{}' -L 1 echo '{}' Output 1 {} foo Why changing the order of options of xargs changes the output? Version: xargs (GNU findutils) 4.6.0", "It's said that if is spared in quest, he remains in the Dawnstar sanctuary and can be later hired as a follower. Well I did just that and I can't find him anywhere. Where exactly is he? Does he disappear and only reappear after some other moment in the game?", "How does the Doctor know how old he is? I've often wondered, how does the Doctor know how old he is? He not only travels through time, but also through space, and visits planets where days can be shorter or longer than 24 hours. How does he 'keep score'? Also, does he count his age in Earth years or Gallifrey years? They might be completely different in length." ]

[ "Are nested functions a bad thing in gcc ?", "Traveling Amsterdam-Brussels with KLM ticket on Thalys - When / where does my ticket get stamped?", "Let $a_n=\\sqrt[n]n-1$. Does $\\sum_{n=1}^\\infty a_n$ converge?", "How to show a binomial random variable dominates another binomial random variable with a smaller success value? Let $X\\sim B(n,p_h)$ and $Y\\sim B(n,p_\\ell)$ be two random variables following a respective binomial distribution, where $p_h&gt;p_\\ell$. I want to show that $$P(X\\ge\\alpha)\\ge P(Y\\ge\\alpha),$$ for any $\\alpha\\in\\{0,1,\\dots,n\\}$. In other words, I want to show $$P(X\\ge\\alpha)=\\sum_{i=\\alpha}^{n}\\binom{n}{i}p_h^i(1-p_h)^{n-i}\\ge P(Y\\ge\\alpha)=\\sum_{i=\\alpha}^{n}\\binom{n}{i}p_\\ell^i(1-p_\\ell)^{n-i}.$$ The statement to be proven is obviously true, but proving it is extremely difficult (at least for me). Can anyone give me some guidance on proving it? It would be nice if someone can give an algebraic proof too, that is, show that $$\\sum_{i=\\alpha}^{n}\\binom{n}{i}p_h^i(1-p_h)^{n-i}\\ge \\sum_{i=\\alpha}^{n}\\binom{n}{i}p_\\ell^i(1-p_\\ell)^{n-i}.$$ Thank you very much!", "I've come across a small issue which occurs when a question has been closed but the question itself or one of its answers are being edited. Steps to reproduce: Visit a closed question. (even closed years ago) In a different tab or browser, edit the question or one of its answers. \"an edit has been made to this post; click to load\" message will appear above the edited post in the first tab/browser, click it. The .question-status div becomes hidden, which includes the closed notice below a question and, for a duplicate-closed question, the list of duplicates above the question body. This gives the appearance that the question is no longer closed (until you refresh). Some screenshots: I know it isn't common/important but it did confuse me when looking at a particularly bad question - I thought it had been reopened. Is this an intentional feature? If so, what was the thinking behind it? Another example Before After", "I'm using custom post types, but they don't appear on tag pages along with regular posts and i'd like to include both standard and custom post types on tag or category pages. What would be required before the loop to include all posts? (including custom type). Updated: To add, I found this code , which worked perfectly for the first part: add_filter('pre_get_posts', 'query_post_type'); function query_post_type($query) { if ( is_category() || is_tag() &amp;&amp; empty( $query-&gt;query_vars['suppress_filters'] ) ) { $post_type = get_query_var('post_type'); if($post_type) $post_type = $post_type; else $post_type = array('post','cpt'); // replace cpt to your custom post type $query-&gt;set('post_type',$post_type); return $query; } } Second question still remains though: Is there a way to allow readers to filter by post type? So either of the following would work.. example.com/tag/blue?post_type=custom example.com/tag/blue?post_type=post", "How do I resolve \"WILL_NOT_PERFORM\" MS AD reply when trying to change password in scala w/ the unboundid LDAP SDK?", "How do I do Combinatorics / Counting? If someone could give answers and explain, it would be greatly appreciated. Help required studying for a final. One hundred tickets, numbered 1,2,3,…,100, are sold to 100 different people for a drawing. Four different prizes are awarded, including a grand prize (a trip to Tahiti). A) How many ways are there to award the prizes? B) How many ways are there to award the prizes if the person holding ticket 47 wins the grand prize? C) How many ways are there to award the prizes if the person holding ticket 47 wins one of the prizes? D) How many ways are there to award the prizes if the person holding ticket 47 does not win a prize? E) How many ways are there to award the prizes if the people holding tickets 19 and 47 both win prizes? F) How many ways are there to award the prizes if the people holding tickets 19, 47, 73, and 97 all win prizes? G) How many ways are there to award the prizes if none of the people holding tickets 19, 47, 73, and 97 wins a prize? H) How many ways are there to award the prizes if the grand prize winner is a person holding ticket 18, 47, 73, or 97? I) How many ways are there to award the prizes if the people holding tickets 19 and 47 win prizes, but the people holding tickets 73 and 97 do not win prizes?", "Forgotten PostgreSQL Windows password", "I have recently found an argument against disabling a root user login in Linux at I assume that, if everybody uses a public key authentication, there's no risk at losing the root password. Is it always better to disable the root login via ssh?", "Is there a way to disable WAC String for a specific link (ex. Tracking Link) with AMPscript or otherwise?", "Hydrostatic pressure - doesn't density vary with depth? Our class is learning about hydrostatic water pressure and we have been told that we can calculate the force of the liquid on an object at any depth using \"the density x 9.8 x the depth\". However, as the depth increases, wouldn't the density of the liquid increase because of the weight of the liquid above it compressing it? So should't there be something in the equation to account for the varying density? To me, \"density x 9.8 x depth\" seems like it is saying that the density will be constant...", "Some of code I read in trigger is like this for(account a: [select id from account where id in: mapAccount.keySet()]) { //code } some are like List&lt;Account&gt; listAccount = [select id from account where id in: mapAccount.keySet()]; for(Account a: listAccount ){ //coode } Are those same from performance view?which one is better?", "Random spawn location despite sleeping in a bed I am trying to make Minecraft harder, and one of the ways I wish to do this is to have a \"pseudo-hardcore\" mode where dying spawns you in a random location rather than completely locking you out of the world. I intend to do this by setting the spawn radius to be very high. However, I also want to make this \"bed-proof\" - that is, if someone places a bed and sleeps in it, I want the player to still be spawned in a random location, regardless of their personal spawn point. How do I do this? Command blocks are fine, but data packs are not preferred.", "Which punctuation is correct in this case (colon, semicolon, or period)?", "Restrictive vs Non-restrictive Relative Clause", "Cannot remove any bluetooth device", "Interview: How to ensure that a thread runs after another?", "How can I change (or remove / reset ) my name on a site in Stack Exchange network?", "Here $n$ belongs to natural numbers. Firstly, I proved the relation by putting $n = 1$ . Then, taking $$|\\sin(mx)| \\leq m|\\sin x|$$ true, I had to prove $$|\\sin(m + 1)x| \\leq (m + 1)|\\sin x|$$ Now, here I got stuck. How to prove it?? Please help." ]

[ "In the Harry Potter series, are wizards capable of creating their own spells, or are they limited to the spells that they're taught/learn? I seem to remember something about Snape creating sectumsempra, but I'm not sure if that really is the case.", "So this has been an on-going saga the last few days, and I've already posted several related questions here, and I am feeling quite defeated. I have/had a beautiful 16\" cast iron dutch oven from Cabelas. I took it out for a test spin the other night (I had completed all seasoning steps that the Google Gods recommended). Then: I tried (and failed spectacularly) to cook a pork roast in it, but cooked it at way too hot a temperature and burned/charred/fused the animal fats/juices into the oven, whereby it basically baked into the cast iron (related question ) I tried cleaning/scrubbing it with coarse-grained salt -> did nothing Then I tried cleaning it with dishwashing liquid + salt -> did nothing Then I let the whole thing soak in a vat of a 50/50 mixture of water + white vinegar -> took all the tarry slude off, stripped some seasoning off (revealing bare iron), but in 80% of the burned/charred areas, still did nothing Then I went to town on it with a steel wool and salt and dishwashing liquid and was left with some smooth, properly seasoned surfaces, and some more areas stripped down to bare metal I decided to just re-season it. So I scrubbed it one last time (about 1 hour ago) with a steel wool and some water, got all the rust and remaining crud off (finally), and built a fire. I placed it on the hot coals of the fire and let it sit there for 15 mins. My intention (whether misled or not) was to burn off all the remaining water from when I had previously washed/scrubbed it, then let it cool off, then season it with oil, and then bake it for a few hours. So I just took the oven off the fire and opened the lid...and the entire inside is covered in rust. An hour ago there was none. When I put the oven into the fire 15 mins prior, there had been none (yes, I checked) This just came out of nowhere. I'm ready to give up, unless anyone can offer some concrete set of steps for me that will salvage this $100 rust bucket. How can I get rid of the rust and then re-season this before more rust sets in? Meh...", "When transiting between two flights, will my luggage be automatically transferred?", "Assigning strings to arrays of characters I am a little surprised by the following. Example 1: char s[100] = \"abcd\"; // declare and initialize - WORKS Example 2: char s[100]; // declare s = \"hello\"; // initalize - DOESN'T WORK ('lvalue required' error) I'm wondering why the second approach doesn't work. It seems natural that it should (it works with other data types)? Could someone explain me the logic behind this?", "How many \"Recommend Close\" votes is too many?", "90s (or earlier) Japanese anime movie: two planets at war, young man is in love with princess from the other planet, and floods his own village I would like to find out the title of a Japanese anime feature film (not a series) that I saw on Romanian TV in the early 90s. It was about a feud between the peoples of two planets (one very technologically advanced, the other not). The two planets go to war against each other, and a young man from one of the planets falls in love with a princess from the other planet. I recall a scene where the army of the second planet take off in hot air balloons when they go to war. The only other thing I recall is that there is a dam next to the village where the young man lives, and for some reason he opens the dam gates and floods his own village. I do not recall there being robots in the movie, however I remember very vaguely that the technology level was probably at the level of late 19th century Europe on one planet and pre-industrial on the other one. What it's not: Nobunaga the Fool Aldnoah Zero Queen Millennia Uchuu Senkan Yamato (movie)", "Is $n^{th}$ root of $2$ an irrational number? Possible Duplicate: Will every $n^{th}$ root of $2$ be an irrational number? If yes, how can I prove that?", "My account has 20 (!) sites associated to it. I only use it for 3-5 sites. To reduce clutter, I would like to delete my profiles that I do not use much. I have went through , but when I enter the profile URL as: http://russian.stackexchange.com/users/5772/alex it gives the error message: oops! this isn't a link to a valid profile What procedure do I go through to delete my profile only on certain sites?", "How do we control web page caching, across all browsers?", "The derivation of the Hamilton-Jacobi equation using canonical transformations is typically done involving a type-2 generating function. Is it possible to use a another type of generating function, namely type 1, 3 or 4?", "How many points in RSA, such that $m^e = m \\bmod n$ For every RSA-cryptosystem, there exist some messages $m$, for which it holds that $m^e \\equiv m \\pmod n$ As to the question, how many such messages exist, this question has already been asked and answered here: However, I do only understand the answer up to a certain point Suppose that $n$ is only 1 prime. Then it holds that the number of unconcealable messages is $\\gcd(e-1, p-1)+1$ This is because in $m^e \\equiv m \\pmod p$ , either $m = 0$ or $m \\not= 0$. In the latter case $m$ can be expressed as $g^t$, where $g$ is a Generator in $\\mathbb{Z_p}$ $g^{t*e} \\equiv g^t \\pmod p$ $g^{t(e-1) \\bmod p -1 } \\equiv g^{0 \\bmod p -1} \\pmod p$ $t(e-1) \\equiv 0 \\pmod {p-1} $ has exactly $\\gcd(e-1, p-1)$ solutions, so the total number of unconcealable messages is, together with $m=0$ , $\\gcd(e-1, p-1)+1$ When we now look at real RSA, which has two prime factors in its modulus, it holds that the number of unconcealable messages is $(\\gcd(e-1, p-1)+1)\\cdot(\\gcd(e-1, q-1)+1)$ Why is that so? I suppose it has to do with CRT, but I just cant understand why.", "Single Variable Calculus Reference Recommendations This question is a of the common question asking for calculus references. It is here to away the repetition, and give a canonical resource for calculus references. I'm looking for a resources to learn single-variable calculus.", "Why is it important to apply transformation to an objects data? I've watched several tutorials and very often they applied the location, rotation or scale to the object when they transformed it in Object Mode. They always said it is important, but why?", "I'm testing something in Oracle and populated a table with some sample data, but in the process I accidentally loaded duplicate records, so now I can't create a primary key using some of the columns. How can I delete all duplicate rows and leave only one of them?", "I am curious if it is possible to have a VPS that has data on it that is not readable by the hosting provider, but is still usable on the VPS. Obviously there are some things that you could do to prevent them from reading anything... You could change all the passwords, including root. But then, they could still use some alternate boot to reset the password, or they could just mount the disk another way. So, you could encrypt the disk or at least some of the contents on the disk. But then it seems that if you decrypted the content, they could still \"peer in\" to see what you were doing at the console, because after all, the virtualization platform should allow this. And even if you could stop that, it seems they could just read the RAM of the VPS directly. Of course, the VPS can store data on it and as long as the key is not on the VPS and the data is never decrypted there, then the host cannot get the data. But it seems to me that if any point the data on the VPS is decrypted...for use on the VPS...then the hosting provider can get the data. So, my two questions are: Is this correct? Is it true that there is no way to 100% secure data on a VPS from a host from seeing it, while keeping it accessable by the VPS? If it is possible to make it 100% secure, then how? If it is not possible, then what is the closest you can get to hiding data from the web host?", "What is the difference between \"var=${var:-word}\" and \"var=${var:=word}\"?", "Difference between least squares and minimum norm solution Consider a linear system of equations $Ax = b$. If the system is overdetermined, the least squares (approximate) solution minimizes $||b - Ax||^2$. Some source sources also mention $||b - Ax||$. If the system is underdetermined one can calculate the minimum norm solution. But it does also minimize $||b - Ax||$, or am I wrong? But if least squares is also a minimum norm, what is the difference, or the rationale of the different naming?", "Should we have a tag for significant points in time? There are many discussions about the current incidence. For example: Should we have a whole tag for this incidence? In general, if in the future there are more crises and incidences like this, should they have their own tags too? I feel it's fine, as we have specific tags for individual events like . And, should we have a tag? Related: Note that these questions are specifically about the conflict 2019, while this question is simply about creating meta tags for significant events.", "Can anyone help me identify a story about kids with silver blood?", "Formatting doubles for output in C#" ]

[ "Top-bar hat misplaced", "What command can I type into the Terminal so that I can delete all .svn folders within a folder (and from all subdirectories) but not delete anything else?", "I have a background in QFT, GR and differential geometry at the level of a master student in theoretical physics. I would like to touch the area of CFT. I know the textbook of Philippe Di Francesco. It may be too big for the beginner like me. Are there some good introductory lectures or textbooks adapted to the needs of beginners?", "Two \"offtopic\" flag reasons", "How to get a cross-origin resource sharing (CORS) post request working", "I have a Git repo that I have deleted four files from using rm (not git rm), and my Git status looks like this: # deleted: file1.txt # deleted: file2.txt # deleted: file3.txt # deleted: file4.txt How do I remove these files from Git without having to manually go through and add each file like this: git rm file1 file2 file3 file4 Ideally, I'm looking for something that works in the same way that git add . does, if that's possible.", "How to disable notifications for a single mailbox in Mail? When managing multiple mailboxes, is it possible to disable the notifications for certain mailboxes?", "Workflow for converting LaTeX into Open Office / MS Word Format", "Windows 98 on a modern computer?", "As a(n) noun vs as only", "Why do C# multidimensional arrays not implement IEnumerable?", "How do I get \"restart\" option in the shutdown menu in Unity? The dropdown menu I get when I click on the gear link in the top right corner only shows these options: Lock Computer Logout Suspend Hibernate Shutdown There is no \"restart\" or \"reboot\". How can I make that option available? Bonus question: Can I remove Hibernate, Lock, and Suspend?", "Find a formula for Taylor series of $\\left(\\frac{1}{1+z^2}\\right)^n$ So the way I think I should approach this is by getting a result for $n=1,2,3...$ and then examine them. I could easily get the Taylor series expansion for $n=1$, but then I don't really know how to proceed, because I can't always break down a power of a polynomial. And a power of a summation doesn't seem as a legit answer either. Can anyone help? Thanks", "How do I solve the partial differential equaiton $u_{t} = (u_{x})^{-1}$ subject to the conditions $u(t,x) \\geq 0$ and $u(0,0) = $0. Use the separation Ansatz $u(t,x) = f(t)g(x)$. The inverse in confusing me", "Separate long math text under sum symbol into different lines?", "Fonts larger than \\Huge? How can I make text that is larger than the size of the output of {\\Huge ...}? I would like to be able to make text arbitrarily large (even if that is done by some suboptimal scaling routine).", "Has it been practically proven that quantum superposition exists ? If yes, how does it even work?", "Let $G$ a group with normal subgroups $M,N$ such that $M\\cap N=\\{e\\}$. Show that if $G$ is generated by $M\\cup N$ then $G\\cong M \\times N$.", "Possible Duplicate: I have recently seen this image: Should \"a\" have been used instead of \"an\" in the \"...an $100,000 apartment\" part?", "Computing: $\\int_0^1 \\sqrt[3]{x\\log{\\frac{1}x}} \\, \\mathrm dx$" ]

[ "International TLD's vs. duplicate content I currently work at a pretty big website that has visitors from around the globe. My job is to help out on the SEO, and one thing we've been discussing lately is the use of international TLD's. The ones we use range between: (partly) translated websites like .es and .de that serve most of the content in the country's language non-translated (english) websites for non-english languages (due to a lack of translations) like .ro and .cz english websites for english speaking countries with localized TLD's (.co.nz, .co.uk) On one hand I really have the feeling this is causing a lot of duplicate content, especially for the last two categories of TLD's. On the other hand though it seems a lot like country-specific TLD's tend to score a lot better in that country's Google. Would it be advisable to keep on using these domains, or should we canonicalize them all to the .com version?", "How to make 7-zip do a whole bunch of folders I got a bunch of pictures that I had to crop into 800x600 pixels. That was easily done, but now I have to upload them so the family can see them all. Thing is, this is 500MB in pictures. I decided to simply zip the separate folders, which each contain an almost equal amount of pictures. This way I can upload a couple each day. Doing this manually is a very long and hard job. I wonder if there is a way to make 7-zip handle each folder individually? I think I'll need a batch file to do it, but I'm not good with that. I've put everything under one folder. In the various subfolders is where the pictures are located. What I need is for the contents of that folder to be zipped. I'm not sure if I can just zip the folder along with it. I know PHP has a zip module, I've just never worked with it, so I'm not sure whether it can handle the fact that the content of the zip is a folder which contains the items, instead of just the items.", "This is almost a duplicate of the following questions (but, read further): But, I wasn't able to apply the proof to my case of a group of order 10 and an element of order 5. In my case, if I try a proof by contradiction, I'm left with the fact that every element in $G$ is of order 2, but if I divide them into subgroups, every subgroup is of order 2, and has one unique element. I also tried other methods to prove the theorem, but couldn't come up with anything meaningful. I'm a beginner in the field, and am not familiar with theorems such as Cauchy's or Sylow's theorem (I'm aware of Lagrange's theorem). Therefore, please try to provide a simple answer, thanks!", "Flag indicator present on Meta, but no flags visible It looks as if the 10k-tools flagged post list is b0rken. Next to the review link in the toolbar there is a flag counter showing there are 10 flags to be reviewed: Clicking on that flag counter leads to an empty page: The moment I visit that page (through clicking on the flags counter, or by going to the review queue first then clicking on Tools, selecting the flags tab if not already selected), the flags counter disappears from the toolbar: but after a while (half an hour, an hour?) the flag count re-appears in the toolbar. Either the counter is wrong (presumably taken from a Redis cache somewhere) or the 10k flag review page is falling over every time someone tries to load it. This at first appeared to happen only on Meta, on Stack Overflow the flags page has plenty to review. However, there are now on Stack Overflow.", "What does a program do when it's sent SIGKILL signal? When I used killall -9 name to kill a program, the state become zombie. Some minutes later, it stopped really. So, what's happening during those minutes?", "Bash: Syntax Error on @()", "Why does 1366x768 resolution exist? I know that there's but it doesn't have any real answers despite having been viewed 12,400 times, and the fact that it's been closed. With that in mind... Why in the world is 1366x768 resolution a real thing? It has an aspect ratio of 683:384, which is the weirdest thing I've ever heard of while living in a 16:9 world. All screens and resolutions I've been familiar with have been 16:9 aspect ratio. My screen, 1920x1080, is 16:9. The 720p that I'm familiar with is 1280x720, also 16:9. 4K that I'm familiar with, 3840x2160, is also 16:9. Yet 1366x768 is 683:384, a seemingly wild break from the standard. I know there are plenty of other resolutions all over the place, but 1366x768 seems to dominate most of the mid priced laptop world and also seems unique to the laptop world. Why don't laptops use 1280x720 or something else as a standard?", "Problem with \\mkbibdateapalongextra of biblatex-apa biblatex-apa gives me this: ! Undefined control sequence. &lt;argument&gt; \\mkbibdateapalongextra {labelyear}{labelmonth}{labelday}\\iffieldu... I'm using the default (english) language, and have done the: \\DeclareLanguageMapping{norsk}{norsk-apa} \\DeclareLanguageMapping{english}{american-apa} thing. Here's a short example: \\documentclass[english]{memoir} \\usepackage{babel} \\usepackage{roffe} \\usepackage[backend=biber,date=short,maxcitenames=2,style=apa]{biblatex} \\DeclareLanguageMapping{norsk}{norsk-apa} \\DeclareLanguageMapping{english}{american-apa} \\addbibresource{Papers2.bib} \\addbibresource{R.bib} \\begin{document} \\cite{R-base} \\printbibliography \\end{document} This one replicates the problem.", "Note: This is not the same as , which is about the moderator tool. I am talking about the flag history page that is accessible through the user profile at . I tend to have a pretty good hit rate for flags, well above 90% helpful on several sites. I also semi-regularly review the flag history page, both to see the status of any outstanding flags as well as see how flags I raised have been handled. Particularly, whenever a flag of mine is declined, I look over the post I raised the flag against with this new information in mind, to try to determine if I should change my flagging behavior in some way to better match the specific site's scope. However, comment flags are difficult in this regard. Most often, there is only a binary status: helpful or declined. Helpful comment flags nearly always lead to the comment being deleted, so that obviously could present a bit of a problem, but that's not really relevant because a helpful flag means you should just keep doing what you've been doing. Declined comment flags, on the other hand, usually mean the comment is kept. It's the declined comment flags that I want to learn more about. But there's no way to! All the flag says is which post it was on, how I flagged a comment, that I was the one to raise the flag (which frankly is rather useless information when you are already looking at your own flags summary), when the flag was raised and whether it's pending, helpful or declined. In a very few cases the moderator handling the flag may leave a helpful return comment. This can get even more confusing if I raise multiple flags in quick succession against comments on the same question including any answers to it, because they basically all get bundled together. Even in the case of a declined flag where the comment remains, there is no way to find your way back to the specific comment you flagged! Thus it is very difficult to recognize the error of your ways. Because comment flags (with few exceptions) are handled by diamond moderators only, the lack of feedback about which comment's flag was declined means it's easy to keep wasting the moderators' time without even intending to do so. Hence my feature request: add a link to the specific comment that the specific flag was raised against, ideally only if that comment remains.", "Is there an idiom for someone who gets what he deserved? Like someone receiving punishment for his evil deeds or someone getting awarded for his good deeds?", "Appreciate your wisdom on this, My understanding is most of the tutorials recommend normalizing / scaling the data prior feeding the tensorflow models. Doesn't normalization require that data conforms to the normal parametric distribution? What good is a non-linear model if scaling / normalizing is a pre-requisite prior using the non-linear model such as tensorflow? So back to the question, should I always normalize / scale my data prior feeding my tensorflow models? thanks", "Quickest way to rename files, without retyping directory path", "First of all, I know that light does indeed travel slower in a medium like air or water, but that's because the photons are bouncing off of the medium's particles and in different directions so the light beam as a whole is slowed down (or at least that's the classical explanation I've read somewhere). But my question is about light traveling freely in the vacuum. What if an astronaut during a spacewalk switches on a flashlight towards the opposite direction he is moving. Will that light travel slower than normal? If not, is there another way to make light move slower? For example, can you make a beam of light move so slow that you can visually perceive it being affected by gravity?", "How can you quickly get the complete path to a file for use in terminal?", "Are there any expressions that describe going from a bad to a worse situation? Are there idioms or expressions in English that describe going from one bad situation to one that's even worse? I heard \"between a rock and hard place\" but this describes a dilemma not really a transition. I am looking for an expression that describes someone trying to get out of a bad situation but after much effort, the situation only got worse.", "Do we actually get more sick (flu/cold) during winter? The word flu derives from the Italian phrase \"influenza de freddo\" meaning \"influence of the cold\". Indeed it is that time of the year when my colleagues seem to have the flu/cold more often than not. I remember during university, winter lectures would be riddled with people coughing and sneezing - the so called \"freshers flu\" Questions Is there statistical evidence for this claim? If so, what are the causes/factors involved? asks why our noses get runnier during cold whether, is this related?", "Proving that $A_n$ is the only proper nontrivial normal subgroup of $S_n$, $n\\geq 5$ There is a famous Theorem telling that: For $n≥5$, $A_n$ is the only proper nontrivial normal subgroup of $S_n$. For the proof, we firstly start with assuming a subgroup of $S_n$ which $1≠N⊲S_n$. We proceed until at the last part of proof's body, we assume $N∩A_n=\\{1\\}$. This assumption should be meet a contradiction with normality of $N$ in $S_n$. There; we get $N=\\{1,\\pi $} in which $\\pi$ is an odd permutation of order $2$. Now for meeting desire inconsistency, I have two approaches: (a) Since every normal subgroup, having two elements, lies in the center of $G$ so, our $N⊆ Z(S_n)=\\{1\\}$ for $n≥5$ and then $N=\\{1\\}$. (b) Clearly, $1≠N$ acting on set $\\Omega=\\{1,2,...,n\\}$ is intransitive wherein $|\\Omega|≥5$ and according to the following Proposition $S_n$ would be imprimitive. Proposition 7.1: If the transitive group $G$ contains an intransitive normal subgroup different from $1$, then $G$ is imprimitive (Finite Permutation Groups by H.Wielandt). May I ask if the second approach is valid? I am fond of knowing new approach if exists. Thanks.", "pgfplots: lines and markers in different colors With pgfplots, I am creating a simple coordinate plot with error bars like this: \\documentclass[crop,10pt]{standalone} \\usepackage[english]{babel} \\usepackage{pgfplots} \\begin{document}% \\setlength{\\linewidth}{246pt}% \\begin{tikzpicture} \\begin{axis}[ width=\\linewidth, ytick pos = left, xtick pos = left, clip=false, axis on top, tick align = outside, yticklabel style={% /pgf/number format/fixed, /pgf/number format/precision=1, /pgf/number format/fixed zerofill }, ytick scale label code/.code={}, xlabel={X}, ylabel={Y}, ] \\addplot[mark=*] plot[ error bars/.cd, y dir=both, y fixed=0.0001 ] coordinates{(1,0.0005) (1.1,0.0013) (5,0.0015)}; \\end{axis} \\end{tikzpicture} \\end{document} In the original plot I have a lot more points. I would now like the line and the markers (including the error bars) to have different colors to better distinguish the line from the error bars. Is that somehow possible? The only way I found so far is to plot the data just as a line in one color and then plot it again just as markers in another color. This works, but I guess there must be some better solution to this. Thanks for the support, John", "About 'start' and 'begin' Are 'begin' and 'start' interchangeable? Both &quot;This is a new start&quot; and &quot;This is a new beginning&quot; work, right? Then during games, they say &quot;Let's start&quot;, but I never heard &quot;Let's begin&quot;. So is there supposed to be a difference? And then one guy said this &quot;They could not begin to start a conversation&quot;. What is this supposed to mean? Is it correct?", "Product of square of distances from vertices of a polygon of radius a I want to find out the following product. $\\prod_0^{n-1} (r^2 + a^2 -2ra\\cos(2k\\pi/n - \\theta))$ I have been trying to use complex numbers but did not work out. The book I am reading the result is directly stated as $r^{2n} + a^{2n} -2r^na^n\\cos(\\theta)$. Please help." ]

[ "How do I add a non-deformed end cap to a tube? I want to create some parts that I can reuse for models. I was trying to make a steam punkish exhaust pipe. I want to be able to make the pipe of any length, and as curvy as I like but I want to keep the end cap always undeformed. I approximated my results by hand placing the \"crown\" at the end of this bezier curve. I tried to make an array modifier that included the crown as the end cap, but that results in the end cap deforming.", "Impossibility of constructing a continuum-size linearly independent set in $\\Bbb R$ This is a response to the following exchange at [Bill constructs a $\\aleph_0$ linearly independent set in $\\Bbb R$] Can you extend the idea of this proof to get the right dimension? Currently, you only have a countably infinite independent set, but the dimension is size continuum. – I believe the answer to this question is no, for the following reason. Suppose we have a spanning set for $\\Bbb R$ over $\\Bbb Q$, of cardinality $\\frak n$. Then by definition we have the cardinality equation ${\\frak c}\\le^*[{\\frak n}]^{&lt;\\omega}\\cdot \\aleph_0$ (where $[{\\frak n}]^{&lt;\\omega}$ is the cardinality of finite subsets, and $\\frak m\\le^*n$ means there is a surjection from $\\frak n$ to $\\frak m$). If $\\frak n$ is finite, then we get ${\\frak c}\\le^*\\aleph_0$ which is false, so $\\frak n$ is infinite (but not necessarily Dedekind-infinite). If we assume the axiom of choice, then the equation reduces to $\\frak c\\le n$, hence every Hamel basis is size continuum. But without AC I don't know any way to simplify the original equation to get anything stronger than &quot;$\\frak n$ is infinite&quot;. This is at best heuristic evidence for the original question, since it is considering a different problem (spanning sets instead of linearly independent sets). How could one show that there are no ZF-constructible $\\Bbb Q$-linearly independent subsets of $\\Bbb R$ of cardinality continuum?", "is it true if $f,\\overline f$ are both analytic in a domain $\\Omega$ then $f$ is constant? I am not able to find out what property of holomorphic map I need to apply. please help.Thank you. $f(z)=u(x,y)+iv(x,y)$, $\\bar{f}(z)=u(x,y)-iv(x,y)$", "I just came onto a project with a pretty huge code base. I'm mostly dealing with C++ and a lot of the code they write uses double negation for their boolean logic. if (!!variable &amp;&amp; (!!api.lookup(\"some-string\"))) { do_some_stuff(); } I know these guys are intelligent programmers, it's obvious they aren't doing this by accident. I'm no seasoned C++ expert, my only guess at why they are doing this is that they want to make absolutely positive that the value being evaluated is the actual boolean representation. So they negate it, then negate that again to get it back to its actual boolean value. Is this correct, or am I missing something?", "In statistical learning, implicitly or explicitly, one always assumes that the training set $\\mathcal{D} = \\{ \\bf {X}, \\bf{y} \\}$ is composed of $N$ input/response tuples $({\\bf{X}}_i,y_i)$ that are independently drawn from the same joint distribution $\\mathbb{P}({\\bf{X}},y)$ with $$ p({\\bf{X}},y) = p( y \\vert {\\bf{X}}) p({\\bf{X}}) $$ and $p( y \\vert {\\bf{X}})$ the relationship we are trying to capture through a particular learning algorithm. Mathematically, this i.i.d. assumption writes: \\begin{gather} ({\\bf{X}}_i,y_i) \\sim \\mathbb{P}({\\bf{X}},y), \\forall i=1,...,N \\\\ ({\\bf{X}}_i,y_i) \\text{ independent of } ({\\bf{X}}_j,y_j), \\forall i \\ne j \\in \\{1,...,N\\} \\end{gather} I think we can all agree that this assumption is rarely satisfied in practice, see this related and the wise comments of @Glen_b and @Luca. My question is therefore: Where exactly does the i.i.d. assumption becomes critical in practice? [Context] I'm asking this because I can think of many situations where such a stringent assumption is not needed to train a certain model (e.g. linear regression methods), or at least one can work around the i.i.d. assumption and obtain robust results. Actually the results will usually stay the same, it is rather the inferences that one can draw that will change (e.g. heteroskedasticity and autocorrelation consistent HAC estimators in linear regression: the idea is to re-use the good old OLS regression weights but to adapt the finite-sample behaviour of the OLS estimator to account for the violation of the Gauss-Markov assumptions). My guess is therefore that the i.i.d. assumption is required not to be able to train a particular learning algorithm, but rather to guarantee that techniques such as cross-validation can indeed be used to infer a reliable measure of the model's capability of generalising well, which is the only thing we are interested in at the end of the day in statistical learning because it shows that we can indeed learn from the data. Intuitively, I can indeed understand that using cross-validation on dependent data could be optimistically biased (as illustrated/explained in ). For me i.i.d. has thus nothing to do with training a particular model but everything to do with that model's generalisability. This seems to agree with a paper I found by Huan Xu et al, see \"Robustness and Generalizability for Markovian Samples\" . Would you agree with that? [Example] If this can help the discussion, consider the problem of using the LASSO algorithm to perform a smart selection amongst $P$ features given $N$ training samples $({\\bf{X}}_i,y_i)$ with $\\forall i=1,...,N$ $$ {\\bf{X}}_i=[X_{i1},...,X_{iP}] $$ We can further assume that: The inputs ${\\bf{X}}_i$ are dependent hence leading to a violation of the i.i.d. assumption (e.g. for each feature $j=1,..,P$ we observe a $N$ point time series, hence introducing temporal auto-correlation) The conditional responses $y_i \\vert {\\bf{X}}_i$ are independent. We have $P \\gg N$. In what way(s) does the violation of the i.i.d. assumption can pose problem in that case assuming we plan to determine the LASSO penalisation coefficient $\\lambda$ using a cross-validation approach (on the full data set) + use a nested cross-validation to get a feel for the generalisation error of this learning strategy (we can leave the discussion concerning the inherent pros/cons of the LASSO aside, except if it is useful).", "Prove that, for $p > 3$, $(\\frac 3p) = 1$ when $p \\equiv 1,11 \\pmod{12}$ and $(\\frac 3p) = -1$ when $p \\equiv 5,7 \\pmod{12}$ $(\\frac 3p)$ is the Legendre symbol here, not a fraction, if that wasn't clear. This is what I have so far: We know by Gauss's Lemma that $(\\frac qp) = (-1)^v$ where $$v = \\#\\left\\{1 \\le a \\le \\frac{p-1}{2} \\mid aq \\equiv k_a \\pmod{12}),\\space -p/2 &lt; k_a &lt; 0\\right\\}$$ And we also know that multiples of $(\\dfrac{p-1}{2}) \\times 3$ must be between $0$ and $p/2$, between $p/2$ and $p$, or between $p$ and $3p/2$. Representing $p$ as $12k + r$ seems like the next step, but I'm not sure where to go from there.", "Units and Nilpotents", "So assume $Y$ and $X$ are exponentially distributed with parameters $y_1$, and $x_1$ respecitively. assume c is a constant. I am having huge trouble to understand the integration of the following expression. $P(Y&lt;c/u(X))$ $=\\int_{t}^{\\infty}f_X(x)\\int_{0}^{c/u(x)}f_Y(y)dydx +\\int_{0}^{t}f_X(x)\\int_{c/u(x)}^{\\infty}f_Y(y)dydx$ where t is the cross-point that $u(x)$ change sign here $c/u(x)$ is given by the plot below, t is the point crossing the zero: Confusion: I don't understand the second integration of the second term \"$\\int_{c/u(x)}^{\\infty}f_Y(y)dydx$\", this isn't right because Y an X only defined for y>0, and x>0. So it's the first quadrant in this plot.", "Prove that $\\frac{x_1}{1+x_2+x_3+\\ldots+x_n}+\\frac{x_2}{1+x_1+x_3+\\ldots+x_n}+\\ldots+\\frac{x_n}{1+x_1+x_2+\\ldots+x_{n-1}}\\ge\\frac{n}{2n-1}$. If $x_1,x_2,\\ldots,x_n&gt;0$ and $x_1+x_2+\\ldots+x_n=1$, prove that $$\\frac{x_1}{1+x_2+x_3+\\ldots+x_n} + \\frac{x_2}{1+x_1+x_3+\\ldots+x_n} +\\ldots + \\frac{x_n}{1+x_1+x_2+\\ldots +x_{n-1}} \\ge \\frac {n}{2n-1}$$ This can easily be simplified: $$\\frac{x_1}{2-x_1} + \\frac{x_2}{2-x_2} +\\ldots + \\frac{x_n}{2-x_n} \\ge \\frac {n}{2n-1}$$ I could try using the Cauchy-Schwarz inequality: $$\\frac{x_1}{2-x_1} + \\frac{x_2}{2-x_2} +\\ldots + \\frac{x_n}{2-x_n} = \\frac{x_1^2}{2x_1-x_1^2} + \\frac{x_2^2}{2x_2-x_2^2} +\\ldots + \\frac{x_n^2}{2x_n-x_n^2} \\ge \\frac{(x_1+x_2+\\ldots+x_n)^2}{2(x_1+x_2+\\ldots+x_n)-(x_1^2+x_2^2+\\ldots+x_n^2)}=\\frac{1}{2-(x_1^2+x_2^2+\\ldots+x_n^2)}=\\frac{n}{2n-(x_1^2+x_2^2+\\ldots+x_n^2)n}$$ It's left to prove that $$(x_1^2+x_2^2+\\ldots+x_n^2)n \\ge 1$$ or $$(x_1^2+x_2^2+\\ldots+x_n^2)n=1$$I can continue using the Cauchy-Schwarz inequality again: $$(x_1^2+x_2^2+\\ldots+x_n^2)n=(x_1^2+x_2^2+\\ldots+x_n^2)(1+1+\\ldots+1)\\ge(x_1+x_2+\\ldots+x_n)^2=1$$ So I've proved it myself. (I've shown this proof after editing, I didn't post the question with the solution in the details. I found the proof a while after putting the question here).", "Foreign key constraint on array member? Suppose I have a table containing job roles: CREATE TABLE roles ( \"role\" character varying(80) NOT NULL, CONSTRAINT \"role\" PRIMARY KEY (role) ); Suppose I further have a table, users, and each row (a specific user) can have an arbitrary number of job roles: CREATE TABLE users ( username character varying(12) NOT NULL, roles character varying(80)[] NOT NULL, CONSTRAINT username PRIMARY KEY (username) ); I should probably make sure that each member of users.roles[] exists in roles.role. It seems to me that what I want is a foreign key constraint on each member of users.roles[] such that if references roles.role. This doesn't seem possible with postgres. Am I looking at this the wrong way? What is the suggested \"right\" way to handle this?", "Given $n+1$ points in the plane, Lagrangian interpolation gives the unique polynomial of degree less or equal to $n$. From the examples I've seen so far, interpolation polynomials all have degree exactly $n$ but I don't know if there might be a set of points for which the interpolation gives a polynomial of degree strictly less than $n$. Many thanks for your answers.", "I’m a newbie in Python. I’m learning regexes, but I need help here. Here comes the HTML source: &lt;a href=\"http://www.ptop.se\" target=\"_blank\"&gt;http://www.ptop.se&lt;/a&gt; I’m trying to code a tool that only prints out http://ptop.se. Can you help me please?", "How to install and configure Wine? I am looking for a step by step instruction to guide me in the ways of installing, configuring and debugging many of the issues new users have when dealing with Wine in Ubuntu. What is the recommended way of installing Wine, some of the key issues that it has and how to solve them? If I have a specific problem with an App in Wine, how do I go about solving it? What are the recommended steps to ensure that I can fix a problem related to an app I wish to use?", "How to change password complexity requirements in Ubuntu 14.04LTS", "Resize image proportionally with CSS?", "is there a way to request a new tag be created? Possible Duplicate: I do not have sufficient reputation on any site to create new tags, but I do on occasion find myself in need of a tag that does not exists. Is there a feature that allows for a person with sub-1500 reputation to request a new tag?", "Meaning of symbols $\\vdash$ and $ \\models$ I'm confused about the use of symbols $\\vdash$ and $ \\models$. Reading the answers to and I see that: the turnstile symbol $ \\vdash $ denotes syntactic implication. Then $ S \\vdash \\psi$ means that $\\psi$ can be derived from the formulae in $S$ the double turnstile $ \\models $, denotes semantic implication. Then the notation $A \\models B$ means simply that B is true in every model in which A is true. So I understand that, e.g., $(ZFC+ A) \\vdash B$ means that $A \\Rightarrow B$ is a theorem in ZFC and, in this sense $\\vdash$ is a mathematical symbol for a theorem. While $(ZFC+ A) \\models B$ means that $ B$ is true in every model of ZFC in which $A$ is true, and, in this sense $\\models$ is not a mathematical but a metamathematical symbol. I understand correctly? And those are the only uses of the two symbols?", "Why isn't Google Chrome available in the Software Centre?", "How to resolve conflicting distributions in apt-get When doing an apt-get update/upgrade I see that warning W: Conflicting distribution: https://downloads.plex.tv/repo/deb public InRelease (expected public but got ) I was upgrading to Ubuntu Zesty 17.04 before and do not know how to fix the above. Already have seen ? but there are no suggested fixes for that. Maybe one of you can give some hints? Thanks!", "When certain nationalities of people want to travel in the Schengen zone, they are required to apply for a Schengen visa. This is a straight-forward process for most, but when an applicant has had problems with removals or refusals they may be reluctant to apply because they want to avoid the complexities of serial visa refusals. This reluctance may lead some into wondering how their history can be expunged, and this line of thought inevitably leads to the idea of getting their passport replaced with a new one. This sounds like a great formula for people who have had prior refusals or removals. In essence they can become 'reincarnated' as a first-time traveller and hence avoid the unpleasantness of revealing their prior interactions with the Schengen authorities. The relevant parts of the application form are shown here... Nothing asks about a prior removal or refusal, and the applicant is left with simple denials for 3 questions in order to present themselves as a first-time traveller. Assuming the person is happy to set aside the moral issues associated with denying their history, are there any holes to this strategy? This question is scoped to Schengen visa applications so that it will not be unmanageably broad, but answers from other regimes (particularly the affluent Commonwealth and the USA) are acceptable as long as the main points are relatively consistent with Schengen." ]

[ "What happens if my shield breaks?", "\"Open in terminal\" not working on nautilus as root When using natilus as root, open in terminal used to work as using with any user. However, when I press open in terminal when using nautilus as root now, it does nothing. How to solve it? The error: GLib-GObject-CRITICAL **: g_object_set_data: assertion 'G_IS_OBJECT (object)' failed", "How is Faulhaber's formula derived?", "Eigenvectors of real symmetric matrices are orthogonal", "This question is related to \"The Last Jedi\": The maneuvre that vice admiral Holdo (with the purple hair) uses towards the end of the film seems remarkably effective. It seems that it would have worked pretty well much earlier. Especially as two other ships were just allowed to run out of fuel and be destroyed. It seems doing it earlier with different assets would have incurred less losses. Yet nobody seemed to consider it. Any in universe reason why?", "Using TIPA with fontspec", "Extending the User model with custom fields in Django", "Avoiding \"(Not Responding)\" label in windows while processing lots of data in one lump I occasionally need to process a large amount of data from one package off the network, which takes sufficiently long that when the user tries to interact with the application windows adds the \"(Not Responding)\" string to the window title. I am aware this is because the processing is being done within a call to handle a message (some way up the stack) and therefore is blocking the message pump. I'm also aware the ideal way to deal with this is to process the data asynchronously in a separate thread so the pump can continue running, however this is a LARGE desktop application which is single threaded from top to toe and safely spinning this processing off is not feasible in our time frame. So with that in mind, is there by any chance a way I can at least avoid the \"not responding\" moniker (which to most users reads as \"has crashed\") by telling windows my application is about to be busy before I begin the work? I believe there is something along these lines when responding to a request to close, one can keep asking windows for more time to avoid it proclaiming that your not \"closing in a timely fashion\" I should add this is a C++ MFC application.", "Meaning of probability notations $P(z;d,w)$ and $P(z|d,w)$ What is the difference in meaning between the notation $P(z;d,w)$ and $P(z|d,w)$ which are commonly used in many books and papers?", "is one of those surprisingly clear results of mathematical calculations, for which I am inclined to think that some kind of intuitive understanding should or must be possible. However I don't know of any, do you? *Independence of time $\\leftrightarrow$ energy conservation. *Independence of position $\\leftrightarrow$ momentum conservation. *Independence of direction $\\leftrightarrow$ angular momentum conservation. I know that the mathematics leads in the direction of Lie-algebra and such but I would like to discuss whether this theorem can be understood from a non-mathematical point of view also.", "Show that $a_n=\\sin(n)$ does not converge My idea: Take two subsequences: $a_{n_k}=\\sin(\\frac {\\pi k} 2)$ , $a_{n_l}=\\sin(\\frac {2\\pi l} 3)$ So: $\\forall n$ : $\\lim_{n\\to\\infty} a_{n_k}=1$, $\\lim_{n\\to\\infty} a_{n_l}=-1$ So two inifinite subsequence converge to different limits thus the sequence $a_n$ doesn't converge. Is that correct ? Edit: The contrapositive of the defintion of a limit of a sequence: $\\exists\\epsilon&gt;0 : \\forall n\\in N : \\exists n&gt;N \\Rightarrow |x_n-L|&gt;\\epsilon$ Take $\\epsilon =1$ and we know that $\\sin(n)$ is bounded so lets take it's supermum: 1 $|1-1|&gt;\\epsilon=1\\Rightarrow 0&gt;1 \\Rightarrow$ Contradiction.", "In Korea, we learned that we should use the past tense when the subject is an historical event, as in \"The Korean war broke out in 1950.\" However, I think that when the event continues to affect the present (now), we should use the present perfect. So I think that we can say 'The Korean war has broken out in 1950.' Am I right?", "Does the new guidance on duplicate questions suggest closing a question as duplicate, if the original answers the OP's question? In other words, should we now look at the content of the answers when we are evaluating questions for possible duplication? Is it sufficient to say \"Your answer can be found in this question over here, therefore your question is a duplicate?\" The new guidance is here: Among other things, it describes the new close banner: This question already has an answer here: Link to the Duplicate Question ... which seems to suggest that, if some other question in the system answers the OP's question, then the OP's question can be closed as a duplicate on that basis (even if the question itself is not necessarily duplicated). Example Here: Note the comments below the question, where I dispute the assertion made there that it is a duplicate question. The original question doesn't mention unit testing.", "Run command whenever someone joins a Minecraft server", "How were bullets able to dent Captain America's Shield? Just after Captain America's shield was introduced in Captain America: The First Avenger, Peggy Carter shot few bullets at it which created few minor distortions on it. From page of Marvel.Wikia, Proto-Adamantium This is the original Adamantium created by Dr. MacLain. Proto-Adamantium is the official name for the metal that makes up Captain America's Shield. It has never been recreated and is the absolute most invulnerable item in all of existence. From page of Marvel.Wikia: The true shield was once slightly dented by an enraged Odinforce empowered Thor, using Mjolnir, but he later reconciled and pounded out the small dent. How were few bullets able to dent Captain America's shield then?", "How do programmatically create fields for content types, and ADD them to the the content type form Say I have this field, \"map_description\". I know I would this function to define the field: $field = array( 'field_name' =&gt; 'map_description', 'cardinality' =&gt; 1, 'type' =&gt; 'text', ); field_create_field($field); And I have this code which I'm not sure what it does but I'm told that I'll need it: $instance = array( 'field_name' =&gt; 'map_description', 'label' =&gt; 'The map description.', 'bundle' =&gt; 'my_content_type', 'entity_type' =&gt; 'node', 'widget' =&gt; array( 'type' =&gt; 'text_textfield', ); field_create_instance($instance) Those two code bits are both in my install hook and run when I install the module. But while the fields are in fact created, I have to manually assign them to the content type via \"manage fields\", is there a way to have the fields automatically assigned to the content type?", "For every matrix $A\\in M_{2}( \\mathbb{C}) $ there's $X\\in M_{2}( \\mathbb{C})$ such that $X^2=A$?", "Financial proof to get a Schengen visa to France I am planning to apply for a Schengen visa to visit France. I have an attestation d'acceuil, but the visa requires I submit bank statement for the past 3 months. I can get this statement, but the problem is that my company has been paying my salary in cash for the past months, and I place the money into the account by myself. Can I submit the following? my accounting book (current account) letter from the bank stating that I have money in it payslips for the past 3 months Will that satisfy the financial requirements for the visa?", "How do I use extern to share variables between source files?", "Prove,by vector method,that the point of intersection of the diagonals of the trapezium lies on the line passing through the mid-points of the parallel sides. My Attempt: Let the trapezium be $OABC$ and that the O is a origin and the position vectors of $A,B,C$ be $\\vec{a},\\vec{b},\\vec{c}$.Then the equation of $OB$ diagonal is $\\vec{r}=\\vec{0}+\\lambda \\vec{b}................(1)$ And equation of $AC$ diagonal is $\\vec{r}=\\vec{a}+\\mu(\\vec{c}-\\vec{a}).......(2)$ And the equation of the line joining the mid points of $OA$ i.e.$\\frac{\\vec{a}}{2}$ and $BC$ i.e. $\\frac{\\vec{b}+\\vec{c}}{2}$ is $\\vec{r}=\\frac{\\vec{a}}{2}+t(\\frac{\\vec{b}+\\vec{c}}{2}-\\frac{\\vec{a}}{2}).........(3)$. Here $\\lambda,\\mu,t$ are scalars. I do not know how to solve $(1)$ and $(2)$ and put into $(3)$ to prove the desired result. Please help me.Thanks." ]

[ "How Do I get into the castle walls? I already have the pink and red leather gloves, the armor, the crown, and the monkey's staff (and they're all enchanted). Regardless of how many health potions I use, I always die. Help!", "How can I get the values of the parameters of a calling method? Question I'm writing some code that needs to be able to get the values of the parameters from the method that called into the class. I know how to get all the way to the ParameterInfo[] array, but I don't know how to then get the values. Is this even possible? If it is, I think it has something to do with using the MethodBody property from the MethodInfo object, which allows you to inspect the IL stream, including properties, but I don't know how to do it, and I haven't found applicable code on Google. Code // Finds calling method from class that called into this one public class SomeClass { public static void FindMethod() { for (int i = 1; i &lt; frameCount; i++) { var frame = new StackFrame(i); var methodInfo = frame.GetMethod(); if (methodInfo.DeclaringType != this.GetType()) { string methodName = frame.GetMethod().Name; var paramInfos = methodInfo.GetParameters(); // Now what?? How do I get the values from the paramInfos break; } else if (i == frameCount - 1) { throw new TransportException(\"Couldn't find method name\"); } } } }", "How do I hide Thunderbird from the launcher while running? I have a question for you all. It's possible to \"hide\" thunderbird from the unity application bar when thunderbird is running? For my is unhelpfull see thunderbird on the \"mail\" tray ( near shutdown button) and the unity \"running\" application. If i close thunder with the close button, it don't notify me new email.", "ESM is available for 12.04, which enables Advantage customers to keep receiving kernel updates and updates for many user space packages. In our case it's very important to know if we'll be able tot use Ubuntu 14.04 safely after April '19, because it is not possible to upgrade our application and migrate it to say, 16.04.", "Space between 2 paths in Illustrator", "I can print with printf as a hex or octal number. Is there a format tag to print as binary, or arbitrary base? I am running gcc. printf(&quot;%d %x %o\\n&quot;, 10, 10, 10); //prints &quot;10 A 12\\n&quot; print(&quot;%b\\n&quot;, 10); // prints &quot;%b\\n&quot;", "How do I fix my locale issue? I am getting this message every time I do something like starting or stopping a service. perl: warning: Setting locale failed. perl: warning: Please check that your locale settings: LANGUAGE = \"en_US:en\", LC_ALL = (unset), LC_MESSAGES = \"en_US.UTF-8\", LANG = \"en_US.UTF-8\" are supported and installed on your system. perl: warning: Falling back to the standard locale (\"C\"). locale: Cannot set LC_CTYPE to default locale: No such file or directory locale: Cannot set LC_MESSAGES to default locale: No such file or directory locale: Cannot set LC_ALL to default locale: No such file or directory (Reading database ... 21173 files and directories currently installed.) Removing bind9 ... * Stopping domain name service... bind9 [ OK ] Processing triggers for man-db ... locale: Cannot set LC_CTYPE to default locale: No such file or directory locale: Cannot set LC_MESSAGES to default locale: No such file or directory locale: Cannot set LC_ALL to default locale: No such file or directory How do I fix this error ?", "What are the differences in targets, and when should I switch to one? So I get the 4 options for target selection are: Attackers Badges Randoms K.O.s What I don't understand is the pros/cons for selecting each one, and what situations would make each one useful. Things like Badges and K.O. makes no sense to start off with because nobody starts off with badges, and nobody is going to start off near death unless they are purposely trying to lose (by hard dropping int he same position). I've tried the strategy then of just sticking with Attackers, but then I all of sudden get wave after wave of garbage late into the game. So it begs the question -- what are the differences in target choices, and how can I use that to my advantage to become a Tetris 99 champion?", "I'm trying to understand at a deeper level the ubiquity of log-likelihood (and perhaps more generally log-probability) in statistics and probability theory. Log-probabilities show up all over the place: we usually work with the log-likelihood for analysis (e.g. for maximization), the Fisher information is defined in terms of the second derivative of the log-likelihood, entropy is an expected log-probability, Kullback-Liebler divergence involves log-probabilities, the expected diviance is an expected log-likelihood, etc. Now I appreciate the many practical and convenient reasons. Many common and useful pdfs are from exponential families, which leads to elegantly simplified terms when log-transformed. Sums are easier to work with than products (esp for differentiating). Log-probs have a great floating point advantage over straight probs. Log-transforming a pdf often converts a non-concave function into a concave function. But what is the theoretical reason/justification/motivation for log-probs? As an example of my perplexity, consider the Fisher information (FI). The usual explanation for intuiting the FI is that the second derivative of the log-likelihood tells us how \"peaked\" the log-likehood is: a highly peaked log-likelihood means the MLE is well-specified and we are relatively sure of its value, while a nearly flat log-likehood (low curvature) means many different parameter values are nearly as good (in terms of the log-likelihood) as the MLE, so our MLE is more uncertain. This is all well-and-good, but isn't it more natural to just find the curvature of the likelihood function itself (NOT log-transformed)? At first glance the emphasis on the log-transform seems arbitrary and wrong. Surely we are more interested in the curvature of the actual likelihood function. What was Fisher's motivation for working with the score function and the Hessian of the log-likelihood instead? Is the answer simply that, in the end, we have nice results from the log-likelihood asymptotically? E.g., Cramer-Rao and normality of the MLE/posterior. Or is there a deeper reason?", "I a chat discussion it was suggested that \\hspace*{\\fill} (with a space before it to allow for a line break) was sufficient to always get the text following aligned to the right. And indeed, it is aligned to the right. However, in one case it is inserting an additional line break where one should not be required as illustrated by the last example here. I want the text bumped to the next line if and only if (iff ) there is no room: If I remove the space before the \\hspace*{\\fill}, there are cases (second and third) where a new line should have been inserted but is not: Related Question: I have tried the suggestions at the related question and: Martin Scharrer's suggestion of using \\hbox{}\\hfill results in the text being on the left for the last case. Herbert's \\When macro exhibits a similar problem for the last case. Thorsten Donig's \\signed macro does yield the correct number of lines, but portions of the file name for the middle two cases show up on the second line when they easily fit in the first line. Notes: I believe that this is unrelated to the problem, as I was able to reproduce the problem without it. But, am mentioning it here in case it causes an issue with the proposed solution. I am using \\texttt for the file name. This resulted in an additional complication which I initially thought was the cause of the problem. So, my actual use case is commented out below and it incorporates a solution from Code: \\documentclass{article} \\usepackage[paperwidth=7.0cm,showframe]{geometry} \\usepackage{xcolor} \\usepackage{xparse} \\newcommand*{\\FillLine}[2]{% \\noindent\\parbox{\\linewidth}{% \\raggedright File:~#2 % &lt;-- Need space here %Space before \\hspace* allows for a break before it \\hspace*{\\fill}\\texttt{\\small CONFIDENTIAL}% }% } %\\newcommand*{\\EnableHyphenationInTexttt}{\\hyphenchar\\font=45\\relax} % %\\newcommand*{\\FillLine}[2]{% % \\noindent\\parbox{\\linewidth}{% % \\raggedright % File:~\\texttt{\\EnableHyphenationInTexttt#2} % &lt;-- Need space here % %Space before \\hspace* allows for a break before it % \\hspace*{\\fill}\\texttt{\\small CONFIDENTIAL}% % }% %} \\begin{document} \\FillLine{Name}{Value} \\bigskip \\FillLine{Name}{A-Long-Value} \\bigskip \\FillLine{Name}{iiiiiii-iiiii-iiiiiii} \\bigskip \\FillLine{Name}{Some-Really-Really-Long-Value} \\end{document}", "How does Java's serialization work and when it should be used instead of some other persistence technique? I've been lately trying to learn more and generally test Java's serialization for both work and personal projects and I must say that the more I know about it, the less I like it. This may be caused by misinformation though so that's why I'm asking these two things from you all: 1: On byte level, how does serialization know how to match serialized values with some class? One of my problems right here is that I made a small test with ArrayList containing values \"one\", \"two\", \"three\". After serialization the byte array took 78 bytes which seems awfully lot for such low amount of information(19+3+3+4 bytes). Granted there's bound to be some overhead but this leads to my second question: 2: Can serialization be considered a good method for persisting objects at all? Now obviously if I'd use some homemade XML format the persistence data would be something like this &lt;object&gt; &lt;class=\"java.util.ArrayList\"&gt; &lt;!-- Object array inside Arraylist is called elementData --&gt; &lt;field name=\"elementData\"&gt; &lt;value&gt;One&lt;/value&gt; &lt;value&gt;Two&lt;/value&gt; &lt;value&gt;Three&lt;/value&gt; &lt;/field&gt; &lt;/object&gt; which, like XML in general, is a bit bloated and takes 138 bytes(without whitespaces, that is). The same in JSON could be { \"java.util.ArrayList\": { \"elementData\": [ \"one\", \"two\", \"three\" ] } } which is 75 bytes so already slightly smaller than Java's serialization. With these text-based formats it's of course obvious that there has to be a way to represent your basic data as text, numbers or any combination of both. So to recap, how does serialization work on byte/bit level, when it should be used and when it shouldn't be used and what are real benefits of serialization besides that it comes standard in Java?", "How do I calculate the resistor value for a simple LED circuit?", "Let $a,b$ be positive integers. When $$k = \\frac{a^2 + b^2}{ab+1}$$ is an integer, it is a square. Proof 1: (Ngô Bảo Châu): Rearrange to get $a^2-akb+b^2-k=0$, as a quadratic in $a$ this has two values: $a$ and $kb - a = (b^2-k)/a$. (The second root is determined in two different ways from the expansion $(x-r_1)(x-r_2) = x^2 - (r_1 + r_2)x + r_1 r_2$.) Now suppose we have $a,b$ such that $k$ is an integer but not a square, by the investigation about roots we have that the second root is a nonzero integer since $k,b,a$ are integers and $k \\not = b^2$, futhermore it is positive which is easily seen from its defining equation. WLOG assume $a \\ge b$ so that the second root is strictly smaller than $a$. This leads to a decent, replacing $a$ with the second root. Proof 2 (Don Zagier): Apply reduction theory (specifically, Sätze 1 and 2 of Section 13 of my book on quadratic fields) to the quadratic form $x^2 + kxy + y^2$, which is the unique reduced quadratic form in its equivalence class. Note that Proof 2 is pretty much the same as Proof 1 when written out in explicit detail, but I could not read Zagier's book because I cannot read German. I would like to know more approaches to this and other alternative proofs of this result if possible! Thanks in advance. I would also be interested in related problems (especially easier ones of a similar nature) and texts which cover the reduction theory in English.", "Why does exclamation mark within double quotes cause a Bash error? Please look at these commands: $ notify-send SYNC TIME! $ notify-send 'SYNC TIME!' $ notify-send \"SYNC TIME!\" bash: !\": event not found $ The first two commands produce a notification bubble as expected. The third gives the error shown. and $ echo SYNC TIME! SYNC TIME! $ echo 'SYNC TIME!' SYNC TIME! $ echo \"SYNC TIME!\" bash: !\": event not found $ Here as well, the echo works for first two commands but not in the third. More problems here (although I was not planning on using this): both notify-send \"SYNC!TIME\" and echo \"SYNC!TIME\" give bash: !TIME\": event not found. But both notify-send and echo work with \"SYNC! TIME\" Can someone please explain why the bash: !\": event not found error appears?", "I want to use Windows 7 or 8 but I don't know to install a software like VirtualBox which we have to do with the use of terminal. I don't want to use Windows as a main OS so I want to use it in VirtualBox. Can you tell me how to install downloaded files in Ubuntu. I once installed java runtime but don't know the meaning of the lines which I have written in terminal, I just did as the blog posted by a man says.", "Solve $\\lim_{x\\to 0} \\frac{\\sin x-x}{x^3}$", "Recent file in Macbook Air I am not a very techie girl. I used my brother's macbook air and saw some of his personal things which I should haven't. And I realised that he could see that in recents. How to delete them? After surfing a lot, I got to know about the recent files stored in plist in preferences, by the name com.apple.recentfiles.plist or LSSharedfiles.plist but I couldn't find a file/plist named above. Kindly help! As mentioned above it is macbook air and again I do not know much :(", "I tried out several image editors mentioned on but some of them (like and ) were very disappointing. These apps were too simple and low level. What do you suggest for a (preferably free) image editor on OS X? P.S: I was using on Linux and also know that it was released for OS X too, but I want to find new good applications.", "I have tried using glm::rotate and such. glm::translate works fine, but rotate doesn't work (if I rotate before/after a translation). Here is my current setup: glm::vec4 Off = glm::vec4(0, 0, 0, 1); glm::vec4 result = Util::createTransform(offset) * Off; for (int i = 0; i &lt; Tvertex.size(); i++) { Tvertex[i] += glm::vec3(result.x, result.y, result.z); Tcolors[i] = currentColor; } And here is my Util::createTransform: glm::mat4 Util::createTransform(glm::vec3 pos) { glm::mat4 trans = glm::mat4(1.0); trans = glm::translate(trans, pos); return trans; } glm::mat4 Util::createTransform(glm::vec3 pos, glm::vec3 rot) { glm::mat4 trans = glm::mat4(1.0); trans = glm::rotate(trans, glm::radians(rot.x), glm::vec3(1, 0, 0)); trans = glm::rotate(trans, glm::radians(rot.y), glm::vec3(0, 1, 0)); trans = glm::rotate(trans, glm::radians(rot.z), glm::vec3(0, 0, 1)); trans = glm::translate(trans, pos); return trans; }", "Change Proxy Settings In Ubuntu I want to use the Ubuntu Software Center to install software, but I cannot download them. How can I give my proxy settings in Ubuntu terminal (just like we use cmd in Windows to choose IE proxy settings)?" ]

[ "What's the easiest way to set up a LAMP stack? I set up a new VPS instance of Ubuntu and am wondering what the easiest way is to get up and running with a basic LAMP stack (i.e. which packages are required, which configuration options need to be tweaked, if any, etc.).", "Is there a built-in method to compare collections? I would like to compare the contents of a couple of collections in my Equals method. I have a Dictionary and an IList. Is there a built-in method to do this? Edited: I want to compare two Dictionaries and two ILists, so I think what equality means is clear - if the two dictionaries contain the same keys mapped to the same values, then they're equal.", "What are the differences between Factor Analysis and Principal Component Analysis?", "How to extract the last inserted row in SQL Server? When an insert statement is executed one or more rows is inserted into the table, is there any way to extract the last inserted row in SQL Server?", "Sending an HTTP request using QNetworkAccessManager", "What's the best way to return multiple values from a function? I have a function where I need to do something to a string. I need the function to return a boolean indicating whether or not the operation succeeded, and I also need to return the modified string. In C#, I would use an out parameter for the string, but there is no equivalent in Python. I'm still very new to Python and the only thing I can think of is to return a tuple with the boolean and modified string. Related question:", "If your application requires a database and it comes with built in data, what is the best way to ship that application? Should I: Precreate the SQLite database and include it in the .apk? Include the SQL commands with the application and have it create the database and insert the data on first use? The drawbacks I see are: Possible SQLite version mismatches might cause problems and I currently don't know where the database should go and how to access it. It may take a really long time to create and populate the database on the device. Any suggestions? Pointers to the documentation regarding any issues would be greatly appreciated.", "Is it possible to install MySQL 5.5 or 5.6 on Ubuntu 16.04? I recently upgraded to Ubuntu 16.04. Unfortunately I need to work MySQL 5.5 or 5.6. I tried many solutions to have MySQL 5.5 or 5.6 run on Ubuntu 16.04 like this . But none of them is working. Ubuntu detect the unmet dependencies but says \"but it is not going to be installed\" for 5.5 or says Package 'mysql-server-5.6' has no installation candidate... Is it not possible to force an earlier version of MySQL on Ubuntu? Why is that?", "I have a query going that gets data for an ID for the last 3 months. I need to tweak it so I get the highest value for each of the three months. I've tried a couple of things with the aggregate function MAX, but I'm not getting anywhere. I'm trying to get the max value for each of the past months .... Here's the data from the query, currently sorted by date (asc): ID Date Value 12410 01/03/2017 12:17 0.000178 12410 01/10/2017 11:36 0.000186 12410 01/17/2017 11:27 0.000189 12410 01/24/2017 13:09 0.000182 12410 01/31/2017 10:37 0.000169 12410 02/07/2017 11:03 0.000214 12410 02/14/2017 11:52 0.000176 12410 02/21/2017 10:51 0.000200 12410 02/28/2017 12:29 0.000194 12410 03/07/2017 08:39 0.000206 Here's the query: select AnalysisID as \"ID\" , AnalysisDateTime as \"Date\", AnalysisValue as \"Value\" from AnalysisValueTbl where AnalysisID = 12410 and DatePart(m, AnalysisDateTime) = DatePart(m, DateAdd(m, -3, getdate())) and DatePart(yyyy, AnalysisDateTime) = DatePart(yyyy, DateAdd(m,-3, getdate())) or AnalysisID = 12410 and DatePart(m, AnalysisDateTime) = DatePart(m, DateAdd(m, -2, getdate())) and DatePart(yyyy, AnalysisDateTime) = DatePart(yyyy, DateAdd(m,-2, getdate())) or AnalysisID = 12410 and DatePart(m, AnalysisDateTime) = DatePart(m, DateAdd(m, -1, getdate())) and DatePart(yyyy, AnalysisDateTime) = DatePart(yyyy, DateAdd(m,-1, getdate())) order by AnalysisValue desc", "\"is\" operator behaves unexpectedly with integers Why does the following behave unexpectedly in Python? &gt;&gt;&gt; a = 256 &gt;&gt;&gt; b = 256 &gt;&gt;&gt; a is b True # This is an expected result &gt;&gt;&gt; a = 257 &gt;&gt;&gt; b = 257 &gt;&gt;&gt; a is b False # What happened here? Why is this False? &gt;&gt;&gt; 257 is 257 True # Yet the literal numbers compare properly I am using Python 2.5.2. Trying some different versions of Python, it appears that Python 2.3.3 shows the above behaviour between 99 and 100. Based on the above, I can hypothesize that Python is internally implemented such that \"small\" integers are stored in a different way than larger integers and the is operator can tell the difference. Why the leaky abstraction? What is a better way of comparing two arbitrary objects to see whether they are the same when I don't know in advance whether they are numbers or not?", "What is the proper usage of \"not only... but also\"? I'm trying to figure out how to use \"not only... but also\" properly. Basically, my goal is to combine two clauses by using \"not only\". For negations, I've figured out two styles that both sound correct: He knew that if he fractures his finger, not only would he not be able to compete in the water polo tournament, he would not be able to take the SAT on Monday, either. He knew that if he fractures his finger, neither would he be able to compete in the water polo tournament, nor would he be able to take the SAT on Monday. However, I don't know how to form a sentence that does not include a negation while using \"not only\". Here are a few possibilities that I've considered: Thanks to his remarkable performance on the SAT, not only was he accepted into Harvard, but he was also given a full scholarship. Thanks to his remarkable performance on the SAT, not only was he accepted into Harvard, but he was given a full scholarship. Thanks to his remarkable performance on the SAT, not only was he accepted into Harvard, he was given a full scholarship. Thanks to his remarkable performance on the SAT, not only was he accepted into Harvard, he was also given a full scholarship. In those four possibilities, I'm varying the usage of \"but\" and \"also\" in the last clause. What is the proper usage of \"not only\"?", "How to correctly assess the correlation between ordinal and a continuous variable? I'd like to estimate the correlation between: An ordinal variable: subjects are asked to rate their preference for 6 types of fruit on a 1-5 scale (ranging from very disgusting to very tasty) On average subjects use only 3 points of the scale. A continuous variable: the same subjects are asked to quickly identify these fruits, which results in an mean accuracy for the 6 fruits. Is Spearman rho the best method to analyze these data and/or are there other good methods I could consider?", "Can I visit the UK as a tourist before my Student Visa starts?", "Generics and inheritance: need a complex Map instance", "Difference between \"I'm home\" vs \"I'm at home\"", "What is the difference between \"retired out\" and \"retired not out\" in cricket?", "Could someone please provide an explanation for the origin of ? (Ideally someone who I have been speaking with on the h-bar) Any advanced maths beyond basic calculus will most probably leave me at a loss, though I do not mind a challenge! Please assume little prior knowledge, as over the past few days I have discovered that much of my understanding surrounding the process as virtual particle pairs is completely wrong.", "How long can I store a food in the pantry, refrigerator, or freezer? How do I know if a given food or ingredient I have is still good, or if I should discard it? How can I best preserve a food or ingredient? This broad question is intended as a \"general reference\" question to quickly answer many how long will food keep for? questions. Please feel free to edit this question to expand and clarify as needed.", "Creating a .desktop file for a new application", "How to set the command prompt's color in Bash?" ]

[ "I have a question about using the phrase \"some kind of _\". Is it incorrect to say \"some kind of + plural noun\"? For example, is it wrong to say \"are these rock-like things some kind of chocolates?\" I didn't use \"kinds\" and that kind of adds to my question. Is \"kind\" always plural, like \"some kinds of chocolates\"? Because although I'm using \"some\", it feels like \"kind\" shouldn't be a countable noun. Anyway, I don't think I've heard of \"some kind of + plural\", but I think it makes more sense then using singular, since I think chocolates are countable. Please help!", "How do I arrange selected vertices into a circular formation quickly? The other answers does not have the same title as my question. My question is direct and simple for younger beginner to search for results.", "Why do different humans look different? Although farmers appear to be able to tell their cows apart, cows look very much alike to me. And this similarity in appearance seems to be a general trait across the animal kingdom: one individual of one animal species looks much like another. Why do human facial and body shapes vary so much? I understand that human beings live in many different environments (e.g. hot and cold) and have adapted to these (e.g. through lighter or darker skin color), but there seems to be much variation that has no apparent evolutionary purpose. So does the difference have a purpose in itself? That is, did we evlove to vary in appearance, and what is the purpose of this variation?", "In a preadditive category, products are coproducts $\\renewcommand{\\phi}{\\varphi}$ $\\require{AMScd}$ My question is different from . I want to see how in a preadditive category $\\mathcal{C}$ a product is a coproduct, following . I'll write the proof up to the point where I get stuck. Let $A=A_1,B=A_2$ be objects and suppose their product $P$ does exist, with projections $\\pi_i:P\\rightarrow A_i$. By considering a wedge $$\\begin{CD}A @&lt;{id_A}&lt;&lt; A @&gt;{0_{AB}}&gt;&gt; B\\end{CD}$$ and the obvious analogous one with $A$ and $B$ exchanged, where $0_{A,B}$ is the zero morphism, we see that the product property implies the existence of two unique morphisms $k_i\\in\\mathcal{C}[A_i,P]$ s.t. \\begin{align*} \\pi_j\\circ k_i=\\begin{cases} \\mathrm{id}_i &amp;\\text{if }i=j\\\\ 0_{A_i, A_j} &amp;\\text{if }i\\neq j \\end{cases}. \\end{align*} Using these equations and the definition of zero morphism, it's easy to see that the morphism $m\\equiv k_1\\circ \\pi_1+ k_2\\circ \\pi_2$ satisfies $\\pi_i\\circ m=\\pi_i$. This is where I get stuck: In the linked proof, they now state that this implies $m=\\mathrm{id}_P.$ But I don't see why this should be true. Specifically, if $\\phi\\in\\mathcal{C}[S,P]$ for some arbitrary object $S$, it is not apparent why $m\\circ\\phi=\\phi$. All that we know is that there are some morphisms $x_i\\in\\mathcal{C}[S,A_i]$ that factor through $P$ via the universal property, but these are not necessarily unique. And we learn even less about $m$ by looking at morphisms in $\\mathcal{C}[P,S]$. What am I missing here?", "JavaScript object: access variable property by name as string", "@online bibliography biblatex", "I'm not sure how to go about this. Does it involve using MVT? I got as far as saying $e = \\frac{e^x - e^y}{x-y}$.", "Why is the Yang–Mills existence and mass gap problem so fundamental? Ref: Can anyone please explain why the Yang–Mills Existence and Mass Gap problem is so important / fundamental to contemporary mathematics (and, presumably, theoretical / mathematical physics)? If possible, please include the following in your answer / response: (1) Why the problem is so fundamental / important - for both mathematics and theoretical / mathematical physics; (2) How the solution to the problem would impact research in the above two fields; (3) (If applicable) What progress has been made so far in resolving it; (references to papers, books, other resources would be helpful). I'm an upper-level undergraduate in theoretical physics, and so am seeking an answer / response at such level.", "Prevent Windows 10 from installing/updating a specific driver? It seems that the recent Synaptics driver update for Synaptics SMBus TouchPad on Windows 10 (build 100049) somehow doesn't see my middle-button. Uninstalling, and installing an older driver for Windows 8.1 from the HP site (my machine is HP EliteBook 8570w) restores the middle button functionality. Few days later, the driver updates itself again, and I lose the middle-button. I realize I'm running unsupported software, but is it possible to prevent updating this particular driver, without either disabling updates altogether or preventing other drivers from updating?", "How do you prove the second law of thermodynamics from statistical mechanics?", "Traffic (views, visits) is not correctly registered on Site Analytics or Area 51 In the , can monitor some things like the total traffic on the site. However, it seems to be broken at the moment, all figures are almost zero. This is how it looks for Meta Stack Exchange (other sites show similar pictures):", "Why doesn't Steam start? When I try to start Steam nothing happens. Reinstall doesn't help. $ steam Running Steam on ubuntu 13.04 64-bit STEAM_RUNTIME is enabled automatically Installing breakpad exception handler for appid(steam)/version(1378500910_client) Installing breakpad exception handler for appid(steam)/version(1378500910_client) Installing breakpad exception handler for appid(steam)/version(1378500910_client) unlinked 0 orphaned pipes removing stale semaphore last operated on by process 7278 with name 0eBlobRegistryMutex_DC7EBB4AEA41D3C6C74E5EFFD6757CEC removing stale semaphore last operated on by process 7278 with name 0eBlobRegistrySignal_DC7EBB4AEA41D3C6C74E5EFFD6757CEC removing stale semaphore last operated on by process 7278 with name 0emSteamEngineInstance removing stale semaphore last operated on by process 7278 with name 0eSteamEngineLock Gtk-Message: Failed to load module \"overlay-scrollbar\" Installing breakpad exception handler for appid(steam)/version(1378500910_client) [0913/182910:WARNING:proxy_service.cc(958)] PAC support disabled because there is no system implementation How to fix it?", "Does personified Death really exist in Harry Potter? I went through the last book, Harry Potter and the Deathly Hallows, yesterday and a question popped in my mind: Does Death, the supposed creator of the Deathly Hallows, really exist in the Harry Potter universe? Dumbledore thought otherwise and I am with the same school of thought. By the way who created the deathly Hallows actually? Update: 1) Why were the brothers so sure that the hooded figure was death(couldn't it be a more powerful wizard playing with them) 2) Couldn't, Beedle and the brothers create this story?", "Creating controls within a Loop I have have some code which adds new cells to a table and fills them with text boxes. The way I've coded it so far works fine: TableCell tCell1 = new TableCell(); TableCell tCell2 = new TableCell(); TableCell tCell3 = new TableCell(); TableCell tCell4 = new TableCell(); TableCell tCell5 = new TableCell(); TableCell tCell6 = new TableCell(); TableCell tCell7 = new TableCell(); TextBox txt1 = new TextBox(); TextBox txt2 = new TextBox(); TextBox txt3 = new TextBox(); TextBox txt4 = new TextBox(); TextBox txt5 = new TextBox(); TextBox txt6 = new TextBox(); TextBox txt7 = new TextBox(); tCell1.Controls.Add(txt1); tCell2.Controls.Add(txt2); tCell3.Controls.Add(txt3); tCell4.Controls.Add(txt4); tCell5.Controls.Add(txt5); tCell6.Controls.Add(txt6); tCell7.Controls.Add(txt7); tRow.Cells.Add(tCell1); tRow.Cells.Add(tCell2); tRow.Cells.Add(tCell3); tRow.Cells.Add(tCell4); tRow.Cells.Add(tCell5); tRow.Cells.Add(tCell6); tRow.Cells.Add(tCell7); As you can see there's basically 4 instructions getting repeated 7 times. I'm sure there has to be a way to accomplish this with just 4 lines of code within a FOR loop and having all the names dynamically assigned but I just can't seem to find anything that would point me in the direction of how to do it. Something like the following is what I'm after: for (int i = 0; i &lt; 6; i++) { TableCell tCell[i] = new TableCell(); TextBox txt[i] = new TextBox(); tCell[i].Controls.Add(txt[i]); tRow.Cells.Add(tCell[i]); } Any help would be much appreciated.", "Why can't I say “She died from drinking 18 cans of Coca-Cola”? Instead, the correct sentence would be “She died of drinking 18 cans of Coca-Cola”. Why does that happen?", "How do you kill the devil?", "Scoring when two triple word squares are covered in one play The word QUAGMIRE is on the board vertically, with the Q on the top row, second column. The next player creates SQUEEZED horizontally, landing the S on the triple word square in the top row, first column, and remaining UEEZED landing to the right of the existing Q, ending with the D on the triple word square in the eighth column. Since two triple word squares are covered in this one placement, how would it be scored? Letters: S: 1 Q: 10 U: 1 E: 1 x 2 (double letter) E: 1 Z: 10 E: 1 D: 1 27 Total for letters. Do you then multiply by 3 for the first triple word square, and then multiply that result by 3? 27 X 3 = 81, 81 X 3 = 243 Bonus for all 7 tiles placed: 243 + 50 = 293", "Does anyone know of any good tools (I'm looking for IDEs) to write assembly on the Mac. Xcode is a little cumbersome to me. Also, on the Intel Macs, can I use generic x86 asm? Or is there a modified instruction set? Any information about post Intel. Also: I know that on windows, asm can run in an emulated environment created by the OS to let the code think it's running on its own dedicated machine. Does OS X provide the same thing?", "Is there a term for words that when reversed, form other words? I'm aware of what a palindrome is. What do you call words that, when reversed, form other words, such as ton (not) and part (trap)?", "Parse JSON with R" ]

[ "The system of equations Let $a,b,c\\in \\mathbb{R}$ that $a^{2}+b^{2}+c^{2}=1$. We want to find $x,y,z,w$ in the following equations: $$\\begin{align} x^{2}+y^{2}+z^{2}+w^{2}&amp;=1 \\tag{1}\\\\ x^{2}+y^{2}-z^{2}-w^{2}&amp;=a \\tag{2}\\\\ xw+yz&amp;=2b \\tag{3}\\\\ yw-xz&amp;=2c.\\tag{4} \\end{align}$$", "LIGO has announced the detection of gravitational waves on 11 Feb, 2016. I was wondering why the detection of gravitational waves was so significant? I know it is another confirmation of general relativity (GR), but I thought we had already confirmed GR beyond much doubt. What extra stuff would finding gravitational waves teach us? Is the detection of gravitational waves significant in and of itself, or is there data which can be extracted from the waves which will be more useful?", "How to add desktop shortcut for URL, ignoring web app manifest? Goal: Have a desktop shortcut that opens , ignoring the contained web app manifest that otherwise \"overrides\" the saved shortcut to and with \"display\": \"standalone\". I had this working previously on an older Android phone before a replacement / upgrade. Prior to the upgrade, I was able to long-press and open individual articles in new tabs - as well as copy link shortcuts to specific articles, as well as all of the other features and functionality that Chrome has to offer. Here is just a partial selection of references of other users complaining about the same: Using provides a temporary successful work-around. However, I can't find a successful way to add a link for this to my home screen. The \"Add to Home screen\" option within Chrome instead saves a link to - and in such a way that it opens as a web application instead of a web page within Chrome: On a desktop operating system, this would be a non-issue. (Create shortcut, enter desired URL, done.) Attempt 1: Provide my own Manifest So I created my own manifest - editing to change the start_url attribute to https://news.google.com/news/i#0, and the display attribute from standalone to browser. I then created my own HTML page that simply contained the below - then self-hosted both on a local web server: &lt;html&gt; &lt;head&gt; &lt;Title&gt;Google News&lt;/Title&gt; &lt;link rel=\"manifest\" href=\"/news/manifest.json\"/&gt; &lt;/head&gt; &lt;body&gt; Test &lt;/body&gt; &lt;/html&gt; However, this doesn't work: Despite the shortcut being saved with the desired name and icon, it links back to my self-hosted HTML page, and not the indicated start_url. Unfortunately, it appears that cross-domain URLs are not allowed per the manifest intent - as per and . Attempt 1b: MITM website Within the confines of my own local network, I figured I could try to (MITM) the website to temporarily provide a desired manfiest to use for addition to the home screen. Unfortunately, the website uses here, which appropriately blocks the attempt. Regardless - this is way too much work for what should be a simple effort. Attempt 2: Widget Bookmark Unfortunately, it looks like the 1x1 bookmark widget was removed in Chrome 48, as per . The suggested work-around is to use the \"Add to Home screen\" feature within Chrome. Goto 10 / see beginning. Attempt 3: Use the default-provided \"Internet\" browser Unfortunately, using \"Add shortcut on Home screen\" in the default-provided \"Internet\" browser produces the same result as Chrome. Consideration 4: Use a custom app / widget Could probably write and install a custom application or widget that could be added to the home screen to meet the goal. Or don't re-invent the wheel, and use an existing one. Some possibilities: \"More Shortcuts\": \"Shortcut Customizer\": Conclusion How can someone create a desktop shortcut to an arbitrary URL, ignoring a provided web app manifest?", "Is it \"I\" or \"me\" in \"Keep Tom and I/me updated\"? In this case what is correct? Keep Tom and I updated. or Keep Tom and me updated. I understand that me is an object pronoun. And therefore I feel the second option is correct. Especially, because I would say \"Keep him updated\" and also \"Keep me updated\". Instead of \"Keep he updated\" or \"Keep I updated\". But something about saying \"Keep him and me updated\" feels wrong. However I am not sure, because several people have told me that in this case I is the correct option because it is being used in conjunction with a name (Tom) and not a pronoun. Is that correct?", "What do you call the feeling you get when you're satisfied to the point of nausea? So you're craving something, say a particular chocolate or sex with one very attractive person that you desire. Take the sexual encounter one for example. You sleep with the person so many times until you are fulfilled. But it gets somewhat \"nauseating\" to enjoy that thing again (the sex or the chocolate) because you've overindulged earlier. Now what is that feeling called, the feeling of being overly \"satisfied\" or \"quenched\" to the point of nausea? I wouldn't say what I'm looking for is satisfaction or quench. Is there a more specific term? Example sentence: \"I've been eating T-bone steak all day yesterday. I had leftovers today, but I couldn't eat them - I'm just so ____ towards (or from) steak right now.\"", "Is Tactical Down-Voting ever valid? Has anyone noticed any tactical downvoting of their, or other people, answers? For example, in a recent answer to a question, my answer described a possible solution. Shortly afterwards, another answer appeared following the solution I had mentioned. I know that this is completely in the spirit of the site, however my answer had been down voted even though it was still as valid as it ever was. Another poster also had his equally valid solution down voted. There is no way of knowing the reason behind the down voting, as no comments were left, but I am suspicious as to the ethics behind down voting someone else's valid answer in the hope of making their own answer more prominent. Are people really that desperate to gain reputation? I have seen comments in other posts that suggest that tactical downvoting has occurred. So, does anyone think that it is acceptable to downvote another post, even though it is still correct but may not provide a complete answer, to make their own appear more favourably?", "Measuring the distance between lines and points in QGIS Using QGIS - I have a vector of fault lines. I have point data in the form of a csv which I have also loaded into QGIS. I need to know how far each point is from the nearest fault line then enter this distance in a new column in the csv file. Any ideas?", "Using \\@-ified punctuation while using \\frenchspacing After reading about spacing and punctuation, I was left wondering about an issue that didn't seem to be addressed: using \\frenchspacing together with the modified punctuation \\@., \\@?, etc. As far as I can tell visually, using \\frenchspacing together with these commands works correctly (i.e., it seems like nothing breaks, and the extra space is suppressed as normal), but are there problems that can arise from doing so? Moreover, when using \\frenchspacing, \"should\" I still use \\@. and its friends where it would ordinarily be necessary, in case someone wants to remove \\frenchspacing later? Would accommodating (hypothetical) future editors in this way be \"standard\", \"above and beyond the call of duty\", or \"crazy\"?", "I've been asked to show that: $n(n+1)(2n+1) \\equiv 0 \\pmod 6$ I found in a previous question that: $n(n+1)$ was divisible by $2$ and resulted in an even number e.g $n(n+1) \\equiv 0 \\pmod 2$ so I figured I needed to find: $(2n+1) \\equiv 0 \\pmod 3$ in order to complete $n(n+1)(2n+1) \\equiv 0 \\pmod 6$ but I am unsure on how to find $(2n+1) \\equiv 0 \\pmod 3$ Is this the right way to find the mod 6 and if so could you tell me how I could find $(2n+1) \\equiv 0 \\pmod 3?$", "I've deleted a system file from my Mac and need to get it back. System files can include: hidden files in the root of / - especially unix files in /private /System files /Library files /Applications files that ship with the core OS System files are not any app, user files or files that can be regenerated by a known sequence such as cache files, Spotlight index files, etc… Canonical question and answer for .", "Cyclic vector implies commuting linear operator is a polynomial Let $T$ be a linear operator on the finite dimensional vector space $V$. Suppose $T$ has a cyclic vector. Prove that if $U$ is any linear operator which commutes with $T$, then $U$ is a polynomial in $T$.", "Changing projection of shapefile in QGIS", "Android app - can I see interesting questions? On the website the default list of questions displays interesting tab (which I believe has questions based on my highest scoring tabs). That's very convenient and allows me to check new questions that are relevant for me easily. Can the same view be added to the mobile app?", "Why does this PNG image on twitter look different when clicked? This morning on twitter there was a tweet with the text \"click on this picture\". When picture is clicked, it's opened in wider viewer, but looks completely different. I tried to analyze this picture in ACDSee, and I also tried uploading on Facebook, but it's happening only when embedded on twitter. I don't have much knowledge about graphics so please explain this to me. Why does this PNG image change only when clicked on Twitter? Screenshots (left = before clicking; right = after clicking): Here's the original .", "$ is not a function in drupal 7 theme", "A 'for' loop to iterate over an enum in Java", "Prevent Mac Terminal from reverting to default theme I can't find any way to change the Terminal theme and have that theme applied permanently. I want to change to another darker theme other than the default 'basic' theme, and (most importantly) have it remain as the theme every time I open Terminal.", "What is wrong with the De Broglie–Bohm theory a.k.a \"Causal Interpretation\" of quantum theory? Possible Duplicate: I've heard of De Broglie–Bohm theory a.k.a causal interpretation of quantum theory. The predictions match accurately with with the nondeterministic quantum theory. As a philosophy buff this one seems just like the classical universe. No funny new-age religion style gimmicks. So why don't people use this interpretation instead of the Copenhagen \"magic\" interpretation? P.S. I'm not an expert. I possess only superficial knowledge of quantum physics.", "Why is time special? In Special Relativity, the spacetime interval between two events is $s^2 = -(c{\\Delta}t)^2+({\\Delta}x)^2+({\\Delta}y)^2+({\\Delta}z)^2$ giving the Minkowski metric $\\eta_{\\mu\\nu}=\\text{diag}(-1, 1, 1, 1)$. What is the justification for making time have a negative coefficient, and how closely is that related to the 2nd law of thermodynamics? Sure, by letting $\\eta = \\text{diag}(1, 1, 1, 1)$, we get a pretty boring spacetime, and the boosts in the Poincaré group become trig instead of hyperbolic functions, but what's the physical reasoning behind this?", "Subscribing to questions and comments that don't belong to you There has been some discussion about getting notified on comments to questions or answers that don't belong to you, and the long-standing wish to be able to keep track of new answers or developments in questions asked by other people. Previous discussion in regards to subscribing to questions: (very similar to this one) In regards to subscribing to comments: The general feeling - at least here on meta - seems to be against broadening the notification rules, out of fears of useless notifications to flood users' inboxes, turning SO into more of a discussion forum than it should be, etc. Here's a suggestion that would keep the user 100% in control what they get notified about, not generate any notifications by default, and require only minimal modifications to the User Interface. Each question and each comment area would get an envelope symbol. it is inactive (=white) by default. When those envelopes are hovered over, the tooltip says click to subscribe or something. When clicked on, the envelope lights up in green or some other colour (but different from the actual notification envelope's orange to avoid confusion.) You are then subscribed to any updates to that question or comment thread. For each subscription, you receive notifications in the \"responses\" tab, as if you were the owner of the comment or question. To unsubscribe from a question or comment thread, you open the page, and click the green envelope. It turns back white, and the notifications disappear from your responses tab (if technically possible - otherwise, there just won't be any new ones added.) No further functionality, like managing subscriptions or anything, is necessary IMO. If the flood of notifications from a subscribed question starts to annoy you, you just open it and unclick the envelope. Done. It would make it possible to leave a comment to a newbie's question and make sure their answer reaches you even if they don't know they need to address you using @username You could subscribe to those \"oh, I'd like to know the answer to that\" questions and receive active notification, instead of them getting forgotten in your favourites list You could subscribe to discussions you are interested in the outcome of, but don't want to participate in. It would (in my opinion) sort out a number of woes aired by many users in a good way, without adding annoyances to those who like the system just fine the way it is. It would not require a change in the visible layout. As far as I can see, the space the envelope would need to be is empty everywhere. I don't know SO under the hood of course, but technically, the system would be doing what it's doing already, notify question owners of updates - just that the circle of internal \"owners\" would grow." ]

[ "How to install (old) packages for Ubuntu 9.04? Based on some excellent feedback by Mark here (), today I was able to use the vmware converter to clone my production server for a staging server. However the nic won't come up no matter what I do. I attempted to inistall vmware tools, as I suspect that the fact that it is not installed might prevent the nic from working. (I have the nic set as a vmxnet3 card in the vm settings). The install failed because there were several dependencies missing as well as the Linux headers. Given that Ubuntu 9.04 has been EOL'd, the packages I need to install to get the vmware tools to install are no longer available. I doubt the ubuntu 9.04 install CD has the packages on it. What are my options? I'd rather not upgrade the version of Ubuntu yet, as the point of the vm right now is to maintain parity with the production server. Might I have better luck resetting the driver to use vmxnet2 instead of the vmxnet3? Thanks in advance! Chris", "Proving the identity $\\sum_{k=1}^n {k^3} = \\big(\\sum_{k=1}^n k\\big)^2$ without induction I recently proved that $$\\sum_{k=1}^n k^3 = \\left(\\sum_{k=1}^n k \\right)^2$$ using mathematical induction. I'm interested if there's an intuitive explanation, or even a combinatorial interpretation of this property. I would also like to see any other proofs.", "Merge two unadjacent partitions I have three partitions on my drive, arranged something like the following: ___________ | 1 | 2 | 3| ------------- I wish to merge partitions 1 and 3. Is there a way to do this, or do I have to manually \"slide\" partition 2 over to partition 3, and then merge the newly open space where partition 2 used to be? Note: I do not have the space to copy partition 2 to partition 3 (2 is 200GB and 3 is 65GB).", "I gave a quick answer to part of which had not been covered by previous answers, trying to clarify the reason you would say time of decoding but not decoding’s time. I said it was ’s usually indicates possession, but of course there were several counterexamples that would have occurred to me after a moment’s consideration, and these where helpfully supplied: Britain’s climate two days’ time a day’s work the sun’s rays I am still of a mind to say that possession of some sort is what allows the ’s. Even though the sun does not have title to its rays, they do belong to the sun. Now, at the risk of duplicating the original question and/or being pigheaded, I am curious as to why time of decoding but not decoding’s time is correct, if not for the reason I gave.", "If $f$ is entire and $|f|\\geq 1$, then show $f$ is constant. I know I'm going to use Liouville's Theorem, but my main question is why is $1/|f(z)|$ entire as well if $f$ is entire? Is this just a basic property: if $f$ is entire, then $1/f$ is entire? Thanks for the help.", "Is there an exception to the prohibition against ending a sentence with “ ’s ” at work here? The ’s can be used as a contraction representing a weak, unstressed word that is not pronounced. It allegedly cannot occur in sentence final position. She is not ready, but he is. She’s not ready, but he is. She’s not ready, but *he’s. The last one is not grammatical there. Similarly, here the last one is not grammatical: He has not started yet, but she has. He’s not started yet, but she has. He’s not started yet, but *she’s. claims this is because you cannot end a sentence with a weak form. It backs up its point with reasonably scholarly documentation. However, this does not seem to be invariably true. Shall we go to the movies? Yes, let us go. Shall we go to the movies? Yes, let’s go. Shall we go to the movies? Yes, let’s. Unlike the third example in the first two sets, here in this case the third example is indeed grammatical, despite ending with a weak form. Is this an exception to the rule, or is there another rule at work here?", "Moderncv adding date of birth to personal information I'm doing my cv with the moderncv package and I'm using the classic style. I would like to add a date of birth line directly above the adress. Does anyone know how to do this? I've tried various solutions but they all seem to be broken.", "Why Did Anakin Skywalker Believe that Turning to the Dark Side of the Force Would Save Padmé? Just as the question asks: Why did Anakin come to believe that Padmé could be saved if he embraced the Dark side of the Force? Padmé clearly didn't believe it. Why was Anakin so driven to save Padmé through the dark side?", "Intuition on the Kullback–Leibler (KL) Divergence", "How to prove the Fibonacci sum $\\sum \\limits_{n=0}^{\\infty}\\frac{F_n}{p^n} = \\frac{p}{p^2-p-1}$", "Ubuntu 18.04 No WiFi adapter found [Dell Inspiron 3542.]", "Evaluating the product $\\prod\\limits_{k=1}^{n}\\cos\\left(\\frac{k\\pi}{n}\\right)$ Recently, I ran across a product that seems interesting. Does anyone know how to get to the closed form: $$\\prod_{k=1}^{n}\\cos\\left(\\frac{k\\pi}{n}\\right)=-\\frac{\\sin(\\frac{n\\pi}{2})}{2^{n-1}}$$ I tried using the identity $\\cos(x)=\\frac{\\sin(2x)}{2\\sin(x)}$ in order to make it \"telescope\" in some fashion, but to no avail. But, then again, I may very well have overlooked something. This gives the correct solution if $n$ is odd, but of course evaluates to $0$ if $n$ is even. So, I tried taking that into account, but must have approached it wrong. How can this be shown? Thanks everyone.", "What method in the String class returns only the first N characters?", "Prove $\\mathbb{P}(\\sup_{t \\geq 0} M_t > x \\mid \\mathcal{F}_0)= 1 \\wedge \\frac{M_0}{x}$ for a martingale $(M_t)_{t \\geq 0}$ Let $M$ be a positive, continuous martingale that converges a.s. to zero as $t$ tends to infinity. I now want to prove that for every $x&gt;0$ $$ P\\left( \\sup_{t \\geq 0 } M_t &gt; x \\mid \\mathcal{F}_0 \\right) = 1 \\wedge \\frac{M_0}{x}. $$ My approach: I thought that rewriting the conditional probability to an expectation would help so we obtain that we must prove: $$ \\mathbb{E} \\left[ 1_{\\sup_{t \\geq 0 } M_t &gt; x} \\mid \\mathcal{F}_0 \\right] = 1 \\wedge \\frac{M_0}{x}.$$ A hint to me was given that I should consider stopping the process when it gets above $x$. Thus a stopping time that would do this is $\\tau = \\inf\\{t\\geq 0 : M_t&gt;x\\}$. But now I'm stuck as I want to apply optional sampling results but we have an indicator which complicates things. How could I proceed from this? Any help is appreciated!", "Assign VNC password using script I am using a script to automatically set up a computer. I need to assign a password to the vnc server for the user, which is normally done using the vncserver command. However, it prompts for the user to enter and re-enter their password, neither of which the script is capable of doing. So, how can I set up the VNC password without an interactive prompt? Thanks.", "What are the options for traveling to the airports in Paris? Paris has 3 airports (Orly, Roissy, Beauvais), what are the options to go to or to come from there? (There is also Vatry (XCR) but there is very few flights and i see the shuttle system is currently off.)", "Pressure variation in a sound wave", "Single word to denote date and time I want one word that means Date and Time. For example in \"the date and time of the event will be announced later\" I want to use single word instead of \"date and time\"", "Why is this sentence wrong? \"He went to home.\"", "I have a requirement where a future method need to be called from batch apex ,I came across various articles stating that a future method could not be called from the batch. Is there any alternate solutions for that?" ]

[ "How to show path-connectedness of $GL(n,\\mathbb{C})$ Well, I am not getting any hint how to show $GL_n(\\mathbb{C})$ is path connected. So far I have thought that let $A$ be any invertible complex matrix and $I$ be the idenity matrix, I was trying to show a path from $A$ to $I$ then define $f(t)=At+(1-t)I$ for $t\\in[0,1]$ which is possible continous except where the $\\operatorname{det}{f(t)}=0$ i.e. which has $n$ roots and I can choose a path in $\\mathbb{C}\\setminus\\{t_1,\\dots,t_n\\}$ where $t_1,\\dots,t_n$ are roots of $\\operatorname{det}{f(t)}=0$, is my thinking was correct? Could anyone tell me the solution?", "Find all solutions to $x^9 \\equiv 25 \\pmod {29}$", "How to prevent Windows from entering idle state?", "Question about Coulomb's law I am just very confsed about how to do these sort of questions where they give you a point in the middle of two charges. The farthest I've gotten in questions relating to coulomb's law, is using the formula \\$F = {kq_1q_2 \\over d^2}\\$ to work out one of the unknowns when given two variables. Can someone please explain how you would do a question like this: Two point charges of charge -2 µC and -3 µC respectively are separated by a distance of 15 cm. Point X is positioned at an equal distance away from each of the charges. a. Determine the net electric field at X. b. Find the point of equilibrium between the charges.", "We moved to a new place where the dryer connection is 3-prong instead of 4-prong. The dryer was originally 4-prong, so we bought a 3-prong cord and installed it. It works fine, except I am not entirely sure if I installed the ground wire correctly. Originally, there was a green wire on the cord itself, and that was connected to the screw on the top of the first picture. This is, I assume, used to ground the case and prevent shocks when touching the exterior of the dryer. Now with the 3-pronged plug, there is no ground wire on the cord. So where does the existing green wire in the case go? Do I leave it where it originally was like in the first picture or do I connect it to the central terminal like in the second picture? There's no bonding strap running from the case to any terminal. I can't tell where the green wire is connected to.", "CSS bug with printing site pages (now with 100% more suggested fix included!)", "Need help to understand Maximum Likelihood Estimation for multivariate normal distribution? In maximum likelihood estimation for the parameter, mean $\\mu$ of multivariate normal distribution, I end up with the following result: $\\mu_{MLE} = \\dfrac{1}{n}\\sum_{i=1}^n x_i$ The way I understand the above equation is the following way below, but I am wondering if the above equation means the following equation: $\\mu_{MLE} = \\begin{bmatrix}\\mu_1\\\\\\mu_2\\\\\\vdots\\\\\\mu_n\\end{bmatrix} = \\begin{bmatrix}\\dfrac{1}{n}\\sum_{i=1}^n x_1\\\\\\dfrac{1}{n}\\sum_{i=1}^n x_2\\\\\\vdots\\\\\\dfrac{1}{n}\\sum_{i=1}^n x_i\\end{bmatrix} = \\begin{bmatrix}E(X_1)\\\\E(X_2)\\\\\\vdots\\\\E(X_n)\\end{bmatrix} = \\begin{bmatrix}\\bar{X_1} \\\\ \\bar{X_2} \\\\ \\vdots \\\\ \\bar{X_n}\\end{bmatrix}$ And also Maximum Likelhood Estimation for $\\Sigma$, I have ended up with the following equation: $\\Sigma_{MLE} = \\dfrac{1}{n}\\sum_{i=1}^n(x_i-\\mu)(x_i-\\mu)^T = \\begin{bmatrix}Var(\\sigma_{11}) &amp; Cov(\\sigma_{12}) &amp; \\dots &amp; Cov(\\sigma_{1n}) \\\\ Cov(\\sigma_{21}) &amp; Var(\\sigma_{22}) &amp; \\dots &amp; Cov(\\sigma_{2n}) \\\\ {}&amp; \\vdots&amp; \\\\ Cov(\\sigma_{n1}) &amp; Cov(\\sigma_{n2}) &amp; \\dots &amp; Var(\\sigma_{nn}) \\end{bmatrix}$ Somehow, I got the equation following some algebraic steps, but I can't see how this part, $\\dfrac{1}{n}\\sum_{i=1}^n(x_i-\\mu)(x_i-\\mu)^T$, works and produces the covariance matrix. Hope to hear some explanations.", "What do \\makeatletter and \\makeatother do? Many LaTeX “hacks” begin with \\makeatletter and end with \\makeatother. What do these commands do?", "Creating node shapes", "In Dreamweaver typing &lt;/ will automatically close the last open tag, so you don't have to type it all out, and it helps if you aren't sure if you closed one or not. Is there a plugin that dose this for Notepad++? This is not like text FX where typing the opening tag/bracket adds the close on the other side of the cursor. This behavior is an auto completion that happens when &lt;/ is typed, DW finds whatever the innermost open tag is, and closes it. I find that, when I have the option of using DW, I will use this feature far more often than anything else that DW provides. Thus I would love to know if there was a way to do it in NPP. Here is DW preference in question: Notice how there is a different option that does what text FX does, but I don't want that. I am not opposed to unorthodox suggestions, some kind of macro, or hack of a plugging. Anything to emulate the functionality. If need be, I could write a plugin, I just have no idea how to go about it.", "How do I get a selected vertex and it's corresponding uv vertex? A vertex I can get with bpy.context.active_object.data.vertices[0] A uv vertex I can get with bpy.context.active_object.data.uv_layers['UVMap'].data[0] But the index is not the same for uv and mesh vertex.", "Allow moderators to edit/delete comments directly from the per-user comment moderation page A while back, a new dashboard was added to the user moderation tools to . It's great for scouring a user's comment history to find certain comments, but I can't do anything from this dashboard except filter by flagged1, deleted, or active comments, and visit the posts to which the comments are attached where I can then edit or delete them. Can we have the ability to edit and delete comments from this dashboard just as we're able to from the flag queue? It gets particularly tedious to have to open 100 tabs just to delete 100 spam comments from the posts they're attached to (and no, I'm not making that number up2...). 1 . 2 Alright, fine, I made that up; the actual number of spam comments I had to delete was 111.", "I have a directory that contains the following: x.pdf y.zip z.mp3 a.pdf I want to delete all files apart from x.pdf and a.pdf. How do I do this from the terminal? There are no subdirectories so no need for any recursion.", "How do I prove the following statement by induction? $$n^2 \\lt 2^n$$ $P(n)$ is the statement $n^2 \\lt 2^n$ Claim: For all $n \\gt k$, where $k$ is any integer, $P(n)$ (since $k$ is any integer, I assume I have to prove this for positive and negative integers) So let base case be $P(1)$, and I have to prove $P(n)$ for $n \\ge 1$ and $n \\lt 1$ $P(1)$ is $1^2 \\lt 2^1$ which is clearly true. Induction hypothesis: $k^2 \\lt 2^k$ Inductive step $(k+1)^2 \\lt 2^{(k+1)}$ $(k+1)^2 = k^2 + 2k + 1$ $k^2 + 2k + 1 \\lt 2^k + 2k + 1$ by inductive hypothesis Not sure how to proceed. Is my previous intuition that I have to prove this for $n \\ge 1$ and $n \\lt 1$ correct?", "Can't change font size for GD imagestring()", "How to uninstall broken programs in windows 7 Could anyone tell me how to uninstall programs that their installation had a problem and therefore their uninstall doesn't work? I removed all their references in the registry and their folder on the hdd but still don't know how to get rid of them completely from Add/Remove Programs list. Thanks", "Suppose $k$ is a field that is finitely generated as a ${\\mathbb Z}$-algebra. (That is, $k$ is a quotient of ${\\mathbb Z}[X_1,\\dots,X_n]$ for some $n$). Does it follow that $k$ is finite?", "Javascript profanity match NOT replace", "It has been discussed before, but in light of some of the , I can't help but wonder what is accomplished by displaying the author of a given question or answer. There is a , but if anything, I don't think it goes far enough. If questions and answers are supposed to stand on their own merit, why do we need to show the author at all? I'm not proposing any change to the way rep works; rep should still be accrued and abilities gained. The only difference is that questions and answers would appear anonymous. Does this better reflect the goals of SO? If so, how far do you think the anonymity should be taken? If not, what shortcomings am I missing?", "I'm getting frequent inaccurate location as the same location, can I make this stop?" ]

[ "I was wondering what the proper LaTeX code would be to display something like this: You don't have to include the mathematical symbols, what is important is the structure.", "Given a logarithm is true, if and only if, $y = \\log_b{x}$ and $b^y = x$ (and $x$ and $b$ are positive, and $b$ is not equal to $1$), are true, why aren't logarithms defined for negative numbers? Why can't $b$ be negative? Take $(-2)^3 = -8$ for example. Turning that into a logarithm, we get $3 = \\log_{(-2)}{(-8)}$ which is an invalid equation as $b$ and $x$ are not positive! Why is this?", "Should I follow what was mentioned in the “duration of stay” or in the \"validity of the visa\"? I'm from Tunisia and I got a Schengen visa from the Austrian Embassy for 28 days, the “duration of stay”, and the number of entries is 1. But the validity of the visa is from 02/08/2015 to 13/09/2015. Do I have to stay only 28 days, for example from 02/08/2015 to 29/08/2015 or can I stay there until 12/09/2015 ? And if I have got to stay only 28 days, then can I choose the days of stay, that's mean can I stay in Austria for example from 09/08/2015 to 05/09/2015?", "Find the number of solutions of $x^2=x\\mod m$ for any integer $m$. I was thinking about bringing the $x$ over to the other side and somehow apply chinese remainder thm.", "Do I have to buy a second wildcard certificate for a subdomain? We already have a wildcard certificate for *.mycompany.com. Our network has hosts that are only reachable internally. All of them belong to the internal.mycompany.com subdomain. There is a private server with the host name server.internal.mycompany.com on which I deployed our wildcard certificate. When I visit the web server I get a host name mismatch error. Do I really have to get another wildcard certificate for *.internal.mycompany.com or is there another (free!?) way to use our wildcard certificate for all of our subdomains and its subdomains without getting an error in the browser?", "Why do we use Root Mean Square (RMS) values when talking about AC voltage What makes it a good idea to use RMS rather than peak values of current and voltage when we talk about or compute with AC signals.", "Why is cd not a program?", "Is the universe isomorphic to a universal turing machine? I often think about problems that require an understanding of the very essence of computation and its inherent limitations. So, my questions are as followed: Is the universe isomorphic to a universal turing machine? Is the universe isomorphic to a universal quantum computer? What evidence do we have within our universe to support an answer to such a question? What corollaries follow from a universe that is or is not isomorphic to a universal turing machine (or universal quantum turing machine)? Is this question really answerable, and what is the current literature on this subject? I'm mostly interested in the implications and corollaries that follow from a universe that is or is not isomorphic to a turing machine (or universal quantum computer) and the insights that it would provide us with, about the nature of computation.", "Can I get back my saved data?", "Changing affiliation on publication", "Find Nearby Accounts migration to Google Maps API v3", "How to debug hadoop mapreduce jobs from eclipse?", "Effectively creating this effect in Illustrator? Been lurking awhile but this is my first post. I've always wondered what this effect is called and I'm almost certain there's an easier way to doing it than how I do it. I'm talking about the \"empty\" stroke around overlapping parts of icons. In this case I would put a stroke that's the color of the background around the first character. I know this is bad practice for many reasons, but I haven't found a way to use the pathfinder to do this. I'm looking for a way to do it that would effectively cut away the shapes smoothly in a X amount of pixels around a certain shape instead of covering it up so I can save the icon and use it over whatever colored background I want to. I'm guessing I'm not the first person to ask this but I have no earthly clue how this effect is called so my research has returned nothing relevant.", "How do you mock a Sealed class?", "In C++/CLI, what does the hat character ^ do? I was reading Ivor Horton's Beginning Visual C++ 2008 and many of its CLR examples have this definition for main: int main(array&lt;System::String ^&gt; ^args) I went back, page by page, to the beginning of the book to find the first such instance with an explanation what it really means, but couldn't find one. Obviously it means the same as the standard int main(int argc, char *argv[]), but I'd like to know when and why that ^ is really used, and why it even exists (does it do something that pointers * and references &amp; cannot represent)?", "Associativty of smash product on compact spaces Let $Y,Z$ be compact or $X,Z$ locally compact. Then the canonical bijection $$ (X \\wedge Y) \\wedge Z \\rightarrow X \\wedge (Y \\wedge Z) $$ is a homeomoprhism. I can prove the case when $X,Z$ are locally compact using exponential law. But I don't see how one approaches the case when $Y,Z$ compact. Hints?", "Where to upload too big files? I have a big HTML file that causes no errors in most of the browsers. However, when I open it with, let's say, Google Chrome, the program shuts down and I cannot trace why this is happening. This HTML file is quite big and cannot be posted to a question in SO, but it should be ran as a whole as I cannot trace where the problem is. What is/are the most appropriate file upload website/s to upload and paste the link into the question?", "Please help identify this 2-part TV movie: Alien woman crash-lands on earth, falls in love, 199x", "What is the name of the depiction of concentration with raised eyebrow called?", "How to add \"Refresh\" option to right click menu in Lubuntu? I have many users at the place I work, expressing the notion of switching to Ubuntu. Most of them, for whatever weird reason wanting to know if its possible to have refresh added when you right click on the desktop. Is that possible?" ]

[ "Let $p$ be prime and $(\\frac{-3}p)=1$. Prove that $p$ is of the form $p=a^2+3b^2$ Let $p$ be prime and $(\\frac{-3}p)=1$, where $(\\frac{-3}p)$ is Legendre symbol. Prove that $p$ is of the form $p=a^2+3b^2$. My progress: $(\\frac{-3}p)=1 \\Rightarrow$ $(\\frac{-3}p)=(\\frac{-1}p)(\\frac{3}p)=(-1)^{\\frac{p-1}2}(-1)^{\\lfloor\\frac{p+1}6\\rfloor}=1 \\Rightarrow$ $\\frac{p-1}2+\\lfloor\\frac{p+1}6\\rfloor=2k$ I'm stuck here. This is probably not the way to prove that. Also tried this way: $(\\frac{-3}p)=1$, thus $-3\\equiv x^2\\pmod{p} \\Rightarrow$ $p|x^2+3 \\Rightarrow$ $x^2+3=p\\cdot k$ stuck here too. Any help would be appreciated.", "Is it possible to colour or put textures on Bevel curves? So with my model, I've been struggling to create hair because it always looked weird or off and recently I discovered the \"Bevel Curve\" addon and it's an absolute lifesaver. So I converted the bevels into mesh to colour it, except it lags blender like crazy and I need this model for a video game I'm currently developing called Candles(so I can't upload the model, sorry) but I was wondering, is it possible to put a texture on a bevel curve like you would mesh or any other method or giving it colour?", "Estimate the population variance from a set of means", "Would you please explain the difference between these two sentences? Spain ceded (or gave) Puerto Rico to the United States. Since then, Puerto Rico has been a U.S. territory. Spain ceded(or gave) Puerto Rico to the United States. Since then, Puerto Rico was a U.S. territory. I am stuck between 'has been' and 'was' in the above sentences.", "I'm using Apache JMeter 2.3, which now supports \"attempt HTTPS spoofing\" under the Proxy Server element. I've tried this on several different servers, and have had no success. Has anyone been able to successfully record from an HTTPS source with this setting? Or barring successfully recording, can anyone share a work-around? When available, I simply have HTTPS turned off at the server level, but this is not always feasible. Thoughts?", "Can store bought salmon be used for sashimi? Is it safe to consume raw fish purchased at the fish counter of a typical suburban grocery store? If not, do you have any tips for finding sushi grade fish. Also, are there requirements for safe sushi/sashimi beyond the use of safe fish?", "How to burn a Windows .iso to a USB device? I want to burn a Windows ISO to a USB device in Ubuntu. How do I do this? I know how to burn a Ubuntu ISO into a USB device, but with a Windows ISO it's not the same.", "How to find and return a duplicate value in array", "Suppose $A$ is a $n \\times n$ constant matrix. How can I prove $\\det(e^A) = e^{\\displaystyle \\sum_{\\lambda_i\\in\\sigma(A)} \\lambda_i}$, where $\\sigma(A)$ is the multiset of eigenvalues of $A$? The following matlab code shows this is true in $n = 3$ case: A = rand(3) detA = exp(sum(eig(A))) detmA = det(expm(A))", "In Java, how do I convert a byte array to a string of hex digits while keeping leading zeros?", "A question about the idea of Laplace transform In Laplace integral transform equation one multiplies the function $f(t)$ by $e^{-st}$. I read in many tutorials that $e^{-st}$ decays much faster than any other function so the integral diverges. But what I don't understand what makes one to think to multiply a function with $e^{-st}$ to transform it in $s$ domain? What is the motivation behind it? Why would you suddenly come up with an idea as such: \"Oh there is a function $f(t)$ in time domain what can I do to transform it to complex freq. ($s$) domain? Hmm let me multiply it with $e^{-st}$ and integrate it from zero to infinity\" What would have motivated this idea of multiplying and integrating for transformation?", "Consider the smallest number in each of the $n\\choose r$ subsets (of size $r$) of $S=\\{1,2,\\ldots,n\\}$... Consider the smallest number in each of the $n\\choose r$ subsets (of size $r$) of $S=\\{1,2,\\ldots,n\\}$.Show that the arithmetic mean of the numbers so obtained is ${n+1}\\over{r+1}$. I have no idea, how to solve it.It would be better if the solution has bijection. Please help!", "Why more (and varying number of) logical reads with read ahead (prefetch)? After creating tpch database in my SQL Server, I tried below query: set statistics io on DBCC DROPCLEANBUFFERS; select top 100 * from dbo.lineitem order by l_partkey; The table lineitem has a non-clustered index on l_partkey. I issued the above queries for several times and found out that the logical reads vary each time: Table 'lineitem'. Scan count 1, logical reads 1019, physical reads 4, read-ahead reads 1760, lob logical reads 0, lob physical reads 0, lob read-ahead reads 0. Table 'lineitem'. Scan count 1, logical reads 1007, physical reads 4, read-ahead reads 1720, lob logical reads 0, lob physical reads 0, lob read-ahead reads 0. Table 'lineitem'. Scan count 1, logical reads 1030, physical reads 4, read-ahead reads 1792, lob logical reads 0, lob physical reads 0, lob read-ahead reads 0. From the post here: , I know it could be caused by read ahead behavior. BUT exactly why read ahead could cause more logical reads? How does it change the SQL Server behavior? Like SQL Server may read more index page since it's in cache anyway? Anyway, I disabled read ahead and issue the above query again. Now it reports the same amount of logical reads each time. BUT the logical reads is much smaller!! Table 'lineitem'. Scan count 1, logical reads 404, physical reads 160, read-ahead reads 0, lob logical reads 0, lob physical reads 0, lob read-ahead reads 0. So my question is, why the read ahead feature could cause many more and various logical reads count? Out of curiosity, I tried another query without the \"order by\": select top 100 * from dbo.lineitem Here's the result without read ahead: Table 'lineitem'. Scan count 1, logical reads 5, physical reads 3, read-ahead reads 0, lob logical reads 0, lob physical reads 0, lob read-ahead reads 0. Here's the result with read ahead: Table 'lineitem'. Scan count 1, logical reads 15, physical reads 2, read-ahead reads 3416, lob logical reads 0, lob physical reads 0, lob read-ahead reads 0. The one with read ahead still has more logical reads. So, why?", "How can I SELECT rows with MAX(Column value), PARTITION by another column in MYSQL?", "Passing a varible from jQuery to PHP", "I just learned that using CBC encryption with an IV which is predictable is not secure. From what I understand, using certain plain texts, and then guessing the IV that it uses, the attacker can verify if the IV he guessed was right. How does this qualify as an attack?", "Is there a license / royalty free DRM available for protecting and distributing video content?", "Can CBC ciphertext be decrypted if the key is known, but the IV not?", "How can one prove that $\\lim_{n \\to \\infty}a^{1/n}=1$ for every $a>0$?", "$f(x)=x/1$ is not injective? In chapter 3 of Atiyah and Macdonalds Intro to Comm Algebra there is the statement \"We also have a ring homomorphism $f:A\\rightarrow S^{-1}A$ defined by $f(x)=x/1$. This is not in general injective.\" (Note: $A$ denotes an integral domain and $S$ a multiplicatively closed subset of $A$.) How could this possibly not be injective? If $f(x)=f(y)$ then $x/1=y/1$ so $1x=1y$ hence $x=y$. What am I missing here?" ]

[ "Restrictions on the variables for this identity are as follows: $a \\geq m \\geq 0$ and $n \\geq b \\geq 0$. I have not gotten far with this, but these are my very rudimentary thoughts: We need to define a special element, somehow, and then carve up the $m + n$ remaining elements to be chosen out of the remaining pool of $a + b$ elements by writing $a + b = a - i + b + i$. From the $a - i$ pile, we choose $m$ things. From the $b + i$ pile, we choose $n$ things. My problem is, what is going on with this special element? How is it being defined so as to split things in this precise way? A hint would be great for the moment.", "Inequality: $ab^2+bc^2+ca^2 \\le 4$, when $a+b+c=3$. Let $a,b,c $ are non-negative real numbers, and $a+b+c=3$. How to prove inequality $$ ab^2+bc^2+ca^2\\le 4.\\tag{*} $$ In other words, if $a,b,c$ are non-negative real numbers, then how to prove inequality $$ 27(ab^2+bc^2+ca^2)\\le 4(a+b+c)^3.\\tag {**} $$ $\\color{gray}{\\mbox{(Without using \"universal\" Lagrange multipliers method).}}$ Thanks!", "The portion of the tangent to any conic intercepted between the point of contact and the directrix subtends a right angle at the focus of the conic?", "I'm having a bit of trouble proving this with the propositional calculus rules. $$p \\lor (p\\implies q)$$ Would someone mind helping me and showing which rules they've used with an explanation! Thanks!", "How to reset Canon 70D WiFi? When I go to the WiFi Settings in Camera (Canon 70D) all I see is: Connection: Exit Confirm Set Error Details (greyed out) I can't recall the password or find any way to reset it. Some I found () say the Camera should say Infrastructure mode. Inside the Confirm Settings I can see on page 3 it shows: Connect'n method: Camera access point mode But again I see no way to change this. On my Smartphone EOS Remote app there's a Connection Guide with completely different menus from what I'm seeing on the Camera. Any idea how I can reset the WiFi Name and Password on the Canon 70D?", "Prove that there exists some $c\\in(-3,3)$ such that$ \\ \\ g(c) \\cdot g''(c)<0$. $f(x)$ is a differentiable function and $g(x)$ is a double differentiable function such that $|f(x)|\\leqslant 1$ and $f'(x)=g(x)$. If $$f(0)^2+g(0)^2=9$$ then prove that there exists some $c\\in(-3,3)$ such that$ \\ \\ g(c) \\cdot g''(c)&lt;0$. Attempt: Let us define a function $h(x) = g(x) g~'(x)$. Then $$h'(x) = g(x)g''(x) + \\left( g'(x) \\right)^2 \\tag 1$$ If we prove that for some $c \\in (-3,3), h~'(c) &lt; 0,$ then $$g(c)g''(c) &lt;0 \\tag 2$$ Also, $$\\left|f(0)\\right| &lt; 1 \\implies f'(0) \\in (-3,-2\\sqrt 2 ) \\cup (2\\sqrt 2,3) $$ Could someone please advise me how do I move forward from here. Thank you very much for your help in this regard.", "The future of meta.stackoverflow and meta.stackexchange Historically this site, , has been the place to ask questions about not just Stack Overflow, but the functioning of the entire Stack Exchange (2.0) network, including Area 51 and stackexchange.com and careers. (Yes, there was a , but that dealt with the old legacy Stack Exchange 1.0 sites. It was deprecated a while ago, and currently redirects here.) Now that we've gotten many, many months under our belt from the SE 1.0 days, I think it's time that we gave Stack Overflow its own, true per-site meta, and moved the higher level network meta discussions to meta.stackexchange.com. Over time, it's begun to bug me more and more that requests for Stack Overflow, the site, kind of get buried here on meta.stackoverflow under the avalanche of network issues. Retag requests, synonym requests, things truly specific to Stack Overflow, the site, not the network. This is unfair to our vastly largest and flagship Q&amp;A site, and it's unfair to the Stack Overflow users to mix their requests in with network level concerns. It's also odd that Stack Overflow is the only network site without a proper, dedicated per-site meta, where its meta has its own reputation system not tied to the parent site in any way. This is mostly a quirk of history more than anything else, and I believe it is now an appropriate time to split into two sites: , a proper per-site meta for Stack Overflow with integrated rep , a global network meta with its own reputation system Yes, this will be painful. But I believe it is a good, necessary, and healthy step both for the future of the network and the future of Stack Overflow. Some things to discuss: which questions should be migrated from here to meta.so? Obviously site-specific things like the retag-requests, and perhaps questions with the tag. Anything that is 100% wholly specific to Stack Overflow and not generalizable to the rest of the network should be moved over. This may be a pretty small, narrow list of questions, and that's OK. Should we do some meta spring cleaning in our transition? Which questions / tags should be blown away as no longer relevant, referring to ancient versions of Stack Overflow or issues that have long since ceased to exist and aren't instructive for any future visitors? Your meta reps will generally be unaffected, except insofar as we delete for spring cleaning, or move site-specific things to meta.so. We still plan to have a distinct reputation system for the new meta.se site, just like here. I do not have a timeline for this change, that is up to Jarrod and David to decide. It may be months away. However, we feel pretty strongly that this is something that we need to do to clean things up and pave the way for the future -- so I expect it will happen in the next few months, giving us lots of time to decide how we want to do it, per the above. Update .", "How large would the steam explosion at Chernobyl have been? So the of the HBO series began to cover the that led to them sending three divers into the water below the reactor to drain the tanks. This occurred after the initial explosion that destroyed the reactor, and after the fire in the core had been put out. But at this point the decay heat and remaining fission reaction kept the core at more than 1200°C, causing it to melt through the concrete floors below the reactor. And below the reactor were water tanks which contained 7,000 cubic meters of water (according to the TV show. If anyone has a real figure, I'd love to hear). When the lava of the melted core hit it, it would cause an enormous . Finally, my question: About how large would this explosion have been? The character in the show says \"2-4 megatons\" (of TNT equivalent, I assume). I'm pretty sure this is absurd and impossible. But real estimates are hard to come by. Other sources vary wildly, some repeating the \"megatons\" idea, and others saying it would've \"\". This still seems crazy. tl;dr: I know a lot of it hinges on unknowns and the dynamics of the structures and materials involved, so I can simplify it to a constrained physics question: Assuming 7,000 cubic meters of water instantly flashes to steam, how much potential energy is momentarily stored in that volume of steam occupying the same volume as the water did? I don't know what to assume the temperature of the steam is. There were hundreds of tons of core material at temperatures near 1200°C, so worst case scenario you could assume all the steam becomes that temperature as the materials mix. Best case scenario, I guess we could assume normal atmospheric boiling point (100°C)?", "$$\\frac{1}{z-\\sin z}$$ $$\\frac{1}{z(1-\\frac{\\sin z}{z})}$$ the laurent's transform is also used to simplify the function. the residue is found a $\\frac{2*36*2}{5}$ but the actual answer is given as $\\frac{3}{10}$ the residue is given as The solution is incorrect and also the pole is of the order 3.", "How to load a taxonomy term with case-sensitive? I used this $this-&gt;termStorage-&gt;loadByProperties(['name' =&gt; 'test']); I got two terms: Test, test. I want to get only one: test This is working without case-sensitive: $this-&gt;termStorage-&gt;getQuery()-&gt;condition('name', 'test', '=')-&gt;execute(); \\Drupal::database()-&gt;select('taxonomy_term_field_data', 't') -&gt;condition('t.name', 'test') -&gt;fields('t', ['name']) -&gt;execute() -&gt;fetchAll(); \\Drupal::database()-&gt;query(\"SELECT name FROM taxonomy_term_field_data WHERE name='test'\")-&gt;fetchAll();", "Conditions: do not modify the original lists; JDK only, no external libraries. Bonus points for a one-liner or a JDK 1.3 version. Is there a simpler way than: List&lt;String&gt; newList = new ArrayList&lt;String&gt;(); newList.addAll(listOne); newList.addAll(listTwo);", "Short story about survivors on Earth after the atmosphere has frozen This is a short story I read maybe in the '80s. Earth has been thrown away from the Sun, probably due to a very large object passing through the Solar System, and the atmosphere has frozen in layers. There is a small family - father, mother, two children, who live in a room they have made airtight by hanging many layers of material to slow the loss of air. They keep warm with a 'camp-fire'. The father goes out every day in a suit of some sort to find food and mine frozen oxygen. It ends when they are found by another, larger group of survivors. Does anybody know the title and author?", "Inequality involving sides of a triangle How can one show that for triangles of sides $a,b,c$ that $$\\frac{a}{b+c}+\\frac{b}{c+a}+\\frac{c}{a+b} &lt; 2$$ My proof is long winded, which is why I am posting the problem here. Step 1: let $a=x+y$, $b=y+z$, $c=x+z$, and let $x+y+z=1$ to get $\\frac{1-x}{1+x}+\\frac{1-y}{1+y}+\\frac{1-z}{1+z}&lt;2$ Step 2: consider the function $f(x)=\\frac{1-x}{1+x}$, and note that it is convex on the interval (0,1), so the minimum of $\\frac{1-x}{1+x}+\\frac{1-y}{1+y}+\\frac{1-z}{1+z}$ is reached when the function takes the extreme points. i.e. $x=y=0, z=1$. But going back to the fact that this is a triangle, we note that $x=y=0 \\implies a=0$ which is not possible, so the inequality is strict.", "I am studying elementary Algebraic Topology recently. I have seen that a topological space is identified with a group. We are telling the group as Fundamental Group. So every topological space $X$ and for any $x \\epsilon X$ there is a fundamental group $\\pi_1 (X,x)$. I have a question about the converse. If we consider any arbitrary group $G$, then does there exist a topological space $X$ and an element $x\\epsilon X$ such that $\\pi_1 (X,x)=G$?", "Why are Bitmap-Fonts used automatically? I have the following LaTeX-document: \\documentclass[a4paper,11pt]{article} \\usepackage[utf8x]{inputenc} \\usepackage[ngerman]{babel} \\usepackage[T1]{fontenc} \\title{Sample} \\author{Litb} \\begin{document} \\maketitle \\begin{abstract} This is a report about my praxis phase at the company foo bar which I enjoyed. \\end{abstract} \\end{document} Much to my frustration, compiling with pdflatex creates a document with Bitmap-fonts. The reader's font-list shows that it uses Type3 fonts. If I remove the fontenc loading, then I get a PDF using vector-fonts, but I heard that I should keep it, for having native German Umlauts working. Does anyone know how I can get vector fonts with T1, and why it keeps using bitmap fonts if I have that package-load line in it?", "A coin is tossed $n$ times. What is the probability of getting odd number of heads? I started this chapter sometimes ago and faced in front of a tough problem. At first I started considering cases. Case-I : The probability of getting 1 head.Case-II : The probability of getting 3 head and so on. But there are many cases. So how can I solved this . Please help me. Thank you!", "What prevents photons from getting mass from higher order Feynman diagrams The Higgs boson and gluons have no electric charge and photons couple to charge, so there is no tree level interaction between them and photons. But what prevents higher order diagrams from contributing a non-zero mass term to the photon, for instance where a photon couples to some fermion (say an electron, or a top quark) which can interact with the Higgs field. Or consider that same diagram but with quarks and a gluon interacting between them? Or any higher diagram with even more loops? I have heard charge conservation depends on gauge invariance, which in turn depends on photons being massless. So it appears the photon has no mass, and these diagrams must all cancel somehow. So I'm hoping there is a very nice symmetry explanation for why they all disappear, but if I say \"because of gauge invariance\" that would be circular logic, so there must be another symmetry at stake here? What prevents photons from obtaining a mass from high-order self-energy loop diagrams?", "What is $\\sum_{r=0}^n \\frac{(-1)^r}{\\binom{n}{r}}$? Find a closed form expression for $$\\sum_{r=0}^n \\dfrac{(-1)^r}{\\dbinom{n}{r}}$$ where $n$ is an even positive integer. I tried using binomial identities, but since the binomial coefficient is in the denominator, I can't do much. Also, I'm seeking a non-calculus, elementary solution, if possible. Thanks.", "I understand that there is an upper limit. But why do you have to type at least 15 characters to post a comment? It is easy to work around it anyway (like adding dots or other useless things).", "Children’s books, one in space setting, the other in a jungle When I was little I remember getting these two books from the library. Both books were paperback and flimsy. The pages were wide. Each book had full page illustrations with puzzles and mazes in them, but it was like you were immersed in this setting completely. They were also like choose-your-own adventure books, but only in the way that you go through the book in a different order based on your results in the puzzles/games. For example, there is a bridge to cross, or you can take this path. If you choose to cross the bridge you go to page x. On page x you have to pretend to cross the bridge but some planks are broken. You can't skip more than a certain number of planks, but you also cannot \"step\" on a broken plank. One book was in a jungle setting with rope bridges, alligators, quick sand, etc. The other was in space, with all kinds of aliens and weird stuff. I have faint memories of these books but I REALLY want to track them down because I remember loving them." ]

[ "According to , gold badge holders can now unilaterally close questions as duplicates. I hold seven gold badges for tags on SO, which means I can, on my own, close questions as duplicates for those tagged questions. Simply put: DO NOT WANT. However, I do not see any ability in SO (the only SE site I spend much time in) to opt out of any privileges, let alone this one. Is there a spot that I'm just not seeing that allows me to turn off this new privilege?", "Splitting a PDF document in two without purchasing a PDF editing tool Acrobat Reader allow us to easily save a copy of the PDF document. How can I save only from page 5 to 10 without purchasing a PDF editing tool?", "My dad has an old Sears KS-2 + 50mm f/1.7, which from a bit of research seems to use a Pentax K-mount. I've looked around a bit and found a , which says it supports af-confirmation, and costs ~$30 US. Has anyone tried using an adapter ring like this, and if so, would you recommend doing so? I am perfectly happy with shooting manual, but I'm curious about the quality of older lenses. I'm assuming that if I use older primes the optical quality will be fine, and it looks like the build quality of the older lenses is much better that similarly priced new lenses.", "Where exactly does energy quantisation come in for light? Planck quantised the energy of light in order to solve the black body radiation problem. However, I am confused as to exactly what he quantised. On one hand, I have seen that he quantised the energy of oscillators in the black body (source below). However, the second version of the story I've heard is that it is simply that light energy is given off in discrete chunks (where every photon itself can have any value of energy it likes depending on frequency and is not quantised). To me, the first idea doesn't make sense because $E=hf$ and as $f$ can be any real number that means the energy of each photon can be any real number. I would believe the second version, however I don't understand how this version of quantisation leads to reducing the number of high frequency waves emitted and thus solving the UV catastrophe. Could you please explain exactly how releasing energy in chunks (of arbitrary size themselves) means less will be released in the higher frequencies?", "Alert on edit after a downvote", "Use induction to prove a product of sums of squares is a sum of squares", "Possibility of recovering files from a dd zero-filled hard disk I have \"zero filled\" (complete wiped) an external hard disk using dd, and from what I have heard: people said you should at least \"zero fill\" 3 times to be sure that the data are really wiped and no one can recover anything. So I decided to scan the disk once again after I've zero filled the disk. I was expecting the disk to still have some random binary left. It turned out that it has only a few sequential bytes in the very beginning. This is probably the file structure type and other headers stuff. Other than that, it's all zeros and nothing else. So if we have to recover any file from a zero filled disk, ...how? From what I've heard, even you zero fill the disk, you should still have some data left. ...or could dd really completely annihilate all data?", "Creating System-Wide Keyboard Shortcut To Launch Applications I recently switched from Ubuntu, and I was feeling very comfortable with using Ctrl + Alt + T to launch terminal. Can I assign Shift + Cmd + T to do the same thing in Yosemite? Specifically, I want a new terminal window to be opened.", "Trim string in JavaScript?", "Linear Discriminant Analysis for $p=1$ I'm studying 'Introduction to Statistical Learning' by James, Witten, Hastie, Tibshirani. In page 139, of their book, they began by introducing Bayes' Theorem $p_k(X)=P(Y=k|X=x) = \\dfrac{\\pi_kf_k(x)}{\\sum_{l=1}^k \\pi_l f_l(x)}$. $\\pi$ is not mathematical constant, but denotes the prior probability. Nothing is strange in this equation. The book claims that it wants to obtain an estimate for $f_k(x)$ that it can plug into the equation given above. To estimate $f_k(x)$, it assumes that is normal. In the one dimensional setting, $f_k(x)=\\dfrac{1}{\\sqrt{2\\pi}\\sigma}\\exp(-\\dfrac{1}{2\\sigma^2}(x-\\mu_k)^2)$, where $\\mu_k$ and $\\sigma^2_k$ are the mean and variance for the $k$th class. It is assumed that $\\sigma^2_1 = \\sigma^2_2 = \\cdots = \\sigma^2_K$. (I began to get confused from the last statement.) Plugging $f_k$ into $p_x$, you have this quite messy equation (1) : $$p_x(k)=\\dfrac{\\pi_k \\frac{1}{\\sqrt{2\\pi}\\sigma}\\exp(-\\frac{1}{2\\sigma^2}(x-\\mu_k)^2)}{\\sum_{l=1}^K \\pi_l \\frac{1}{\\sqrt{2\\pi}\\sigma}\\exp(-\\frac{1}{2\\sigma^2}(x-\\mu_l)^2)}. $$ Again, no surprises here since it is just substitution. The Bayes' Classifier involves assigning an observation to the class for which equation (1) is the largest. Taking the log of Equation (1) and rearranging terms, it is not hard to show that this is equivalent to assigning the observation to the class for which the following is the largest: $$\\delta_k(x)=x \\cdot \\dfrac{\\mu_k}{\\sigma^2} - \\dfrac{\\mu_k^2}{2\\sigma^2} + \\log(\\pi_k) $$ Question: I do not understand where this came from, and what it means. I tried doing the log of equation and it doesn't become this. Are we taking the derivative somewhere here, since this is the largest observation?", "Is Canon 60D still a decent camera? I have a Canon 60D, bought it back in 2013. Use it quite a while, but in past two-three years, I lost interest in photography. I will be going on a long trip this summer and would like to take a decent camera with me. Is Canon 60D still a decent one or I will be missing on features and upgrades comparing to the latest versions? In terms of lenses I own Tamron 24-70 2.8 And Canon 100 2.8 Macro.", "Why do Tcler suggest to brace your `expr`essions?", "Suppose $ \\alpha, \\beta&gt;0 $. Compute: $$ \\int_{0}^{\\infty}\\frac{\\cos (\\alpha x)-\\cos (\\beta x)}{x}dx $$ Here is what I do: $$\\begin{align} \\int_{0}^{\\infty}\\frac{\\cos (\\alpha x)-\\cos (\\beta x)}{x}dx &amp;= \\int_{0}^{\\infty}dx\\int_{\\alpha}^{\\beta}\\sin (yx)dy\\\\ &amp;=\\int_{\\alpha}^{\\beta}dy\\int_{0}^{\\infty}\\sin(yx)dx\\\\ &amp; \\\\ &amp; \\qquad\\text{let $ yx=u $}\\\\ &amp; \\\\ &amp;=\\int_{\\alpha}^{\\beta}\\frac{1}{y}dy\\int_0^{\\infty}\\sin u du\\\\ &amp;=\\int_{\\alpha}^{\\beta}\\frac{1}{y}dy\\left( -\\cos u|_{\\infty}+\\cos u|_0 \\right)\\\\ &amp;=\\log\\frac{\\beta}{\\alpha}(-\\cos(\\infty)+1)\\\\ &amp;=\\log\\frac{\\beta}{\\alpha}-\\cos(\\infty)\\log\\frac{\\beta}{\\alpha} \\end{align}$$ But $ \\cos(\\infty) $ does not exist right? Does it mean the integral actually diverse? Edit: The question comes from Who can point out my mistake in the above deduction?", "What's a word for lack of confidence?", "Use of each and every", "File issues after importing Drupal site I recently tried to move my Drupal site to a new server using this page: . But now the style doesn't seem be loaded and more importantly I get this error on every page in the site (even on the frontpage): Warning: file_put_contents(temporary://filef76T9k): failed to open stream: &quot;DrupalTemporaryStreamWrapper::stream_open&quot; call failed in file_unmanaged_save_data() (line 1900 of /Library/Server/Web/Data/Sites/Default/drupal/includes/file.inc). The file could not be created. Any ideas what this could be about?", "Detect the Internet connection is offline? How to detect the Internet connection is offline in JavaScript?", "\"None is\" or \"none are\" I was asked if the following sentences will create problems and what are the assumptions I have to make: (d) There are grammarians in the room but none of them is an American. (e) There are grammarians in the room but none of them are Americans. What is the problem in both sentences? They clearly have two main clauses which are connected by the coordinated conjunction 'but'. I know that grammar-wise, the 'is/are' don't really matter since both can be used with 'none', but would the tense in the first main clause 'are' affect the use of 'none'?", "What are the criteria used to represent Stack Exchange sites on the sites page? (Grid view) I noticed that has been changed, and by default sites are shown by balloons. What is not clear to me is why some sites are shown with a bigger balloon than other sites. For example, WordPress Answers has less questions, answers and users than Programmers, but its balloon is bigger. What are the criteria used to show the sites on that page?", "If $a, b, c$ be distinct reals such that $$a + \\frac1b = b + \\frac1c = c + \\frac1a$$ how do I find the value of $abc$? The answer says $1$, but I am not sure how to derive it." ]

[ "How do I insert the total continuation count in the allowframbreaks frame title? I would like to change the numbering of allowframbreaks frame, for instance, from I II III to (1/3) (2/3) (3/3)， but fail to find out a command to get the total continuation count. Here is the MWE. \\documentclass[compress]{beamer} \\usetheme{Warsaw} %allowframebreaks numbering in the title \\setbeamertemplate{frametitle continuation}{(\\insertcontinuationcount/)} %\\setbeamertemplate{frametitle continuation}{(\\insertcontinuationcount/\\inserttotalcontinuationcount)} \\title{title} \\author{author} %%%%% \\begin{document} \\begin{frame}[allowframebreaks]{allowframebreaks title} frame 1 \\framebreak frame 2 \\framebreak frame 3 \\framebreak \\end{frame} \\end{document}", "My stance is that these websites are a great boon to the research community and they were certainly extremely helpful for my research. I think they should be applauded rather than persecuted, and while they may be illegal now, I think a way to make them legal should be found (in the same way I can download articles legally through my university's subscription to all the major publishers and journals). Can I thank them in the acknowledgements section of my thesis?", "A field extension of prime degree Suppose that $E$ is an extension of $F$ of prime degree. Show that $~~\\forall~ a \\in E : ~ F(a)=F$ or $F(a)=E$ Attempt: Suppose that $E$ is an extension of a field $F$ of prime degree, $p$. Therefore $p = [E :F] = [E : F(a)][F(a) : F]$. Since $p$ is a prime number, we see that either $[E : F(a)] = 1$ or $[F(a) : F] = 1$. Now, $[E : F(a)] = 1 \\implies $ there is only one element $x \\in E$ which forms a basis and every element in $E$ is generated by $x$ i.e. $E = \\{x~c~|~ c \\in F(a)\\}$ $[F(a) : F] = 1 \\implies $ there is only one element $y \\in F(a)$ which forms a basis and every element in $F(a)$ is generated by $y$ i.e. $F(a) = \\{y~d~|~ d \\in F\\}$ Have I inferred it correctly? How do I move ahead? Thank you for your help.", "Do there Exist Proper Classes that aren't \"Too Big\" Some proper classes are \"too big\" to be a set in the sense that they have a subclass that can be put in bijection with $\\alpha$ for every cardinal $\\alpha$. It is implied in post that every proper class is \"too big\" to be a set in this sense, however I have been unable to prove it. It's true if every two proper classes are in bijection, but it's consistent with ZFC for there to be a pair of non-bijective classes. So, is the following true in ZFC: For all proper classes, $C$, and $\\alpha\\in\\mathbf{Card}$, $\\exists S\\subset C$ such that $|S|=\\alpha$? If not, is there something reasonable similar that preserves the intuition about classes that are \"too big to be sets\"?", "If $\\sum_na_n=\\infty$ and $a_n\\downarrow 0$ then $\\sum\\limits_n\\min(a_{n},\\frac{1}{n})=\\infty$ If $\\sum_na_n=\\infty$ and $a_n\\downarrow 0$ then $\\sum\\limits_n\\min(a_{n},\\frac{1}{n})=\\infty$ My idea: $$b_{n}=\\min(a_{n},\\tfrac{1}{n})\\Longrightarrow b_{n}\\le a_{n},b_{n}\\le\\tfrac{1}{n}$$ then I don't know how to go on.", "IBM Slack links broken", "Show that $(2,0,4) , (4,1,-1) , (6,7,7)$ form a right triangle What I tried: Let $A(2,0,4)$, $B(4,1,-1)$, $C(6,7,7)$ then $$\\vec{AB}=(2,1,-5), \\vec{AC}=(4,7,3), \\vec{BC}=(2,6,8)$$ Then I calculated the angle between vectors: $$\\begin{aligned} \\alpha_1 &amp;= \\cos^{-1}\\left(\\frac{(2,1,-5)(4,7,3)}{\\sqrt{2^2+1^2+(-5)^2}\\sqrt{4^2+7^2+3^2}}\\right) \\\\ &amp;= \\cos^{-1}(0)=90° \\\\ \\alpha_2 &amp;= \\cos^{-1}\\left(\\frac{(4,7,3)(2,6,8)}{\\sqrt{4^2+7^2+3^2}\\sqrt{2^2+6^2+8^2}}\\right) \\\\ &amp;= \\cos^{-1}\\left(\\frac{74}{\\sqrt{74}\\sqrt{104}}\\right)=32.49\\\\ \\alpha_3 &amp;= \\cos^{-1}\\left(\\frac{(2,6,8)(2,1,-5)}{\\sqrt{2^2+6^2+8^2}\\sqrt{2^2+1^2+(-5)^2}}\\right) \\\\ &amp;= \\cos^{-1}\\left(\\frac{-30}{\\sqrt{104}\\sqrt{30}}\\right)=122.5° \\end {aligned}$$ As you can see, these angles don't even form a triangle, what am I doing wrong, any thoughts?", "Would anyone can help me how to show that a finitely generated projective module over a local ring and PID are free? What I know about a finitely generated projective module $M$ over a PID $R$ is isomorphic to $R^k\\oplus R/(a_1)\\oplus\\dots\\oplus R/(a_n)$, and for the local ring case I don't know how to start.", "Evaluate $\\mathop {\\lim }\\limits_{x \\to 0} \\left( {{1 \\over {{{\\sin }^2}x}} - {1 \\over {{x^2}}}} \\right)$ I tried l'Hospital but that will require a lot (and I mean A LOT!!!) of differentiating Is there a shortcut? $$\\mathop {\\lim }\\limits_{x \\to 0} \\left( {{1 \\over {{{\\sin }^2}x}} - {1 \\over {{x^2}}}} \\right)$$ Thanks in advance", "Apex:OutputText to Currency Format from String Wrapper is there a way to pass a string to the &lt;apex:outputText&gt; so that it can be formatted as a currency or percent value? Here's what I have inside a column of my visual force table: &lt;apex:outputText value=\"{0, number, currecny}\"&gt; &lt;apex:param value=\"{!row.values[1]}\" /&gt; &lt;/apex:outputText this gives me an error at runtime (when the visual force page loads), which I think may be some kind of type mismatch, where &lt;apex:outputText&gt; is expecting a Decimal or number but I am passing a string. This is the error at runtime: The value attribute on is not in a valid format. It must be a positive number, and of type Number, Date, Time, or Choice. Thanks", "Can my friend and I play minecraft together with different mods? I'm wondering if I could play Minecraft with my friend. A modded Minecraft, only myself with mods and him without mods. Is it possible?", "Validity and Equivalence of two definitions of the real exponential function The Problem : We state the following two definitions of the real exponential function from the . We're interested in showing that the two definitions are valid $($i.e. the defining sequence/series does converge to a unique real number$)$ and that the two definitions are equivalent. I'm stuck at a couple of points $($which are described in highlighted lines$)$. Any help would be much appreciated. Thank you! Definition $1$. The exponential function can be defined as the following limit of a sequence $$\\exp x := \\lim_{n \\to \\infty} \\left({1 + \\frac x n}\\right)^n$$ Definition $2$. The exponential function can be defined as a $$\\exp x := \\sum_{n = 0}^\\infty \\frac {x^n} {n!}$$ My Progress and two places where I'm stuck : Essentially the solution consists of three parts, namely validity of definition $1$, validity of definition $2$ and equivalence of the two definitions. Validity of Definition $1$. I'm stuck here! Can we show that the sequence $(a_n)$ given by $a_n = \\left(1+\\frac{x}{n}\\right)^n$ converges for every $x \\in \\mathbb{R} ??$ Is it eventually monotone and bounded $??$ Validity of Definition $2$. The of the power series is $$r=\\lim_{n \\to \\infty}\\left| \\frac{\\frac{1}{n!}}{\\frac{1}{(n+1)!}} \\right|=\\lim_{n \\to \\infty}\\left| \\frac{(n+1)!}{n!} \\right|=\\lim_{n \\to \\infty}(n+1)=+\\infty$$ Thus the infinite series in the right-hand side of Definition $2$ converges to a unique real number for all $x \\in \\mathbb{R}$. Hence the definition is well-defined. Equivalence of Definition $1$ and Definition $2$. There's this of Definition $1$ $\\implies$ Definition $2$ in the Pr$\\infty$fWiki page, but it's kind of under construction and I'm not really convinced by it. So I decided to try to take my own shot at it. For all $n \\in \\mathbb{N} \\cup \\{0\\},$ let $$T_n=\\left(1+\\frac{x}{n} \\right)^n, ~S_n=\\sum_{k=0}^n \\frac{x^k}{k!}$$ We have to show that $\\lim_{n \\to \\infty} T_n = \\lim_{n \\to \\infty} S_n$ Now, \\begin{align} T_n &amp;= \\left(1+\\frac{x}{n}\\right)^n\\\\ &amp;= 1+n\\cdot\\frac{x}{n}+\\frac{n(n-1)}{2!}\\cdot\\frac{x^2}{n^2}+\\cdots +\\frac{n(n-1)\\cdots 1}{n!}\\cdot\\frac{x^n}{n^n}\\\\ &amp;= 1+x+\\left(1-\\frac{1}{n}\\right)\\cdot \\frac{x^2}{2!}+\\cdots +\\left(1-\\frac{1}{n}\\right)\\cdots \\left(1-\\frac{n-1}{n}\\right)\\cdot \\frac{x^n}{n!} \\end{align} Clearly, $$S_n-T_n=\\left\\{1-\\left(1-\\frac{1}{n}\\right)\\right\\}\\frac{x^2}{2!}+\\cdots +\\left\\{1-\\left(1-\\frac{1}{n}\\right)\\cdots \\left(1-\\frac{n-1}{n}\\right)\\right\\}\\cdot \\frac{x^n}{n!}\\geq 0$$ I'm stuck at this point. Can we show that $S_n-T_n \\leq B_n$ such that $B_n \\to 0$ as $n \\to \\infty ??$", "\"log in to\" or \"log into\" or \"login to\" When writing an instruction about connecting to a computer using ssh, telnet, etc., I'm not sure what spacing to use in this familiar spoken phrase: \"Log in to host.com\" \"Log into host.com\" \"Login to host.com\" Maybe this is entirely subjective or the realm of industry jargon, but I couldn't think of anywhere else to ask. Any insight?", "Strange artifacts along window borders after waking computer from sleep mode", "What should I do if I want to be able to run a given program regardless of my current directory? Should I create a symbolic link to the program in the /bin folder?", "Drawing a constant randomly distorted circle I am trying to draw a special and contradictive plot : A circle with random distortions which have to remain constant regardless of how many times I build the document. An example of what I am trying to achieve can be seen below This figure was produced with the following code \\documentclass{standalone} \\usepackage{tikz} \\usetikzlibrary{decorations.pathmorphing} \\begin{document} \\begin{tikzpicture} % axes \\draw[ultra thin] (-2.5, 0) -- (2.5, 0); \\draw[ultra thin] (0, -2.5) -- (0, 2.5); % undistorted sphere \\draw[ultra thin, dashed] (0, 0) circle (2.25cm); \\draw[ultra thin, dashed, -&gt;] (0:0) -- (125:2.25); \\node at (-1, 1) {$R$}; % distrorted sphere \\draw[very thick] plot[domain=0:350,smooth cycle ] (\\x:2+rnd*0.5); \\draw[very thick, -&gt;] (0:0) -- (45:2.1); \\draw[ultra thin, -&gt;] (1, 0) arc (0:45:1); \\node at (1.2, 0.4) {$\\theta$}; \\node at (0.7, 1.25) {$R(\\theta)$}; \\end{tikzpicture} \\end{document} The problem with the code is that whenever I make a change to it and rebuild the document, the \"distorted\" circle will have a different shape, since I am using the rnd function. The reason I would like to have a constant-random shape is because I would like to denote its radius at an angle θ, therefore it has to touch the outline of the circle. Any idea on how to achieve such a thing?", "Let's say I have a class that has a member called data which is a list. I want to be able to initialize the class with, for example, a filename (which contains data to initialize the list) or with an actual list. What's your technique for doing this? Do you just check the type by looking at __class__? Is there some trick I might be missing? I'm used to C++ where overloading by argument type is easy.", "Where does Drupal store its content? I have been currently learning Drupal while trying to duplicate a Drupal application into CakePHP. I have been looking at the database tables to know where data is being stored so I can safely migrate any data or study how it is working. I have researched and have come across questions like: So far, I have only seen the title in my Drupal (7) installation. What I have seen in my node revisions table for a recipe content type, which includes fields like, field_ingredients, field_instructions, field_description, field_preptime, field_cookingtime, just the title of the recipe. This is a sample record on my node_revision table. nid | vid | title | log | timestamp | status | comment | promote | sticky ------------------------------------------------------------------------------------------- 1 | 1 | Awesome Sauce | | 1369998600 | 1 | 2 | 1 | 0 As you can see I can only see the title. Where are the other field contents?", "Anthology for children; contains story about friendly Martian on postapocalyptic Earth I'm looking for the title of an anthology of children's science fiction stories from the 1950s. The best of the bunch involved a Martian who visited earth, and realized we'd blown ourselves up in a nuclear war and had fallen into savagery. The Martian is a vegetarian who subsists on biscuits made by a machine he brought with him, and communicates by using one of his tentacles to feed messages direction to/from the brain of the person he's talking to. Inadvertently left behind by his expedition, he initially befriended some children, and eventually managed to rebuild civilization. Presently he dies, but when another expedition comes a generation later, they find the civilization he rebuilt. there were other stories, but that was the best one. If I can't find the name of the book it was in, I'd be happy to settle for the name of the author and the title of the story.", "Cancelled UK visa on entry" ]

[ "Creating a DateTime in a specific Time Zone in c# I'm trying to create a unit test to test the case for when the timezone changes on a machine because it has been incorrectly set and then corrected. In the test I need to be able to create DateTime objects in a none local time zone to ensure that people running the test can do so successfully irrespective of where they are located. From what I can see from the DateTime constructor I can set the TimeZone to be either the local timezone, the UTC timezone or not specified. How do I create a DateTime with a specific timezone like PST?", "Is there a feasible way to take a one year break from a IT job and work as a crew member on a big ship? How can one go about this? I am a recreational sailor and know intermediate sailing, coastal navigation, radio handling and all that stuff. I think this could be the experience of a life time. Where should I look? I imagine getting it would be hard since obviously this is a lucrative job.", "Generalizing $\\,r(n^2) = r(n)^2,\\,$ for $\\,r(n) := $ reverse the digits of $n$ I'm assuming this theorem was found by someone else before, but I found this relationship between square numbers of 3 digits or less. The theorem is this: If you reverse the digits in a square number, then the result will also be a square number. Take the square 961. It is 31 squared, and if you reverse the digits you will get 169, which is also a square number. Plus, 31 and 13(the roots of these reversed squares) are also reverses of eachother. The problem is this breaks with 4 or more digits. If I take the square 1024 and reverse the digits, I get 4201, which is not a square. How can I expand this theorem to fit 4 or more digits?", "Prove $2^k+1$ divisible by 3 for odd K", "Word for someone who pays attention to details", "wp_delete_auto_drafts() deletes links in menus Since yesterday the wp_scheduled_auto_draft_delete cron job somehow deletes all page entries from our menus. All entries in the table wp_postmeta with meta_key = '_menu_item_object' and meta_value = 'page' get deleted in the process. By tracing back the DELETE query I found out that the menu entries are deleted by a function called _wp_delete_post_menu_item. I got the following stacktrace for that function: #0 _wp_delete_post_menu_item(3244) #1 call_user_func_array(_wp_delete_post_menu_item, Array ([0] =&gt; 3244)) called at [/srv/www/htdocs/biva/wp-includes/plugin.php:470] #2 do_action(delete_post, 3244) called at [/srv/www/htdocs/biva/wp-includes/post.php:2483] #3 wp_delete_post(3244, 1) called at [/srv/www/htdocs/biva/wp-includes/post.php:5645] #4 wp_delete_auto_drafts() #5 call_user_func_array(wp_delete_auto_drafts, Array ()) called at [/srv/www/htdocs/biva/wp-includes/plugin.php:546] #6 do_action_ref_array(wp_scheduled_auto_draft_delete, Array ()) called at [/srv/www/htdocs/biva/wp-cron.php:100] But I'm stuck here, I'm not a wordpress developer and I have no clue why deleting old drafts results in deleting attached menu entries although the main pages still exist. Workaround: As a workaround we added the following to the top of wp-config, wich will disable wp-cron: /** Disable wp-cron to prevent menu from getting deleted. Detailed Bug description: http://wordpress.stackexchange.com/questions/145953 **/ define('DISABLE_WP_CRON', true); If you are experiencing similar difficulties you might try locking the rows in the table wp_postmeta with meta_key = '_menu_item_object' and meta_value = 'page' and then tracing back the error message when WP trys to delete these rows, that's how we nailed down our error. Reproduce the Error: It is definitely the stealth publish plugin that is causing our error, one can easily reproduce it, by doing the following: Install a fresh Wordpress 3.9.1. Install the stealth publish plugin . Create a few test pages and add them to a new menu. Create a new page, with some dummy content, but do not save it!. Leave the page without saving. Change the system time 8 days into the future. The wp_scheduled_auto_draft_delete cron job will run because it runs daily and it hasn't run for 7 days as soon as you visit your page. It will then find your never saved dummy page delete it as it is older than 7 days and the menu will vanish. You might need to refresh the page a few times till the effect becomes visible. I've recorded a screencast on how to reproduce the error (but I took not the time to comment it):", "How to select lenses for outdoor sports photography? I would like to get into sports photography, and would probably want a better telephoto lens so I can get better close up shots. What other factors should I keep in mind as I make my choice? Does IS (or VR) matter? What is a good focal length? I'll probably be shooting mostly little league baseball/softball, church softball leagues, and kids soccer.", "Tracking very long shot with no points in common between first and last frame Is it possible to track an handheld shot (there is already an answer on here about tripod shots: ) that doesn't have any visible points in common between the first and the last frame? As an example, imagine a shot of someone driving in a car for thirty minutes. Obviously everything from the first couple of seconds won't be there anymore at minute 15.", "How to do a generalized linear model with multiple dependent variables in R? I have six dependent variables (count data) and several independent variables, I see that in a MMR the script goes like this: my.model &lt;- lm(cbind(DV1,DV2,DV3,DV4,DV5,DV6) ~ IV1 + IV2 + ... + IVn) But, since my data are counts, I want to use a generalized linear model and I tried this: my.model &lt;- glm(cbind(DV1,DV2,DV3,DV4,DV5,DV6) ~ IV1 + IV2 + ... + IVn, family=\"poisson\") And appears this error message: Error in glm.fit(x = c(1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, : (subscript) logical subscript too long` Can anyone explain me this error message or a way to solve my problem?", "Show that the $\\max{ \\{ x,y \\} }= \\frac{x+y+|x-y|}{2}$. Show that the $\\max{ \\{ x,y \\} }= \\dfrac{x+y+|x-y|}{2}$. I do not understand how to go about completing this problem or even where to start.", "I have a custom .desktop file: [Desktop Entry] Type=Application Terminal=false Icon[en_US]=/home/alex/bin/idea-IC-173.4127.27/bin/idea.png Name[en_US]=IntelliJ Exec=/home/alex/bin/idea-IC-173.4127.27/bin/idea.sh Name=IntelliJ Icon=/home/alex/bin/idea-IC-173.4127.27/bin/idea.png Output of ls -lha .local/share/applications/intellij.desktop: -rwx--x--x 1 alex alex 248 Dez 30 10:54 .local/share/applications/intellij.desktop Answers posted to a previous question () don't work for me. I can find this launcher in Activities and I can double click on that file and IntelliJ will start. Nevertheless, I cannot add this launcher as a favorite to the dock. The option does not show up.", "Importing installed package from script raises \"AttributeError: module has no attribute\" or \"ImportError: cannot import name\"", "How do I complete the square from the point I have left off at, and is this correct so far? I have a normal prior for $\\beta$ of the form $p(\\beta|\\sigma^2)\\sim \\mathcal{N}(0,\\sigma^2V)$, to get: $p(\\beta|\\sigma^2)=(2\\pi\\sigma^2V)^\\frac{p}{2}\\exp[-\\frac{1}{2\\sigma^2}\\beta^T\\beta]$ where $\\beta^T\\beta$ is $\\sum\\limits_{i=1}^p \\beta_i^2$. My likelihood has a normal distribtuion for the data points y of the form $p(y|\\beta,\\sigma^2)\\sim\\mathcal{N}(B\\beta,\\sigma^2I) $ $p(y|\\beta,\\sigma^2)=(2\\pi \\sigma^2V)^\\frac{n}{2}\\exp[-\\frac{1}{2\\sigma^2}({\\bf y}-{\\bf B}{\\bf \\beta})^T({\\bf y}-{\\bf B}{\\bf \\beta})]$ (Note that $\\beta$ is a matrix/vector too, \\bf does not work.) To get my posterior for $\\beta$ I combined the above, took the exponential parts only, and then expanded to get: $\\exp[-\\frac{1}{2\\sigma^2}({\\bf y}^T{\\bf y}-{\\bf y}^T{\\bf B}\\beta-\\beta{\\bf B}^T{\\bf y}-\\beta^T{\\bf B}^T{\\bf B}\\beta)]\\exp[-\\frac{1}{2\\sigma^2}({\\bf \\beta}^T{\\bf B})]$. I dropped the $({\\bf y}^T{\\bf y})$ term, as is not a function of $\\beta$. Putting into one expression without the exponential: $-\\frac{1}{2\\sigma^2}(-{\\bf y}^T{\\bf B}\\beta-\\beta{\\bf B}^T{\\bf y}-\\beta^T{\\bf B}^T{\\bf B}\\beta+{\\bf \\beta}^T{\\bf B})$. I know I need to combine the similar terms and get into the form of the multivariate normal distribution, which is what I am aiming for, but I am unsure how to do this? I probably have to add an extra term to the expression to get it into the correct form? Note: This is not homework, it's a project, but my Bayesian working knowledge is not good at all and so I need to understand the working out. I intend to integrate out the $\\beta$ and then the $\\sigma^2$ after getting into the multivariate form.", "Divisor in $\\mathbb{C}[X]$ $\\implies$ divisor in $\\mathbb{R}[X]$? let $P \\in \\mathbb{R}[X]$ be a real polynomial divisible by a polynomial $Q \\in \\mathbb{R}[X]$ in $\\mathbb{C}[X]$. How can I easily show that $P$ is also divisible by $Q$ in $\\mathbb{R}[X]$? A simple argument without using higher algebraic theorems is desirable. If I could use instruments of higher algebra, the exercise I have to do in whole would be done in two lines. But I'm not allowed to use. I think there would be an easy argument which I can't see yet because of my mental fogginess that I have sometimes. Thank you beforehand.", "Is the localization of a PID a PID? Let $A$ be a commutative ring and $S$ a multiplicative closed subset of $A$. If $A$ is a PID, show that $S^{-1}A$ is a PID. I've taken an ideal $I$ of $S^{-1}A$ and I've tried to see that is generated by one element; the ideal $I$ has the form $S^{-1}J$ with $J$ an ideal of $A$. $J$ is generated by one element but I can't see why $I$ has to be generated by one element, maybe I'm wrong.", "How can I disable cloud-init? I have a fully-configured instance and an image from that for an autoscaling group. When autoscaling new instances from this image, it calls cloud-init. cloud-init changes the hostname and breaks fstab. I want to prevent cloud-init from starting on instance launch.", "Global hotkey in console application", "Misleading chat usercard on SE 2.0 chat", "Hotspot and Internet access together — why not? If I try to set up a hotspot in GNOME, I get the following message: If you have a connection to the Internet other than wireless, you can use it to share your internet connection with others. Switching on the wireless hotspot will disconnect you from &lt;network name&gt;. It is not possible to access the internet through your wireless while the hotspot is active. What are the technical reasons why I can't set up an Hotspot and be connected to the Internet at the same time?", "This thought occurred to me earlier and I'm surprised I hadn't considered it previously. I get the feeling that no meaningful generalization can occur in a non-separable Banach space but on the surface it seems like a meaningful generalization can be had if the Banach space is separable. Even if it's possible, convergence and other issues likely severely complicate the matter." ]

[ "I was really happy when I heard that HoTD would be continued. And even happier when the first new chapter actually came. but now after several months of waiting there still has been no other chapter. So my question is, has HoTD gone on hiatus again ?", "Easy way to write contents of a Java InputStream to an OutputStream I was surprised to find today that I couldn't track down any simple way to write the contents of an InputStream to an OutputStream in Java. Obviously, the byte buffer code isn't difficult to write, but I suspect I'm just missing something which would make my life easier (and the code clearer). So, given an InputStream in and an OutputStream out, is there a simpler way to write the following? byte[] buffer = new byte[1024]; int len = in.read(buffer); while (len != -1) { out.write(buffer, 0, len); len = in.read(buffer); }", "Consider the following file: \\documentclass{beamer} \\setbeamercolor{title}{bg=red} \\setbeamercolor{author}{bg=yellow} \\setbeamercolor{date}{bg=} \\setbeamercolor{institute}{fg=red,bg=green} \\title{TitelTitelTitel} \\author{meiermueller} \\institute{Institute} \\date{lalala} \\begin{document} \\usebackgroundtemplate{\\color{blue}\\rule{20cm}{15cm}} \\begin{frame} \\titlepage \\end{frame} \\end{document} On one of my computers (using MiKTeX 2.9 and beamer 2015/01/05 3.36), the result is the following: Note how, in particular, the date box has a transparent background On my other computer, I installed a new MiKTeX version (2.9.6800), including beamer 2018/09/02 v3.52, and get this: Here, the date field has a white background, and I cannot seem to get it to be transparent. Apparently, the difference has some relation to the beamer version, or maybe some other change in the new MiKTeX version. But what ist the reason, and how do I get transparent backgrounds?", "What differentiates the scientific method from other methods From the controversy in , I would like to know what differentiates \"the scientific method\" from other method. I'm asking for differentiation, rather than a definition, because definitions call for an all encompassing answer, which is often hard to find. If someone asks \"what is an alternative to the scientific method,\" I would like to be able to start by being able to reliably say whether a particular method is the scientific method or not. Of course, being a linguistic issue, the definitions of words themselves are flexible. For instance, it is not uncommon to hear one in science talk of \"truth\" in a sense which is incompatable with the mathematical meaning of \"truth.\" Accordingly, I would like to stick to the following ideals in wording whenever possible: Prefer mathematically accurate terminology. Ideally the word \"proof\" should be used in the form found in proof theory, and \"true\" and \"false\" should be used in the form of Boolean algebra. No method should claim a hypothesis which predicts the state of the future is \"true\" unless they claim soothsaying abilities (most scientific theories include a random variable to avoid needing to claim soothsaying abilities... this is legitimate) Words which imply direction should be clarified carefully. \"Good\" and \"bad\" are notoriously difficult, but phrases such as \"advancing society\" can also be very tricky as well. The physical world and the world of information theory should be treated differently. In particular, the concept of \"testing a hypothesis\" will likely need to be broken down into testing and observing the physical world, taking measurements (which should have errors associated with them), and only then is the hypothesis compared against the results of the measurements. Mathematically extending arguments into infinity (such as claiming some specific cellular level learning process qualifies as the scientific method) are valid, but may rapidly make it harder to distinguish non-scientific methods from scientific ones. Such claims should be made carefully, but they are not inherently invalid. If these ideals are too strict, you may bend them, but you should qualify such choices with an explanation of why my recommended wording choices are too strict. Their goal is to put different methodologies on the levelest playing fields that I can manage in this medium. Being stack exchange, bonus points for references to existing theories, though you may need to paraphrase their results to fit with the ideals I'm recommending for these answers. Answers may be tested two ways: Positive: If we think something is the scientific method, does it meet the requirements set forth? Negative: If we think something is not the scientific method, does the answer explain why it is not?", "Possible Duplicate: If in a multiple linear regression (enter method) the general model isn't significant (F>.05) but one of the predictors is significant (β&lt;.05), should I consider it as a significant result?", "In WPF, what are the differences between the x:Name and Name attributes?", "Do creatures that enter the battlefield at the same time see each other enter?", "Find the limit of $\\lim\\limits_{(x,y)\\to (0,0)} \\frac{x^2y^2}{x^2y^2+(x-y)^2}$", "I'm about to fly from Istanbul to Seoul and I have a useful amount of Turkish Lira (TRY) left but I don't have any South Korean Won (KRW) to pay for the metro to my hostel when I get there. Several times in the past I've ended up being stuck with currencies that are very difficult to exchange in the country I've arrived in. Can I buy KRW at the airport in Istanbul? (I've also asked , since Stack Exchange questions are meant more for the long tail than just for the original asker.)", "Get in vs. get on Possible Duplicate: I'm an EFL (English as a foreign language) teacher and I haven't been able to come up with a good principle for which preposition to use after get when referring to transportation. Some examples: Get in: a car/taxi/van/truck, etc. Get on: a bus/plane/bike/truck, etc. How can one choose whether to use in or on? Note that in some cases, such as the example with truck, either preposition is possible but the choice affects the meaning. I've been telling my students that there is no rule, so they just have to memorize which preposition to use, but I'm really hoping I'm wrong. This question would be better suited for the upcoming Stack Exchange, but it hasn't entered beta yet. More .", "Plotting two variables as lines using ggplot2 on the same graph", "A gateway to a new world/future where things can be improved with use This book is about an explorer (with robot companion) who walks through a \"gateway\" into the future/parallel world. In this world, things that are created do not fall into disrepair, instead things get better. The main character is kidnapped early on in the story and forced to labor by beating the outside of a castle with a spear. It is explained to him that this makes the wall better and able to resist attacks by these weapons. In his cell, he meets a man wearing an extravagant shirt and asks about it and the man explains to him that the shirt has been in his family for several generations, which is why it looks so nice. To escape from the jail cell, the man tears one of his zippers from his jump suit and uses it like a saw to cut a hole in the wall. He escapes with the man in the fancy shirt and a woman. The woman, is something special in this world. (She can focus on the change that is happening to an item and somehow enhance or speed up the process) The man makes a wheeled cart for them to escape in. While the wheels are at first rough and wobbly, they soon \"become better\" and spin better.", "I’m looking for an adjective/ noun that describes a person who loves life, traveling, great food, always doing things which gets adrenaline kicking and is a always ready for attempting things for pleasure only", "OpenLayers Plugin Error: latitude or longitude exceeded limits I'm aware the 'traceback' OpenLayers plugin error has been dealt with before, so apologies for raising the issue once again. Unfortunately for me, the solutions posted were way over my head, e.g. using workarounds and code posted on github, etc. I find it all mind-boggling. If anyone could post a step by step answer for an absolute beginner like me I would be eternally grateful! Thank you. I hope that one day I can contribute something. The error message reads: An error has occured while executing Python code: Traceback (most recent call last): File \"C:/Users/MCMA1580/.qgis//python/plugins\\openlayers_plugin\\openlayers_plugin.py\", line 48, in addLayer self.__plugin.addLayer(self) File \"C:/Users/MCMA1580/.qgis//python/plugins\\openlayers_plugin\\openlayers_plugin.py\", line 190, in addLayer self.__setMapSrsGoogle() File \"C:/Users/MCMA1580/.qgis//python/plugins\\openlayers_plugin\\openlayers_plugin.py\", line 249, in __setMapSrsGoogle extMap = coodTrans.transform(extMap, QgsCoordinateTransform.ForwardTransform) QgsCsException: forward transform of (0.884883, 2.549197) PROJ.4: +proj=longlat +datum=WGS84 +no_defs +to +proj=merc +a=6378137 +b=6378137 +lat_ts=0.0 +lon_0=0.0 +x_0=0.0 +y_0=0 +k=1.0 +units=m +nadgrids=@null +wktext +no_defs Error: latitude or longitude exceeded limits", "I'd really like your help proving: $(A\\rightarrow B),(A\\rightarrow C)\\rightarrow B, \\mapsto_{HPC} B $ Where $HPC$ is the Hilbert's system proof which contains the following relevant axioms: $A\\rightarrow(B \\rightarrow A)$ $(A\\rightarrow(B\\rightarrow C)) \\to ((A\\rightarrow B)\\rightarrow(A\\rightarrow C))$ $(A\\rightarrow B)\\rightarrow ((A\\rightarrow\\bar{B})\\rightarrow \\bar{A})$ $\\bar{\\bar{A}} \\rightarrow A$ In addition tried to use these following lemmas: $\\bar{A} \\rightarrow (A \\rightarrow C) $ and $(A\\rightarrow B)\\rightarrow (\\bar{B} \\rightarrow \\bar{A})$. Any suggestions?", "Altium: How can I edit a component from a library", "Consider two different shaped containers having same area: one is cylinder, the other is like an inverted pyramid (roughly). Both have the same level of water, the weight of the inverted pyramidal container will therefore be greater than that of the cylinder. But I know from Pascal's law that the pressure should be same in both containers. If the base areas are the same then the force (weight as measured by a scale) should also be the same. Why are the weights different?", "What is the black thing on the circuit What is the black thing on the below circuit? Is it used to hide the IC (or other components) that is used on the circuit? What material is it?", "How can I get Google Sheets to treat my form-submitted strings as plain text and preserve leading zeros? I have Google Forms where users enter information, some of which contains leading zeros (e.g. zip codes, ID numbers). However, when this data is saved to the Google Sheet, it doesn't treat it as plain text and strips the zero. The form fields are text fields with no validation. I have tried to format the range of cells containing these values as plain text, but it seems Sheets does not set the formatting as plain text unless there is already text in a cell. So I can format a column as plain text, submit the form, and the leading zero will still be stripped. I tried writing an apps script to deal with this but there's no good way for me to deploy it to the users who would need it. How can I get around this without having to instruct users to prepend a single quote to their form entry? This is such a small thing, but I can't find a good simple solution to what it seems must be a common problem. If I can't get this to work I may have to drop Google Forms/Sheets altogether.", "I'm looking for a movie I've seen as a kid, the details are foggy and sparse but I'll try my best following : What is it?: An animated movie. Tell us what it isn't: It is not . Tell us what made it memorable: A planet where some brain-sucking insect-like aliens live, also an old bald man lives on the same planet. When did you see this film?: Late 80's, early 90's. How old was it?: If I've seen the movie on TV in Spain, is a pretty safe bet that it will be at least 5 years old. Was it part of a series?: I don't think so. Plot: No clue, sorry. What language was it in?: The movie was dubbed to Spanish (Spain). No detail is too insignificant What details can I recall?: Sci-Fi story with one character being an old bald man living on a planet where some insect-ish aliens can open your skull and suck your brain. Habitat of those insect-ish foes was depicted in light blue colors, I kinda remember giant mushrooms as well. A young boy befriends the old baldie, the boy came to the planet with some adults. Other details I'm not completely sure (maybe my mind is filling the gaps): I think that the movie was drawn using , not 100% sure though. I cannot remember which year I've seen the movie, but it should be late 80's or early 90's. I'm pretty sure that I've seen the movie in Spanish TV (not rented videotape). Somehow the young boy was the young version of the old baldie (time travel?). The old man lives in a wood house near the brain-sucking insect habitat, as many old man does he spend his time on the porch. Try to offer unique details As anyone would expect from this kind of movie, there's a scene where the alien insects attack a group of people trying to suck their brains. A young boy was with those adults and survived with injuries in his head. The old bald man have some surgery in his head due to an attack he suffered years before." ]

[ "jQuery autocomplete tagging plug-in like StackOverflow's input tags? What solutions accomplish the same auto-completion that SO uses for entering tags? There are plugins that can handle one word but I haven't seen any that handle multiple words.", "I am looking for a good source on group theory aimed at physicists. I'd prefer one with a good general introduction to group theory, not just focusing on Lie groups or crystal groups but one that covers \"all\" the basics, and then, in addition, talks about the specific subjects of group theory relevant to physicists, i.e. also some stuff on representations etc. Is Wigner's text a good way to start? I guess it's a \"classic\", but I fear that its notation might be a bit outdated?", "How can I safely move a module to another folder? I created a module through Drupal Console, unfortunately it wasn't placed in a folder of its own, rather straight into /modules/custom. Before I noticed where it had gone, I enabled the module. In Drupal 6/7, this was easy to fix - I could literally just put the files into the correct path, clear the cache (maybe rebuild the registry, it wasn't an exact science), and all was well. The same isn't true for Drupal 8; I moved the files into a subfolder, rebuilt cache, and all requests tell me that Drupal is failing to include a required file. The particular file is a block class, and the path Drupal is trying to find it is where it used to be, not where I've moved it to. The bit of code objecting is in Symfony's ApcClassLoader, so I guess I need to clear something that's slightly above Drupal's head to get this path reference updated. How can I do that? Uninstalling and re-installing the module does work, but once there's important data stored that's not going to be an option. I was wrong, uninstalling and re-installing is not a viable option. After uninstalling and reinstalling, Drupal can no longer pick up the custom blocks the module defines. I'm guessing that reference is cached somewhere that isn't cleared when the module is uninstalled. Just need to find out where that is and how to clear it...", "Datasets constructed for a purpose similar to that of Anscombe's quartet I've just come across (four datasets that have almost indistinguishable descriptive statistics but look very different when plotted) and I am curious if there are other more or less well-known datasets that have been created to demonstrate the importance of certain aspects of statistical analyses.", "Why is there an electric field in a wire even though it is a conductor? If you take a perfect conductor, there cannot be a field across it since if there were, the particles would arrange themselves in a way to cancel out the field right? Yet, why does the same not hold true for a wire. A wire is essentially a long, thin conductor yet electrons do indeed flow so there must be an electric field. Does this not contradict with what happens in a conductor? Why don't the electrons re-arrange to cancel out the electric field?", "How do I split a forest tree into two trees with proper vertical alignment? \\documentclass[oneside,12pt]{article} \\usepackage{geometry} \\usepackage{microtype} \\usepackage[utf8]{inputenc} \\usepackage[T1]{fontenc} \\usepackage{lmodern} \\usepackage{enumitem} \\setlist[enumerate,1]{label=\\bfseries\\Alph*,align=left,leftmargin=*, labelsep=1.5em} \\setlist[enumerate,2]{label=\\arabic*.,labelindent=1em,labelsep=1.5em, leftmargin=*} \\usepackage{amssymb} \\usepackage{amsmath} \\usepackage{amsthm} \\theoremstyle{definition} \\newtheorem*{sol}{Solution} \\usepackage{forest} \\forestset{ ass/.append style={ before computing xy={l=\\baselineskip}, no edge }, prooftree/.style={ for tree={ child anchor=north, parent anchor=south } } } \\begin{document} \\subsection*{Exercises 29} \\begin{enumerate} \\item Use QL trees to evaluate the entailment claims (1) to (10) in Exercises 28A. \\begin{enumerate} \\item $\\forall x(Fx\\supset Gx)\\vDash\\forall x(Gx\\supset Fx)$ \\begin{forest} prooftree [$\\forall x(Fx\\supset Gx)$ [$\\neg\\forall x(Gx\\supset Fx)\\checkmark$,ass [$\\exists x\\neg(Gx\\supset Fx)\\checkmark$,ass [$\\neg(Ga\\supset Fa)\\checkmark$,ass [$Ga$,ass [$\\neg Fa$,ass [$(Fa\\supset Ga)\\checkmark$,ass [$\\neg Fa$] [$Ga$]]]]]]]] \\end{forest} $\\neg Fa$ and $Ga$ make the premisses and the negation of conclusion true. Thus, the entailment is invalid. \\item $\\forall x(Fx\\supset Gx)\\vDash\\forall x(\\neg Gx\\supset\\neg Fx)$ \\begin{forest} prooftree [$\\forall x(Fx\\supset Gx)$ [$\\neg\\forall x(\\neg Gx\\supset\\neg Fx)\\checkmark$,ass [$\\exists x\\neg(\\neg Gx\\supset\\neg Fx)\\checkmark$,ass [$\\neg(\\neg Ga\\supset\\neg Fa)\\checkmark$,ass [$\\neg Ga$,ass [$\\neg\\neg Fa$,ass [$(Fa\\supset Ga)\\checkmark$,ass [$\\neg Fa$ [*,ass]] [$Ga$ [*,ass]]]]]]]]] \\end{forest} Since the tree closes, the entailment is valid. \\item $\\forall x\\exists yLxy\\vDash\\forall y\\exists xLyx$ \\begin{forest} prooftree [$\\forall x\\exists yLxy$ [$\\neg\\forall y\\exists xLyx\\checkmark$,ass [$\\exists y\\neg\\exists xLyx\\checkmark$,ass [$\\neg\\exists xLax\\checkmark$,ass [$\\forall x\\neg Lax$,ass [$\\exists yLay\\checkmark$,ass [$Lab$,ass]]]]]]] \\end{forest} \\begin{forest} prooftree [$\\neg Lab$,ass [*,ass]] \\end{forest} \\item $\\forall x((Fx\\wedge Gx)\\supset Hx)\\vDash\\forall x(Fx\\supset(Gx\\supset Hx))$ \\item $(\\forall xFx\\vee\\forall xGx)\\vDash\\forall(Fx\\vee Gx)$ \\item $\\forall x(Fx\\supset Gx),\\forall x(\\neg Gx\\supset Hx)\\vDash \\forall x(Fx\\supset\\neg Hx)$ \\item $\\exists x(Fx\\wedge Gx),\\forall x(\\neg Hx\\supset\\neg Gx)\\vDash \\exists x(Fx\\wedge Hx)$ \\item $\\forall x\\exists y(Fy\\supset Gx)\\vDash\\forall y\\exists x(Gx\\supset Fy)$ \\item $\\forall x\\forall y(Lxy\\supset Lyx)\\vDash\\forall xLxx$ \\item $\\forall x(\\exists yLxy\\supset\\forall zLzx)\\vDash\\forall x\\forall y (Lxy\\supset Lyx)$ \\end{enumerate} \\end{enumerate} \\end{document} Usually, I have to manually split a forest tree into two to emulate page breaking in a forest tree. However, the second tree doesn't vertically align with the first as in the picture below. How can I vertically align them together? @cfr", "Can a multiclass sorcerer make spell slots for their other class using sorcery points? For example: can a multiclassed sorcerer 3 / warlock 1 use Flexible Casting to create a warlock spell slot?", "Is there a way to force Google Photos to recognize new faces? I have \"Face grouping\" enabled in my Google account and I can see around 10 faces successfully tagged when I go to my Albums. However, there's a lot of other people who are not tagged, as well as some unrecognized photos of people who are already tagged. Is there a way to force Google Photos to run the facial recognition algorithm on a given photo, so that it adds new faces or maps a new photo to an existing face?", "Is there a way to recover files from a storage device partially overwritten with dd? I'm an idiot, I was writing an image to a USB drive using dd when instead of typing /dev/sdb I typed /dev/sdd and wrote the 135mb image to my 750gb External Hardrive full of files. Is there ANY possibility of recovering the files or did dd completely zero out the drive? Please help, as this is one of the lowest points of my life EVER. dd finished writing the 135mb image in 5 seconds, so I didn't have a chance to stop it. By the time I knew what happened to was too late. The command was as follows: sudo dd if=generic.img of=/dev/sdd bs=1M EDIT2: The External Harddrive's filesystem was FAT32(I've had the drive for awhile and FAT32 was the most Universal FS at the time). I also have a 2TB drive I just got which I was planning on moving most of the files to from the 750gb, If needed I can use it to transfer the Recovered files to.", "how to count dates entries monthwise from a resultset", "Dual boot UEFI Windows 7 and Ubuntu 12.04 (both 64 bits). W7 entry doesn't appear in GRUB", "How do I play a YouTube video in the background on my iPad?", "How to escape ampersand in \\acro command? I am trying to use the acronym package to create an acronym list. The problem is that one of the acronyms I need to use contains an ampersand ('&amp;'). But when I try to compile the .tex file I get this error: ! Missing \\endcsname inserted. &lt;to be read again&gt; \\&amp; l.2 ...&amp;M}[\\AC@hyperlink{M\\&amp;M}{M\\&amp;M}]{I like them} Here is an example: \\usepackage{amsmath} \\usepackage{acronym} \\begin{document} \\begin{acronym} \\acro{M\\&amp;M}{I like them} \\end{acronym} \\end{document} So how do I use an ampersand in an acronym using the acronym package? More generally, how is it possible to apply special formatting to a single acronym? For example \\acro{\\textit{IAF}}{Italic acronym frenzy}", "Many To Many Relationships", "I have a few satellites and stations orbiting my planets, but I'd like to add onto them. I've seen numerous videos on using docking clamps to attach my new ship to the existing station, but can I do that on a part-by-part basis? For example, I take an extra fuel tank up there, can I attach just the tank to my station, then send my vessel back to Kerbin? I'm not talking about refueling, but rather transferring individual parts from my ship to the station in orbit. I'd prefer to not have to use an unmanned probe and jettison everything but the desired part in space after docking if possible, but if that's the only way I guess I don't have a choice.", "Here is the situation. I have hexagonal board,and a unit on it,with speed or move value 4.Diffrent terrain has a diffrent cost.When i click on the unit,game should show me a move range. My solution was to check each hex in range of 4,with A* pathfinding,and if path cost was less than 4 then this hex was in range.Finally game nicely show me range of that unit. My question is: Is there other solution to search for range on hex grids or square grid,because even if i am really proud of what i did in my solution,i think,it is a little to exaggerated?:)) What make me ask this question?I noticed that when unit speed is 4 or 6 or even 8,time to computing range for my computer was really good,but when speed was 10 and more i noticed that i needed to wait few second to compute.Well in real games i rather dont see something like this and my A* pathfinding is rather well optimized,so im thinking that my solution is wrong. Thanks for any replies.", "I add js file with drupal_add_js in hook_form_alter, it is ok and I see it in list of js loaded in page, but when I submit form and form not validate and return to that form (after validation failed) I don't see js files that added to form, why this happened? and how can add my js file in that form after validation failed ? some part of my code function mymodle_form_alter(&amp;$form, $form_state, $form_id) { if ($form_id == 'news_node_form') { drupal_add_js(drupal_get_path('module', 'mymodule') . '/js/mymodulejsfile.js'); //, array('scope' =&gt; 'footer','weight' =&gt; 10)); } } code work correctly in add and edit form, but when form submit and validation failed it show validation error but my js file not loaded in page (I checked html source and check firebug script files), but there is not my js file,", "How do I format a number in Java?", "Normal Subgroup Counterexample Im having trouble with the second part of this question, Let $H$ be a normal subgroup of $G$ with $|G:H| = n$, i) Prove $g^n \\in H$ $\\forall g \\in G$ (which i have done) ii) Give an example to show that this all false when $H$ is not normal in $G$.(which I am having trouble with showing) Any suggestions?", "While reading a question here whose answer was Stephen Baxter's &quot;Light of Other Days&quot; book, it reminded me of a short story I read with a similar idea. Probably read at least 30-40 years ago, in English. The fact that the Government has invented a device that can view the past is made public (by a whistleblower, I believe). Historians go nuts besieging the government to look at their favorite time periods to reveal the truth about various historical &quot;facts&quot; and or &quot;mysteries&quot; (Who shot JFK? Who was Jack the Ripper? Was Helen of Troy really that beautiful? Did Jesus exist? etc, etc.) And the government is stonewalls most of them and claims it's expensive to operate, hard to control to get exact time/location, etc. So someone (maybe the whistleblower?), knowing it's possible, does math/construction and builds his own version, and realizes it's easy to make, cheap to operate, and easy to use. So he makes plans to stick it to the government by releasing the info. Maybe he tries to force the government to release the info, or they realize he has made it, so they grab him and try to convince him to stop. But he is not convinced until they tell him, it can't see back very far (maybe just a few days/weeks, because it needs exponentially more power the further you look back.) Finally the agents tell him: &quot;Don't you see, you can use it to see what's happening just a few minutes ago, or even now. Your company can't make widgets? Zoom in on your competitors and see how they make them. Think your wife is fooling around on you? Zoom in on her and track her to see if she is. Your pretty neighbor is taking a bath now? Zoom in and watch her... These devices mean no one will have any privacy now.&quot; At which point he tells them it's already too late. They kept him there so long that the letters he mailed will already be delivered to various newspapers, scientists, historians, etc." ]

[ "Should we use 'Title Case' or 'Sentence case' for headlines and buttons? I am wondering if we should use or for buttons and headings in websites and web/mobile apps? Title Case: Manage my Account Delete my Account Sentence case: Manage my account Delete my account In I found the recommendation 'choose your style and be consistent'. This is it? Aren't there any other (additional) recommendations or sources. Like for specific use cases or apps where the one style would be preferred over the other? Edit: The question refers primarily to English, but differences in other languages are also good to know.", "When I try to play multiplayer I type in the only server I know, which the game says was right, then click Play and it loads. Then it says Can't connect to server: bad log in. How can I fix this?", "it VS. this Vs. that", "How to remove \"onclick\" with JQuery?", "Which function (s) is(are) the k-th derivative of itself? As I attempted to solve for a function that is the $k$-th derivative of itself where $k$ is some natural number, and generalise the result, I realised it gets very hard to prove anything. For $k= 1$, apart from trivial corner cases, it's the exponential function with any constant multiplied. For $k=2$, along with the exponential function and it's reciprocal, it works for their sum along with any mixture by constants multiplied... For any $k$, I guessed it should be of the form $e^{x w}$ where w is the $k$-th root of unity. And we can add all these $k$ terms for each root with constants multiplied. While it is easy to verify it's satisfying the condition, it is beyond my scope to prove this is the only family of functions that satisfy it. I am hoping for some interesting math at work here, and want to know if this is an already established fact. Also, how do I prove anything here?", "Story about a sentient star system, in a 50s or early 60s anthology Story about a sentient star system, possibly in f&amp;sf anthology from 50s or early 60s. I know this is a long shot, but I hope someone will know of this story. I believe it was called \"Darkness or into the darkness\". End of the story had it spinning off a galaxy, (possibly ours?).", "Prove $\\frac{|a+b|}{1+|a+b|}<\\frac{|a|}{1+|a|}+\\frac{|b|}{1+|b|}$. Prove that for every $a, b\\in R\\setminus\\{0\\}$ is correct this inequality: $$\\frac{|a+b|}{1+|a+b|}&lt;\\frac{|a|}{1+|a|}+\\frac{|b|}{1+|b|}.$$", "How to configure axis on pgfplots? How to configure axis on pgfplots? Similar for this. \\documentclass{article} \\usepackage{tikz,pgfplots} \\pagestyle{empty} \\begin{document} \\begin{tikzpicture}[&gt;=latex] %x axis \\draw[-&gt;] (-5,0) -- (5,0) node[below] {$x$}; \\foreach \\x in {-4,...,-1,1,2,...,4} \\draw[shift={(\\x,0)}] (0pt,2pt) -- (0pt,-2pt) node[below] {\\footnotesize $\\x$}; %y axis \\draw[-&gt;] (0,-5) -- (0,5) node[left] {$y$}; \\foreach \\y in {-4,...,-1,1,2,...,4} \\draw[shift={(0,\\y)}] (2pt,0pt) -- (-2pt,0pt) node[left] {\\footnotesize $\\y$}; \\node[below left] at (0,0) {\\footnotesize $0$}; \\end{tikzpicture} \\end{document}", "I am confused with the grammar here. Which is grammatically correct? At which time will you call me? At what time will you call me? And why?", "How to add numbering to reference list but still use authoryear in natbib Is there an easy way to add numbers to the reference list generated by \\usepackage[authoryear]{natbib} with whatever style file (using plainnat for ease)? Specifically, I use \\cite and \\citenum from natbib in order to have some references show up in the text as author-year and others just appear as numbers. Switching authoryear out for numbers in the natbib options generates a reference list with numbered references, but also causes the references in the text to all appear as numbers, which I don't want. \\documentclass[12pt]{article} % use larger type; default would be 10pt \\usepackage[authoryear]{natbib} \\begin{document} \\cite{A} said this, but other research \\citenum{B,C} says otherwise. \\bibliographystyle{plainnat} \\bibliography{MalariaBib,MST} \\end{document}", "An element of a group has the same order as its inverse If $a$ is a group element, prove that $a$ and $a^{-1}$ have the same order. I tried doing this by contradiction. Assume $|a|\\neq|a^{-1}|$ Let $a^n=e$ for some $n\\in \\mathbb{Z}$ and $(a^{-1})^m=e$ for some $m\\in \\mathbb{Z}$, and we can assume that $m &lt; n$. Then $e= e*e = (a^n)((a^{-1})^m) = a^{n-m}$. However, $a^{n-m}=e$ implies that $n$ is not the order of $a$, which is a contradiction and $n=m$. But I realized this doesn't satisfy the condition if $a$ has infinite order. How do I prove that piece?", "Modern ice-age/plans for weapon hidden in genome", "How do you convert a byte array to a hexadecimal string, and vice versa?", "My has failed me. In Python, are the following two tests for equality equivalent? n = 5 # Test one. if n == 5: print 'Yay!' # Test two. if n is 5: print 'Yay!' Does this hold true for objects where you would be comparing instances (a list say)? Okay, so this kind of answers my question: L = [] L.append(1) if L == [1]: print 'Yay!' # Holds true, but... if L is [1]: print 'Yay!' # Doesn't. So == tests value where is tests to see if they are the same object?", "How do I find a point a given distance from another point along a line?", "Recently my paper is reviewed (by a professor from independent third party) and accepted by a journal. But, my employer allows me to publish this paper only without its name there. Publishing house is expecting affiliation for each author, i.e. I can not leave affiliation as blank. What should I write as the affiliation?", "Approximation of measurable function by simple functions", "Install Nvidia driver instead of nouveau I've installed Ubuntu 14.04 and I'm experiencing a fuzzy/blurry screen and bad support for multiple screens. I realized that Ubuntu installs nouveau as default, but I need to install nvidia drivers, so I tried this: sudo apt-add-repository ppa:ubuntu-x-swat/x-updates apt-get update apt-get install nvidia-current apt-get upgrade Now that nvidia is installed, you need to blacklist the nouveau driver so it don’t pop out when you will reboot. Create or edit the following file: nano /etc/modprobe.d/blacklist-nouveau.conf …and add these lines at the end: blacklist nouveau blacklist lbm-nouveau options nouveau modeset=0 alias nouveau off alias lbm-nouveau off I checked via the software &amp; updates if nvidia driver got installed successfully, and it says the driver installed is nvidia 304.117 I then tried to run: lshw -c video | grep 'configuration' and the result is that the driver is still nouveau: configuration: driver=nouveau latency=0 So how do I install and use the nvidia drivers?", "Find a recurrence relation for the number of ternary strings of length n that do not contain two consecutive 0s or two consecutive 1s.", "Traces of all positive powers of a matrix are zero implies it is nilpotent Let $A$ be an $n\\times n$ complex nilpotent matrix. Then we know that because all eigenvalues of $A$ must be $0$, it follows that $\\text{tr}(A^n)=0$ for all positive integers $n$. What I would like to show is the converse, that is, if $\\text{tr}(A^n)=0$ for all positive integers $n$, then $A$ is nilpotent. I tried to show that $0$ must be an eigenvalue of $A$, then try to show that all other eigenvalues must be equal to 0. However, I am stuck at the point where I need to show that $\\det(A)=0$. May I know of the approach to show that $A$ is nilpotent?" ]

[ "I came across this example when trying to mount a usb device inside a openvz container and I have never seen the construct in the second line before. Can you explain what it signifies? #!/bin/bash . /etc/vz/vz.conf", "How do I diff two text files in Windows Powershell? I have two text files and want to find the differences between them using Windows Powershell. Is there something similar to the Unix diff tool available? Or is there another other way I haven't considered? I've tried compare-object, but get this cryptic output: PS C:\\&gt; compare-object one.txt two.txt InputObject SideIndicator ----------- ------------- two.txt =&gt; one.txt &lt;=", "How to move Applications from phone to SD Card?", "How to enable the Edit button in Shutter? I am trying to enable the Edit button in Shutter. I installed the application from Ubuntu Software and are using Ubuntu 18.04. After taking a screenshot the Edit button is disabled. And when hovering the mouse pointer over the button the text \"Goo::Canvas/libgoo-canvas-perl needs to be installed for this feature\" is shown. I have tried to install the package libgoocanvas2-perl and restarted the computer, but the edit button is still not enabled: sudo apt install libgoocanvas2-perl That is the only package I can find. Anyone that knows how to fix this?", "How to fix gaps between flooring planks in mid-1800s house? I live in a mid-1800s house, which I plan to sell this Spring. The original (I think) wood flooring has gaps between the planks, some pretty sizable (photos follow). Is there any good fix for this? I've seen people use wood filler/epoxy, and it didn't seem to turn out well. Perhaps doing that and painting/dying it black might work better. I've heard the \"old\" solution was to pack those spaces with rope, but I don't think that would look better than the status quo. Any suggestions? Photos, big gap: Medium gap: Small gap:", "In Python, you can do this: import webbrowser webbrowser.open_new(\"http://example.com/\") It will open the passed in url in the default browser Is there a ruby equivalent?", "Why doesn't current pass through a resistance if there is another path without resistance? Why doesn't current pass through a resistance if there is another path without resistance? How does it know there is resistance on that path? Some clarification: I understand that some current will flow through the resistance. A depiction of this phenomenon through Ohm's laws does not answer the 'why' part of the question as it does not illuminate the process behind this phenomenon. There seems to be disagreement among the answers on whether the charge repulsions are enough to cause this effect. Cited research would be appreciated to resolve this issue. To refine what I mean by this question, I think I should give an example of why I am curious as to the causal background of this phenomenon. If charge repulsions do in fact repel 'current' in the example of the short circuit, then why does the same phenomenon not happen in other parallel circuits. (Again, I know that not all circuits behave ideally) I believe the question is expressed in the most straightforward way possible. This should, however, not affect the scope of the answers. I do not wish to see or think on the level of an electron as circuit behavior always includes a cumulative effect due to the nature of electrostatic interactions.", "multiple definition error including c++ header file with inline code from multiple sources I have a c++ header file containing a class. I want to use this class in several projects, bu I don't want to create a separate library for it, so I'm putting both methods declarations and definitions in the header file: // example.h #ifndef EXAMPLE_H_ #define EXAMPLE_H_ namespace test_ns{ class TestClass{ public: void testMethod(); }; void TestClass::testMethod(){ // some code here... } } // end namespace test_ns #endif If inside the same project I include this header from more than one cpp file, I get an error saying \"multiple definition of test_ns::TestClass::testMethod()\", while if I put the method definition inside the class body this does not happen: // example.h #ifndef EXAMPLE_H_ #define EXAMPLE_H_ namespace test_ns{ class TestClass{ public: void testMethod(){ // some code here... } }; } // end namespace test_ns #endif Since the class is defined inside a namespace, shouldn't the two forms be equivalent? Why is the method considered to be defined twice in the first case?", "Do I need internet/3G to use GPS? I have a Samsung Galaxy S2 that has some problems with the GPS: If I use internet my navigation works but when I turn the 3G off, GPS does not work. Do I need internet/3G to use GPS?", "Newton's cradle Why, when one releases 2 balls in , two balls on the opposite side bounce out at approximately the same speed as the 1st pair, rather than one ball at higher speed, or 3 balls at lower speed?", "I've searched the net for such information and found different command lines, like these ones: sudo apt-get remove application sudo apt-get remove application* sudo apt-get remove --purge application sudo apt-get remove --purge application* sudo apt-get purge application sudo apt-get purge application* So, what is the correct way? Is it necessary to use that \"*\"? After that, I also found these commands: sudo updatedb sudo locate application sudo rm -rf (file/folder name)", "Link to the recommended job is broken in the mobile apps", "How to handle OutOfMemoryError in Java?", "What is the difference between \"citizen\" and \"denizen\" Citizen: 1. A legally recognized subject ornational of a state or commonwealth, either native or naturalized. 2. An inhabitant of a particular town or city. Denizen: 1. An inhabitant or occupant of a particular place. Same thing?", "Prove $0! = 1$ from first principles", "Remove ajax call from regular links with jQuery Mobile", "How can I run ssh-add automatically, without a password prompt? I want to communicate between several computers on my network (static Ethernet), through SSH. In order to do that I need to run ssh-add every time I log in on a specific machine, how can I do it so that it's set up once and it doesn't ask me for the passphrase every time I log in or reboot my machine? I know that there is a way that you should add some lines to the bash_profile file, but I still need to type the password every time I reboot/log in to a specific machine. if [ -z \"$SSH_AUTH_SOCK\" ] ; then eval `ssh-agent -s` ssh-add fi", "Drawing a square root spiral", "Complicated FOR loop nesting. Having trouble cleaning up legacy code", "I have Ubuntu server 12.04 installed, so I have no GUI. When I do the command ifconfig, I cannot find my internal IP address. It says inet addr: 127.0.0.1. Here is the output of ifconfig -a: eth0 link encap:Ethernet HWaddr 00:06:4f:4a:66:f0 BROADCAST MULTICAST MTU:1500 Metric:1 RX packets:0 errors:0 dropped:0 overruns:0 frame:0 TX packets:0 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:0 (0.0 B) TX bytes:0 (0.0 B) eth1 link encap:Ethernet HWaddr 00:16:ec:05:c8:9c BROADCAST MULTICAST MTU:1500 Metric:1 RX packets:0 errors:0 dropped:0 overruns:0 frame:0 TX packets:0 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:0 (0.0 B) TX bytes:0 (0.0 B) lo Link encap:Local Loopback inet addr 127.0.0.1 Mask:255.0.0.0 inet6 addr: ::1/128 Scope:Host UP LOOPBACK RUNNING MTU:65536 Metric:1 RX packets:1800 errors:0 dropped:0 overruns:0 frame:0 Tx packets:1800 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:143896 (143.b KB) TX bytes:143896 (143.8 KB) here are the contents of etc/network/interfaces: # The loopback network interface auto lo iface lo inet loopback # The primary network interface auto eth0 iface eth0 inet dhcp If someone could edit this for me, the contents of etc/network/interfaces should be on separate lines. The output of host askubuntu.com was: ;; connection timed out; no servers could be reached. I set up owncloud and webmin a few months ago and was using them for a month with no problems. I think the power went off one day 2 months ago and I never turned the server back on until yesterday. I haven't done anything that would have affected the internet setup So i'm not sure why it doesn't work anymore. As far as my network topology goes, I have a pci-e network card for the pc. The ethernet line goes from the network card to a switch, and then to a modem/router from there." ]

[ "I know that each new tab on Google Chrome have its own process, but I have 14 chrome.exe processes running actually as I can see it on the Task Manager, and only two tabs are opened on Google Chrome. Could it be due to Chrome extensions? What other reason can open more chrome.exe process and how to avoid it?", "Why is the Descriptor not getting called when defined as instance attribute?", "Floating Objects and Weight The Situation: A ball is placed in a beaker filled with water and floats. It is also attached to the bottom of the beaker via a string. The Question: The ball is attached to the beaker, thus making the ball and beaker (and string included) a system. However, it is floating. Does the ball add to the weight of the beaker?", "How could I go about detecting (returning true/false) whether an ArrayList contains more than one of the same element in Java? Many thanks, Terry Edit Forgot to mention that I am not looking to compare \"Blocks\" with each other but their integer values. Each \"block\" has an int and this is what makes them different. I find the int of a particular Block by calling a method named \"getNum\" (e.g. table1[0][2].getNum();", "Picking a lock typically requires a DC 15 Dexterity check (Basic rules, p. 49). Likewise for manacles (p. 50), which can alternately be escaped with a DC 20 Dexterity check or broken with a DC 20 Strength check. But what happens if you fail? The general rules for ability checks state (p. 58): If the total equals or exceeds the DC, the ability check is a success—the creature overcomes the challenge at hand. Otherwise, it’s a failure, which means the character or monster makes no progress toward the objective or makes progress combined with a setback determined by the DM. As a DM, how can I handle this in practice? In our last session, the players wanted to get inside a locked building to rescue people trapped inside. Picking the lock seemed like an easy enough task for the rogue, but unluckily he failed the check, and I wasn’t prepared for the consequences. There wasn’t much time pressure and no obvious reason why he couldn’t try again, so I allowed another attempt, but it just didn’t feel right. I’m sure that similar situations will come up again, so I’d like some advice on how to deal with checks so that they don’t just turn into a tedious exercise of rolling until you succeed. I presume that was left out of the game for good reason, but I’m not sure what to do instead. I suspect that this was a good occasion to use “progress with a setback” but that’s a fairly new thing for D&amp;D and I’m not sure how to go about it. I’m unsure when I should use setbacks versus lack of progress, and in the latter case I’m unsure when I should allow players to try again versus requiring a different approach. For example, suppose that a manacled player tries to pick the lock and fails the DC 15 Dexterity check. Now, the player could try to pick it again, or he could try one of the other escape methods, or he could wait for somebody else to rescue him, or he could simply succeed with some setback like a minor injury. How do I choose how to proceed? Or do I let the players choose?", "Configuring dpkg stops processing when calling an HTTP request to Adobe Flash Player I recently moved to Linux, and I am in love with the experience. Opinions apart, I am having problems when running sudo dpkg --configure -a My computer stops processing the command here: You may know Adobe Flash Player is no longer supported, and I believe that could be why the command is unable to load pepperflashplugin-nonfree. I have tried fixing the problem by checking older posts here, but none of them was able to fix this problem.", "Which is the correct question (\"Who has\" vs \"Who have\")? The situation is that: We've already read three English novels. Which is the correct question for that situation? Who has already read three English novels? Who have already read three English novels? Or could both be correct? Please also provide the grammatical reasons for your answers.", "What is the probability that a person is the second person to roll a 6 for the first time? Suppose $A$, $B$, and $C$ roll a die in turns. What is the probability that $A$ is the second person to roll a $6$ for the first time?", "Let $V$ be spherically symmetric and $W$ i.i.d. Gaussian. Then $E[V|V+W=t]=g(\\|t\\|)$ A random vector $V \\in \\mathbb{R}^n$ is said to be spherically symmetric. If for every orthogonal matrix $A$ the distribution of $AV$ is the same as the distribution of $V$. My question: Let $W$ be i.i.d. zero mean Gaussian random variable. Can we show that for a spherically symmetric $V$ the conditional expectation \\begin{align} E[V|V+W=t]= g(\\|t\\|). \\end{align} That is the conditional expectation is only a function of the magnitude. My attempt: \\begin{align} E[V|V+W=t]= \\int V \\frac{f_W(t-v)}{f_{V+W}(t)} dP_V(v)= \\frac{\\int v f_W(t-v) dP_V(v)}{f_{V+W}(t)}= \\frac{E[ V f_W(t-V) ]}{f_{V+W}(t)} \\end{align} Therefore, we can show that the two functions in the above ratio only depend on $\\|t\\|$. Observe that we can write $t= \\|t\\| u_t$ where $u_t$ is a unit vector. Then, for any orthogonal matrix $A$ \\begin{align} f_{V+W}(t)=f_{V+W}(\\|t\\|, u_t)&amp;= \\frac{1}{(2\\pi)^{n/2}} E[ e^{-\\frac{\\|t-V \\|^2}{2}} ]\\\\ &amp;= \\frac{1}{(2\\pi)^{n/2}} E[ e^{-\\frac{\\|t-AV \\|^2}{2}} ]\\\\ &amp;= \\frac{1}{(2\\pi)^{n/2}} E[ e^{-\\frac{\\|tA^{-1}-V \\|^2}{2}} ]\\\\ &amp;= \\frac{1}{(2\\pi)^{n/2}} E[ e^{-\\frac{\\|t A^T-V \\|^2}{2}} ]\\\\ &amp;= f_{V+W}(tA^T)\\\\ &amp;= f_{V+W}(\\|t\\|, u_t A^T) \\end{align} Since, $A$ was arbitrary we have that $f_{V+W}(t)=h(\\|t\\|)$(i.e., only depends on the magnitute). Now I am not sure how to show that $E[ V f_W(t-V) ]$ only depends on $\\|t\\|$?", "If $11z^{10}+10iz^9+10iz-11 = 0$. Then possible value of $\\mid z \\mid,$ is If $11z^{10}+10iz^9+10iz-11 = 0$. Then possible value of $\\mid z \\mid,$ is $\\bf{My\\; Try::}$ Given $11z^{10}+10iz^9+10iz-11 = 0\\Rightarrow \\displaystyle z^9 = \\frac{11-10iz}{11z+10i}.$ Now Put $z = x+iy\\;,$ we get $\\displaystyle (x+iy)^9 = \\frac{11-10i(x+iy)}{11(x+iy)+10i} = \\frac{(11+10y)-10ix}{11x+i(10+11y)}$ Now i did not understand how can i solve it, Help Required Thanks", "If $\\left(1+\\sin \\phi\\right)\\cdot \\left(1+\\cos \\phi\\right) = \\frac{5}{4}\\;,$ Then $\\left(1-\\sin \\phi\\right)\\cdot \\left(1-\\cos \\phi\\right)$ If $\\displaystyle \\left(1+\\sin \\phi\\right)\\cdot \\left(1+\\cos \\phi\\right) = \\frac{5}{4}\\;,$ Then $\\left(1-\\sin \\phi\\right)\\cdot \\left(1-\\cos \\phi\\right) = $ $\\bf{My\\; Try::}$ Given $\\displaystyle \\left(1+\\sin \\phi\\right)\\cdot \\left(1+\\cos \\phi\\right) = \\frac{5}{4}\\Rightarrow 1+\\sin \\phi\\cdot \\cos \\phi+\\sin \\phi+\\cos \\phi = \\frac{5}{4}.$ So $\\displaystyle \\sin \\phi+\\cos \\phi+\\sin \\phi \\cdot \\cos \\phi = \\frac{1}{4}\\Rightarrow \\left(\\sin \\phi+\\cos \\phi\\right) = \\frac{1}{4}-\\sin \\phi \\cdot \\cos \\phi.$ Now $\\displaystyle \\left(1-\\sin \\phi\\right)\\cdot \\left(1-\\cos \\phi\\right) = 1-\\left(\\sin \\phi+\\cos \\phi\\right)+\\sin \\phi \\cdot \\cos \\phi =\\frac{3}{4}+\\sin 2\\phi$ Now How can I calculate $\\sin 2\\phi.$ Help me, Thanks", "Advanced statistics books recommendation There are several threads on this site for book recommendations on and but I am looking for a text on advanced statistics including, in order of priority: maximum likelihood, generalized linear models, principal component analysis, non-linear models. I've tried by A.C. Davison but frankly I had to put it down after 2 chapters. The text is encyclopedic in its coverage and mathematical treats but, as a practitioner, I like to approach subjects by understanding the intuition first, and then delve into the mathematical background. These are some texts that I consider outstanding for their pedagogical value. I would like to find an equivalent for the more advanced subjects I mentioned. , D. Freedman, R. Pisani, R. Purves. , R. Hyndman et al. , T. Z. Keith , Rand R. Wilcox , Gareth James, Daniela Witten, Trevor Hastie and Robert Tibshirani , Hastie, Tibshirani and Friedman (2009)", "How do I enable Remote Desktop connection on Xubuntu 11.10?", "Institute Name in @masterthesis Citations I need to cite master thesis and the lecture notes into a document. But the problem with @masterthesis and @unpublished citations is they don't print an institution name in the pdflatex output of bibliography. `\\documentclass{article} \\usepackage{filecontents} \\usepackage[ backend=biber, style=numeric, sortlocale=de_DE, natbib=true, url=true, doi=true, eprint=false ]{biblatex} \\addbibresource{bibliography.bib} \\begin{filecontents}{bibliography.bib} @masterthesis{bhgt, title={Bike Model}, author={Fris}, year={2016}, school={University A}, address={XXX} } @unpublished{Map, title = {Electrical Engineering Book}, author={Koch}, howpublished = {Lecture Notes}, Institution= {University B}, year = {2015} } } \\end{filecontents} \\begin{document} Citation Test: \\cite{bhgt} and \\cite{Map} \\printbibliography \\end{document}` I get this bibliography output: [1] Fris. Bike Model. XXX, 2016. [2] Koch. “Electrical Engineering Book”. Lecture Notes. 2015. Any suggestions, how we can also print an institute name?", "How can I save application settings in a Windows Forms application? What I want to achieve is very simple: I have a Windows Forms (.NET 3.5) application that uses a path for reading information. This path can be modified by the user, by using the options form I provide. Now, I want to save the path value to a file for later use. This would be one of the many settings saved to this file. This file would sit directly in the application folder. I understand three options are available: ConfigurationSettings file (appname.exe.config) Registry Custom XML file I read that the .NET configuration file is not foreseen for saving values back to it. As for the registry, I would like to get as far away from it as possible. Does this mean that I should use a custom XML file to save configuration settings? If so, I would like to see code example of that (C#). I have seen other discussions on this subject, but it is still not clear to me.", "What is the correlation if the standard deviation of one variable is 0?", "Lie bracket for Lie algebra of $SO(n,m)$", "I think this story dates from the 1950s, plus or minus a decade - I read it about 30-35 years ago in a (then) fairly old story collection. It involves explorers on a planet falling into a gelatinous object that dissolves most of their bodies except for their brains and nervous systems. About four of them fall in to the same creature, and they discover that by thinking about it they can grow limbs and other body parts. At first they try to fight each other, by growing arms so they can hit each other's brains - and one of them realises that growing a skull would be a good idea - but later they agree to grow legs and move the creature around co-operatively. I would love to identify this story.", "Why is the colour picker displaying tinted colors? The colour picker is behaving not as I expect it to. I cannot move the selector towards most of the edges, setting the RGB to 1.00 for red and the rest to 0 just gets an orange colour. Also I cannot simply keep the \"value\" the same and select a different shade, the \"value\" resets. I'm not sure if i've pressed something in error or there is a setting in the user preferences/elsewhere that needs changing. I'm using the cycles renderer. The issue occurs with any colour picking :- material, background etc. Quitting Blender and restarting does not resolve the issue. Version 2.79.6", "Are S.P.E.C.I.A.L. skills capped at 10? We know that the maximum level a dweller can train to on any SPECIAL skill is 10, however this does not consider bonuses given from their outfit. Is there any additional benefit for going over 10? For example, a dweller with an Intelligence skill of 10 wearing a lab coat that boosts Intelligence by 3? If it is a hard cap, would it be more useful to use outfits that raise a secondary characteristic instead?" ]

[ "Undefined reference to static class member Can anyone explain why following code won't compile? At least on g++ 4.2.4. And more interesting, why it will compile when I cast MEMBER to int? #include &lt;vector&gt; class Foo { public: static const int MEMBER = 1; }; int main(){ vector&lt;int&gt; v; v.push_back( Foo::MEMBER ); // undefined reference to `Foo::MEMBER' v.push_back( (int) Foo::MEMBER ); // OK return 0; }", "To my knowledge there are three types of acceleration when a body (e.g. a rod) is moving in a circle about an axis. These are: Angular acceleration : this is the rate of change of angular velocity. Tangential acceleration : this is the linear acceleration of the system in a tangential direction to the circle and equals the radius times the angular acceleration. Radial/centripetal acceleration : this is the linear acceleration of the system that is directed inwards towards the center of the circle. I also think there are two types of velocity: Linear velocity: this is its velocity in the tangential direction and is constantly changing Angular velocity or angular frequency: this is the rate of change of angle. Is the above correct? And have I missed anything?", "Increase close vote weight for gold tag badge holders In order to increase the efficiency with which poor quality questions are closed, it could make sense to have weighted close votes for a small subset of qualified users. A very good way to measure the qualified users would be to leverage the tag badges. However, it needs to be rationally limited to a set of users that are knowledgeable with the subject. A very good way to measure the top users in a tag would be to look at those who have a gold badge in the tag. If two users who have a gold tag badge pertinent to a question issue a close vote, the question should probably be closed (or probably will be very soon under the current system). I think it would make sense to allow users with a gold tag badge to have a 3x weight for close votes in those tags. Please keep in mind, this isn't suggesting full moderator one click closure. It only adds weight to the vote. A single user could not do it on their own. These singular users cast close votes all the time, so that aspect would not change. Some will vote to close, some wont, but the ones who do should have a stronger weight to their vote. Even with 3x it will require 2 of said votes to accomplish, or still 2 other users (meaning 3 agreed it should be closed - which is the same amount of high rep users it takes to delete a question and that has a much greater impact than closure). tldr; Allow gold tag badge users to have a weighted close vote in their tag", "Remove entire row in a file if first column is repeated I have a file containing two columns and 10 million rows. The first column contains many repeated values, but there is a distinct value in column 2. I want to remove the repeated rows and want to keep only one using awk. Note: the file is sorted with values in column 1. For example: 1.123 -4.0 2.234 -3.5 2.234 -3.1 2.234 -2.0 4.432 0.0 5.123 +0.2 8.654 +0.5 8.654 +0.8 8.654 +0.9 . . . . Expected output 1.123 -4.0 2.234 -3.5 4.432 0.0 5.123 +0.2 8.654 +0.5 . . . .", "NSString instance reports its class as NSCFString My objective here is really simple -- I'm trying to set an NSString to some test data, then return the class, which should be NSString. Here's my code: NSString* stringer = [NSString stringWithFormat: @\"Test\"]; NSLog(@\"%@\", [stringer class]); The log says that the class is NSCFString, not NSString. What's going on here?", "Show that conguence $\\bmod m\\,$ is an equivalence relation", "Are recommendation questions an acceptable kind of list-type question or should they be closed? Recommendations are a recurring topic on multiple Stack Exchange (SE) sites. Some sites allow recommendations (ex: ), some do not (ex: ). There are many reasons for that and I can still remember animated discussions on this subject on the Gaming meta. Then there is that existential problem with Sci-Fi SE, &quot;What problems does answering a question on this site solve?&quot; The only common problem I can think of is What to read/watch next?, which obviously led to a big number of recommendation questions, later slightly disguised as list question. And the main trouble with these questions isn't objectivity at all, some of them aren't even subjective. It's the fact that they don't have an answer - they are open ended. - Those questions are monstrously popular because: There's an actual problem to be solved, or This problem is quite common. In view of the blog post, a recommendation question fails the &quot;real questions have answers, not items or ideas or opinions.&quot; criteria. But it's still a &quot;practical, answerable questions based on actual problems that you face. &quot; and it requires expertise to answer. The problem is that there are multiple acceptable answers, and the asker is not the best person to evaluate the best answer because he doesn't know which one is the best compared to the others, and he cannot test it in short term. Even the need to accept an answer is questionable. So, is a recommendation question an acceptable kind of list-type question or should it be closed just like any other list-type questions?", "Floating point arithmetic not producing exact results", "How many square meters \"twenty feet square\" is? One would assume it to be about 2 square meters, but this is obviously not the case. In fact, I'm reading Illium by Dan Simmons. A quote follows: Much like the room they had faxed into, this space was windowless and about twenty feet square. But unlike the other room, this one was warm, lighted, and free of snow or ice. And unlike the other room, this one was almost filled with an oval metal machine about fifteen feet long. By this description, \"twenty feet square\" seems to mean 20x20 feet aka 400 square feet or 40 square meters. Given that Dan Simmons is a renowned American writer, it's not likely that he just can't speak English correctly. So, who's right and who's wrong here?", "I am just a high school student, and I haven't seen much in mathematics (calculus and abstract algebra). Mathematics is a system of axioms which you choose yourself for a set of undefined entities, such that those entities satisfy certain basic rules you laid down in the first place on your own. Now using these laid-down rules and a set of other rules for a subject called logic which was established similarly, you define certain quantities and name them using the undefined entities and then go on to prove certain statements called theorems. Now what is a proof exactly? Suppose in an exam, I am asked to prove Pythagoras' theorem. Then I prove it using only one certain system of axioms and logic. It isn't proved in all the axiom-systems in which it could possibly hold true, and what stops me from making another set of axioms that have Pythagoras' theorem as an axiom, and then just state in my system/exam \"this is an axiom, hence can't be proven\". EDIT : How is the term \"wrong\" defined in mathematics then ? You can say that proving fermat's last theorem using the number-theory axioms was a difficult task but then it can be taken as an axiom in another set of axioms . Is mathematics as rigorous and as thought-through as it is believed and expected to be ? It seems to me that there many loopholes in problems as well as the subject in-itself, but there is a false backbone of rigour that seems true until you start questioning the very fundamentals .", "$2+2 = 5$? error in proof $$\\begin{align} 2+2 &amp;= 4 - \\frac92 +\\frac92\\\\ &amp;= \\sqrt{\\left(4-\\frac92\\right)^2} +\\frac92\\\\ &amp;= \\sqrt{16 -2\\times4\\times\\frac92 +\\left(\\frac92\\right)^2} + \\frac92\\\\ &amp;= \\sqrt{16 -36 + \\left(\\frac92\\right)^2} +\\frac92\\\\ &amp;= \\sqrt {-20 +\\left(\\frac92\\right)^2} + \\frac92\\\\ &amp;= \\sqrt{25-45 +\\left(\\frac92\\right)^2} +\\frac92\\\\ &amp;= \\sqrt {5^2 -2\\times5\\times\\frac92 + \\left(\\frac92\\right) ^2} + \\frac92\\\\ &amp;= \\sqrt {\\left(5-\\frac92\\right)^2} +\\frac92\\\\ &amp;= 5 + \\frac92 - \\frac92 \\\\ &amp;= 5\\end{align}$$ Where did I go wrong", "Black screen on boot after AMDGPU-Pro install (16.04) I have been having some screen freezing issues on my new Ubuntu 16.04 system, and have been in the troubleshooting process for this issue. I thought it was a graphics driver problem, as I am running an AMD R9 380x card which was supposed to be fully supported by the open-source AMDGPU driver preinstalled with 16.04, but after looking around online, many people seem to have issues with. I thought the answer would be to install the recently released AMDGPU-Pro driver , following the instructions from . However, when I reboot I am getting a black screen. Is there an easy way to revert my changes back? My machine was semi-functional with the freezing issue but now with no video at all is useless to me. How to proceed?", "Cannot suggest retag-only edit because \"edits must be at least 6 characters\" I was trying to suggest a retag of on Seasoned Advice, but the system won't let me; I get the familiar message Edits must be at least 6 characters; is there something else to improve in this post? In general, that's not true for retagging; if you don't change the question body at all, it should work. I suspect the logic checking the edit is thrown off guard because of the title warning: The question you're asking appears subjective and is likely to be closed I found , but I cannot find any evidence (in SEDE) for invisible characters being present in the question's source. Also, that's supposed to be .", "Does it make sense to combine PCA and LDA? Assume I have a dataset for a supervised statistical classification task, e.g., via a Bayes' classifier. This dataset consists of 20 features and I want to boil it down to 2 features via dimensionality reduction techniques such as Principal Component Analysis (PCA) and/or Linear Discriminant Analysis (LDA). Both techniques are projecting the data onto a smaller feature subspace: with PCA, I would find the directions (components) that maximize the variance in the dataset (without considering the class labels), and with LDA I would have the components that maximize the between-class separation. Now, I am wondering if, how, and why these techniques can be combined and if it makes sense. For example: transforming the dataset via PCA and projecting it onto a new 2D subspace transforming (the already PCA-transformed) dataset via LDA for max. in-class separation or skipping the PCA step and using the top 2 components from a LDA. or any other combination that makes sense.", "Converse of Schur's Lemma in finite dimensional vector spaces I am trying to prove (or disprove) the converse of Schur's Lemma in finite dimensional vector spaces. I am not sure if it holds in this case, but I have tried to apply the idea that proves it in representation theory (see for example Theorem 4.3 that uses Maschke's theorem or in questions and ). The converse of Schur's Lemma in finite dimensional vector spaces is: Let $V$ be a finite dimensional vector space over the complex numbers. Let $S$ be a set of endomorphisms of $V$ and assume that every endomorphism $A$ of $V$ such that $$AB=BA\\text{ for all }B\\in S$$ is of the form $\\lambda I, \\ \\lambda\\in\\mathbb{C}$. Then $V$ is a simple $S$-space. (*an endomorphism of $V$ is a linear operator from $V$ to $V$ *$V$ is a simple $S$-space if the only $S$-invariant subspaces of $V$ are $V$ itself and the zero subspace) What I've tried so far: Assume to the contrary that $V$ is not a simple $S-$space. Then, there exists a subspace $W$ of $V$ such that $W\\not =\\{0\\}$, $W\\not= V$ and $W$ is $S$-invariant. Let $W'=V\\setminus W$. Then, since $V$ is finite, we can easily prove that $V=W\\oplus W'$ (this is my attempt to translate Maschke's theorem in vector spaces). Consequently, for every $v\\in V$, there exists unique $w\\in W$ and $w'\\in W'$, such that $v=w+w'$. Define the projection $P:V\\rightarrow V$ by $Pv=w$ for every $v\\in V$. What is left to prove is that $PB=BP$ for all $B\\in S$. Then $P$ is clearly not a scalar and thus we have the contradiction we are looking for. There is a difficulty in showing that $PB=BP$ for all $B\\in S$, because $W'$ might be $S$-invariant or not. More precisely: Let $v\\in V=W\\oplus W'$ and $v\\not =0_V$. If $v\\in W$ then $Bv\\in W$ because $W$ is $S$-invariant, therefore: $PBv=Bv$ and $BPv=Bv$. If $v\\in W'$ then $Pv=0$, hence $BPv=B\\cdot 0=0$, and (i) if $Bv\\in W'$ then $PBv=0$. (ii) if $Bv\\in W$ then $PBv=Bv$ and this is where the problem occurs. Any hints, ideas or counterexamples would be very helpful.", "I want to make a generic class that accepts only serializable classes, can it be done with the where constraint? The concept I'm looking for is this: public class MyClass&lt;T&gt; where T : //[is serializable/has the serializable attribute]", "Is it possible to use NBT tags in commands in Minecraft: Bedrock Edition?", "How can I best describe \"making a new discovery\"?", "proving $\\left(1+\\frac 1n\\right)^{n} = 1 + \\sum_{k=1}^n \\{\\frac 1{k!}\\prod_{r=0}^{k-1}(1-\\frac rn)\\}$ using the binomial theorem", "I have build a website for a finance company. The Cognito Form is on the website as an application form. I would like the information sent automatically to the finance company's email address (as soon as the form is submitted) without having to log into Cognito Forms. The finance company needs to know the exact moment the application for finance comes in. The finance company can not possibly log in to Cognito Forms 24/7 to check if there are any finance applications." ]

[ "How can I clear event subscriptions in C#? Take the following C# class: c1 { event EventHandler someEvent; } If there are a lot of subscriptions to c1's someEvent event and I want to clear them all, what is the best way to achieve this? Also consider that subscriptions to this event could be/are lambdas/anonymous delegates. Currently my solution is to add a ResetSubscriptions() method to c1 that sets someEvent to null. I don't know if this has any unseen consequences.", "Types of circular acceleration? To my knowledge there are three types of acceleration when a body (e.g. a rod) is moving in a circle about an axis. These are: Angular acceleration : this is the rate of change of angular velocity. Tangential acceleration : this is the linear acceleration of the system in a tangential direction to the circle and equals the radius times the angular acceleration. Radial/centripetal acceleration : this is the linear acceleration of the system that is directed inwards towards the center of the circle. I also think there are two types of velocity: Linear velocity: this is its velocity in the tangential direction and is constantly changing Angular velocity or angular frequency: this is the rate of change of angle. Is the above correct? And have I missed anything?", "Change \\headheight for a \\pagestyle I have a document class that auto generates header from some user input. The problem is the first page should have a different page header than the others and the headline can be multi line. So \\headheight is too small. Here is a demonstration of the problem: \\documentclass[twoside]{scrartcl} \\newcommand{\\longfirstpagehead}{% \\begin{minipage}{10cm} some\\\\long\\\\text\\\\text\\\\text\\\\text\\\\text\\\\text \\end{minipage}} \\newcommand{\\normalhead}{normal} \\usepackage{scrpage2} \\newpagestyle{firstpage}{% {\\longfirstpagehead\\hfill} %twoside links {\\longfirstpagehead\\hfill} %twoside rechts {\\longfirstpagehead\\hfill} %oneside (\\textwidth,1pt) }{% {\\pagemark\\hfill} %twoside links {\\hfill\\pagemark} %twoside rechts {\\hfill\\pagemark} %oneside } % \\newpagestyle{normal}{% {\\normalhead\\hfill} %twoside links {\\normalhead\\hfill} %twoside rechts {\\normalhead\\hfill} %oneside (\\textwidth,1pt) }{% {\\pagemark\\hfill} %twoside links {\\hfill\\pagemark} %twoside rechts {\\hfill\\pagemark} %oneside } % \\pagestyle{normal} \\AtBeginDocument{ \\thispagestyle{firstpage}} \\usepackage{blindtext} \\begin{document} %\\vspace*{1cm} \\blindtext \\blindtext \\pagebreak \\end{document} I tried to read the height with \\settototalheight and: add a \\vspace at beginning of document (unnice hack): still the bad box warning (of cause) first section has different alignment manually change \\headheight in pagestyle text height and page foot is wrong (can't change this because some scoping?) use Komascript in pagestyle \\recalctypearea warning geometry in pagestyle pretty much the same problem like the manual attemp So I would like to change the \\headheight for the pagestyle firstpage, but the page should still have the same page margins, etc. The problem is that this has to work with \\thispagestyle. (Better Ideas are also welcome) Something like \\thispagegeometry in geometry would be great. ;)", "The ending I got is : the genocide When I reset my file, my past choices still take effect. I want to start a clean run. I don't want to buy the game again, what do I do?", "Actual memory usage of a process The following are the memory usage of mysql and apache respectively on my server. As per the output of pmap say, mysql is using about 379M and apache is using 277M. [root@server ~]# pmap 10436 | grep total total 379564K [root@server ~]# pmap 10515 | grep total total 277588K Comparing this with the output of top, I see the values are almost matching. PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND 10515 apache 20 0 271m 32m 3132 S 0.0 6.6 0:00.73 /usr/sbin/httpd 10436 mysql 20 0 370m 21m 6188 S 0.0 4.3 0:06.07 /usr/libexec/mysqld --basedir=.... Now these values definitely are not the current memory usage of those two processes, since if it were it would've exceeded the 512M ram on my system and I understand the fact that these are the size of the pages assigned to these two processes and not really the size of the memory actively used by them. Now, when we use pmap -x, I see an extra coloumn Dirty which shows far less memory usage for the process. As seen in the example show below, the Dirty coloumn shows 15M as opposed to 379M in the first coloumn. My question is: Is the value under coloumn Dirty is the 'real' amount of memory actively used by that process? If its not, then how can we find out the real memory usage of a process? Not ps and top for the same reasons above. Do we have anything under /proc that will give this info? [root@server ~]# pmap -x 10436 | grep total total kB 379564 21528 15340 [root@server ~]# [root@server ~]# free -m total used free shared buffers cached Mem: 489 447 41 0 52 214 -/+ buffers/cache: 180 308 Swap: 1023 0 1023 [root@server ~]#", "Let $L,M$ two subspaces of the vector space, $V$ such that both $L,M \\ne V$. Prove: $L\\cup M \\ne V$. I think this is a case of a proof by contradiction. Lets assume $L \\cup M = V$. Hence, $$\\dim(V) = \\dim(L) + \\dim(M) - \\dim(L\\cap M)$$ How to proceed?", "Let f : A → B and g : B → C be bijections. Prove that g◦f : A → C is a bijection Can someone show me the steps I should take to solve this problem?", "How to trick a command into thinking its output is going to a terminal Given a command that changes its behaviour when its output is going to a terminal (e.g. produce coloured output), how can that output be redirected in a pipeline while preserving the changed behaviour? There must be a utility for that, which I am not aware of. Some commands, like grep --color=always, have option flags to force the behaviour, but the question is how to work around programs that rely solely on testing their output file descriptor. If it matters, my shell is bash on Linux.", "I had a look at Knuth's The Art of Computer Programming, book 1. In chapter 1, section 1.2.2, exercise 25, he presents the following algorithm for calculating logarithm: given $x\\in[1,2)$, do the following: L1: [Initialize] Set $y\\leftarrow0$, $z\\leftarrow x/2$, $k\\leftarrow1$. L2: [Test for end] If $x=1$, stop. L3: [Compare] If $x-z&lt;1$, go to L5. L4: [Reduce values] Set $x\\leftarrow x-z$, $z\\leftarrow x/2^k$, $y\\leftarrow y+\\log_b(2^k/(2^k-1))$, and go to L2. L5: [Shift] Set $z\\leftarrow z/2$, $k\\leftarrow k+1$, and go to L2. (The algorithm needs an auxiliary table which stores $\\log_b2$, $\\log_b(4/3)$, and so on, to as many values as the precision of the computer. Then Knuth concludes: this exercise is to explain why the above algorithm will terminate and why it computes an approximation of $y=\\log_b x$. Well, I see that it works, but I am not able to explain why...", "I am using Blender to mix the video from my camera with the audio from my external recording setup. It works great mostly and I am very pleased with it. But the problem is that I can't start the audio recorder an even number of thirtieths of a second from when I started the camera. And Blender seems to only let me move the audio track in the VSE by whole frames (1/30 of a second). Here are a couple screenshots: The track on top is the external audio and the one on the bottom is the camera's audio. Between the two screenshots I have only moved the audio track by one frame. But as you can see, I need to move it by about 1/2 frame to line up the audio properly with the video. So can I move a track in the VSE by fractions of a frame?", "Map of with object references as keys?", "How do I add .e00 data into my QGIS project?", "Is There Any Way to get the template Name By full URL for example If the full url is www.example.com/hello-world I need a function that return the template name (page.php) I know that WordPress matches every url with regular expression to determine the query and decide which template to include. That's exactly what I need, a built in or (custom made) function that takes the URL and returns back the corresponding template", "Redirecting stdout to a file you don't have write permission on", "How to load JAR files dynamically at Runtime? Why is it so hard to do this in Java? If you want to have any kind of module system you need to be able to load JAR files dynamically. I'm told there's a way of doing it by writing your own ClassLoader, but that's a lot of work for something that should (in my mind at least) be as easy as calling a method with a JAR file as its argument. Any suggestions for simple code that does this?", "My variables are LD_LIBRARY_PATH=/usr/lib/oracle/11.2/client64/lib ORACLE_HOME=/usr/lib/oracle/11.2/client64 How to save these variables permanently ?", "How to exclude/delete files only? Is there a way to exclude all files, in all subfolders, and keep the folder structure?", "Can you get a Windows (AD) username in PHP? I have a PHP web application on an intranet that can extract the IP and host name of the current user on that page, but I was wondering if there is a way to get/extract their Active Directory/Windows username as well. Is this possible?", "How can I set up dual monitors with nVidia?", "Converting a number with comma as decimal point to float" ]

[ "Right now is fairly broken -- it's a simple descending sort by views. As Joel said , it is &quot;a self-fulfilling prophecy.&quot; But this is not intentional, it's only because we haven't had time to improve it yet! As I sit down to write a better algorithm, I thought you guys might have some insight into what would make a good formula to determine the &quot;hot&quot; questions -- over the last 24 hours, the last week, the last month, and all time. Here are the variables we have to work with: Votes [aka Score] Views Answers Answer Votes [aka Score] Whether the question has an accepted answer or not Time question was originally asked Time of last activity on question Reputation of asker Reputation(s) of answerers Joel cited the reddit formula as an example, but I think our site is a little different than just a basic link submission site. Plus, we have more variables and data to work with. I found a describing a few formulas: Y Combinator Hacker News (p - 1) / (t + 2)^1.5 p = votes (points) from users t = time since submission in hours Reddit t = (time of entry post) - (Dec 8, 2005) x = upvotes - downvotes y = {1 if x &gt; 0, 0 if x = 0, -1 if x &lt; 0) z = {1 if x &lt; 0, otherwise x} log(z) + (y * t)/45000 Thoughts? Ideas? I don't want to overthink this; I just want the &quot;hot&quot; questions to be relevant and useful to us. So the simpler the algorithm the better! Based on my analysis of the above and the comments so far, here's the second version of what I have implemented so far. This might suck. I don't know: (log(Qviews)*4) + ((Qanswers * Qscore)/5) + sum(Ascores) -------------------------------------------------------- ((QageInHours+1) - ((QageInHours - Qupdated)/2)) ^ 1.5 Note that accepted answers weight not at all in hotness. This is intentional, as I feel accepted answers are a fine social contract, but not a good data point for question or answer quality. This algorithm will heavily favor questions with LOTS of answers, as the sum(Ascores) are now included -- one assumes if there are lots of answers, there will be a lot more voting on the answers, too. Update: Note that this formula is what is used on the linked from the homepage of each site. It is not the formula used to determine the list. See .", "Tool to create text files from a template I have to regularly create 100+ text files from templates. I currently use an overly complicated shell script. I think there is a smarter way to handle this, but I don't know how. I have a \"database\" : # outputfile template data1 data2 data3 first.txt $template_main $text1 abcd 1234 second.txt $template_main $text2 efgh 5678 third.txt $template_other $text1 ij 90 And a configuration file : template_main=main.txt template_other=other.txt text1=whatever text2=blah The templates are text files with placeholders like %%data2%% (the placeholder form can be changed). Does someone know a tool to automate this better than with a complicated shell script ?", "I would like to ask a question not about software architecture, but physical architecture, i.e., the design of buildings and other elements of the \"built environment\". I was looking for a Stack Exchange site to ask what the meaning is of the huge stone symbols on the side of the new Scottish Parliament building.", "How do you choose Spells Known when creating a new character above 1st level?", "I know how to compute modular multiplicative inverses for co-prime variables $a$ and $b$, but is there an efficient method for computing variable $x$ where $x &lt; b$ and $a$ and $b$ are not co-prime, given variables $a$, $b$ and $c$, as described by the equation below? $ a x \\equiv c \\mod b $ For example, given $ 154x \\equiv 14 \\mod 182 $, is there an efficient method for computing all the possibilities of $x$, without pure bruteforce? Please note that I'm not necessarily asking for a direct solution, just a more optimized one. I do not believe that the Extended Euclidean Algorithm will work here, because $a$ and $b$ are not co-prime. Edit: Follow up question, since the first one had a shortcut: Could the be computed efficiently as well? $12260x \\equiv 24560 \\mod 24755$. $107$ needs to be one of the computed answers.", "I need to grant select permission for all tables owned by a specific user to another user. Can I do this with a single command along the lines of: Grant Select on OwningUser.* to ReceivingUser Or do I have to generate the sql for each table with something along the lines of: Select 'GRANT SELECT ON OwningUser.'||Table_Name||'TO ReceivingUser' From All_Tables Where Owner='OWNINGUSER'", "High-end compact camera with swivel screen and running on AA batteries I'm looking for a new compact camera that: has a is small enough to be mountable on a and, runs on AA batteries. good flexibility Requirement (3) stems from the fact that I may be hiking in the wild for weeks on an end, with no opportunity to change a Lithium-Ion battery. If another solution permits me to take thousands rather than hundreds photographs on full charge, I may consider that as well. Additionally, it would be nice (but not essential) to have: the ability to handle high dynamic range a viewfinder physical buttons — I live in a cold climate, and don't like to use touch-screens The upper price range for compact models is still good for me, and I don't mind a pricerange of €400–€800 (but I don't mind cheaper either, if still of good quality). I've been the happy user of several models in the , but now my PowerShot A650 IS has died. Starting from , it seems requirement (3) kills of many cameras: the , (might also fail (2)), the , the , the ... Although enough models meet requirements (1), (2), and (4), as well as the (non-essential) additional features I listed, it seems in the past 5 years, cameras have moved away from using AA batteries. What camera models still exist that meet my requirements? Last photograph taken with my Canon PowerShot A650 IS, taking on Christmas Day 2012 in the Caldera de Taburiente, La Palma, Canary Islands, Spain.", "How to remove the \"Could not connect to the iTunes store\" error message when your network does not allow access to the iTunes Store", "Warning: Total photoshop newb! I recently got a cool image of my fiancee and I holding hands and showing off her engagment ring. The backdrop is the beach: I tried to trace an image using a combo of the laso and magic wand tools to select my target. Then I used that to pull out the target as another layer. I then pasted in a background gradient. Ended up with a really lame photoshoped looking picture. Notice the white lines where I didn't get the arms close enough and the choppy spots where I got too close. So what's my main problem here? Is their a way to bet a better cutout? Is their a blending tool that will make the background look more natural? both I tried a dozen or so tutorials I found in google searches but they just don't blend these types of images together in any of them. Thanks in advance.", "Is the Eel immortal?", "If every ideal is principal show the same is true for the image of a homomorphism.", "Meaning of $\\int\\mathop{}\\!\\mathrm{d}^4x$ What the following formula mean? $$\\int\\mathop{}\\!\\mathrm{d}^4x$$ I know that this $\\int f(x)\\mathop{}\\!\\mathrm{d}x$ is the integral of the function $f$ over the $x$ variable, but the following $\\int\\mathop{}\\!\\mathrm{d}^4x$ leave empty the argument and also have the $\\mathrm{d}$ elevated to the fourth power. What that mean? Update. In the Einstein-Hilbert action we have (note that I have understand that the other parts of the integral are relevant only after your answers, thus sorry.): $$S=\\frac{c^4}{16\\pi G}\\int\\mathop{}\\!\\mathrm{d}^4x \\, \\ R \\sqrt{-g}$$", "When to use \"click\" and \"click on\"", "What is the measure of the set of numbers in $[0,1]$ whose decimal expansions do not contain $5$?", "Java - Could not find the main class", "SQL Server 2014 - Strange SP behavior during compilation", "Force.com IDE 35.0.0.201510211056 and Force.com IDE Debugger 35.0.0.201510211056 in eclipse but it doesn't show this option to run test class, is their any way i can see it because it show the Apex_Test_Result panel but running a test class option is missing. plz help", "How do I set up an email server?", "Eclemma not offering report exportation option", "Related questions with over 99 score display incorrectly The score for the 4 questions are 111, 1218, 261 and 5 respectively, but they display 2 digits per line. This is an obvious bug in design." ]

[ "How do I remove a property from a JavaScript object? Say I create an object as follows: let myObject = { &quot;ircEvent&quot;: &quot;PRIVMSG&quot;, &quot;method&quot;: &quot;newURI&quot;, &quot;regex&quot;: &quot;^http://.*&quot; }; How should I remove the property regex to end up with new myObject as follows? let myObject = { &quot;ircEvent&quot;: &quot;PRIVMSG&quot;, &quot;method&quot;: &quot;newURI&quot; };", "Vertical spacing in floats I am using a float inside the text. As I found out, using \\intextsep I could set space above and below the float and the texts. But when I am using \\setlength{\\intextsep}{5mm}, the space below the float is more than the one above it. Why they are not equal? % Preview source code %% LyX 2.0.0beta1 created this file. For more info, see http://www.lyx.org/. %% Do not edit unless you really know what you are doing. \\documentclass[english]{report} \\usepackage[T1]{fontenc} \\usepackage[latin9]{inputenc} \\setcounter{secnumdepth}{3} \\setcounter{tocdepth}{3} \\usepackage{graphicx} \\makeatletter %%%%%%%%%%%%%%%%%%%%%%%%%%%%%% LyX specific LaTeX commands. %% A simple dot to overcome graphicx limitations \\newcommand{\\lyxdot}{.} %%%%%%%%%%%%%%%%%%%%%%%%%%%%%% User specified LaTeX commands. \\usepackage{setspace} \\setlength{\\intextsep}{5mm} \\setlength{\\belowcaptionskip}{0mm} \\setstretch{2} \\makeatother \\usepackage{babel} \\begin{document} Text Text Text Text Text Text Text Text Text Text Text Text \\begin{figure}[h] \\begin{centering} \\includegraphics[scale=0.5]{\\lyxdot \\lyxdot /Pictures/fedora} \\par\\end{centering} \\caption{} \\end{figure} Text Text Text Text Text Text Text Text Text Text Text Text \\end{document}", "Rules of thumb for divisibility Given a number presented in decimal form $n=\\sum_{k=0} d_k10^k$ there are some nice thumb rules to decide whether it is divisible with a prime number $p\\in\\{7,11,13,17,19,23,29\\}$. For each of this numbers there is a number $a_p$ such that $p|n\\iff p|(a_p\\cdot d_0+\\sum_{k=0} d_{k+1}10^k)$. $a_7=-2,\\;a_{11}=-1,\\;a_{13}=4,\\;a_{17}=-5,\\;a_{19}=2,\\;a_{23}=7,\\;a_{29}=3$ E.g. $\\;19\\cdot 17=323$ and $32+2\\cdot 3=38=2\\cdot 19$ and $32-5\\cdot 3=17$. Is there a number $a_{31}$ that works the same way? Or $a_p,\\;p\\ge37$?", "Related: I know I must describe my past and current research in my personal/research statement or statement of purpose. But do I use technical terms? I was given the advice that since the people reading my statement are mathematicians (I am applying to US for applied mathematics), they should know what I am talking about. Although I am applying to applied mathematics, it would also be nice to hear from other fields (biology, computer science, engineering etc) about this.", "is the Turkish version of mancala, with its own set of rules. I am planning on doing a project in it. Are there any game engines that either specifically play it, or universal Mancala players that plays it after supplying the options? EDIT: I am not looking for an app, but for a game engine. For example in chess, is a playing app, while is an open-source engine.", "ZF: Difference between POW and SEP?", "Was Dumbledore aware that Professor Snape took points from Harry/Gryffindor unfairly? In many situations, we see Professor Snape behave in an unfair manner. Snape unfairly and arbitrarily takes house points away from Harry/Gryffindors. Was Dumbledore aware of this and, if so, did he just not care, or did he support this to somehow help Snape's double agent role?", "General formula for evaluating integrals of the form $\\displaystyle\\int_0^\\infty x^ae^{-bx}dx$ Find a general formula for evaluating integrals of the form $\\displaystyle\\int_0^\\infty x^a e^{-bx}dx.$ I've been pondering about this question for some time. Obviously integration by parts is way too inefficient. I know there's recursion involved and maybe there's a way to find a general formula through intuition.", "Do you want to come with? Can I come with? I seem to hear this construction more often in recent years, but it still grates on my ear. I know it's often said that one shouldn't , but I class that rule along with (i.e. — pedantic tosh). Is it always informal/casual speech to end a sentence with &quot;with&quot;? Was it ever thus?", "Fast(est) and intuitive ways to look at matrix multiplication?", "I have a string that contains both double-quotes and backslashes that I want to set to a variable in Python. However, whenever I try to set it, the quotes or slashes are either removed or escaped. Here's an example: &gt;&gt;&gt; foo = 'baz \"\\\"' &gt;&gt;&gt; foo 'baz \"\"' So instead of baz \"\\\" like I want I'm getting baz \"\". If I then try to escape the backslash, it doesn't help either: &gt;&gt;&gt; foo = 'baz \"\\\\\"' &gt;&gt;&gt; foo 'baz \"\\\\\"' Which now matches what I put in but wasn't what I originally wanted. How do you get around this problem?", "What does $\\lim\\limits_{x \\to \\infty} f(x) = 1$ say about $\\lim\\limits_{x \\to \\infty} f'(x)$? Given that $f$ is differentiable, what does $\\lim\\limits_{x \\to \\infty} f(x) = 1$ say about $\\lim\\limits_{x \\to \\infty} f^\\prime(x)$ ? Intuitively I feel that it's $0$. I attempted to solve this by trying to evaluate $$\\lim_{x \\to \\infty} \\lim_{h \\to 0} \\frac{f(x + h) - f(x)}{h} $$ by trying to interchange the limits after showing that $\\frac{f(x + h) - f(x)}{h}$ converges uniformly as $x \\to \\infty$. But I couldn't proceed further. Trying to work backwards, as a specific example, $f(x) = \\arctan(x)$ came to my mind. It's derivative certainly goes to $0$ as $x \\to \\infty$. Doesn't this show that $\\frac{f(x + h) - f(x)}{h}$ converges uniformly to $0$ as $x \\to \\infty$ ? I'm totally confused! I would really appreciate if anyone told me what I am doing wrong.", "zsh: excluding files from a pattern Say I have the following files: |-- bar `-- foo |-- type_A_1 |-- type_A_2 |-- type_B_1 |-- type_B_2 |-- type_B_xx |-- type_B_xx `-- something_else I thought the following command print -l foo/*~{type_B*} would print everything under foo except things that start with type_B but it doesn't, instead it prints everything under foo: foo/type_A_1 foo/type_A_2 foo/type_B_1 foo/type_B_2 foo/type_B_xx foo/something_else I also tried print -l foo/*~type_B and got the same thing. How does the exception wildcard ~ work in zsh?", "This is a pretty simple question, at least it seems like it should be, about sudo permissions in Linux. There are a lot of times when I just want to append something to /etc/hosts or a similar file but end up not being able to because both &gt; and &gt;&gt; are not allowed, even with root. Is there someway to make this work without having to su or sudo su into root?", "How to show $\\lim_{x \\to 1} \\frac{x + x^2 + \\dots + x^n - n}{x - 1} = \\frac{n(n + 1)}{2}$? I am able to evaluate the limit $$\\lim_{x \\to 1} \\frac{x + x^2 + \\dots + x^n - n}{x - 1} = \\frac{n(n + 1)}{2}$$ for a given $n$ using l'Hôspital's (Bernoulli's) rule. The problem is I don't quite like the solution, as it depends on such a heavy weaponry. A limit this simple, should easily be evaluable using some clever idea. Here is a list of what I tried: Substitute $y = x - 1$. This leads nowhere, I think. Find the Taylor polynomial. Makes no sense, it is a polynomial. Divide by major term. Dividing by $x$ got me nowhere. Find the value $f(x)$ at $x = 1$ directly. I cannot as the function is not defined at $x = 1$. Simplify the expression. I do not see how I could. Using l'Hôspital's (Bernoulli's) rule. Works, but I do not quite like it. If somebody sees a simple way, please do let me know. Added later: The approach proposed by Sami Ben Romdhane is universal as asmeurer pointed out. Examples of another limits that can be easily solved this way: $\\lim_{x \\to 0} \\frac{\\sqrt[m]{1 + ax} - \\sqrt[n]{1 + bx}}{x}$ where $m, n \\in \\mathbb{N}$ and $a, b \\in \\mathbb{R}$ are given, or $\\lim_{x \\to 0} \\frac{\\arctan(1 + x) - \\arctan(1 - x)}{x}$. It sems that all limits in the form $\\lim_{x \\to a} \\frac{f(x)}{x - a}$ where $a \\in \\mathbb{R}$, $f(a) = 0$ and for which $\\exists f'(a)$, can be evaluated this way, which is as fast as finding $f'$ and calculating $f'(a)$. This adds a very useful tool into my calculus toolbox: Some limits can be evaluated easily using derivatives if one looks for $f(a) = 0$, without the l'Hôspital's rule. I have not seen this in widespread use; I propose we call this Sami's rule :).", "Custom Login form question In my website have two types people login one is designer another is reader, i want people come to login my website by role. Mean designer go to design login form to login. Reader go to reader login form to login. my question is: how to show two login forms in same page? how to check the role when the visiter login at the same time in login form? is it any module i can use or i need do something customize the user module and how customize? Plz help!", "Can I write the output the of time difference command to a file?", "Compiz Problems (Plugin Missing, Performance Issues, Development) I've recently set up the compiz cube again, and I was very happy to find that that flickering window glitch is gone! However, the cube reflection and deformation plugins are also gone. I am running a fresh 12.10 install, and I have every compiz plugin package installed (including compiz-plugins-extra, which supposedly contains everything that compiz-fusion-plugins-extra package used to have), but those two plugins are still missing. I haven't been able to find anyone with the same problem. Any ideas? (thanks!)", "Motivation behind the definition of ideal class group", "I was going to ask , but I came to the conclusion that I'm not going to do it (asking and building). Now my question is: why is it (usually, if we leave the silly high-end prices alone) more expensive to build a bike from scratch?" ]

[ "\"ERROR: Extra }, or forgotten \\right.\" in align* enviroment Why do I get a \"ERROR: Extra }, or forgotten \\right.\" in the following align* environment? \\begin{align*} \\int\\left[\\left(\\der{E_z}{y}-\\der{E_y}{z}-\\mu\\der{\\alpha}{t}\\right)\\alpha&amp;+\\left(\\der{E_x}{z}-\\der{E_x}{x}-\\mu\\der{\\beta}{t}\\right)\\beta\\\\ &amp;+\\left(\\der{E_y}{x}-\\der{E_x}{y}-\\mu\\der{\\gamma}{t}\\right)\\gamma\\left.\\vphantom{\\left(\\der{E_y}{x}}\\right]d\\omega=0. \\end{align*} thanks", "Can a word be contracted twice (e.g. \"I'ven't\")?", "Taxonomy terms view sorting results numerically I have a taxonomy that's comprised entirely of numeric term names, 1 through 1200 (with a few numbers missing in between). I created a new \"Taxonomy terms\" view to show all terms in this vocabulary. When I look at the view results, I'd like to see the terms sorted numerically, however the view is displaying the terms alphabetically. I understand the reason for this is because term names are strings, but I'm hoping someone has an answer of how to make the query treat the term names as integers. Here's an example of the view results as they are displayed now: 1 10 100 1000 1001 1005 101 1014 1015 1016 1019 102 1020 1024 103 1034 104 Normally in MySQL, you could write SELECT name FROM {taxonomy_term_data} ORDER BY CAST(name AS UNSIGNED). Is there a way to get this same type of CAST() happening in views?", "Why does copying the same amount of data take longer if spread across many separate files? I noticed that copying 24Mb worth of data from one folder to another took about 30 seconds because (I'm assuming this is the reason) it was over 1,000 separate files. Copying 24Mb shouldn't take so long. Why does the number of files make a different? I'm running Windows 7 on a MacBook (4GB ram, Intel(R) Core(TM)2 Duo CPU P7450 @ 2.13GHz, 32-bit Operating System) EDIT: NTFS is the file system used on the drive", "bash: alias: alias: not found", "Remotely run script on Unix, get output locally? I need to run a (Tcl, or whatever) script on a remote Unix machine, from a (local) Windows command shell, and I want the stdout/stderr of the script to show up in the Windows CLI. The exit code would also be useful. Is this possible using ssh (putty)? Or by any other means? Thanks!", "Compactness of $\\operatorname{Spec}(A)$ In an exercise in Atiyah-Macdonald it asks to prove that the prime spectrum $\\operatorname{Spec}(A)$ of a commutative ring $A$ as a topological space $X$ (with the Zariski Topology) is compact. Now because the basic open sets $X_f = \\{\\mathfrak{p} \\in \\operatorname{Spec} (A) : \\{f\\} \\not\\subseteq \\mathfrak{p} \\}$ form a basis for the Zariski Topology it suffices to consider the case when $$X = \\bigcup_{i \\in I} X_{f_i}$$ where $I$ is some index set. Then taking the complement on both sides we get that $$\\emptyset = \\bigcap_{i \\in I} X_{f_i}^c$$ so there is no prime ideal $\\mathfrak{p}$ of $A$ such that all the $f_i$'s are in $\\mathfrak{p}$. Now from here I am able to show that the ideal generated by the $f_i$'s is the whole ring as follows. Since there is no prime ideal $\\mathfrak{p}$ such that all the $f_i \\in \\mathfrak{p}$, it is clear that there is no $\\mathfrak{p}$ such that $(f_i) \\subseteq \\mathfrak{p}$ for all $i \\in I.$ Taking a sum over all the $i$ then gives $$\\sum_{i \\in I} (f_i) = (1).$$ Now here's the problem: How do I show from here that there is an equation of the form $1 = \\sum_{i \\in J} f_ig_i,$ where $g_i \\in A$ and $J$ some finite subset of $I$? This part has been giving me a headache. I am not sure if the finiteness bit has to do with algebra, topology or the fact that we are dealing with prime ideals. This is not a homework problem but rather for self-study. $\\textbf{Edit:}$ I have posted my answer below after the discussion with Dylan and Pierre.", "How to input integer value to an array, based preceeding row + column values?", "Cardinality of $\\mathbb{R}^\\mathbb{R}$ by diagonal argument I want to prove that the set of all real functions $\\mathbb{R}^\\mathbb{R}$ has a higher cardinality than the real numbers $\\mathbb R$, by Cantor's diagonal argument. I'm having difficulties with approaching this problem. What I'm looking for is a hint in the right direction. I've seen an example where it is shown that the power set $2^S$ of a countable set $S$ is uncountable, by the diagonal argument.", "How precise is the frequency of the AC electricity network? If I make a digital clock which first detects the AC frequency roughly (whether it is 50, 60, 100Hz, etc), then uses it as its clock pulse source, how precise would it be? Would it work world wide precisely? For instance, in USA, what is the mean and standard deviation of the 60Hz AC frequency?", "pass 1 environment variable using sudo Is this a correct way for passing an environment variable in sudo ? sudo -u www-data -b env FOOBAR=\"foobar\" /home/user/folder/daemon", "Is there a word that means \"a span of six months\"? That is, I want to connote a stretch of time that lasts half a year, not an event that happens every six months.", "ASP.NET Website's BIN directory and references", "Because the default 'Profile Graph' tool was not sufficient, I wrote a custom VBA script that creates scaled and exaggerated profile cross-sections in ArcGIS but I need more features: Visualize more than 1 surface Visualize vertical and directional boreholes Ability to symbolize / edit the output Linked with underlying data - changes in terrain (or profile 3D line) reflected in output A few years ago I tested an extension by A-Prime software called 'CrossView For ArcGIS' but I am not sure if it is compatible with ArcGIS 10 (Contacted A-Prime but they have not yet responded) Area there any alternatives? Other 3rd party software? A functioning script? that can do this?", "How to automate generation of image files?", "This is the profile of the object I'd like to wrap... Here is the object's profile after being wrapped... Is it possible to prevent the distortion? The following post here: did not affect my object. It seemed very promising, maybe I'm missing something? Note: I have applied the scale to both my object and curve.", "How to attach my repo to heroku app", "Determine whether the series $\\sum_{n=1}^{\\infty}(\\frac{n}{n+1})^{n^2}$ is convergent or divergent. I've tried applying all the basic tests to no avail. I need to find out what the \"trick\" for this particular series is.", "apt-get build-dep is unable to find a source package I have already followed to disable middle mouse button paste on my Ubuntu 12.04. Works like a charm. Now I am trying to achieve the same on my Linux Mint 17. When I try to sudo apt-get build-dep libgtk2.0-0 it gives me the following output: Reading package lists... Done Building dependency tree Reading state information... Done Picking 'gtk+2.0' as source package instead of 'libgtk2.0-0' E: Unable to find a source package for gtk+2.0 For me it looks like apt-get is somehow \"resolving\" 'libgtk2.0-0' to 'gtk+2.0', but then does not find any package named like that. EDIT: although I am now able to compile the program (see my answer), I still do not know what Picking 'gtk+2.0' as source package instead of 'libgtk2.0-0' is supposed to mean. Any insight on this would be appreciated, thanks!", "What is the difference between test set and validation set?" ]

[ "I read a book a while ago in which a device is invented which opens up \"tunnels\" back through time. These tunnels cannot be traveled through, but can be used to view what happened in the past. I believe it starts out narrating the invention of the device, then skips ahead to after it is widely in use. There is another device created, a cloak of sorts, which hides the user from the view of someone using the tunnel device. Does this ring a bell with anyone?", "Fine, the 's math did in the old pop-up. That makes sense. But this is just silly. Why do I need to be notified that a post I downvoted got deleted? (The title links next to the red -1s were removed from the screenshot by me. They're present in the real pop-up.) So I can break out a bottle of the '82 Rothschild? It's especially pointless because there's that caused the change. Please don't display the Rep Signal when the change is only due to someone else's deleted posts.", "I have a unique problem with an older Toshiba satellite laptop that happens to be a LegacyFree laptop meaning you can't access the bios via the normal F2, Del, Esc, etc. I can only select a boot option in the beginning such as HDD, Removeable, CD, Floppy, etc. The problem I ran into is the bootable USB I created is appearing as a bootable HDD not as a removable device and thus it is booting from the HDD in the computer because I can't change the HDD device priority. Is there anyway when making the bootable USB to make it appear as a USB instead of HDD? I've been using unetbootin and LinuxLive to create these bootable USBs. NOTE: I am aware you can access LegacyFree Bios is through a program called Tsetup or HwSetup through windowsXP problem is that The laptop doesn't have any OS currently installed.", "Ubuntu 18.04 Dock mouse hover tooltips - how to disable? I need to know if it is possible and how to disable the Ubuntu 18.04 Dock tool-tips for mouse hover the pinned application.", "I am trying to figure out how I create a downloadable PDF template of a wedding invitation design that my customers can edit themselves. They will be approx 2 fonts used on each template and the customer will need to be able to edit all text themselves. e.g. change their names, wedding date, location etc. etc. Basically I want to be able to sell an editable downloadable template. So I will need to lock the artwork and \"open\" the text so they can edit the text only. If you think of something like this image. That has artwork that I want to be uneditable and then has text that I want the customer to be able to edit and print out themselves at home etc.", "How do I make Endermen spawn more frequently? I'm playing vanilla Minecraft, and am getting ready to head to the end. I need Eyes of Ender (and hence Ender Pearls), and in my main hunting grounds (a large desert area) as little as one Enderman may spawn per night. Is there any way to \"promote\" Enderman spawning so I can get pearls more quickly?", "Show bigger amplitude of physical pendulum means bigger period Suppose you have a physical . It is true that as amplitude increases, the period increases. Can we demonstrate this fact without explicitly finding the period (which is pretty involved and pretty messy) in: an intuitive fashion, rigorously?", "Number of ways in which $5$ boys and $5$ girls are ordered in such a way that exactly $4$ girls stand consecutively in the queue Let $n$ be the number of ways in which $5$ boys and $5$ girls can stand in a queue in such a way that all the girls stand consecutively in the queue. Let $m$ be the number of ways in which $5$ boys and $5$ girls in such a way that exactly $4$ girls stand consecutively in the queue. Then find $\\frac{m}{n}$. I could find $n$ correctly as $6!\\times 5!$, but I am finding $m$ as $7!\\times 4!\\times \\binom{5}{1}$, but the book says $m$ is $6!\\times 4!\\times 5\\times \\binom{5}{4}$. Where have I gone wrong? What is the proper logic to find $m$?", "While using the mobile site on my Android phone, I saw a comment that I wanted to flag but there was no flag button. After searching, I saw that says flagging comments is not supported on mobile site. Could the ability to flag comments be added to the mobile site?", "Objects vs arrays in Javascript for key/value pairs", "Asking users to accept answer when they comment that it answers their question I've had a couple of answers today where the OP indicated via a comment that I solved their problem, but the question wasn't upvoted or accepted. In both cases the person probably wasn't able to upvote since they were new, but they could have accepted my answer. I felt a little guilty asking them to accept the answer, but since it solved their problem I felt that it would help others who stumbled on the question trying to solve their own problem to know that my solution really was the answer. Is asking the OP to accept your answer when they've said that it solved their problem a reasonable thing to do or does that feel like nagging for reputation?", "Can't install Skype 4.3 on Ubuntu 14.04 64 bit First of all, I think this question is not duplicated, because I have tried all other solutions I found here, but nothing solved my problem. I use Ubuntu 14.04 64 bit. I have tried until now: sudo apt-get install skype -> It didn't work. The error was: The following packages have unmet dependencies: skype : Depends: skype-bin E: Unable to correct problems, you have held broken packages. I have tried sudo dpkg add-architecture &amp;&amp; sudo dpkg -i skype-ubuntu-precise_4.3.0.37-1_i386.deb but it didn't work either. The error was: dpkg: dependency problems prevent configuration of skype: skype depends on libqt4-dbus (&gt;= 4:4.5.3); however: Package libqt4-dbus is not installed. skype depends on libqt4-network (&gt;= 4:4.8.0); however: Package libqt4-network:i386 is not installed. skype depends on libqt4-xml (&gt;= 4:4.5.3); however: Package libqt4-xml:i386 is not installed. skype depends on libqtcore4 (&gt;= 4:4.7.0~beta1); however: Package libqtcore4:i386 is not installed. skype depends on libqtgui4 (&gt;= 4:4.8.0); however: Package libqtgui4:i386 is not installed. skype depends on libqtwebkit4 (&gt;= 2.2~2011week36); however: skype depends on libstdc++6 (&gt;= 4.2.1); however: Package libstdc++6:i386 is not installed. skype depends on libx11-6; however: Package libx11-6:i386 is not installed. skype depends on libxext6; however: Package libxext6:i386 is not installed. skype depends on libxss1; however: Package libxss1:i386 is not installed. skype depends on libxv1; however: Package libxv1:i386 is not installed. skype depends on dpkg: error processing package skype (--install): dependency problems - leaving unconfigured Processing triggers for hicolor-icon-theme (0.13-1) ... Processing triggers for gnome-menus (3.10.1-0ubuntu2) ... Processing triggers for desktop-file-utils (0.22-1ubuntu1) ... Processing triggers for bamfdaemon (0.5.1+14.04.20140409-0ubuntu1) ... Rebuilding /usr/share/applications/bamf-2.index... Processing triggers for mime-support (3.54ubuntu1) ... Errors were encountered while processing: skype I have tried to use after sudo apt-get -f install but it didn't solve the issue. I have tried to install by using Gdebi. The error was: Cannot install 'libqtwebkit4:i386' I have tried to install using Ubuntu Software Center. The error was: Cannot install 'libqtwebkit4:i386' I have tried changing the server in \"Software and Updates\". I have tried to use \"Main Server\" and \"Servers for United States\". But it couldn't solve my problem. Anyone has any idea how to solve that? SOLVED Well, I formatted my pc and I installed Skype first of all. Probably another installation that I had done before the Skype installation was the problem, i guess. Thanks people!", "'longtable' caption without incrementing 'table'? For reasons both complex and confusing, I would like to caption a longtable without incrementing the table counter in the process. I want to have two consecutive longtable environments to be captioned with identical table numbers; i.e. one longtable captioned \"Table x.y: Data Set (Part A)\" and one captioned \"Table x.y: Data Set (Part B)\", with x.y being identical for both tables. Apparently however, even \\caption*{} command bumps table. I am a bit at a loss here. Note: I know that the xtab package would enable me to have one long table with switches of headers and captions mid-table. However I got a (different) problem with that package, akin to but sadly not solved by egreg's answer there; so this question should be considered longtable-only as xtab, supertabular etc. don't float my boat right now. :-(", "How can I solve \"Be aware that removing the lock file is not a solution and may break your system\"? I did: sudo apt-get update I got this: Reading package lists... Done E: Could not get lock /var/lib/apt/lists/lock. It is held by process 1131 (packagekitd) N: Be aware that removing the lock file is not a solution and may break your system. E: Unable to lock directory /var/lib/apt/lists/ I used to just remove the lock file, but I've never seen that note before (did it break my system?)?? What do I do?", "How to deal with \"java.lang.OutOfMemoryError: Java heap space\" error?", "I followed Mike's solution from my first question: My next question is how to add entries (for the abstract and acknowledgements pages) into the table of contents.", "Why is len(Posts.body) incorrect on answers in data.SE? I was trying to find a longest answer on a site, and ran into a weird discrepancy: shows that has a length of 36388 (length in the query is defined as LEN(Posts.Body)) Yet, the post clearly only has ~26000 characters, as measured 2 ways: Copy/pasting full text of the answer in my text editor gives me 26040 characters (the source of the answer with all the markdown, not the rendered text which is even smaller). Trying to post a new answer that consists of this answer's text twice gives me an error &quot;Body is limited to 30000 characters; you entered 52258&quot; - meaning that the length is under 26100 (not 100% sure where the difference in counts comes from as far as two methods) Another example from same query: shows len(body) of 33738 whereas the text of the answer has only 29000 characters. This clearly isn't showing rendered characters, as the rendered character count is LOWER than actual answer text when editing (e.g. links add characters, as do images). How can this data.SE discrepancy be explained?", "Is \"performance\" singular or also plural?", "Why should I install hardware drivers if my computer is working fine? I've just installed Windows 7 on my PC. I went online to look for drivers. For , Foxconn offers LAN drivers, on-board audio drivers, and chipset drivers. And for , Nvidia offers a graphics card driver, obviously. But then I stopped and wondered... what benefit would I gain from installing them? The LAN cable is plugged in and I'm online; no problems there. The on-board audio is working fine. A quick Google tells me that a chipset is responsible for moving data around my motherboard – which seems to be happening OK! And my graphics look perfect. So why should I install the drivers? What would they give me, other than badly designed \"management\" interfaces, and pointless \"notifications\" whenever I plug in an audio jack? If there are different considerations for each of the components – chipset, audio, LAN, and graphics (and any others you think I should be aware of) – please break it down in your answer. Update: I've had a couple of answers already, saying that I'll get better stability, bugfixes, etc. Can I slightly expand my question... Can I get all these same benefits if I install the drivers via Windows Update? And if I do this, would I avoid having to install the vendor-specific UIs, which I find so annoying?", "I will give this question a little context. Firstly, as I understand it, as soon as I \"close the switch\" on a circuit, electric current pretty quickly establishes a steady state where, at any given cross section along a wire, the average kinetic energy of that slice is both constant and equal anywhere along the wire. (Please correct me if I am misunderstanding). If the average kinetic energy is constant anywhere throughout the wire in the circuit (which confuses me, as I would think that the electrons should all accelerate after exiting the resistor since they are no longer being impeded as much), that means that the average velocity is constant. So, in the example of a simple circuit with a battery of v Volts and a resistor of o Ohms, my question is the following: Because a 'voltage drop' is known to occur across the resistor, what type energy is being \"traded\" to generate the heat that radiates from the resistor? I would think that the reflexive answer is \"electrical energy\"...hence the VOLTAGE drop (the sacrificed energy is clearly not kinetic, as the velocity is constant everywhere). However, I find this confusing. Does this mean that if I had a positive test charge, it would be easier for me to bring it to the beginning of the resistor as compared to bringing it to the end of the resister? Further, if the correct answer IS \"electrical energy\", why exactly DOES electrical energy get \"dissipated\" as the electrons pass through the resistor? I always here the comment Oh! It's because all the electrons are running into densely packed crap which impedes their flow but that to me sounds like a reason for their KINETIC energy to be reduced. However, clearly that's not the case. So, ultimately, I guess the real question is: **What goes on in the resistor that is literally removing electrical energy **. I am sure that this is a quantum mechanics question, but my quantum mechanics knowledge is not terribly strong. If I could get an answer that is devoid of crazy wave function equations, I would greatly appreciate it. Thanks!" ]

[ "How to vote on friends / colleagues ' questions (or answers) Almost every time a colleague of mine asks a question, we have discussed this problem beforehand. Also, we sometimes meta-discuss the question for stackoverflow (why did I get the &quot;this might be subjective&quot; warning, is this understandable enough, etc). This is less so with answers, but I could believe for some groups this works the same. For now I'll stick to questions, but you could s/question/answer if you like. The resulting question is almost always Interesting for me, and a problem I don't know the answer to. I probably would favorite it According to me a valid and good question (as we talked about it beforehand) I would probably want to upvote it. Now I believe to read that &quot;ring voting&quot; is a thing, and I tried to find some questions about this, but didn't find many. I did find and read this blogpost from 2008: . It reads to me that upvoting 'fraud' is more commonplace then downvoting and it might seem anomalous that I would upvote almost all questions from one user. If all colleagues would do this to their team, you'd get some mediocre questions getting a lot of votes, and some users getting a lot of attention, points etc from that. If you would -as seems to be done -, sort the amount of upvotes for my colleague, you'd get me being 'anomalous' in front of the crowd. On the other hand, as explained above, I do want to upvote almost all stuff some of my colleagues put on here for (I believe) the right reasons: they are questions I consider good and interesting. It's just that I know of all their questions (as they tell me about them), which obviously isn't the case for a random user. So what is the deal? When is upvoting content from one user frowned upon? Would my usecase be in danger of being a (what I consider 'false') positive for the fraud-detection? (and would you agree with that or not) How to prevent this false positive (if you agree with me it is one, otherwise this is a moot question) -&gt; As noted in the comments: I'm not looking for tricks, so an answer could be &quot;don't vote for your colleagues&quot;. I agree that there should be no to 'tricks' around that could be used for real fraud of course", "Math notation in LaTeX? How can I write e^(3j) in LaTeX? I have tried many syntax, like $e^(3j)$ or $e^*{3j}$ Any help will be very well received.", "Approximation algorithms for min vector subset-sum over GF(2) In vzn asked about the following problem, which I'll call Vector-Subset-Sum. Given a set of vectors $v_i$ over GF(2) and a target vector $y$, is there a subset of the $v_i$ summing to $y$? In the answers, comments, and referenced papers I noted The decision problem is in P. The natural minimization problem (finding the smallest subset) is NP-hard. It's related to the problem of finding sparse codewords in a linear code. My question is: are there any known polynomial-time approximation algorithms for the minimization problem in (2)? I know very little about coding theory, so there may be some obvious or well-known approximation-preserving reductions to (3) that I have not seen.", "Injectivity and surjectivity of a recursive function Let $f:\\mathbb{N} \\to \\mathbb{Q}^+$ defined as follows : $$\\begin{cases} f(0) = 0 \\\\ f(2n) = \\dfrac{1}{f(n)+1} \\\\ f(2n+1) = f(n)+1 \\end{cases}\\,.$$ It is asked to prove the injectivity then the surjectivity of $f$. After examining first values taken by $f$, I proved by induction that $f(2^k)=\\dfrac{F_k}{F_{k+1}}$ where $(F_n)$ is the fibonacci sequence. Also one notes that if $m$ and $n$ have different parity then we can't have $f(m) = f(n)$ since $f(2\\mathbb{N}) \\subset (0,1)$ and $f(2\\mathbb{N}+1) \\subset [1,+\\infty)$. Any ideas on how to finish the proof of injectivity and any thoughts about surjectivity are welcome. Thanks", "How to calculate the integer part of the value of the following equation? $$y=1+\\frac{1}{\\sqrt{2}}+\\frac{1}{\\sqrt{3}}+\\frac{1}{\\sqrt{4}}+\\ldots+\\frac{1}{\\sqrt{1000000}}$$ It should be calculated in a special way, after all the equation is so long.", "How to permanently set environmental variables My variables are LD_LIBRARY_PATH=/usr/lib/oracle/11.2/client64/lib ORACLE_HOME=/usr/lib/oracle/11.2/client64 How to save these variables permanently ?", "Avoiding \"(Not Responding)\" label in windows while processing lots of data in one lump I occasionally need to process a large amount of data from one package off the network, which takes sufficiently long that when the user tries to interact with the application windows adds the \"(Not Responding)\" string to the window title. I am aware this is because the processing is being done within a call to handle a message (some way up the stack) and therefore is blocking the message pump. I'm also aware the ideal way to deal with this is to process the data asynchronously in a separate thread so the pump can continue running, however this is a LARGE desktop application which is single threaded from top to toe and safely spinning this processing off is not feasible in our time frame. So with that in mind, is there by any chance a way I can at least avoid the \"not responding\" moniker (which to most users reads as \"has crashed\") by telling windows my application is about to be busy before I begin the work? I believe there is something along these lines when responding to a request to close, one can keep asking windows for more time to avoid it proclaiming that your not \"closing in a timely fashion\" I should add this is a C++ MFC application.", "Why do I get \"warning longer object length is not a multiple of shorter object length\"?", "How do I mention my own products in answers? Twice now I've seen questions on Stack Overflow where one of my company's products might provide an answer to the question. One was a slightly vague connection about object-relational mapping, but the other was a specific question about workshop/event management where we have a product which is almost an exact match for the questioner's needs. Of course the questioner should take a pinch of salt with anything I say about it, but it might be useful to have the product brought to his attention as one possible solution. What are the rules and guidelines about answering with something I worked on?", "Is save data from previous Dragon Age games used in Inquisition? Does Dragon Age Inquisition make use of save data from previous games in the series? If so, what benefits does this provide?", "Include Watir test cases in a Continuous Integration system", "Understanding the Basic Context of Trusted Hosts I got the trusted host settings error. The trusted_host_patterns setting is not configured in settings.php. This can lead to security vulnerabilities. It is highly recommended that you configure this. See Protecting against HTTP HOST Header attacks for more information. I read the but I'm not understanding some of the basic context. Are the \"trusted hosts\" me and other administrators who want to be able to administer the site remotely? If so, would I add my PC's domain to the trusted host list?", "Computer unstable at lower temperatures My computer is playing some strange joke at me, and I'm at a loss. Everybody knows that hot temperatures causes many components to become unstable and even cause damage. When I built this machine, I was careful to do a bunch of experiments with different airflow configurations, with CPU-and-GPU intensive benchmarks running, and measuring the temperature at different points to find the best configuration. Generally, the internal temperature of this machine is very close to ambient temperature (with 2 exceptions: the GPU always runs ~10°C above ambient, and the CPU goes to at most ~12°C above ambient when running CPU-intensive applications). Now comes the problem: at really cold mornings. At cold mornings (~10°C (50°F) or below), the system shows really strange general instability. Beeps from the BIOS, the operating system displays strange messages about memory corruption and PCI devices that failed to initialize, and then, everything hangs. The computer hangs to the point that all USB devices turn of. Hitting the Reset button blanks the screen but the mainboard fails to proceed to the boot. I never thought that low temperatures could cause computer instability. And 10°C is not that cold, it is still within operating temperatures of all components as far as I checked. I'm quite sure it is related with the temperature. There were too many cold and warm mornings that demonstrated that the problem only showed in the cold ones. I'm working around this problem by letting the computer sit at the GRUB menu for some 5-10 minutes before letting the OS start, or blowing hot air inside the case if I'm in a hurry. I don't know what should I approach next to find the source of this problem. Since it is difficult to reproduce (I need a cold morning, and the computer must be cooled down (powered off for many hours)), I need to plan ahead the experiment, since it stabilizes after a few minutes on. Machine is an ASUS P5VDC-X equipped with Intel P4 64-bit 3GHz, 2GB of DDR2 RAM, a 500W PSU and an nVidia GeForce 9600GT. Everything else was already disconnected/removed before and the problem persisted, so the problem should be in one of these remaining parts. Any help is appreciated!", "How to access an object from another class?", "I hope this is not a repeat question. I tried searching but couldn't come up with the right search words for this question. I see the following in the sidebar of my flagging history tab: I notice that I have raised 28 helpful flags from my user page, but I see \"27 deemed helpful\" and \"1 deemed helpful\". What is the difference between the top half and the bottom half of the entries in the flagging history sidebar? How should I interpret the results displayed in the sidebar?", "Is there a word for someone who has others do all their work for them? In a way like a slave master. More though like say someone who had robots do all their work and they were never themselves productive and had no drive. If you've read R.U.R. you'll understand the question better. I'm looking for a word with more definition than just lazy. Update 1: It think I may actually go with drone if anything. I think that definition fits what I'm looking for the best. I also liked the definition of the British term layabout that one person mentioned, but I will probably use drone. Thanks for all the help and sorry if I was confusing or unclear. Update 2: I needed this word for use in an essay I was writing which I have now handed in. Thanks for the help guys. No more suggestions needed.", "creating a tar archive without including parent directory I am trying to create a graphical program for my script. Inside the script I use tar to create a tar archive. From the graphical program I get the full name of file that I want to create a tar archive. tar -cvf temp.tar /home/username/dir1/dir2/selecteddir My tar archive includes home, username, dir1, dir2 and selecteddir while i want tar to create archive only including selecteddir.", "Trying to identify pre-1970s short story involving multiple humans absorbed into an alien blob", "Is there an easy way to create ordinals in C#?", "A diagram which is not the torus At page 17 of Munkres' Elements of Algebraic topology it says, referring to fig. 3.6, that \"the diagram does not determine [the torus]. It does more than paste opposite edges together\": Is it so? I tried to glue them together, but end up with a normal torus." ]

[ "So this has been an on-going saga the last few days, and I've already posted several related questions here, and I am feeling quite defeated. I have/had a beautiful 16\" cast iron dutch oven from Cabelas. I took it out for a test spin the other night (I had completed all seasoning steps that the Google Gods recommended). Then: I tried (and failed spectacularly) to cook a pork roast in it, but cooked it at way too hot a temperature and burned/charred/fused the animal fats/juices into the oven, whereby it basically baked into the cast iron (related question ) I tried cleaning/scrubbing it with coarse-grained salt -> did nothing Then I tried cleaning it with dishwashing liquid + salt -> did nothing Then I let the whole thing soak in a vat of a 50/50 mixture of water + white vinegar -> took all the tarry slude off, stripped some seasoning off (revealing bare iron), but in 80% of the burned/charred areas, still did nothing Then I went to town on it with a steel wool and salt and dishwashing liquid and was left with some smooth, properly seasoned surfaces, and some more areas stripped down to bare metal I decided to just re-season it. So I scrubbed it one last time (about 1 hour ago) with a steel wool and some water, got all the rust and remaining crud off (finally), and built a fire. I placed it on the hot coals of the fire and let it sit there for 15 mins. My intention (whether misled or not) was to burn off all the remaining water from when I had previously washed/scrubbed it, then let it cool off, then season it with oil, and then bake it for a few hours. So I just took the oven off the fire and opened the lid...and the entire inside is covered in rust. An hour ago there was none. When I put the oven into the fire 15 mins prior, there had been none (yes, I checked) This just came out of nowhere. I'm ready to give up, unless anyone can offer some concrete set of steps for me that will salvage this $100 rust bucket. How can I get rid of the rust and then re-season this before more rust sets in? Meh...", "Finding inverse of polynomial in a field I'm having trouble with the procedure to find an inverse of a polynomial in a field. For example, take: In $\\frac{\\mathbb{Z}_3[x]}{m(x)}$, where $m(x) = x^3 + 2x +1$, find the inverse of $x^2 + 1$. My understanding is that one needs to use the (Extended?) Euclidean Algorithm and Bezout's Identity. Here's what I currently have: Proceeding with Euclid's algorithm: $$ x^3 + 2x + 1 =(x^2 + 1)(x) + (x + 1) \\\\\\\\ x^2 + 1 = (x + 1)(2 + x) + 2$$ We stop here because 2 is invertible in $\\mathbb{Z}_3[x]$. We rewrite it using a congruence: $$(x+1)(2+x) \\equiv 2 \\mod{(x^2+1)}$$ I don't understand the high level concepts sufficiently well and I'm lost from here. Thoughts? Wikipedia has a page on this we a , but it's still not clear in my mind. Note that has almost the same title, but it's a level of abstraction higher. It doesn't help me, as I don't understand the basic concepts. Thanks.", "Equation number enclosing parentheses misplaced with Polyglossia+Hebrew+amsmath", "I'm using the plugin which registers it's own post type but the capability is assigned to \"post\". I want to change it to \"manage_options\". Is there a correct way without altering the plugin to do that? Calling a hook, a function or whatever? public function register_post_type() { $labels = array ( 'name' =&gt; _x( 'Custom Code', 'post type general name' ), 'singular_name' =&gt; _x( 'Custom Code', 'post type singular name' ), 'menu_name' =&gt; _x( 'Custom CSS &amp; JS', 'admin menu' ), 'name_admin_bar' =&gt; _x( 'Custom Code', 'add new on admin bar' ), 'add_new' =&gt; _x( 'Add Custom Code', 'add new' ), 'add_new_item' =&gt; __( 'Add Custom Code' ), 'new_item' =&gt; __( 'New Custom Code' ), 'edit_item' =&gt; __( 'Edit Custom Code' ), 'view_item' =&gt; __( 'View Custom Code' ), 'all_items' =&gt; __( 'All Custom Code' ), 'search_items' =&gt; __( 'Search Custom Code' ), 'parent_item_colon' =&gt; __( 'Parent Custom Code:' ), 'not_found' =&gt; __( 'No Custom Code found.' ), 'not_found_in_trash' =&gt; __( 'No Custom Code found in Trash.' ), ); $args = array ( 'labels' =&gt; $labels, 'description' =&gt; __( 'Custom CSS and JS code' ), 'public' =&gt; false, 'publicly_queryable' =&gt; false, 'show_ui' =&gt; true, 'show_in_menu' =&gt; true, 'menu_position' =&gt; 100, 'menu_icon' =&gt; 'dashicons-plus-alt', 'query_var' =&gt; false, 'rewrite' =&gt; array ( 'slug' =&gt; 'custom-css-js' ), 'capability_type' =&gt; 'post', // &lt;--- I want to manipulate this 'has_archive' =&gt; true, 'hierarchical' =&gt; false, 'exclude_from_search' =&gt; true, 'menu_position' =&gt; null, 'can_export' =&gt; false, 'supports' =&gt; array ( 'title' ), ); register_post_type( 'custom-css-js', $args ); } The above code is in custom-css-js.php lines 200-239.", "What would be the value of $\\sum\\limits_{n=0}^\\infty \\frac{1}{an^2+bn+c}$ I would like to evaluate the sum $$\\sum_{n=0}^\\infty \\frac{1}{an^2+bn+c}$$ Here is my attempt: Letting $$f(z)=\\frac{1}{az^2+bz+c}$$ The poles of $f(z)$ are located at $$z_0 = \\frac{-b+\\sqrt{b^2-4ac}}{2a}$$ and $$z_1 = \\frac{-b-\\sqrt{b^2-4ac}}{2a}$$ Then $$ b_0=\\operatorname*{Res}_{z=z_0}\\,\\pi \\cot (\\pi z)f(z)= \\lim_{z \\to z_0} \\frac{(z-z_0)\\pi\\cot (\\pi z)}{az^2+bz+c}= \\lim_{z \\to z_0} \\frac{\\pi\\cot (\\pi z)+(z_0-z)\\pi^2\\csc^2 (\\pi z)}{2az+b} $$ Using L'Hopital's rule. Continuing, we have the limit is $$ \\lim_{z \\to z_0} \\frac{\\pi\\cot (\\pi z)+(z_0-z)\\pi^2\\csc^2 (\\pi z)}{2az+b}= \\frac{\\pi\\cot (\\pi z_0)}{2az_0+b} $$ For $z_0 \\ne 0$ Similarly, we find $$b_1=\\operatorname*{Res}_{z=z_1}\\,\\pi \\cot (\\pi z)f(z)=\\frac{\\pi\\cot (\\pi z_1)}{2az_1+b}$$ Then $$\\sum_{n=-\\infty}^\\infty \\frac{1}{an^2+bn+c} = -(b_0+b_1)=\\\\ -\\pi\\left( \\frac{\\cot (\\pi z_0)}{2az_0+b} + \\frac{\\cot (\\pi z_1)}{2az_1+b}\\right)= -\\pi\\left( \\frac{\\cot (\\pi z_0)}{\\sqrt{b^2-4ac}} + \\frac{\\cot (\\pi z_1)}{-\\sqrt{b^2-4ac}}\\right)= \\frac{-\\pi(\\cot (\\pi z_0)-\\cot (\\pi z_1))}{\\sqrt{b^2-4ac}}= \\frac{\\pi(\\cot (\\pi z_1)-\\cot (\\pi z_0))}{\\sqrt{b^2-4ac}} $$ Then we have $$\\sum_{n=0}^\\infty \\frac{1}{an^2+bn+c} = \\frac{\\pi(\\cot (\\pi z_1)-\\cot (\\pi z_0))}{2\\sqrt{b^2-4ac}}$$ Is this correct? I feel like I made a mistake somewhere. Could someone correct me? Is there an easier way to evaluate this sum?", "What vintage movie had this blue floating holographic head talking to some kind of military installation?", "What do you recommend as an optimal point and orientation for mounting a rear-view mirror? I'm open to handlebar-, glasses-, or helmet-mounted. Some of the considerations, as I understand it, are: Ease of mounting. View provided. Vibration. Likelihood of breaking. Robustness for repeated off and on (for glasses-mounted). I've got a hybrid bike with flat handlebars. I'd also welcome specific product recommendations and recommendations about other aspects to look for in a mirror.", "Forcing smoothness of regression coefficients", "I can only move the origin point of the mesh that I selected in object mode, but not the whole mesh Did I set anything up by accident?", "Why use Chef/Puppet over shell scripts? New to Puppet and Chef tools. Seems like the job that they are doing can be done with shell scripting. Maybe it was done in shell scripts until these came along. I would agree they are more readable. But, are there any other advantages over shell scripts besides just being readable?", "Suppose I have two tables that don't have many columns (3, for example). How can I position them side by side?", "how to make a regex string reject a blank field", "The most common way to refer to non-immediate family?", "Make clear which profile data is visible to whom", "How to prove or disprove $\\forall x\\in\\Bbb{R}, \\forall n\\in\\Bbb{N},n\\gt 0\\implies \\lfloor\\frac{\\lfloor x\\rfloor}{n}\\rfloor=\\lfloor\\frac{x}{n}\\rfloor$. How to prove or disprove $\\forall x\\in\\Bbb{R}, \\forall n\\in\\Bbb{N},n\\gt 0\\implies \\left\\lfloor\\frac{\\lfloor x\\rfloor}{n}\\right\\rfloor=\\left\\lfloor\\frac{x}{n}\\right\\rfloor$. So we want to prove $\\left\\lfloor\\frac{\\lfloor x\\rfloor}{n}\\right\\rfloor\\ge\\left\\lfloor\\frac{x}{n}\\right\\rfloor$ and $\\left\\lfloor\\frac{\\lfloor x\\rfloor}{n}\\right\\rfloor\\le\\left\\lfloor\\frac{x}{n}\\right\\rfloor$ Since $\\lfloor x\\rfloor\\le x$, we can just start from here and prove $\\left\\lfloor\\frac{\\lfloor x\\rfloor}{n}\\right\\rfloor\\le\\left\\lfloor\\frac{x}{n}\\right\\rfloor$ But for $\\left\\lfloor\\frac{\\lfloor x\\rfloor}{n}\\right\\rfloor\\ge\\left\\lfloor\\frac{x}{n}\\right\\rfloor$, I have no idea how to start.", "Using apt-get how to check have installed latest version ? Hello im just new for Linux I know that sudo apt-get is for installing application but how I would know that I have installed the latest version of the application for example apt-get install sun-java6-jdk is there an option to upgrade or see the latest version or its ok to install an old version the application and Linux will upgrade it for me ?", "Implementing i18n string translation in a custom module? I have a custom module I've built which essentially acts as a repository of custom CTools keywords that users can arbitrarily define. The issue I'm facing is I need to be able to translate these user-defined strings, so I think I need to implement string translation using the i18n_string module. I have never worked with translation or localization before, so I'm a bit lost with regards to going about how to implement this. I think I'm on the right path with i18n_string though. Can someone experienced with i18n provide examples that I can look at so I can learn the proper way to implement this?", "I recently updated my profile bio (from Arqade) and clicked 'Save and copy changes to all public communities'. This appears to have broken/reset my profile picture on all but Arqade. Note that I did not update my profile picture as part of my changes. Arqade: Meta SE for comparison: I haven't touched my profile picture in years. Is this a bug? Update: It appears my profile pic across all communities has been set back to 'Identicon'. I went on to Stack Overflow and changed my profile picture back to 'Gravitar' and clicked 'Save and copy to all communities' again, but this did not update my profile picture anywhere but SO. (I did the same on Sustainability to be doubly sure). Update 2: This is a persistent bug - I had changed most of my SE communities back to my 'Robotnik' display pic over the past little while. Today I edited my profile again on Arqade, Clicked 'Save and copy' - and the display pic reverted back to identicon again across all sites. Update 3: I have re-uploaded my profile picture and the 'Save and copy' function worked. It appears that this is actually a bug to do with the old images from Gravatar.", "Is there a word or phrase for something that one might wish exists, but most certainly doesn't?", "The Python docs say: re.MULTILINE: When specified, the pattern character '^' matches at the beginning of the string and at the beginning of each line (immediately following each newline)... By default, '^' matches only at the beginning of the string... So what's going on when I get the following unexpected result? &gt;&gt;&gt; import re &gt;&gt;&gt; s = \"\"\"// The quick brown fox. ... // Jumped over the lazy dog.\"\"\" &gt;&gt;&gt; re.sub('^//', '', s, re.MULTILINE) ' The quick brown fox.\\n// Jumped over the lazy dog.'" ]

[ "How do I show that the equation $x^3+10x^2-100x+1729$$=0$ has at least one complex root $a$ such that $|a|$$&gt;$$12$.", "On , I have my favorite tags filter. I setup email notifications for it and now I'm thinking I overdid it on the frequency. Trying to change the settings, I clicked on the edit link in the email notifications box to the right, except nothing happens. There are no JavaScript errors and the HTML for the link is simply &lt;a class=&quot;edit&quot;&gt;edit&lt;/a&gt;. This seems like unfinished planned feature. Update: Using Chrome Version 29.0.1547.66 m Same on Firefox 23.0.1 Both edit links are not working. Further Update Events capture: Update 2014-02-03: Here's what the subscription tab in the network profile looks like.", "How can I make two objects interact I am making an animation where a person sits down on sofa. I need to make it such that when the person sits on the sofa or presses it with his hand, it deforms. However in my case, when he presses on the sofa, his hands goes trough the sofa. How can I fix this problem?", "Duplicates of duplicates should be remapped I noticed today another example of duplicates of duplicates: that (A) was closed as a duplicate of (B), but one day later (B) was closed as duplicate of (C). Sometimes I need to click many times from one question to another until I get to the master question. I think that it's better if the question (A) is closed as duplicate of (C), and even if (B) has already (helpful) answers, (B) and (C) could be merged. Is it possible to remap all duplicates to the master question, just like the tag synonyms?", "Which is right: \"In one of the computers\" or \"On one of the computers\"?", "Is it safe to travel to Miami Beach shortly after hurricane Irma? Two months ago my girl and I booked our vacation. We are from Berlin, Germany and wanted to see the U.S. Our first stop is Miami Beach at the 15th and we want to stay there for 3 days and continue to NYC. Later on we will go to Vegas and come back to Miami the 26th of September and stay there another 4 nights. I expect the hurricane will be gone by the 15th, but I have no idea whether it will be okay. For me okay means that we can reach our hotel and sleep there. What do you suggest? I know this question is primarily opinion based, but here in Germany we don't have hurricanes and I don't know how fast the state will recover.", "Eclipse returns error message \"Java was started but returned exit code = 1\"", "Bash variable scope Please explain to me why the very last echo statement is blank? I expect that XCODE is incremented in the while loop to a value of 1: #!/bin/bash OUTPUT=\"name1 ip ip status\" # normally output of another command with multi line output if [ -z \"$OUTPUT\" ] then echo \"Status WARN: No messages from SMcli\" exit $STATE_WARNING else echo \"$OUTPUT\"|while read NAME IP1 IP2 STATUS do if [ \"$STATUS\" != \"Optimal\" ] then echo \"CRIT: $NAME - $STATUS\" echo $((++XCODE)) else echo \"OK: $NAME - $STATUS\" fi done fi echo $XCODE I've tried using the following statement instead of the ++XCODE method XCODE=`expr $XCODE + 1` and it too won't print outside of the while statement. I think I'm missing something about variable scope here, but the ol' man page isn't showing it to me.", "How do I insert the total continuation count in the allowframbreaks frame title? I would like to change the numbering of allowframbreaks frame, for instance, from I II III to (1/3) (2/3) (3/3)， but fail to find out a command to get the total continuation count. Here is the MWE. \\documentclass[compress]{beamer} \\usetheme{Warsaw} %allowframebreaks numbering in the title \\setbeamertemplate{frametitle continuation}{(\\insertcontinuationcount/)} %\\setbeamertemplate{frametitle continuation}{(\\insertcontinuationcount/\\inserttotalcontinuationcount)} \\title{title} \\author{author} %%%%% \\begin{document} \\begin{frame}[allowframebreaks]{allowframebreaks title} frame 1 \\framebreak frame 2 \\framebreak frame 3 \\framebreak \\end{frame} \\end{document}", "How to encrypt a file or directory in Linux? What's the most popular command to do such things as encrypting a file or directory in terminal in Linux?", "Applications Don't Show Up in Spotlight Spotlight has stopped showing any results for my Applications. I've tried reindexing and removing the index so it rebuilds it. No change. I've tried adding Applications to the Privacy tab and removing it, no change. I tried repairing disk permissions and redoing the above, no change. I've tried removing everything from the index except Applications and then I just get nothing for any search at all (except dictionary entries). I tried adding a symlink in my homedir to Applications and reindexing, but no change. Any ideas on what to do? I'm running Snow Leopard. This is driving me crazy! Update: I've noticed that when I start a reindex with sudo mdutil -E / and then immediately do a Spotlight search for an app that the app shows up temporarily until Spotlight gets disabled due to active indexing. After the indexing is done, the app entries go away.", "Classification of automorphisms of projective space", "When is $(p - 1)! + 1$ a power of $p$? A friend asked me this question: If $p$ is a prime, prove that $(p - 1)! + 1$ is a power of $p$ if and only if $p = 2, 3$ or $5$. Clearly one direction is obvious, namely that $p=2,3,5$ implies $(p - 1)! + 1$ is a power of $p$. The other direction is not clear to me. Since by Wilson's theorem $p$ divides $(p - 1)! + 1$ so we need to show that if there are no other prime factors then $p=2,3,5$. Can someone give me a hint for establishing this? Thanks", "All of a sudden, Safari on my Mac has started misbehaving. I can't select the text in the address bar, and so I can't go to any new websites. When it redraws, it goes all weird: I've tried deleting the cache, clearing all cookies, disabling all plugins and rebooting. These things didn't help. I've had to switch to Chrome for the time being. Can anyone suggest some other possible remedies?", "How to disprove this fallacy that derivatives of $x^2$ and $x+x+x+\\dots\\quad(x\\text{ times})$ are not same. Possible Duplicate: \\begin{align*} x^2 &amp;= \\underbrace{x + x + x + \\dots + x}_{x \\text{ times}}, \\\\ \\therefore \\frac{\\mathrm{d}}{\\mathrm{d}x} (x^2) &amp;= \\frac{\\mathrm{d}}{\\mathrm{d}x} (\\underbrace{x + x + x + \\dots + x}_{x \\text{ times}}) \\\\ &amp;= \\underbrace{1 + 1 + 1 + \\dots + 1}_{x \\text{ times}} \\\\ &amp;= x. \\end{align*} But we know that $$ \\frac{\\mathrm{d}}{\\mathrm{d}x} (x^2) = 2x. $$ So what is the problem? My take is that we cannot differentiate both sides because $\\underbrace{{x+x+x+\\cdots+x}}_{x \\text{ times}}$ is not fixed and thus $1$ is not equal to $2$.", "tags of mundanity that are gratuitously applied to posts It's an additional unnecessary burden to the honest stacker during suggested edit duty. A question presents some code then the minor editor adds a tag like 'for-loop' or 'forms'. These tags are so general that they only have a handful of followers. They serve no useful purpose and are the cause of many too minor edits. Why not permit culling of generic tags?", "heat weighting: failed to find solution for one or more bones", "How does one prove that if $n \\mid (a^{n}-b^{n}) \\ \\Longrightarrow$ $ \\displaystyle n \\mid \\frac{a^{n}-b^{n}}{a-b}$ where $a,b, n \\in \\mathbb{N}$. What i thought of is to consider $$(a-b)^{n} \\equiv a^{n} + (-1)^{n}b^{n} \\ (\\text{mod} \\ n)$$ and if we suppose that $n$ is odd then we have, $$(a-b)^{n} \\equiv a^{n} -b^{n} \\ (\\text{mod} \\ n)$$ and since $n \\mid (a^{n} - b^{n})$ we have $$(a-b)^{n} \\equiv 0 \\ (\\text{mod} \\ n) $$ I think i am far away from the conclusion of the problem, but this is what i could work on regarding the problem.", "How do I reset my main keychain and completely delete the old one? I changed my password and its been coming up with all of these popups asking for my new password when I first login. If anyone can help with updating my keychain I would appreciate it or you can just help me completely delete and reset it.", "How to vertically center a \"div\" element for all browsers using CSS?" ]

[ "Compiler warning: null reference exception I have the following code in Visual Studio 2005. Dim OutFile As System.IO.StreamWriter Try OutFile = New System.IO.StreamWriter(Filename) // Do stuff with OutFile Catch Ex As Exception // Handle Exception Finally If OutFile IsNot Nothing Then OutFile.Close() End Try But VS2005 brings up the warning for the line \"If OutFile IsNot..\" that Variable 'OutFile' is used before it has been assigned a value. A null reference exception could result at runtime. Is there some way of removing this warning by subtly altering the code or is there just a better way of doing what I'm trying to do? Thanks Rob", "Earlier today, I was suspended from chat due to an inappropriate message (I totally deserved it, but that's not the point). I looked at my phone, and this is all that it told me: ...which confused me because chat was still moving as normal. I didn't realize that I had been suspended until I checked on my computer to see what the heck was going on. To me, \"This room is read-only\" sounds like some sort of database lockup or something related specifically to the room, not the user. It doesn't give any feedback to indicate that the room will be \"read-only\" for 30 minutes, and doesn't mention that all other rooms are also \"read-only\". Even a message saying just \"You have been suspended from chat\" would be more helpful.", "Making pen and ink corrections on a UK visa form?", "Something's been bugging me about SO for a while now, that is the inaccuracy of \"length of time\" strings. The best example I can give at the moment is . If you look at the length of time he's been registered, it says 1 year. He joined the site September 2008, which is only 3 months off two years. It's the same with answers - you can give an answer 50 seconds before anyone else, but at certain times page views will show both as \"5 minutes ago\" or whatever. That's not quite as bad, but with answers being sorted \"randomly by votes\" by default you could lose out on votes or being marked as the correct answer to the slower answer even if they're both the same. There's probably a better method amongst these, IMO: \"Vulgar fraction\" unicode characters Member for 1½ years answered 5¼ minutes ago asked 3⅓ hours ago Different units Member for 21 months (at least it's better than \"1 year\") Answered 306 seconds ago (ugly, I know) Asked 64 minutes ago (also ugly) Combining units Member for 1 year 9 months (fits easily on the profile screen) Answered 5 minutes 6 seconds ago (probably too long) Asked 3 hours 20 minutes ago (also long) Rounding up I personally prefer option 1, unicode fraction characters. \"Member for 21 months\" is pretty good too because it's easy to quickly work out. \"Asked 452 seconds\" ago is horrible though. EDIT: I'm completely aware of the timestamp hover because I am forced into using it so much. It's a great feature, but it's not really in your face so not everyone knows about it. I still think there's a better \"glancing\" solution than having to hover over the time string.", "Rigorously proving equal tension on both ends There is always one point in introductory mechanics that has been continuously bothering me ever since I had taken my freshman physics course - Why does a massless rope have its tension equal on both ends? I have been searching for a good explanation on various textbooks at different levels, but none of them provided me a satisfactory explanation. They either State directly \"we assume the string is massless and the pulley has no friction, therefore the tension must be the same throughout the string\" without further any elaboration and continue the calculation, Claim without any reasons that \"whenever the rope and the pulley are massless and frictionless, the tension will be the same on both sides\", or Explain using a lot of hand-waving arguments regarding infinite acceleration, non-zero moment of inertia, etc. , in one line or two. Although those hand-waving arguments of type $(3)$ do sound quite reasonable to me and will convince me for a while every time I review them. But after a while, I will start feeling not well about this whole tension concept again. Therefore, I am looking for a rigorous (in the physicist's sense) proof of exactly why and when do the tension in rope will be uniform, and hopefully from that I can clean up all of my conceptual difficulties.", "How can I get this 'Version: 0.1.0 - 94\" value from the tag in selenium webdriver? How can I get this Version: 0.1.0 - 94 value from the &lt;div&gt; tag in selenium webdriver? and here is my code: &lt;div _ngcontent-qbk-c3=\"\" style=\"text-align: center;\"&gt;Version: 0.1.0 - 94&lt;/div&gt;", "Buying from Play store using a credit card with foreign billing address Is it possible to use a credit card with a foreign billing address to buy items from a local Play store? I have a Visa credit card from a German bank with a billing address in Germany registered in my Google Wallet. I have successfully used my Wallet to pay for online purchases from several online service providers in different foreign currencies so I am sure the credit card is correctly registered in my Wallet account. However, while physically located in the UK, I cannot complete any purchase from the UK Play store. At the point when I need to select my preferred payment method from my Wallet account, it shows my registered credit card greyed out with the text \"Unsupported Payment method\" next to it.", "How do I eliminate reflection on glass? When I take a picture through a window, I often see a reflection on the glass. I have noticed that this occurs mostly when it is dark or overcast outside or it is especially bright on my side of the glass. How can I stop this?", "YA book about a young powerful female caster attending a school that trains in magical arts and duels I read a young adult novel around the turn of the century. This story features a young female protagonist that is very naturally gifted in magic. She is attending a to learn mastery and control over her gifts. A lot of her school revolves around magic dueling. The participants are taught to extend their inner aura like a second magical skin, possibly referred to as creating a shield, or . The user can increase the strength of the shield by focusing harder on it, but doing so means you have less ability to be offensive. The amount of energy needed to create a shield was half the energy a foe would need to focus at you to break it. Ex: Mage A and B are equally matched. Mage A focuses half his power into a shield. Mage B would then need to focus 100% of his power to break A’s shield. Another aspect I remember is that when dueling, a school master would extend a personal shield on to one of the combatants as a sort of secondary shield that goes underneath the combatants. When one mage broke the others mages personal shield, the school masters shield protects the losers life from harm, and the breaker of the shield is declared the winner. I distinctly remember one match in which the protagonist is having a duel with another strong student. She creates a wind storm around herself that picks up the sand from the arena floor and makes her impossible to see and thus makes it hard for her opponent to focus on her shield to break it. She then lashes out at her opponent with incredibly powerful strikes with the final strike being so hard it shatters the opponents shield and then breaks the school masters shield as well and stops just shy of killing her dueling partner. Any assistance on this one? I think my daughter would love to read it.", "Mass Uninstalling Just been working on a new laptop today (Acer) and it was pre-installed with all sorts of crapware. Mostly games and \"backup utilities\" and McAfee. I had to manually uninstall about 30 apps via Vista's Programs and Features So it got me wondering is there any way of mass uninstalling or queuing an app to be uninstalled? Through Vista/XP you need to wait for Install Shield or whatever to close before beginning to uninstall the next app. Took way more time than it should have. Just another one of those Windows annoyances! Any help appreciated as I often need to do this when I come across a slow machine that's just been clogged with a bunch of useless apps", "How can I run Maniac Mansion through ScummVM? Day of the Tentacle Remastered Edition includes Maniac Mansion as a . The game appears to be exactly the same as the old DOS release (albeit, the enhanced version). If possible, how can I run this game through ScummVM? Pointing ScummVM at my installed game doesn't work. What do I need to do to play this version of Maniac Mansion?", "Recent movie involving dimensions and time travel/displacement It's a (relatively) recent movie about a kid whose scientist father is missing or presumed dead. The kid experiences strange situations (e.g., books from a case fall off). In the end, it was the father the one that was throwing those books to draw the attention of the kid. Does anyone know the name of this film?", "May I use Google Fonts for creating a logo with commercial purposes? I want to create a logo for a contest, the winner will be paid and the winning logo will be the institutional logo of an academic entity, so I need a font which can be used freely or at a cheap cost for commercial purposes. I see that Google Fonts are delivered as \"free fonts\" for websites: May I use them freely for graphic design products (a logo in particular) as well?", "How to trigger a warning when a certain function is called (not compiled)?", "It's possible to do a array of Matrix in Matlab?", "Google Chrome: Version 32.0.1700.107 m This happens when displaying the profile and clicking on the number of visited days/consecutive. .", "How to disable \"time travel\" entirely? Every time I open a question I get this oh so funny 90s feel with scrollers and whatnots. In every question I need to click it off. The button seems to only work for the specific page I load; loading a different page shows the theme again. Is this an attempt to keep people from using the site for a few days or how do I tell you \"please never ever do anything like this if you want me to keep contributing here\"? Yes I have no sense of humor if this is an attempt at that. How do I turn off \"time travel\" (also known as \"back to the future\") mode off permanently, on all questions, and preferably network-wide?", "How to check who owns the Slack's workspace? I'd like to check who owns (or at least some kind of public profile page) some workspace based on its subdomain (e.g. xyz.slack.com). Is it possible?", "This is a about how to handle email sent from your server being misclassified as spam. For additional information you may find these similar questions helpful: Sometimes I want to send newsletters to my customers. The problem is, that some of the emails get caught as spam messages. Mostly by Outlook at the client (even in my own Outlook 2007). Now I want to know what should be done to create \"good\" emails. I know about reverse lookup etc., but (for example), what about a unsubscribe link with an unique ID? Does that increase a spam rating?", "How are constraint forces represented in Lagrangian mechanics?" ]

[ "I recently got my Blacksmithing skill to 100. Now in the skills menu I can press space to make it Legendary, which will put it back to a skill level of 15 and reset my perks. I am wondering: What benefit is there from making a skill Legendary apart from being able to level up the skill more thus having infinite levels?", "After trying to delete apache and tomcat, and now trying to reinstall apache 2, I am missing the init.d/apache2 file to start/stop my server. I am not sure if the new install actualy worked, and my apt-get purge apache2 didn't remove everything in the first place! How can I get the init.d/apache2 file to test if server starts / is installed properly (I had removed files and directories manually)?", "Always return data from last week's Monday thru Sunday", "I am trying to set multiple definition queries for one layer based on one field using python. ie. I have a City layer with a field that holds the city name. I want a copy of the layer in an MXD with the Definition query set for each value in the City field. So essentially, I have one source layer, with a copy of the layer as many times as there are values in the City field. The query would look like this: CITY = 'Atlanta'", "How do I remove/delete a folder that is not empty?", "Determine the number of functions $f: \\{1,2,3....,1999\\}\\to \\{2000,2001,2002,2003\\}$satisfying the condition that $f(1)+f(2)+...f(1999)$ is odd. Problems:Determine the number of functions $$f: \\{1,2,3....,1999\\}\\to \\{2000,2001,2002,2003\\}$$ satisfying the condition that $f(1)+f(2)+...f(1999)$ is odd. My Attempt: Each integer in domain has $4$ choices and therefore the total number of functions is $f$ is $4^{1999}.$ Since there are an equal number of functions that yield odd or even result, we can directly write that the number of functions satisfying the above condition to be $2*4^{1998}.$ I am unsure about this last claim and would like to prove it (if it is true.)Also is the answer to this problem correct? Edit $1$: I tried to proceed further in the following manner: For a given mapping $f$ let the number of integers assigned to $2000,2001,2002$ amd $2003$ be $p,q,r$ and $s$ respectively, where $p,q,r,s\\in \\mathbb{Z}^+$. Therefore the sum in question can be written as $f(1)+f(2)+...+f(1999)=2000p+2001q+2002r+2003s.$ Clearly the sum will be odd iff $q+s$ is odd. Also note that $p+q+r+s=1999\\Rightarrow p+r$ is even. On the other hand if we let $q+s$ as even then $p+r$ must be even. Now the number of values of $p,q,r$ and $s$ for which the above two lemmas hold is the same and therefore if we let $f$ to be the function which maps elements form $\\{1,2,3,...,1999\\}$ to $\\{2000,2001,2002,2003\\}$ such that $q+s$ is even and $g$ to be the function hich maps elements form $\\{1,2,3,...,1999\\}$ to $\\{2000,2001,2002,2003\\}$ such that $p+q$ is even we will get a bijection.(Maybe!)", "Simple explanation to the induction from the slowly changing $\\vec B$ of a solenoid in the region of $0$ magnetic field", "How to dynamically create a local variable?", "Let $f: \\mathbb R^2 \\to \\mathbb R$ defined as $f(x,y)=(x^2+y^2)\\sin(\\dfrac{1}{\\sqrt{x^2+y^2}})$ if $(x,y) \\neq (0,0)$, $f(x,y)=(0,0)$ if $(x,y)=(0,0)$ Prove that $f$ is differentiable at $(0,0)$ but that the partial derivatives of $f$ are not continuous at the origin. The attempt at a solution: I had some problems at the first part of the exercise: I've calculated $\\dfrac{\\partial f}{\\partial x}(0,0)$ and $\\dfrac{\\partial f}{\\partial y}(0,0)$, both exist and are equal to $1$. So, to prove $f$ is differentiable at the origin, I have to show that $\\lim_{(x,y) \\to (0,0)} \\dfrac{|f(x,y)-(f(0,0)+&lt;\\nabla f(0,0),(x,y)&gt;)|}{\\|(x,y)\\|}=0$ But $\\lim_{(x,y) \\to (0,0)} \\dfrac{|f(x,y)-(f(0,0)+&lt;\\nabla f(0,0),(x,y)&gt;)|}{\\|(x,y)\\|}$ equals $\\lim_{(x,y) \\to (0,0)} \\dfrac{|(x^2+y^2)\\sin(\\dfrac{1}{\\sqrt{x^2+y^2}})-(x+y)|}{\\|(x,y)\\|}$. I don't know how to show this limit equals $0$. For the second part (I've only analyzed $\\dfrac{\\partial f}{\\partial x}$ since both cases are the same), what I did was try to show that $\\lim_{(x,y) \\to (0,0)} \\dfrac{\\partial f}{\\partial x}(x,y) \\neq \\dfrac{\\partial f}{\\partial x}(0,0)$ I thought of considering the curve $\\phi(t)=(t,0)$, so $\\lim_{t \\to 0} (f\\circ \\phi)(t)=\\lim_{t \\to 0} 2t\\sin(|t|^{-1})-\\dfrac{t\\cos(|t|^{-1})}{|t|^{-1}}$. But $\\lim_{t \\to 0^{+}} \\dfrac{t\\cos(|t|^{-1})}{|t|^{-1}}=\\lim_{t \\to 0^{+}} \\cos(\\dfrac{1}{t})$ and this limit doesn't exist, so the original limit doesn't exist. This shows the partial derivative with respect to $x$ at the point $(0,0)$ is not continuous. I would appreciate if someone could help me to finish the first part and tell me if what I did in the second part of the problem is correct.", "com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure", "I read this book once when I was in middle school. A girl solves a murder or a mystery on a spaceship. It was a thin paperback books. All I can remember is that there was an alien, and there was a movie star or actress or famous makeup artist on the ship traveling with another woman. By the end of the book the murderer was the woman the actress was traveling with who forced her to use her makeup skills to disguise her, and she was really some kind of alien.", "If you give a user sudo privileges how can I remove the sudo privileges and make the user become just a regular user? I used: sudo adduser username sudo Now I've changed my mind.", "How to avoid bad box with long words with no hyphenation?", "I wanted to leave the question title as is so as not to take away from my amusement :). Anyway, It's raining. What is raining? Is it the sky? The clouds? The weather? The rain? What is \"it\"? Any historical insights on the statement?", "Can Spirit Guardians affect enemies through walls?", "What's the canonical way to check for type in Python?", "What are these circular splotches on my negatives?", "Is this mold? Black? White? Guys I need to find out what this is- it's also on my wooden bed racks", "Are there any method to extend a filesystem when i adding more hdd to it without using LVM? What are those ?", "How unique is the php session id" ]

[ "How do we know an $ \\aleph_1 $ exists at all? I have two questions, actually. The first is as the title says: how do we know there exists an infinite cardinal such that there exists no other cardinals between it and $ \\aleph_0 $? (We would have to assume or derive the existence of such an object before we label it something like $ \\aleph_1 $.) My second question is, can we say for certain if there's any limit to the number of cardinals existing between $ \\aleph_0 $ and continuum (i.e. $ 2^{\\aleph_0} $)? I mean, how could we know that there&#39;s not an infinite number of cardinals between the two - perhaps even more than $ \\aleph_0 $?", "Why do you lose reputation for downvoting answers?", "what is the area of the region [ (x,y):0<x , y<1 , 3/4<x+y<3/2 ]?", "Question of an isomorphism of $\\epsilon_ 0$ and a subset of the rationals.", "I am not able to sum all the opportunities under the account ? How will I do that? What I have to use in this to run the trigger? Is it possible to create because opp. is child and account is parent ? trigger sumAllopptyAmtAccount on Account(before insert) { Set &lt; ID &gt; AccID = New Set &lt; ID &gt; (); if (Trigger.isInsert) for (Account oppAc: trigger.New) { AccID.add(oppAc.AccountID); } List &lt; Account &gt; acc = [select id, SumAll_Opprty__c from Account where id in: a.AccID]; List &lt; Opportunity &gt; opp = [selece id from Opportunity where AccountID in: a.AccID]; for (Account a: acc) { a.SumAll_Opprty__c = con.size(); } }", "How to specify font size less than 10pt (or more than 12pt)?", "I seem to have screwed up something that allows you to inset evenly, I think I have tried every combination of settings in inset and pivot center and even is far from even. I tried uninstalling and re installing blender 2.71 and get the same result. The image attached is a simple default cube that I tried to inset evenly. I have also attached the blend file link help??", "Identical creatures entering the battlefield", "Start script on open blender file", "How to change an application icon programmatically in Android?", "Does 'but for' mean: 'If we had X (but we didn't), Y would have been the consequence'? Or can it also mean; because we had X, as a result Y happened? Some different examples of but for: (Case 1) But for a cup coffee, it was to be a productive day of writing. Unfortunately, I'd run out, and spent the day craving. (Case 2) But for the glass of wine I had dinner, the house work didn't get done. (Case 3) But for the glass of wine I had for dinner, I would have got the house work done What is the correct usage of \"but for\"?", "Proving a function is Lipschitz continuous Show that the following function is Lipschitz continuous and find a Lipschitz constant $$y\\mapsto f(x,y)\\\\ f(x,y)=\\frac{y}{x}\\ln(\\frac{y}{x})\\text{ , } |x-1|\\leq\\frac{1}{2}\\text{ , } |y-e|\\leq\\frac{e}{2} $$ I have no clue on where to begin to prove this. My first question is how I should interpret this function, is $x$ a sort of constant?", "How can I limit ssh *remote* port forwarding? I need to limit which ports can be remotely 'ssh -R' forwarded by an user. I know about permitopen option on authorized_keys, but as it says on man page it only limits local 'ssh -L' port forwarding As discussed a user would get the same with netcat or similar, but in this case user has no shell access I also found that talks about using selinux or LD_PRELOAD, but I never configured selinux before and can't find info on how to do that with LD_PRELOAD. maybe someone have made a patch for openssh to implement that? EDIT: I've found so I guess it's not yet implemented", "After considering the answers to my previous question (), I've decided to take the 4 or so repositories I have and consolidate them into one. This of course leads to the question, what's the best way to do this? Is there a way to combine two or more repositories maintaining the version history for both? Edit: I should also point out that I'm using Assembla.com, which does not provide access to the svnadmin command, AFAIK Another edit: Does this even matter? If svnadmin works on URLs, then it's no problem then.", "derivative under integral intuition", "Is it true that a language is regular? Is it true that for every regular language $L \\subseteq \\{0,1\\}^*$, language $\\big\\{ w^{|w|} \\big| w \\in L \\big\\}$ is regular? I don't know how to prove that.Could you give me a hint? Thank you", "Destroy chunked block like Minecraft", "Another phrase for \"a chicken and egg situation\" Is there any other phrase that conveys the same meaning as the phrase \"a chicken and egg situation\" especially if one has to use this phrase in an official/corporate set up?", "What are some alternatives to \"hover\" on touch-based devices? Came up recently in a 37signals podcast: The straightforward, \"brute-force\" solution is to just use the first touch on a UI object as the hover. It works. But are there other, more elegant solutions? For instance, could the hardware ever be made to support actual finger hovering?", "Always sort Recent Places by date modifed" ]

[ "Why do I have to enter my password to log in? Using the Stack Exchange login, why do I have to enter my password again and again to log in? Wasn’t the whole purpose of OpenID to do away with this? This doesn’t even only happen when visiting a new Stack Exchange site – it also happens for sites where I already have an account but which I don’t visit regularly. Here’s what I mean: Of course I don’t remember my password (it’s a long random string). And so I have to go to my password manager and manually copy the password from openid.stackexchange.com’s account into the login form. – And incidentally, this is what my password manager looks like now: (And, by the way, those are the only entries in my keychain so far, but by far not the only SE sites where I have an account.) … I feel that this defeats the purpose of site-wide login and OpenID. In the olden times when MyOpenID was still working properly, I’d simply enter my OpenID on the login form, and the software would take care of the rest – namely, redirect to the OpenID service, (automatically) verify that I was authorised to use it, and redirect back to the original website, having logged me in. It was literally one button click for me. It’s substantially more work now, and I’d like to understand why this regression is necessary. (Note: of course once a site’s password has landed in my password manager I (probably?) won’t have to enter it again. But still: wasn’t site-wide login and OpenID supposed to solve this already?)", "I'm new to d20. I recently acquired a bunch of D&amp;D books and I'm sure they are all either 3.0 or 3.5, but it doesn't say in the book which version it is. How can I tell which version the book is? For instance, I have \"Complete Warrior - A Player's Guide to Combat for All Classes\". It's hard back, published in '03. Is it 3.0 or 3.5? Another example, I have \"Sword and Fist - A Guidebook to Fighters and Monks\". Perfect Bound, published in '01. Is it 3.0 or 3.5?", "Is PCA unstable under multicollinearity? I know that in a regression situation, if you have a set of highly correlated variables this is usually \"bad\" because of the instability in the estimated coefficients (variance goes toward infinity as determinant goes towards zero). My question is whether this \"badness\" persists in a PCA situation. Do the coefficients/loadings/weights/eigenvectors for any particular PC become unstable/arbitrary/non-unique as the covariance matrix becomes singular? I am particularly interested in the case where only the first principal component is retained, and all others are dismissed as \"noise\" or \"something else\" or \"unimportant\". I don't think that it does, because you will just be left with a few principal components which have zero, or close to zero variance. Easy to see this isn't the case in the simple extreme case with 2 variables - suppose they are perfectly correlated. Then the first PC will be the exact linear relationship, and the second PC will be perpindicular to the first PC, with all PC values equal to zero for all observations (i.e. zero variance). Wondering if its more general.", "Size of files in Windows OS. (It's KB or kB?) One \"kilobyte\" (KB) is 1024 bytes in JEDEC-standard, whereas the definition has shifted, in most contexts, to mean 1000 bytes (kB) in accordance with SI. To resolve this difference, binary prefixes (kiB) are used. So we have 3 choices for using prefixes - JEDEC, IEC (both in Binary), and Metric (in Decimal). My questions are- What prefix standard does Windows use in showing the file size? (surely it's not IEC standard) Why does Windows OS show sizes of files in KB (using a capital alphabet \"K\") when it's a small alphabet \"k\" for a Kilo in SI units? A capital \"K\" represents Kelvin in SI system of units. Am I missing something here in understanding?", "I built a ZI model and it is producing predicted values that are from a very small range when compared to the observed values. Plus it does not produce any zeros. See the fitted vs. observed graph below. My model structure is given below. My response is a count variable and the predictor is continuous water level measurements (scaled). m.u.meanwl.gu &lt;- zeroinfl(GU ~ MeanWLScaled | MeanWLScaled, data = uluabat_wl_fg, dist = \"negbin\", link = \"logit\") I need help to figure out what's wrong and fix it. Thanks in advance.", "Security Review - CRUD/FLS Checks for every SOQL Query I know this sounds like a standard question, so please bear with me. Recently our Security Reviews fail due to CRUD/FLS violations. The highlighted codelines include almost every SOQL Query in the application. Our approach is usually as follows: In case of displaying data on VF pages we either use sObjects fields or use the platform methods to check the accessibility of the fields In case of domain logic triggered by the user (e.g. by clicking a button on a VF page) we have a helper class that checks every field to be updated before doing the DML operation. Up until recently this approach has worked fine (and passed pervious Security Reviews). As mentioned above the latest Security Review results seem to require us to check every field in a SOQL query for accessibility even if it is never displayed back to the user. Let's suppose the following program flow as an example: Query an object with some fields Perform some modification on said fields Perform an update on the sObject to save the modification using a helper class which checks for the required CUD/FLS rights for the modified fields As I see it there is no need for checking field accessibility in step 1 in that case (since nothing is displayed back to the user and the dml operation is already protected). Is that correct or am I missing something? So is it really required to do an accessibility check for every SOQL Query in the code? Another question would be how to handle background operations in that case like data purging. These have either to be running in system mode (which causes issues during the Security Review) or require the job to be started by a user with the appropriate access rights (which can be error prone and is not that user friendly). Is there any best practice regarding that. Unfortunately I could not find a question targeting exactly that issue. Most of the questions I have found are related to how to perform that check (like or ). So please apologize in case the question was already answered (I would really appreciate a link to the answer then). Thanks for your time and help. Mathias", "It appears that in PHP objects are passed by reference. Even assignment operators do not appear to be creating a copy of the Object. Here's a simple, contrived proof: &lt;?php class A { public $b; } function set_b($obj) { $obj-&gt;b = \"after\"; } $a = new A(); $a-&gt;b = \"before\"; $c = $a; //i would especially expect this to create a copy. set_b($a); print $a-&gt;b; //i would expect this to show 'before' print $c-&gt;b; //i would ESPECIALLY expect this to show 'before' ?&gt; In both print cases I am getting 'after' So, how do I pass $a to set_b() by value, not by reference?", "Does a four-divergence extra term in a Lagrangian density matter to the field equations? Greiner in his book \"Field Quantization\" page 173, eq.(7.11) did this calculation: ${\\mathcal L}^\\prime=-\\frac{1}{2}\\partial_\\mu A_\\nu\\partial^\\mu A^\\nu+\\frac{1}{2}\\partial_\\mu A_\\nu\\partial^\\nu A^\\mu-\\frac{1}{2}\\partial_\\mu A^\\mu\\partial_\\nu A^\\nu $ $\\space\\space\\space\\space=-\\frac{1}{2}\\partial_\\mu A_\\nu\\partial^\\mu A^\\nu+\\frac{1}{2}\\partial_\\mu[A_\\nu(\\partial^\\nu A^\\mu)-(\\partial_\\nu A^\\nu) A^\\mu]$ The last term is a four-divergence which has no influence on the field equations. Thus the dynamics of the electromagnetic field (in the Lorentz gauge) can be described by the simple Lagrangian ${\\mathcal L}^{\\prime\\prime}=-\\frac{1}{2}\\partial_\\mu A_\\nu\\partial^\\mu A^\\nu$ Yes, if it is a four-divergence of a vector whose 0-component doesn't contain time derivatives of the field, indeed according to the variational principle this four-divergence will not influence the field equation. And actually I calculated the time-derivative dependence of 0-component of $[A_\\nu(\\partial^\\nu A^\\mu)-(\\partial_\\nu A^\\nu) A^\\mu]$, in which only $[A_0(\\partial^0 A^0)-(\\partial_0 A^0) A^0]$ could possibly contain time-derivative, which vanishes fortunately, so whatever the general case it doesn't matter in this present case. But how can he seem to claim that it holds for a general four-divergence term,The last term is a four-divergence which has no influence on the field equations? EDIT: I only assumed the boundary condition to be $A^\\mu=0$ at spatial infinity, not at time infinity. And the variation of the action $S = \\int_{t_1}^{t_2}L \\, dt$ is due to the variation of fields which vanish at time, $\\delta A^\\mu(\\mathbf x,t_1)=\\delta A^\\mu(\\mathbf x,t_2)=0$, not having the knowledge of $\\delta \\dot A^\\mu(\\mathbf x,t_1)$ and $\\delta \\dot A^\\mu(\\mathbf x,t_2)$, which don't vanish generally, so the four-divergence term will in general contribute to the action, $$\\delta S_j=\\delta \\int_{t_1}^{t_2}dt\\int d^3\\mathbf x \\partial_\\mu j(A(x),\\nabla A(x),\\dot A(x))^\\mu =\\delta \\int_{t_1}^{t_2}dt\\int d^3\\mathbf x \\dot j^0 =\\int d^3\\mathbf x [\\delta j(\\mathbf x, t_2)^0-\\delta j(\\mathbf x, t_1)^0]$$ which does not vanish in general!", "$Q_8$ is isomorphic to a subgroup of $S_8$, but not isomorphic to a subgroup of $S_n$ for $n\\leq 7$. Question is to prove that : $Q_8$ is isomorphic to a subgroup of $S_8$, but not isomorphic to a subgroup of $S_n$ for $n\\leq 7$. I see that $Q_8$ is isomorphic to subgroup of $S_8$ by left multiplication action. Hint given was to prove that stabilizer of any point contains $\\{\\pm 1\\}$. To prove Cayley's theorem, stating any group is isomorphic to a subgroup of $S_n$ we take action of given group on a set $A$ having same cardinality. with that motivation I want to check if there is a Isomorphism then there is a map from $G\\times A \\rightarrow A$. i.e., $G$ gives a permutation group $S_A$. I tried in same manner. Suppose $Q_8$ is isomorphic to subgroup of $S_n$ with $n\\leq 7$ then it should come from a group action of $Q_8$ on a set of cardinality atmost 7. Suppose $Q_8$ acts on a set $A$ with possible cardinality at most 7. $stab(a)=\\{g\\in Q_8 : g.a=g \\forall a\\in A \\}$ $cl(a)=\\{g.a : g\\in Q_8\\}$ I know number of elements in class of $a$ equals to index of stabilizer. As $cl(a)=\\{g.a : g\\in Q_8\\}\\in A$ i.e., $cl(a)\\subseteq A$ and as $|A|\\leq 7$ i see that $|cl(a)|\\leq 7$. But, $|cl(a)|=|Q_8:stab(a)|$ for any element $a\\in A$. So, $|Q_8:stab(a)|=|cl(a)|\\leq 7$ for all $a\\in A$. So, $stab(a)$ should be non trivial subgroup of $Q_8$ if not then $|Q_8:stab(a)|=8$ non trivial subgroup (proper) of $Q_8$ contains $\\{\\pm1\\}$. So, In the worst case, $\\{\\pm 1\\}\\subseteq stab(a)$ for all $a\\in A$. As $Ker(\\eta)=\\cap_{a\\in A}stab(a)$ (where $\\eta$ is the action of $Q_8$ on $A$) we see that $\\{\\pm 1\\}\\subseteq Ket(\\eta)$ which means that $Ker(\\eta)$ is non trivial. thus there is no isomorphism (coming from $\\eta$) between $Q_8$ and any subgroup of $S_7$. I would be thankful if someone can check whether my approach is correct or if there is any other simple possible way. P.S : Usually what i do to see whether two groups are isomorphic or not is to check for cardinality, abelian property, no of elements with same order and so on. But I was having no idea when i fail in all these ways. With this Group actions i could see possibility for getting a precise conclusion on Isomorphisms.I would like to Thank Mr. Jyrki Lahtonen (a user of Math.SE) who made me to get used to Group actions. P.S $2$: If any thing is wrong in my idea, it is entirely my fault, and if anything is correct in this whole credit should go to Mr. Jyrki Lahtonen", "I remember reading it while in middle school in English in the United States, so the latest it would have come out was 1998. I don't remember if it was all one author, or even the same universe. These are the stories I remember: A man finds a way to create a medicine that prevents radiation poisoning (or possibly makes someone fireproof... it's a little confused in my head) and learns that part of the problem is finding a market for it. I vividly remember the inventor telling someone to not \"let the doorknob ream you\" as it slams shut. A bout of graffiti artists leads to the city buying anti-graffiti paint that dissolves any other paint put on top of it. After learning the futility of trying to paint over it, the protagonist consults with a friend and learns that the anti-graffiti paint will eat away at the paint above it at a steady rate, and will even eat successive layers of the anti-graffiti paint. he uses this property to engineer an animation involving a harlequin thumbing this nose at the officials even as they try to wash it away. Some guys (I want to say a gang) go to a clinic for an illegal nanotech transformation. The viewpoint character gets turned into a woman while a friend gets turned into a dog. After roaming about in their new forms, they return to find the clinic being raided, meaning there's no one to turn them back. I think I remember something bad happening to the one transformed into a dog where the transformation continued, erasing his human thought patterns. There was also a scene where the viewpoint character submitted to being sexually assaulted by his former friends as if it was simply to be expected given his form. I don't remember if the first or the second story was the actual first story of the collection... I want to say that those are the order that they showed up as in the book.", "The phrase for when: working in a group to divide responsibility and reduce malicious intent", "What is average distance from center of square to some point?", "ART has better performance and better battery life on paper at least. Should I consider switching to it on my moto g? What are the results I can expect? What precautions should I take? Is it easy to turn back to dalvik?", "How can I make a div not larger than its contents?", "Correct user names when tracking /etc/ in git repository and committing as root We use git to track changes in /etc/ on our servers. Administrators work as root when changing files in /etc/, and thus their commits have author root &lt;root@machinename&gt; This is not very satisfying since you cannot see which admin actually did the change. What can we do to get the real admin names in the git log? I don't think that keeping a local clone of the repository is feasible since we often change interatively until something works, and a change-commit-push-seeError-repeat cycle would not help here.", "How can I remap Caps lock to both Escape and Control?", "Looking for a single word for 'blind worship' Is there a single word for 'blind worship' as in worshiping an actor blindly notwithstanding the bad performance?", "Add and remove update channels in an easy terminal way I know there is a GUI in Ubuntu Software &amp; Updates to enable the update channels updates proposed backports security as shown in this screenshot: I am looking for an easy way to do this from within a terminal using commands such as sudo apt-add-update enable updates sudo apt-add-update enable proposed sudo apt-add-update enable backports sudo apt-add-update enable security sudo apt-add-update disable updates sudo apt-add-update disable proposed sudo apt-add-update disable backports sudo apt-add-update disable security and an additional thing sudo apt-add-update enable default sudo apt-add-update disable default Some examples for a better understanding An empty sources.list cat /etc/apt/sources.list &lt;empty&gt; sudo apt-add-update enable security &lt;empty&gt; One enabled repository (main) cat /etc/apt/sources.list deb http://archive.ubuntu.com/ubuntu wily main sudo apt-add-update enable security deb http://archive.ubuntu.com/ubuntu wily main deb http://archive.ubuntu.com/ubuntu wily-security main Two or more enabled repositories in one or two lines cat /etc/apt/sources.list deb http://archive.ubuntu.com/ubuntu wily main universe or deb http://archive.ubuntu.com/ubuntu wily main deb http://archive.ubuntu.com/ubuntu wily universe sudo apt-add-update enable security deb http://archive.ubuntu.com/ubuntu wily main universe deb http://archive.ubuntu.com/ubuntu wily-security main universe or deb http://archive.ubuntu.com/ubuntu wily main deb http://archive.ubuntu.com/ubuntu wily-security main deb http://archive.ubuntu.com/ubuntu wily universe deb http://archive.ubuntu.com/ubuntu wily-security universe With deb-src entries cat /etc/apt/sources.list deb http://archive.ubuntu.com/ubuntu wily main universe deb-src http://archive.ubuntu.com/ubuntu wily main universe sudo apt-add-update enable security deb http://archive.ubuntu.com/ubuntu wily main universe deb-src http://archive.ubuntu.com/ubuntu wily main universe deb http://archive.ubuntu.com/ubuntu wily-security main universe deb-src http://archive.ubuntu.com/ubuntu wily-security main universe With inactive deb-src entries cat /etc/apt/sources.list deb http://archive.ubuntu.com/ubuntu wily main universe # deb-src http://archive.ubuntu.com/ubuntu wily main universe sudo apt-add-update enable security deb http://archive.ubuntu.com/ubuntu wily main universe # deb-src http://archive.ubuntu.com/ubuntu wily main universe deb http://archive.ubuntu.com/ubuntu wily-security main universe The default thing cat /etc/apt/sources.list deb http://archive.ubuntu.com/ubuntu wily-security universe sudo apt-add-update enable default deb http://archive.ubuntu.com/ubuntu wily universe deb http://archive.ubuntu.com/ubuntu wily-security universe Only one entry and the disable action cat /etc/apt/sources.list deb http://archive.ubuntu.com/ubuntu wily-security universe sudo apt-add-update disable security &lt;empty&gt; Different or the same servers for different or the samerepositories, respect each server cat /etc/apt/sources.list deb http://archive.ubuntu.com/ubuntu wily universe deb http://us.archive.ubuntu.com/ubuntu wily main sudo apt-add-update enable security deb http://archive.ubuntu.com/ubuntu wily universe deb http://us.archive.ubuntu.com/ubuntu wily main deb http://archive.ubuntu.com/ubuntu wily-security universe deb http://us.archive.ubuntu.com/ubuntu wily-security main Different Ubuntu releases for different repositories, respect each release cat /etc/apt/sources.list deb http://archive.ubuntu.com/ubuntu wily main universe deb http://archive.ubuntu.com/ubuntu trusty main sudo apt-add-update enable security deb http://archive.ubuntu.com/ubuntu wily main universe deb http://archive.ubuntu.com/ubuntu trusty main deb http://archive.ubuntu.com/ubuntu wily-security main universe deb http://archive.ubuntu.com/ubuntu trusty-security main PPAs or other package sources (not-Canonical) in the sources.list? Ignore! Don't change the protocols, e.g. https, http, tor, ...", "In general relativity (GR), spacetime is viewed as a differentiable manifold of dimension $D$ with a metric of Lorentzian signature $(-,+,+,...,+)$. My question is why differentiable?", "So far, I know if $p$ is a rational prime, then $(1)$ if $p\\equiv 3\\mod4$, then $p$ is prime in $\\mathbb{Z}[i]$. $(2)$ If $p\\equiv1\\mod4$ then $p=π_1 π_2$ where $π_1 $ and $π_2$ are conjugate, Then $π_1 $ and $π_2$ are primes in $\\mathbb{Z}[i]$. $(3)$ $2=(1+i)(1-i)$, then $(1+i)$and$(1-i)$ are primes in $\\mathbb{Z}[i]$. What's are all the prime elements in Gaussian integers $\\mathbb{Z}[i]$? For example, $-3$ are prime in $\\mathbb{Z}[i]$, but not in the above $3$ cases." ]

[ "Error \"Settings to access printer 'printername' are not valid\" when printing from Windows service", "How many inventions did Fred and George have? Fred and George Weasley are known for their trouble-making and general &quot;solemnly swearing they are up to no good&quot;. Their antics/adventures give something to smile about and show us not all wizards are as serious as Professor McGonagall and Hermione. This gives them a reputation of being less intelligent and indeed they only achieved three OWLs. However, we also see the twins have quite a brilliant side! Being able to open and successfully run a shop in Diagon Alley without having completed their Hogwarts education is no easy take (IMO, anyway). Their creations helped students get out of class, our heroes out of tight spot, and even stop our enemies execute an evil plot. Ginny may have said it best: &quot;We’ve been hearing explosions out of their room for ages, but we never thought they were actually making things,&quot; said Ginny. &quot;We thought they just liked the noise.&quot; Harry Potter and the Goblet of Fire Do we know how many things Fred and George invented?", "$|G|>2$ implies $G$ has non trivial automorphism Well, this is an exercise problem from Herstein which sounds difficult: How does one prove that if $|G|&gt;2$, then $G$ has non-trivial automorphism? The only thing I know which connects a group with its automorphism is the theorem, $$G/Z(G) \\cong \\mathcal{I}(G)$$ where $\\mathcal{I}(G)$ denotes the Inner- Automorphism group of $G$. So for a group with $Z(G)=(e)$, we can conclude that it has a non-trivial automorphism, but what about groups with center?", "Defining scalable \"white curly brackets\" {| and |} (⦃ and ⦄) I would like to construct what Unicode calls \"white curly brackets\" that are in addition scalable. They look like ⦃ (≈{|) and ⦄ (≈|}) and have Unicode codepoints U+2983 and U+2984. unicode-math has them as \\lBrace and \\rBrace, but (1) I don't presently use XeTeX or LuaTeX and (2) their design (shown in on pages 3-4) is not to my liking: the brace part is too fat for my taste, and I would like the vertical bar to not leave any protrusions. I am trying to have them visually match the parentheses \\llparenthesis, \\rrparenthesis, \\llbracket, and \\rrbracket from stmaryrd. Right now I am using a makeshift definition, which is sufficient for now, but the symbols don't scale (in general or with \\left/\\right). Here is sample code: \\documentclass{article} \\usepackage{amsmath} \\usepackage[only,llbracket,rrbracket,llparenthesis,rrparenthesis]{stmaryrd} % for comparison with 4 similar parenthesis symbols \\usepackage{accsupp} % for ensuring the right Unicode codepoint upon pasting \\newcommand*{\\llbrace}{% \\BeginAccSupp{method=hex,unicode,ActualText=2983}% \\textnormal{\\usefont{OMS}{lmr}{m}{n}\\char102}% \\mathchoice{\\mkern-4.05mu}{\\mkern-4.05mu}{\\mkern-4.3mu}{\\mkern-4.8mu}% \\textnormal{\\usefont{OMS}{lmr}{m}{n}\\char106}% \\EndAccSupp{}% } \\newcommand*{\\rrbrace}{% \\BeginAccSupp{method=hex,unicode,ActualText=2984}% \\textnormal{\\usefont{OMS}{lmr}{m}{n}\\char106}% \\mathchoice{\\mkern-4.05mu}{\\mkern-4.05mu}{\\mkern-4.3mu}{\\mkern-4.8mu}% \\textnormal{\\usefont{OMS}{lmr}{m}{n}\\char103}% \\EndAccSupp{}% } \\begin{document} \\noindent ok: \\(\\displaystyle\\llbrace abc \\rrbrace\\) \\(\\textstyle\\llbrace abc \\rrbrace\\) \\(\\scriptstyle\\llbrace abc \\rrbrace\\) \\(\\scriptscriptstyle\\llbrace abc \\rrbrace\\) \\noindent ok: \\(\\displaystyle \\llbrace \\frac{a}{b} \\rrbrace\\) \\(\\textstyle\\llbrace \\frac{a}{b} \\rrbrace\\) \\(\\scriptstyle\\llbrace \\frac{a}{b} \\rrbrace\\) \\(\\scriptscriptstyle\\llbrace \\frac{a}{b} \\rrbrace\\) \\noindent incorrectly scaled (\\verb|\\scriptsize|): {\\scriptsize\\(\\llbrace abc \\rrbrace\\)} (large magnification required) \\noindent incorrectly scaled (\\verb|\\tiny|): {\\tiny\\(\\llbrace abc \\rrbrace\\)} \\noindent \\verb|\\left| and \\verb|\\right| not possible before \\verb|\\llbrace| and \\verb|\\rrbrace|: \\\\ \\indent \\(\\llbrace \\left\\llbracket\\left\\{\\left[(a) \\cdot bc^{2^3}\\right]^4\\right\\}^5\\right\\rrbracket \\rrbrace\\) % Note: This is also not possible with \\llparenthesis and \\rrparenthesis from stmaryrd. \\noindent for comparison: \\(\\llparenthesis x \\rrparenthesis, \\llbracket x \\rrbracket, \\llbrace x \\rrbrace; (x), [x], \\{x\\}\\) \\end{document} Lines 1 and 2 look just right with the present setup. Lines 3 and 4 demonstrate that my definitions don't scale. Lines 5a/b gives an example of where I would like to be able to use \\left and \\right. Line 6 juxtaposes different types of parentheses for visual comparison. Is there an easy way to scale the glyphs I have constructed myself? Or is designing new glyphs the only way? While the vertical part of my glyphs doesn't leave any protrusions, the \"brace part being too fat\" part of my problem isn't being addressed by my code. With this in mind: I recognize that it might not be that easy to make the brace part of the glyph thinner (though if you can, more power to you), but I think that any solution that addresses the scaling problem for any manually constructed glyph cluster will be a valuable contribution to the community. For a slightly different setup (original example code) with \\RequirePackage{fix-cm} \\documentclass[12pt]{memoir} \\usepackage{fixltx2e}[2006/09/13] \\usepackage{amsmath} \\usepackage{txfonts} \\usepackage[only,llbracket,rrbracket,llparenthesis,rrparenthesis]{stmaryrd} \\usepackage{accsupp} in the preamble, one needs \\mkern-5.7mu in the fourth argument to \\mathchoice for \"correct\" scaling. To see what goes wrong in that case, it's best to include a line such as discontinuous small symbols in a footnote\\footnote{\\(\\scriptscriptstyle\\llbrace \\frac{a}{b} \\rrbrace\\)}. This might help a potential answerer test things out.", "Metric is continuous function Let $X$ be a metric space , $d$ is the metric , show that $d$ is a continuous function from $X\\times X$ to $R$. I think the definition is all we need , but I just don't know where to start , can anyone help me.", "How to interpret the output of XGBoost importance? I ran a xgboost model. I don't exactly know how to interpret the output of xgb.importance. What is the meaning of Gain, Cover, and Frequency and how do we interpret them? Also, what does Split, RealCover, and RealCover% mean? I have some extra parameters Are there any other parameters that can tell me more about feature importances? From the R documentation, I have some understanding that Gain is something similar to Information gain and Frequency is number of times a feature is used across all the trees. I have no idea what Cover is. I ran the example code given in the link (and also tried doing the same on the problem that I am working on), but the split definition given there did not match with the numbers that I calculated. importance_matrix Output: Feature Gain Cover Frequence 1: xxx 2.276101e-01 0.0618490331 1.913283e-02 2: xxxx 2.047495e-01 0.1337406946 1.373710e-01 3: xxxx 1.239551e-01 0.1032614896 1.319798e-01 4: xxxx 6.269780e-02 0.0431682707 1.098646e-01 5: xxxxx 6.004842e-02 0.0305611830 1.709108e-02 214: xxxxxxxxxx 4.599139e-06 0.0001551098 1.147052e-05 215: xxxxxxxxxx 4.500927e-06 0.0001665320 1.147052e-05 216: xxxxxxxxxxxx 3.899363e-06 0.0001536857 1.147052e-05 217: xxxxxxxxxxxxxx 3.619348e-06 0.0001808504 1.147052e-05 218: xxxxxxxxxxxxx 3.429679e-06 0.0001792233 1.147052e-05", "Read Value from URL in PHP", "Detect edits to add [SOLVED] or [RESOLVED] to the title and direct the user to add an answer Users often ask questions that they answer for themselves. Good for them. And good for us. Symptom The correct procedure seems to be: Write new answer to own question Wait two days Accept own answer The incorrect, but fairly popular, procedure seems to be: Edit the question to include the solution Put \"[SOLVED] or [RESOLVED]\" in the title Proposed solution Users should be warned when using the word \"solved\", delimited in any way, in a question title. This could be \"[SOLVED]\", \"(solved)\", or even \"Solved - \". I imagine this: The user tries to submit an edit that adds \"solved\" such that the word \"solved is delimited. The user is brought to a warning page. If the only edit to the question was appending new lines (such as adding an \"edit:\" paragraph), that edit is copied into a text box The page mentioned in 1 is shown as follows: $StackSite marks questions as answered when you accept an answer. You can accept an answer by clicking the green check mark next to that answer. There's no need to put \"SOLVED\" or \"RESOLVED\" in the title! Are you answering your own question? Create a proper answer to your question: Move your edit to a new answer. Write your answer. If nobody writes a more correct or thorough answer after two days, come back and accept your answer. By doing this, you remove your question from the Unanswered Questions list. You also allow other $StackSite users to vote your answer up. Thanks for helping out! TEXT BOX WITH EDITS GOES HERE, FOLLOWED BY \"POST YOUR ANSWER\" BUTTON Not answering your own question? Sorry for slowing you down. OVERVIEW OF EDIT, FOLLOWED BY \"SAVE EDITS\" BUTTON Discussion This would likely reduce the number of [RE]SOLVED questions that appear. However, it's unclear whether this should be a community moderation issue or a feature request issue. The increased engineering work required in building in the interstitial page is probably quite nontrivial, whereas this type of question makes up well under . Note: Google also provides a .", "How can I add a \"C\" wire to my thermostat? So, the spiffy new wi-fi thermostats want power on the C wire from thermostat, but the old thermostat doesn't have a C wire at it. What's the easiest way to add the C wire/24 volt to the thermostat location?", "Show that $E(X)=\\int_{0}^{\\infty}P(X\\ge x)\\,dx$ for non-negative random variable $X$", "How to install Windows 10 Home 19018 update? I'm using windows home edition, I have the latest update installed 1909. I want to install docker for windows 10 home edition. It keeps saying Docker Desktop requires Windows 10 Pro/Enterprise (15063+) or Windows 10 Home (19018+). Should I join Windows insider? How long should I wait for that update to be released if I don't want to join windows insider?", "How does Linux handle multiple consecutive path separators (/home////username///file)?", "How to compare a program's version in a shell script? Suppose I want to compare gcc version to see whether the system has the minimum version installed or not. To check the gcc version, I executed the following gcc --version | head -n1 | cut -d\" \" -f4 The output was 4.8.5 So, I wrote a simple if statement to check this version against some other value if [ \"$(gcc --version | head -n1 | cut -d\" \" -f4)\" -lt 5.0.0 ]; then echo \"Less than 5.0.0\" else echo \"Greater than 5.0.0\" fi But it throws an error: [: integer expression expected: 4.8.5 I understood my mistake that I was using strings to compare and the -lt requires integer. So, is there any other way to compare the versions?", "Apple Macbook Dual Monitor MST", "Find all possible solutions of $$2^x + 3^y = z^2.$$ My approach. First I substituted $x = 0$, and got the solution, then for $y = 0$. And for $x &gt; 0$ and $y &gt; 0$ , I just know the Pythagorean triple and got the solution as $(4,2,5)$ and $(4,2,-5)$. Please help me to solve it properly.", "Let $V$ be a representation with character $\\chi$. I would like to have a formula for the characters of the representations $\\mathrm{Sym}^m[V]$ and $\\wedge ^m[V]$ in terms of $\\chi$. Fulton and Harris presents such a formula for $m=2$, but not for general $m$. Is there a \"nice\" such expression? I found a paper by , but this doesn't seem to be what I'm looking for (it doesn't seem to give a general formula in terms of $\\chi$). In case the link does not work, here is the reference: X. Zhou, P. Pulay. Characters for Symmetric and Antisymmetric Higher Powers of Representations: Application to the Number of Anharmonic Force Constants in Symmetrical Molecules. Journal of Computational Chemistry, Vol 10, Issue 7, (1989).", "I am new to TeX/LaTeX. How do I install TeX on Windows (7)? It seems that there are many different implementations, so which one is best for my OS?", "Maximum and minimum distance of two points Consider six distinct points in a plane. Let $m$ and $M$ denote respectively the minimum and the maximum distance between any pair of points. Show that $M/m \\geqslant \\sqrt{3}$.", "I want to see you. I look forward to seeing you. How can one say \"to\" in the first sentence is an infinitive marker and in the second sentence a preposition when we are given just the following two sentences and are asked to fill in the blanks? I want to ____(see/seeing) you. I look forward to __(see/seeing) you.", "Use of Named Credentials seem to be tied to External Data Source" ]

[ "In Harry Potter and the Sorcerer's Stone, Nearly-Headless Nick and some other ghosts can visit the Hogwarts students, but why can't other deceased people - such as Harry's parents?", "If we set $A$ and $B$. Assuming that there exist an injective map from $A$ to $B$ and an injective map from $B$ to $A$. How to prove that there is a bijection between $A$ and $B$.", "Question list on Stack Overflow is not showing new question", "How to calculate the division and remainder of a big number manually Let $x = 2017^{2017}$. How can I manually determine: The remainder of the division of $x$ by $31$ The least significant digit of $x$", "Probability that all three shirts were worn Mr. Jones has three shirts: Red, Green and White. Each day he picks randomly a red shirt with probability of $\\frac{1}{2}$, green with probability of $\\frac{1}{3}$ and white with probability of $\\frac{1}{6}$. What is the probability that he wears all three shirts after 6 days? My try: $$\\binom{6}{1}\\binom{5}{1}\\binom{4}{1}\\frac{1}{2}\\cdot\\frac{1}{3}\\cdot\\frac{1}{6}\\cdot[\\binom{3}{2}(\\frac{1}{2})^2\\cdot[\\frac{1}{3}+\\frac{1}{6}]+[\\binom{3}{2}(\\frac{1}{3})^2\\cdot[\\frac{1}{2}+\\frac{1}{6}]+[\\binom{3}{2}(\\frac{1}{6})^2\\cdot[\\frac{1}{2}+\\frac{1}{3}]+\\binom{3}{1}\\binom{2}{1}\\frac{1}{2}\\cdot\\frac{1}{3}\\cdot\\frac{1}{6}]$$ First, we pick possessions for red, green and white. Then, we multiply it by the other combinations possible of the other three possessions left, and summing it up (I didn't count all possibilities). The problem is the answer is bigger than 1, so it must be wrong. Also, I guess there is more elegant way. Thanks in advance.", "The definite article implying the generic idea of something", "Why is travelling around the speed of light a problem? I don't fully understand what would happen if we could travel at the speed of light. But I saw somewhere here that it would mean events happen out of order. But why is this a problem. It is said that cause has to happen before the effect, but why does this have to be linear? And why is it that the speed of light is the maximum? I take it that light (photons?) are massless, so why can't they travel faster?", "On which Stack Exchange site can I ask customer service questions about product X or company Y? On which Stack Exchange site can I ask questions like When will [some new feature] for [some product] be released? Where can I download an update for [some product]? I'm getting errors when accessing the customer portal for [some company] – how can I fix this? Why was I banned for doing [some action] on [some platform]? Why is [some company] discontinuing [some product]? Why is [some company] giving away [some product] for free? What's the price for [some product]? or any other product support/customer service questions? It's not a product related to programming (or I've read on Meta Stack Overflow) so I know Stack Overflow isn't the right place. Which other site in the network will take these kind of questions?", "Why does Python code use len() function instead of a length method? I know that python has a len() function that is used to determine the size of a string, but I was wondering why it's not a method of the string object. Update Ok, I realized I was embarrassingly mistaken. __len__() is actually a method of a string object. It just seems weird to see object oriented code in Python using the len function on string objects. Furthermore, it's also weird to see __len__ as the name instead of just len.", "Can I run Ubuntu OS on a Android 4.0 tablet?", "Cannot inherit from multiple classes defining __slots__?", "How do I prevent mouse movement from waking up a suspended computer?", "Soql query on parents other child object I want to write a soql query , My scenario is as follows. I have three objects objectA,objectB,objectC. objectA is the parent object for both objectB,objectC. objectA - objectB (Master-detail relationship) objectA - objectC (Master-detail relationship)` ObjectB has two fields: Start_date__c End_date__c ObjectC has a field: Date__c Now i want to retrieve records with date__c in objectC those were in between start_date__c and end_date__c of objectB. how can i achieve such functionality .", "How can I get multiple stacked plots (ybar stacked, stack plots=y) in one diagram, such that there are multiple stacked bars for the same x-coordinate, each slightly shifted? Is there a way to reset pgfplot's zero levels after an \\addplot command, such that the next \\addplot[xhshift=...] doesn't add something to the current stack, but rather starts a fresh stack? FWIW, overlaying two plots with scale only axis won't help; I need this to work with groupplot", "Looking at moving my laundry upstairs, and the right answer is to combine two adjacent closets to get the width and move one of their walls a foot or two into the kitchen to get the depth. The kitchen floor is 10-inch-square tiles. It would be sort of nice if that continued on into the laundry closet. I do have a full bundle of spare tiles in the basement. Question: Could/should I plan on the new wall coming in on top of the existing tiles (presumably having to drill to secure the footer without shattering them), or should I plan on removing the ones under the footer and fitting cut pieces back in afterward?", "\"Oriented\" vs. \"orientated\" What are the origins of the word orientated? As far as I know, the correct spelling is oriented and orientated is not an alternative spelling but an error that is in common use. Is it for example more commonly used in a certain country or by a certain people? Is there a reason for people choosing to say or write orientated instead of oriented?", "Meta Meta Privilege I just took a look at meta today and noticed something weird in the meta privileges. If you look at the meta privilege list, you can see that at . I know that there is no meta for meta, and the link they give you in the privilege page leads you to meta.stackexchange.com, right where you started. Why do they have this privilege? I have a feeling that this is a bad recursive joke. You must be member of meta to get the privilege of being a member of meta! :)", "As we all know, immediate actions are just like swift actions, but can be performed outside of one's turn. However, unlike a swift action, an immediate action can be performed at any time - even if it's not your turn. However, it is still unclear if one can use an immediate action during someone else's action. For example: A monster swings at a conjurer. Can conjurer abrupt jaunt outside monster's reach right after the attack was rolled, thus wasting an attack? What about right after the damage was rolled, but not yet applied? What about casting celerity and baleful transposition on yourself and monster's ally so the monster would hit his ally, given high enough attack roll? Let's complicate a bit with a complex, full-round action on a monster's side. Can one use immediate action in between attacks in full attack? What about after movement part of a charge?", "Opt out of moderator election notifications", "I was speaking to an English learner and said, “All you have to do is read a lot.” And they thought that sentence wasn’t grammatically correct because I dropped the word to between is and read. They thought it should be “All you have to do is to read a lot.” That sounds weird to me. How do I explain to them the reason you drop the to? Or am I incorrect and it really should have a to?" ]

[ "Why is integration the inverse of differentiation Why is integration the inverse of differentiation, I mean why do I get the same function when I integrate and then differentiate the result?", "I have a new computer with a Seagate ST500DM002 SATA internal hard drive. I am trying to install Ubuntu 11.10 64-bit on it but the installer does not recognize/detect/see the hard drive. When I reach the Installation type step, the panel which is supposed to show devices and partitions looks empty. sudo fdisk -l shows only /dev/sda1, the USB drive from which I am running the installation. I have already tried the following two solutions without any success: sudo apt-get remove dmraid Switch the SATA mode in the BIOS from IDE to AHCI I am sure it's not a hardware related problem as I have already successfully installed another operating system on the same computer. The output of sudo lshw -class storage -class disk follows: *-ide UNCLAIMED description: IDE interface product: ASMedia Technology Inc. vendor: ASMedia Technology Inc. physical id: 0 bus info: pci@0000:06:00.0 version: 01 width: 32 bits clock: 33MHz capabilities: ide msi pm pciexpress cap_list configuration: latency=0 resources: ioport:d040(size=8) ioport:d030(size=4) ioport:d020(size=8) ioport:d010(size=4) ioport:d000(size=16) memory:fe400000-fe4001ff *-storage description: SATA controller product: 6 Series/C200 Series Chipset Family 6 port SATA AHCI Controller vendor: Intel Corporation physical id: 1f.2 bus info: pci@0000:00:1f.2 logical name: scsi1 version: 05 width: 32 bits clock: 66MHz capabilities: storage msi pm ahci_1.0 bus_master cap_list emulated configuration: driver=ahci latency=0 resources: irq:44 ioport:f0b0(size=8) ioport:f0a0(size=4) ioport:f090(size=8) ioport:f080(size=4) ioport:f060(size=32) memory:fe705000-fe7057ff *-cdrom description: DVD-RAM writer product: DVDRAM GH22NS70 vendor: HL-DT-ST physical id: 0.0.0 bus info: scsi@1:0.0.0 logical name: /dev/cdrom logical name: /dev/cdrw logical name: /dev/dvd logical name: /dev/dvdrw logical name: /dev/scd0 logical name: /dev/sr0 version: EX00 capabilities: removable audio cd-r cd-rw dvd dvd-r dvd-ram configuration: ansiversion=5 status=nodisc *-scsi:0 physical id: 1 bus info: usb@1:1.2 logical name: scsi6 capabilities: emulated scsi-host configuration: driver=usb-storage *-disk description: SCSI Disk physical id: 0.0.0 bus info: scsi@6:0.0.0 logical name: /dev/sda size: 14GiB (16GB) capabilities: partitioned partitioned:dos configuration: signature=0004e5a4 *-scsi:1 physical id: 2 bus info: usb@1:1.3 logical name: scsi7 capabilities: emulated scsi-host configuration: driver=usb-storage *-disk description: SCSI Disk product: Storage Device vendor: USB Mass physical id: 0.0.0 bus info: scsi@7:0.0.0 logical name: /dev/sdb capabilities: removable *-medium physical id: 0 logical name: /dev/sdb Any idea on what I could do to fix this problem?", "I make use of the view: \"taxonomy term\". Is there an easy way to also show the children of a term, next to the nodes beloging to this term? Example: Cars - Volvo --- Family_cars --- Sports_cars - Honda --- Parts --- ... Trucks - ... When you see the \"cars\" page I want to show all articles about cars (but not about Volvo, Honda, ...) AND I want to show the children (Volvo, Honda, ...) When you click one of these I want to show all the articles belonging with them, again with their children.", "Is there a good casual online place to practice/learn bridge? I know that Pogo.com (which powers Yahoo Games) has a long running online bridge game and that there are a handful of places for serious tournament/MasterPoint level bridge players online (though most seem based on software written a decade or more ago) but are there any places to play, practice and learn bridge in a more casual manner? Ideally via a well designed modern piece of software?", "The boundary of union is the union of boundaries when the sets have disjoint closures", "Most descriptions of SIGTERM and SIGKILL point out that SIGKILL, In contrast to SIGTERM and SIGINT, [...] cannot be caught or ignored [...] () Is this the only difference between SIGTERM and SIGKILL? In particular, if a process does not install a SIGTERM handler, is there any difference at all between sending SIGTERM or SIGKILL to the process?", "What's the difference between scaling text via transform and changing font size? Is there a difference between using Transform commands to scale text and altering the size of the font via Character panels? I'm working in Photoshop CC", "Why does comparing strings using either '==' or 'is' sometimes produce a different result?", "Add a message when posting to old questions with more than N answers", "My system is not dual-boot, I run a standard Ubuntu desktop system \"on the metal\" (I think running it in a VM is the same). Pressing c while booting does not cause the GRUB menu to appear (which I believe it does for a dual-boot system). How can I get the GRUB-menu to present itself on a single-boot system?", "Z-axis issue with the floating review info panel, permits various elements to flow over it I was having a look at an old question of mine when I browsed the from the timeline. I scrolled downwards and realized the Review completed panel comes along for the ride. While that might be , tags flowing over top of it as pictured below probably isn't. Here's a .gif of the Question and Duplicate tabs flowing over it as well. Note that the timeline button also flows over. If vote buttons are present, they will also flow over it. Reproduced on Chrome and Microsoft Edge. Update Per by Tiago Martins Peres, this issue also happens in other Review types, namely Late Answers, First Posts and Low Quality Posts. In addition to that, it is causing the action buttons on reviews to become unclickable if you scroll low enough. As a temporary workaround, you can use 's , which this issue.", "This is a canonical question that will hopefully encompass all of the questions we get asking us to determine what year a bicycle was manufactured (how old is my bike, how old is my frame, etc.). Each \"answer\" should address a different way to determine the manufacturing year of a bicycle. To some extent, these will also help you narrow down the model as well as it will tell you what distinguishing features to look at. The span of answers would include things such as: Skiptooth cranks Cartridge bottom brackets (BB30/90 etc) Elliptical chainring Quick releases versus contemporary through-axles How the steerer attaches to the fork (quill vs. threadless) Braking system (especially with mountain bikes: v-brake, direct pull, etc.) Shifting ramps and pins on cassettes/sprockets and chainrings (versus flat sprockets) Frame material (e.g., shift from tubular steel to use of CF and hydroformed aluminium) Frame tubing type (e.g. Reynolds 531 tubing introduced around 1934, still used today; Reynolds 501 tubing introduced around 1983). So a frame with an original 501 decal can't be from the 70', 531 decal doesn't help as much because of the range of years produced. Also, see Decals. *Decals: style/design, amount, placement, color, etc. can help not only determine models, but also year of manufacture. Many changed decal design for the same model bike often yearly, with special/limited editions even more specific. This applies only if decals are original or have been replaced with the identical design. Tubing decals (Reynolds, Columbus, etc.) also changed designs for same tubing made in different years, although the changes aren't made as often, and manufacturers didn't always put tubing Brand decals on every model. Earlier bikes tended to have less fancy, less colorful, less quantity of decals. Headbadges: most early bikes had actual \"badges\", often quite detailed and fancy, made of metal, then plastic, and finally just using decals on the headtube. Most bikes lost their metal badges in the 60's and early 70's, although some brands still have actual badges to this day, but in general a real badge indicates an earlier model bike. Dropout style (including the later inclusion of lawyers lips) Presence or absence of CPSC reflectors (USA only) Manufacturing method (shift from lugs to TIG welding, for example) Number of gears (shift from 2x5 ten-speed to 3x8, 2x9, 1x11, etc.) Inspection of lug design: pantographs, cut-out, stampings, custom brazing/filing, chrome, fork crow n sweep, etc. Frame/Fork Braze-ons. Race bikes tended have less braze-ons the earlier the year of manufacture. Most 60's racers and earlier had few or none with cable guides/stops, shifters, bidons, etc. being clamp-on. By the 80's if it was clamp-on, it was a sign of very cheap models and most frames had braze-ons for all cables, with multiple bottle and accessory bosses depending on style and use. and so forth. Please edit this question if you have an answer that isn't in the index above. A couple of caveats: A previous owner could have replaced or upgraded components on a bicycle, so this guide only applies to original equipment There is a delay between the introduction of a technology (such as indexed shifting) and when manufacturers start selling products that use it. Low-end manufacturers may continue using technology that is severely outdated (such as one-piece cranks, freewheels, or quill stems) because it is cheaper to do so. A number of bikes are built in a Retro style, but with modern components. Dutch bikes, trendy coffee cruisers, and beach cruisers may be modern but appear to be 1950s styling. These tend to have modern rims and brakes as a giveaway. Note that bicycles.stackexchange does not do valuations of bicycles. How much your bicycle is worth depends on the location of the buyer and seller, how much the buyer wants the bike, etc. etc. etc.", "Change Default Scrolling Behavior of UITableView Section Header", "Hi I would like to know whether the trace of the inverse of a symmetric positive definite matrix $\\mathrm{trace}(S^{-1})$ is convex. Actually I know that the trace of a symmetric positive definite matrix $S\\in M_{m,m}$ is convex since we can find $B\\in M_{n,m}$ such that $S=B^T\\times B$ then we can write the trace as the sum of scalar quadratic forms, i.e. $\\mathrm{trace}(S)=\\mathrm{trace}(B^T\\times B)=\\sum_{j=1}^mb_j^T\\times b_j$ where $b_j$ is the $j^{th}$ column of $B$. for instance if we have $trace([\\begin{array}{cc} 1 &amp; 2 \\\\ 3 &amp; 4 \\\\ \\end{array}] \\times [\\begin{array}{cc} 1 &amp; 3 \\\\ 2 &amp; 4 \\\\ \\end{array}])= [\\begin{array}{cc} 1 &amp; 2 \\\\ \\end{array}]\\times [\\begin{array}{c} 1 \\\\ 2 \\\\ \\end{array}]+ [\\begin{array}{cc} 3 &amp; 4 \\\\ \\end{array}]\\times [\\begin{array}{c} 3 \\\\ 4 \\\\ \\end{array}]=30$ And so I wonder if $\\mathrm{trace}(S^{-1})$ is convex too..", "In C++, sizeof('a') == sizeof(char) == 1. This makes intuitive sense, since 'a' is a character literal, and sizeof(char) == 1 as defined by the standard. In C however, sizeof('a') == sizeof(int). That is, it appears that C character literals are actually integers. Does anyone know why? I can find plenty of mentions of this C quirk but no explanation for why it exists.", "I have the following problem: Let $(M, \\omega)$ be a symplectic manifold. How can I show $$\\omega^n=\\underbrace{\\omega\\wedge \\ldots\\wedge \\omega}_{n-times},$$ satisfies $\\omega^n(p)\\neq 0$ for all $p\\in M$. I believe that is not too dificult but I'm not used with exterior product.. Any help will be valuable... This is important because the nondegeneracy condition on $ω$ is equivalent to the condition that M has an even dimension $2n$ and the top wedge product $\\omega^n$ is nowhere vanishing on M, i.e., $ω^n$ is a volume form. In particular, $M$ must be orientable and is canonically oriented by $\\omega^n$.", "What is the difference between Ubuntu and its derivatives? What different Ubuntu derivatives are there? And what is special with them?", "Prove: $\\displaystyle\\sum_{k=1}^n k k!=(n+1)!-1$ (preferably combinatorially) It's pretty easy to think of a story for the RHS: arrange $n+1$ people in a row and remove the the option of everyone arranged to height from shortest to highest, but it doesn't hold up for the LHS. Alternatively, trying to visualize the LHS, I noticed that it's like a right angle tetrahedra: 1 2!+2! 3!+3!+3! ... But it doesn't help to see a connection to the RHS. Note: no integrals or gamma function nor use of other identities without proving them nor generating functions.", "I have answered 'No' to Siri initial prompt, but I can still see it in my process list. I've tried to kill it, but it loads again immediately. How can I unload and remove Siri from my Mac?", "I have Ubuntu 16.04 with GNOME shell. I set ctrl+shift for the \"Modifiers-only switch to next source\" option. This shortcut conflicts with apps hot-keys. I can't use ctrl+shift+i to open devtools in Chrome, it just switches the layout. In VS code IDE if I press shortcuts with ctrl+shift (for example ctrl+shift+f), shortcuts work but always switch a keyboard layout. When I used Windows this problem didn't exist. Can I set the ctrl+shift shortcut in such a way that it causes a switch action only after the keys are released and only if this 2 keys were pressed (without additional keys)?" ]

[ "How come unpolarized light does not undergo destructive interference? As far as I know, unpolarized light is defined as light which has no clear axis of polarization, but electric field vectors in all directions. However, I also know that electric fields can be superpositioned. So this leads me to the conclusion that if unpolarized light has equal $\\vec E$ vectors in all directions, they should cancel. Obviously, though, this is wrong (we've got light!). What's the explanation?", "Determining the number of bit strings of length n that contains no adjacent 0s • $C_n =$ this number of bit strings • A binary string with no adjacent 0s is constructed by Adding “1” to any string w of length $n-1$ satisfying the condition, or Adding “10” to any string v of length $n-2$ satisfying the condition I still don't find that intuitive at all. Why adding up $C_{n-1} + C_{n-2}$ results in $C_n$? I have tried my best and asked my friends for help, but they find the formula unintuitive as well. Could anyone here come up with a clear explanation? Thanks!", "the composition was defined as follow: (a,b) \\in (R;S) &lt;=&gt; there is c | (a,c) \\in R and (c,b) \\in S . If our two relations R and S are two convex polygon Is there a geometric interpretation of the composition of two convex polygon ? for example : the green polygon was the result of composition. How can i describe geometrically the result !!!", "I've been using Ubuntu for a few years now, but I just installed Version 16.04, and I've been having a lot of issues. I'm not a command line expert, but I tried to install some software last night, and it is creating issues (and also not working properly). When I run sudo apt-get -f install, I see the following message: Reading package lists... Done Building dependency tree Reading state information... Done Correcting dependencies... Done The following additional packages will be installed: lua-event lua-expat lua-filesystem lua-sec lua-socket lua5.1 prosody Suggested packages: lua-zlib lua-dbi-postgresql lua-dbi-mysql lua-dbi-sqlite3 The following packages will be REMOVED: jitsi-meet-tokens The following NEW packages will be installed: lua-event lua-expat lua-filesystem lua-sec lua-socket lua5.1 prosody 0 upgraded, 7 newly installed, 1 to remove and 22 not upgraded. 3 not fully installed or removed. Need to get 0 B/413 kB of archives. After this operation, 2,296 kB of additional disk space will be used. Do you want to continue? [Y/n] Y (Reading database ... 176266 files and directories currently installed.) Removing jitsi-meet-tokens (1.0.962-1) ... dpkg: error processing package jitsi-meet-tokens (--remove): subprocess installed post-removal script returned error exit status 10 Errors were encountered while processing: jitsi-meet-tokens E: Sub-process /usr/bin/dpkg returned an error code (1) Can someone help me figure out what I need to do to get this resolved? I'm fine with deleting jitsi, but I'm not sure if that will correct the problem. Currently there is a red circle with a line through it in the upper right corner that indicates there may be installed packages with unmet dependencies.", "Accessing class members on a NULL pointer", "Sounds of the letter a How can I know, precisely, when to differentiate the sounds of the letter a, like in: apple and vault?", "How can I make a camera the active one? I have multiple cameras in a scene. What I want to do is to change which one is active. This way I can view the scene from different angles. How would I do this?", "I thought of this a while ago, but can't make up a proof or a counterexample. Does anyone know more about this? $$\\sqrt{a+b} \\le \\sqrt a + \\sqrt b , \\forall a,b \\in \\mathbb R_+$$ Moreover, what happens with more variables? Say: $$\\sqrt{x_1+x_2+...+x_n} \\le \\sqrt x_1 +\\sqrt x_2 + ... + \\sqrt x_n $$ with $ x_i \\in\\mathbb R_+ \\forall i \\in \\{1,2,...,n\\} $ Or when $i = \\mathbb N$ PS: I tried looking on the internet for this but I don't know how I would call this.", "Deciphering the RSA encrypted message from three different public keys I have three different 1024-bit public keys with common exponent $e$ but different moduli. A message $m$ is encrypted (without padding) using the three keys, which results in three different encrypted messages. Given the three pairs of public keys $(N_i,e)$ and the encrypted messages $c_i=m^e\\bmod N_i$ , how do I decipher the original message $m$ ?", "How do users navigate to Meta? How do you expect users to: Know that a site's meta-site exists (and what it's for)? Find the hyperlink to the meta-site? I know it exists, of course, and how to get there; I'm wondering how (or even whether) you expect new or naive users to do that. I think there isn't a link to Meta from the main site, am I right (except one link in the \"list of all 171 Stack Exchange sites\" drop-down menu on the toolbar)? Sometimes I tell people to post a question on Meta instead of on the main site -- I don't realise that they may not know that Meta exists, and that if they do (because they've been there before) they don't know how to get there (because they haven't yet investigated everything on the toolbar).", "How do I setup keyboard macros? In my daily life I'm always typing &lt;kbd&gt;Keyboard Character&lt;/kbd&gt; and I'd like to set up a macro in Ubuntu to automatically enter &lt;kbd&gt; &lt;/kbd&gt;. I'd like to assign it to say Shift+Control+K or whatever keyboard control character combination isn't assigned and already used by Ubuntu. Back in the day of TSR (Terminate and Stay Resident) MS-DOS programs this was possible. Certainly it must be in Ubuntu too? Do I have to write a daemon to accomplish this? I found other questions with no answers: , I found a similar question with an answer: . However that question stipulated the answer could not be AutoKey.", "Presentation $\\langle x,y,z\\mid xyx^{-1}y^{-2},yzy^{-1}z^{-2},zxz^{-1}x^{-2}\\rangle$ of group equal to trivial group Problem: Show that the group given by the presentation $$\\langle x,y,z \\mid xyx^{-1}y^{-2}\\, , \\, yzy^{-1}z^{-2}\\, , \\, zxz^{-1}x^{-2} \\rangle $$ is equivalent to the trivial group. I have tried all sorts of manners to try to show that the relations given by the presentation above imply that $x=y=z=e$. However, I am stuck and would appreciate any hints as to how I should move forward.", "Search functionality in lightning:datatable? Is there a way to search across all rows/columns in a lightning:datatable to narrow down the list, just like jQuery DataTables? If so, how do implement that? Can I somehow do it all on the client-side to make it super fast (some sort of DOM manipulation) I'm having some issues with the lightning:datatable not updating. I have attached my code below, maybe you can help me spot the issue: Markup: &lt;aura:component extends=\"c:Base\" controller=\"AccountBrowserForm\"&gt; &lt;aura:handler name=\"init\" value=\"{! this }\" action=\"{! c.doInit }\"/&gt; &lt;aura:attribute name=\"selectedAccountId\" type=\"Id\" access=\"public\" /&gt; &lt;aura:attribute name=\"accounts\" type=\"Object\"/&gt; &lt;aura:attribute name=\"mycolumns\" type=\"List\"/&gt; &lt;aura:attribute name=\"sortedBy\" type=\"String\" /&gt; &lt;aura:attribute name=\"sortedDirection\" type=\"Boolean\" default=\"true\" /&gt; &lt;aura:registerEvent name=\"AccountFilterChange\" type=\"c:AccountFilterChange\" /&gt; &lt;aura:attribute name=\"backingdata\" type=\"List\" /&gt; &lt;aura:attribute name=\"filter\" type=\"String\" /&gt; &lt;lightning:input type=\"text\" onchange=\"{!c.filter}\" value=\"{!v.filter}\" label=\"Filter\" /&gt; &lt;lightning:datatable aura:id=\"lightningTable\" data=\"{! v.accounts }\" columns=\"{! v.mycolumns }\" keyField=\"Id\" onrowaction=\"{! c.handleRowAction }\" onsort=\"{!c.updateColumnSorting}\" sortedBy=\"{!v.sortedBy}\" sortedDirection=\"{!v.sortedDirection}\" hideCheckboxColumn=\"true\" /&gt; Controller: doInit: function (component, event, helper) { helper.callServer(component, \"c.getAccounts\", $A.getCallback(function (response) { component.set(\"v.accounts\", response); component.set(\"v.backingdata\", response); console.log(component.get(\"v.backingdata\") + \" /// BACKING DATA INSIDE \") console.log(component.get(\"v.accounts\") + \" // ACCOUTN DATA INSIDE\") component.set('v.mycolumns', [{ type: \"button\", typeAttributes: { label: '', iconName: 'utility:add', name: 'selectRecord', title: 'selectRecord', disabled: false, value: 'edit', variant: { fieldName: 'variantValue' }, } }, {label: 'Name', fieldName: 'Name', type: 'text', sortable: true}, {label: 'Street', fieldName: 'BillingStreet', type: 'text', sortable: true}, {label: 'Postal Code', fieldName: 'BillingPostalCode', type: 'text', sortable: true}, {label: 'City', fieldName: 'BillingCity', type: 'text', sortable: true}, {label: 'Country', fieldName: 'BillingCountry', type: 'text', sortable: true}, ]); console.log(component.get(\"v.backingdata\") + \" *** BACKING DATA OUTSIDE *** \") console.log(component.get(\"v.accounts\") + \" *** ACCOUNT DATA OUTSIDE *** \") })) }, filter: function (component, event, helper) { var data = component.get(\"v.backingdata\"), term = component.get(\"v.filter\"), results = data, regex; try { regex = new RegExp(term, \"i\"); // filter checks each row, constructs new array where function returns true results = data.filter(row =&gt; regex.test(row.name) || regex.test(row.age.toString())); } catch (e) { // invalid regex, use full list } component.set(\"v.accounts\", results); }, For some reason the filter function is completely unresponsive. Also, does it matter that I'm populating the component with a response from a callback function. @sfdcfox, I noticed in your example that you simple created an array with dummy data. My \"myaccounts\" attribute is of type object", "I found the following proof arguing for the irrationality of $\\sqrt{2}$. Suppose for the sake of contradiction that $\\sqrt{2}$ is rational, and choose the least integer $q &gt; 0$ such that $(\\sqrt{2} - 1)q$ is a nonnegative integer. Let $q'::= (\\sqrt{2} - 1)q$. Clearly $0 &lt; q' &lt; q$. But an easy computation shows that $(\\sqrt{2} - 1)q'$ is a nonnegative integer, contradicting the minimality of $q$. Clearly, this is a vague proof in that it expects the reader to work out the math involved on his own. I took that as an exercise and worked out the following: Assuming $\\sqrt{2}$ to be rational, let $$\\sqrt{2} = \\frac{p}{q}$$ where $p$ and $q$ are least possible integers. Clearly then, $\\sqrt{2} - 1$ would also be rational, $$\\sqrt{2} - 1 = \\frac{p-q}{q}$$ where both $(p-q)$ and $q$ are also integers. Multiplying both sides by $q$, we get $$(\\sqrt{2} - 1)q = (p-q) = q'$$ where $q'$ is an integer. Using, $2&gt;\\sqrt{2} &gt; 1$ , we get $$1&gt;\\sqrt{2}-1&gt;0$$ proving that $q'$ is a non-negative integer. As stated in the proof, computing $(\\sqrt{2}-1)q'$ we get, $$(\\sqrt{2}-1)q' = \\frac{(p-q)^2}{q}$$which is not necessarily an integer (in fact necessarily not an integer). However, the proof claims it to be. Am I missing something or something is wrong with how I proceeded? Here is a link to the textbook where I found this proof: , (p 32, problem 1.14). P.S. This is my first post here and my first time with TeX. I'd also like to know if there is anything wrong with the way my question is presented.", "Recently, I was doing my homework and I found out that Torque can be calculated using $\\tau = rF$. This means the units of torque are Newton meters. Work &amp; Energy are also measured in Newton meters which are Joules. However, torque isn't a measure of energy. I am really confused as why it isn't measured in Joules.", "How do you get JavaScript/jQuery Intellisense Working in Visual Studio 2008?", "Can I acquire a Windows 8.1 licence by free upgrade from 7 to 10, then downgrading So, I have Windows 7 pro, and I'm looking to upgrade so that I can use some of the apps that are only available in Windows 8+. I considered just taking advantage of the free Windows 10 upgrade, and actually installed it at one point, but then I found out that there's forced automatic updates and decided that wasn't for me(I'm a bit paranoid after Android 4.4.4 killed Flash Player without telling me. :P). So, I did some research. From what I read, the Windows 10 upgrade \"consumes\" your Windows 7 license into a Windows 10 license, and so even if you revert back after upgrading then you can still change your mind later and jump back to Windows 10. () I also read that Windows 10 has \"downgrade\" rights to Windows 8 and Windows 7, which to my understanding meant that if you have a Windows 10 key, you can also use it to install Windows 8 or 7 if you want. () My plan for the process is re-upgrade to 10, pull the license key, downgrade to 8 and use the license key, then upgrade to 8.1 via Windows Store, and end up on 8.1. So my questions are: Is this possible? Will it wipe all my data in the process?(not a dealbreaker if it does, but I'd need to know that so I can back it up) Do I need to re-upgrade to 10 in order to downgrade to 8? Any input is definitely appreciated. Thanks!", "Why does Unix store timestamps in a signed integer? Why is a signed integer used to represent timestamps? There is a clearly defined start at 1970 that's represented as 0, so why would we need numbers before that? Are negative timestamps used anywhere?", "What steps can I take to try to recover lost or inaccessible data from any storage device? Answers: This applies to any computer storage device, e.g. internal/external hard drives, USB sticks, flash memory. The most important thing is to STOP using it, any type of I/O can ruin your chances of a recovery. We have separate questions covering common problems with USB flash drives in greater detail:", "I read about Java's type erasure . When does type erasure occur? At compile time or runtime? When the class is loaded? When the class is instantiated? A lot of sites (including the official tutorial mentioned above) say type erasure occurs at compile time. If the type information is completely removed at compile time, how does the JDK check type compatibility when a method using generics is invoked with no type information or wrong type information? Consider the following example: Say class A has a method, empty(Box&lt;?&nbsp;extends&nbsp;Number&gt;&nbsp;b). We compile A.java and get the class file A.class. public class A { public static void empty(Box&lt;? extends Number&gt; b) {} } public class Box&lt;T&gt; {} Now we create another class B which invokes the method empty with a non-parameterized argument (raw type): empty(new Box()). If we compile B.java with A.class in the classpath, javac is smart enough to raise a warning. So A.class has some type information stored in it. public class B { public static void invoke() { // java: unchecked method invocation: // method empty in class A is applied to given types // required: Box&lt;? extends java.lang.Number&gt; // found: Box // java: unchecked conversion // required: Box&lt;? extends java.lang.Number&gt; // found: Box A.empty(new Box()); } } My guess would be that type erasure occurs when the class is loaded, but it is just a guess. So when does it happen?" ]

[ "What is the \"?\" symbol in URL used for in php?", "Equivalent of typedef in C# Is there a typedef equivalent in C#, or someway to get some sort of similar behaviour? I've done some googling, but everywhere I look seems to be negative. Currently I have a situation similar to the following: class GenericClass&lt;T&gt; { public event EventHandler&lt;EventData&gt; MyEvent; public class EventData : EventArgs { /* snip */ } // ... snip } Now, it doesn't take a rocket scientist to figure out that this can very quickly lead to a lot of typing (apologies for the horrible pun) when trying to implement a handler for that event. It'd end up being something like this: GenericClass&lt;int&gt; gcInt = new GenericClass&lt;int&gt;; gcInt.MyEvent += new EventHandler&lt;GenericClass&lt;int&gt;.EventData&gt;(gcInt_MyEvent); // ... private void gcInt_MyEvent(object sender, GenericClass&lt;int&gt;.EventData e) { throw new NotImplementedException(); } Except, in my case, I was already using a complex type, not just an int. It'd be nice if it were possible to simplify this a little... Edit: ie. perhaps typedefing the EventHandler instead of needing to redefine it to get similar behaviour.", "Was it just coincidence that Tahir Mahmood went on stage? In episode 3 of “Bodyguard,” Tahir Mahmood steps onto stage at St. Mary’s college as the Home Secretary is speaking and the two of them, plus others, are blown up by a bomb. In the next episode we discover that the stage had a weight trigger and that his arrival set it off. This heavily implies that whoever asked him to go on stage was affiliated with those who planted the bomb. We know that Mahmood was sent on stage by advisor Rob Macdonald as part of a scheme, together with other members of the home secretary’s staff, to embarrass her. The audience knows that some of the people in on this scheme have been plotting with the U.K. security services. This, together with interference in video recordings of the event, characteristic of the security services, implicates the security services in the assassination. In the final episode it is revealed that the bomb had been set by members of an organized crime gang who had gotten the explosives from an Islamic terrorist. A senior member of the police force had been helping them by leaking information. So, were the security services involved? If so, why? If not, who got Mahmood to go up on the stage? Was it just coincidence that he went up there at the right time?", "If there is a wizard that, by some means, has acquired proficiency in the use of shields, can said wizard use his shield in one hand and his arcane focus quarterstaff in the other and still cast somatic component spells? Since the quarterstaff has been crafted to also be an arcane focus, and the Sage Advice Compendium states that you can provide the somatic components of spells with the same hand wielding the arcane focus, in this case an arcane focus quarterstaff, could that wizard still be able to perform somatic component spells while using a shield in the other? I understand War Caster is the feat that allows you to cast somatic component spells even while using a shield and weapon or two weapons in each hand, but is this a simple way around those rules seeing as this \"weapon\" is your arcane focus? I would like to believe it is not, but I'm not fully fluent in the ways of spellcasting.", "What is a feminine version of 'guys'? I commonly use the word 'guys' to refer to a group of males colloquially. It's colloquial but not rude, off putting, condescending, patronizing (though I wouldn't use it with a group of men at a board meeting (hypothetically of course), unless I knew them). So, some that I would not consider as replacements would be buddies: too old-fashioned dudes: too informal boys: too patronizing men, gentlemen: too formal or false respect I realized that I had also been using it for any group of people, males and females, even just females. It worked for me and I didn't think of the gender implications, that women might not care for it. No one ever complained, directly or indirectly (rule of life: sometimes people don't complain about things they should). But it occurred to me (maybe by reading something that sparked realization) that the intended hearers might not all care for it. What might be a female gendered or non-gendered version of 'guys'? Some that I've considered don't feel right about (though these may be reasonable answers) are: dolls: too old-fashioned babes: too informal ladies: too formal or I've heard from women, too creepy women: too factual girls: too patronizing (as much as 'boys') everyone, you all: too bland y'all: perfectly non-sexist but too regional (might work, but not everywhere) Hopefully I haven't eliminated all the possibilities -- any suggestions?", "How to prove this inequality $\\left|x\\sin{\\frac{1}{x}}-y\\sin{\\frac{1}{y}}\\right|<2\\sqrt{|x-y|}$? For any real numbers $x,y\\neq 0$,show that $$\\left|x\\sin{\\dfrac{1}{x}}-y\\sin{\\dfrac{1}{y}}\\right|&lt;2\\sqrt{|x-y|}$$ I found this problem when I dealt with . But I can't prove it. Maybe the constant $2$ on the right hand side can be replaced by the better constant $\\sqrt{2}$? Thank you.", "Canonical has recently announced , which is Ubuntu with a specific interface for mobile devices. Where can I get phones with this version of Ubuntu pre-installed? If no devices are available yet, where can I pre-order one?", "Shapefile layer no longer editable (toggle edit option greyed out) in QGIS?", "I would like to think that some of the software I'm writing today will be used in 30 years. But I am also aware that a lot of it is based upon the UNIX tradition of exposing time as the number of seconds since 1970. #include &lt;stdio.h&gt; #include &lt;time.h&gt; #include &lt;limits.h&gt; void print(time_t rt) { struct tm * t = gmtime(&amp;rt); puts(asctime(t)); } int main() { print(0); print(time(0)); print(LONG_MAX); print(LONG_MAX+1); } Execution results in: Thu Jan 1 00:00:00 1970 Sat Aug 30 18:37:08 2008 Tue Jan 19 03:14:07 2038 Fri Dec 13 20:45:52 1901 The functions ctime(), gmtime(), and localtime() all take as an argument a time value representing the time in seconds since the Epoch (00:00:00 UTC, January 1, 1970; see time(3) ). I wonder if there is anything proactive to do in this area as a programmer, or are we to trust that all software systems (aka Operating Systems) will some how be magically upgraded in the future? Update It would seem that indeed 64-bit systems are safe from this: import java.util.*; class TimeTest { public static void main(String[] args) { print(0); print(System.currentTimeMillis()); print(Long.MAX_VALUE); print(Long.MAX_VALUE + 1); } static void print(long l) { System.out.println(new Date(l)); } } Wed Dec 31 16:00:00 PST 1969 Sat Aug 30 12:02:40 PDT 2008 Sat Aug 16 23:12:55 PST 292278994 Sun Dec 02 08:47:04 PST 292269055 But what about the year 292278994?", "Aware abbreviating those commands need not always be helpful, I would like to know how to abbreviate them? The following is what I tried, which does not work: \\documentclass[11pt,handout]{beamer} \\newcommand{\\bframe}{\\begin{frame}} \\newcommand{\\eframe}{\\end{frame}} \\newcommand{\\ftitle}{\\frametitle} \\author{Author} \\title{Title} \\begin{document} \\maketitle \\begin{frame} \\frametitle{Outline} \\end{frame} \\bframe \\ftitle{Introduction} \\eframe \\end{document} At first I thought it might be the case that commands such as \\bframe was already defined. But using \\def instead still gives no desired result.", "Switching languages in bibliography with biblatex I would like to have a bibliography with both Cyrillic and Latin and the main document language being English. How can I make biblatex to automatically switch between languages? (without using XeTeX as suggested by some) The minimal example returns an error if the main language is English. However, with the main language being Russian the document works. \\documentclass{article} \\usepackage[utf8]{inputenc} \\usepackage[russian,english]{babel} \\usepackage[backend = biber,babel=other]{biblatex} \\usepackage{csquotes} \\addbibresource{library.bib} \\begin{document} %\\selectlanguage{russian} %if the main document language is Russian the bibliography is compiled without any problem. This is a test. \\parencite{Bara2006,Baranov2001} \\printbibliography \\end{document} The .bib entries are @book{Bara2006, address = {New York}, author = {Bara, Judith}, publisher = {Routledge}, title = {{English Citation entry}}, year = {2006} } @book{Baranov2001, address = {Санкт-Петербугр}, author = {Баранов, Николай А}, title = {{Эволюция взглядов}}, year = {2001} }", "Matching a sentence with grep", "Blaise Pascal's famous wager was that even if the existence of God cannot be determined through reason, a rational person should wager as though God exists, because living life accordingly has everything to gain, and nothing to lose. What logical flaws and/or fallacies (if any) are committed in making this argument?", "How do TTL NAND gates work? This is supposed to be a simple NAND gate. I understand how the output is 1 if one of the inputs is zero but if both inputs are 1 then the base of Q1 is supposed to be zero. This is what I don't understand. I know that Q2 and Q3 will be in cut off so the base of Q1 is floating. If that is true, how is it zero then?When A and B are open does current flow through Q2 Q3 via R1 to turn on Q1?", "I have a Fujitsu laptop and all was working fine until I ended teamviewer. On the keyboard it has a numberpad on some of the letters which you press the Fn button to use. The system is acting like I have the Fn key pressed and I get numbers shown when it should be letters. If I press the Fn key the numbers go to letters. The Fn key is not stuck down. Is there a way to reset keyboard settings or a known fix. The operating system is Ubuntu 11.04 Natty.", "I am looking for an adjective/noun for someone who is able to speak/ makes speeches very well and uses words effectively to influence/impress people.", "Revision history & community wiki links show the same page", "latex : Exclude draftwatermark from specific pages I am using draftwatermark package. Is there any option to exclude watermark from some specific pages? Say no watermark from pg 3-4. I can not use xwatermark package. It conflicts with the geometry package of my document. MWE: \\documentclass[12pt,a4paper]{exam} \\usepackage{draftwatermark} \\usepackage{lipsum} \\SetWatermarkAngle{45} \\SetWatermarkLightness{.8} \\SetWatermarkFontSize{10cm} \\SetWatermarkScale{5} \\SetWatermarkText{\\tt{12345}} \\begin{document} \\lipsum[1-20] \\end{document}", "I read this set of stories in the 80's. What I recall is this: A planet where the ruling caste was made up of humanoid women. These women would, as almost pubescent girls, go out into the wilderness with only a spear and attempt to kill an animal in a life or death struggle. When it happened, they would burst open a DNA packet in themselves that caused them to rapidly mature, their skin to become bronze colored, and give them some kinds of other \"powers\", I think over fire. They were called \"Bahronas\", I think. The population of this planet was primitive, but they were in contact with an advanced humanoid species, I think of actual homo-sapiens, who were there observing and advising them. The advanced species wasn't allowed to intervene, just advise and watch. The main character was a castaway boy, crash landed on their planet and stranded. He became friendly with the ruling family of Bahronas and entered their confidence. We find out through the course of the story that he's been genetically engineered and is not a normal boy. At some point, the advanced species notices him and explains that he is a clone of a famous explorer and a spy, and they explain that they won't do anything in front of him. The central part of the story is something of a blur, but, the final part of the story is told in a dramatically different style and shifts to a planet populated by catlike creatures who live in boughs of silk scarves, some of which sing. THey are recording devices which play back the songs. On this planet, there is another silk scarf, a white one, which doesn't play a song at all. The cat creatures are greatly disturbed by it when they hear it's message, which they don't understand. The narrator then goes on to say that it's a spoken word recording, made by the explorer which the boy was a clone of, explaining that he is captured and held hostage on the planet which makes the scarves, and forced to help make them (I think.)", "Can one introduce magnetic monopoles without Dirac strings? To introduce magnetic monopoles in Maxwell equations, Dirac uses special strings, that are singularities in space, allowing potentials to be gauge potentials. A consequence of this is the quantization of charge. Okay, it looks great. But is this the only way to introduce magnetic monopoles?" ]

[ "How to make crs transformation of a QgsVectorLayer? I need to transform QgsVectorLayers in python from one crs into another crs. By googling I found the following solution (), which works for points only: crsSrc = QgsCoordinateReferenceSystem(4326) # WGS 84 crsDest = QgsCoordinateReferenceSystem(32633) # WGS 84 / UTM zone 33N xform = QgsCoordinateTransform(crsSrc, crsDest) pt1 = xform.transform(QgsPoint(18,5)) Is there a way to make a crs transformation of an entire layer?", "Is it possible to have test error lower than training error? I have a classification problem with 2000 samples, 500 of which are positives, 1500 are negatives. I split my data into 70% training data, 30% test data. Run random forest with 200 estimators and cv=10. I did this several times and compared the recall and precision score and notice the scores for my test set is significantly better. Is this possible?", "UTF-8 all the way through I'm setting up a new server and want to support UTF-8 fully in my web application. I have tried this in the past on existing servers and always seem to end up having to fall back to ISO-8859-1. Where exactly do I need to set the encoding/charsets? I'm aware that I need to configure Apache, MySQL, and PHP to do this — is there some standard checklist I can follow, or perhaps troubleshoot where the mismatches occur? This is for a new Linux server, running MySQL 5, PHP, 5 and Apache 2.", "I've been searching for a quantum algorithm to compute the the inner product between two $n$-qubit quantum states, namely $\\langle\\phi|\\psi\\rangle$, which is in general a complex number. One can get $|\\langle\\phi|\\psi\\rangle|^2$ through thte SWAP test for multiple qubits, but this is not really the inner product as the information of the real and imaginary parts are lost. I came across this , which claims that the task can be done by simply using CZ gates. I'm not sure if I am mistaken, but it seems to me that such a circuit works for computational basis states, but not for general quantum states. Could somebody help me confirm if this is actually the case? If the above algorithm doesn't work for general quantum states, what algorithm would you suggest?", "Why is fundamental group insufficient to classify manifolds? I have heard that some issues in group theory prevent classifying all manifolds upto homotopy using the fundamental group invariant. Does anyone know what are those issues? Thanks, K.", "How do people come up with difficult math Olympiad questions?", "Node only partially rendered near edge of plot I'm trying to draw a relatively simple chart of a number line, and when one of the nodes is too close to the edge of the plot, it gets cut off. The code: \\documentclass{article} \\usepackage{natbib} \\usepackage{graphicx} \\usepackage{pgfplots} \\begin{document} \\begin{tikzpicture} \\begin{axis}[ width=\\columnwidth, axis y line=none, axis lines=left, axis line style={-}, xmin=0, xmax=1, ymin=0, ymax=1, xlabel=$\\mu$, scatter/classes={o={mark=*}}, restrict y to domain=0:1, xtick={0,1} ] \\draw[ultra thin] (axis cs:0, 0) -- (axis cs:0,.05); \\draw[ultra thin] (axis cs:.4, 0) -- (axis cs:.4,.05); \\node[coordinate,label=above:{$B$}] at (axis cs:0.0,0.05) {}; \\node[coordinate,label=above:{$A$}] at (axis cs:0.4,0.05) {}; \\node[coordinate,label=above:{$b$}] at (axis cs:0.2,0.02) {}; \\node[coordinate,label=above:{$a$}] at (axis cs:0.7,0.02) {}; \\end{axis}; \\end{tikzpicture} \\end{document} The Result: How do I get the B to fully render?", "String comparison in Python: is vs. ==", "The binomial expansion: $$(x+y)^{n} = \\sum_{k=0}^{n} \\binom{n}{k} x^k y^{n-k}$$ The General Leibniz rule (used as a generalization of the product rule for derivatives): $$(fg)^{(n)} = \\sum_{k=0}^{n} \\binom{n}{k} f^{(k)} g^{(n-k)}$$ Both formulas can be obtained simply by induction; Newton's binomial also has a combinatorial proof . It's striking how these formulas are similar; is there a possible connection between them? I was thinking that maybe the General Leibniz rule could be obtained using a combinatorial argument as well (hence the binomial coefficients)...", "Installing PHP 5.3 in Ubuntu 14.04 I've just installed Ubuntu 14.04 and am trying to install php 5.3. But when I run apt-get install php5 it's installing php 5.5.9-1ubuntu4. I need to use php 5.3 in the system because the application I'm working on is built with php 5.3. How can I achieve this?", "Open existing file, append a single line", "What longest time ever was achieved at holding light in a closed volume? For what longest possible time it was possible to hold light in a closed volume with mirrored walls? I would be most interested for results with empty volume but results with solid-state volume may be also interesting.", "Does the plastic cap on a Presta valve serve any purpose once fitted to a rim? I can see the use of the valve cap on a Presta valve when the tube is still packaged (it obviously stops the valve puncturing the tube), but does it do anything except look pretty (or not) once you've fitted the tube to a rim? I've kept them on out of habit, because I've had problems with sticking Schrader valves in the past when I've lost the caps and dirt/grime has got in there - but the design of Presta valves suggests to me that they wouldn't suffer this fate. Given that I really need to , is replacing this cap something I can leave out of my daily chores?", "How do I parse an ISO 8601-formatted date?", "Using customized Coordinate System in ArcGIS Desktop?", "Find unique rows in numpy.array", "Validate inputs that are not inside a form with jQuery Validation plugin How can I validate some inputs that are not inside a form tag? All the samples I found have a form tag, but I want to validate some inputs that are not inside a form.", "How do I change my Chrome language back to English?", "Whenever I boot Ubuntu, I get a message that it cannot mount my windows partition, and I can choose to either wait, skip or manually mount. When I try to enter my Windows partition through Nautilus I get a message saying that this partition is hibernated and that I need to enter the file system and properly close it, something I have done with no problem so I don't know why this happens. Here's my partition table, if any more data is needed please let me know. Device Boot Start End Blocks Id System /dev/sda1 2048 20000767 9999360 83 Linux /dev/sda2 20002814 478001151 228999169 5 Extended /dev/sda3 * 478001152 622532607 72265728 7 HPFS/NTFS/exFAT /dev/sda4 622532608 625141759 1304576 82 Linux swap / Solaris /dev/sda5 20002816 478001151 228999168 83 Linux", "Ubuntu won't boot because of lvmetad I've followed this tutorial to install Ubuntu 15.10: After restarting my computer I got to the grub menu and chose Ubuntu. Shortly after that I got this error: /run/lvm/lvmetad.socket: connect failed: No such file or directory WARNING: Failed to connect to lvmetad. Falling back to internal scanning. These messages keep adding up on a black screen every second. After a while, I get access to the initramfs ash console. what am I doing wrong?" ]

[ "When is the image of a linear operator (between Banach spaces) closed?", "Why “which” returns none on some commands I can run? I used which to tell the location of a runnable file. For example, which pwd returns /bin/pwd. However, I found which alias or which compgen etc returns nothing. What are commands like alias? Aren't they executable files on my Linux? I am using bash 4.3 on Ubuntu.", "Conditional Rendering inside Visualforce pages", "How can I save application settings in a Windows Forms application?", "Can I run my CPU at 100% usage for a long time? I have a Dell XPS 15 9570, 32 GB ram, 2.2 ghz and 6 cores. When i use an application (The parsim command on MATLAB) () then my fan starts running fast , during this my PC doesn't seem to be heating but it never got this noisy in the past so it got me worried. In my task manager , the CPU usage shows 100% when this application is running. Is it a problem for the life of laptop, if I run the PC at CPU 100% for like 4 hours in a day? Do I need to be worried about the noisy fan during the application?", "Movie where a guy is sent to a sandy planet where time moves really fast but slow to the outside observer All I remember is the guy was sent to a planet to test something or he did something illegal, and time moved really fast on the planet but slow to the outside world. He had to fix something to leave the planet I think. His dad was also dying and he checked how many days he had left every day, but in the end his dad didn't actually die as time was fast. It took place on a sandy planet.", "How do I write a URL in Markdown on Stack Exchange?", "Another layman blackhole question, pulling one end of a string out from behind the event horizon No long explanation is needed, What would happen if I were to allow one end of a rope to fall past the event horizon of a black hole while I held the other end? Would I be able to pull it out? Would the rope feel extremely (infinitely?) heavy?", "I'm writing code to do Xml serialization. With below function. public static string SerializeToXml(object obj) { XmlSerializer serializer = new XmlSerializer(obj.GetType()); using (StringWriter writer = new StringWriter()) { serializer.Serialize(writer, obj); return writer.ToString(); } } If the argument is a instance of class without parameterless constructor, it will throw a exception. Unhandled Exception: System.InvalidOperationException: CSharpConsole.Foo cannot be serialized because it does not have a parameterless constructor. at System.Xml.Serialization.TypeDesc.CheckSupported() at System.Xml.Serialization.TypeScope.GetTypeDesc(Type type, MemberInfo sourc e, Boolean directReference, Boolean throwOnError) at System.Xml.Serialization.ModelScope.GetTypeModel(Type type, Boolean direct Reference) at System.Xml.Serialization.XmlReflectionImporter.ImportTypeMapping(Type type , XmlRootAttribute root, String defaultNamespace) at System.Xml.Serialization.XmlSerializer..ctor(Type type, String defaultName space) at System.Xml.Serialization.XmlSerializer..ctor(Type type) Why must there be a parameterless constructor in order to allow xml serialization to succeed? EDIT: thanks for cfeduke's answer. The parameterless constructor can be private or internal.", "Is there a word for “not greedy”? The antonym of “greedy” is “generous”. Is there a word for “not greedy” (one who is content with what he has)?", "has been solved, in XeTeX, by this code: \\def\\kright#1{\\leavevmode #1\\kern-\\XeTeXglyphbounds3 \\the\\XeTeXcharglyph`#1 } \\def\\kleft#1{\\leavevmode \\kern-\\XeTeXglyphbounds1 \\the\\XeTeXcharglyph`#1 #1} which allows me to align text more precisely to the ink by accessing the side-bearing measurements (\\XeTeXglyphbounds1 and 3). This XeTeX dependency is currently the only thing stopping me from moving to LuaTeX (mainly for microtype). Is an equivalent function available in LuaTeX, or planned? After reading a bit more on microtype, could the equivalent effect be achieved by an appropriately-tailored set of character protrusions? That way, my move to LuaTeX might be a lot simpler.", "Function is Continuous When Restricted to Closed Sets Which Cover the Space Suppose that $\\{A_i\\}$ is a finite collection of closed sets in $X$ such that $X = \\bigcup A_i$, and $f : X \\to Y$ restricted to each $A_i$ is continuous. Then $f$ is continuous. Okay. The base case ($n=2$) is just the pasting lemma. I am having a little trouble with the inductive case, specifically with what the hypothesis is and how to deal with continuity with respect to subspaces. I believe the inductive hypothesis is to assume that any function over a topological space that is the union of $n-1$ closed sets such that the function restricted to each of these $n-1$ closed set is continuous must be continuous over the whole space. Then I assume I have a topological space $X = \\bigcup_{i=1}^n A_i$, where each $A_i$ is closed, and a function $f : X \\to Y$ such that $f|_{A_i}$ is continuous for each $i$. Thus $X = \\bigcup_{i=1}^{n-1} A_i \\cup A_n$, where $C = \\bigcup_{i=1}^{n-1} A_i$ is closed since it is a finite union of closed sets. If I can show $f|_C$ is continuous, then I simply apply the pasting lemma to finish the problem. Give $C$ the subspace topology, and notice that each $A_i$ is closed in $C$. Thus we have a topological space $C$ that is the union of $n-1$ closed. But do I still have continuity $f$ restricted to $A_i$ since I am no longer considering them subspaces of $X$ but of $C$? When one says $f|_{A_i}$ is continuous, is one saying that $f$ is continuous when restricted to $A_i$ and $A_i$ is given the subspace topology? EDIT: I think I figured out the lemma I need. Claim: Let $A$ and $C$ be subspaces of $X$ such that $A \\subseteq C$. Topologize $C$ with subspace topology with respect to $X$. Then the subspace topology on $A$ as a subspace of $X$ (call it $\\tau_X$) is the same as the subspace topology of $A$ as a subspace of $C$ (call it $\\tau_C$). Proof: Let $U$ be open in $X$. Then $A \\cap U$ is some open set in $A$ as a subspace of $X$. Since $C$ is a subspace of $X$, $C \\cap U$ is open in $C$ as a subspace of $X$. Then $A \\cap (C \\cap U) = (A \\cap C) \\cap U = A \\cap U$ is open in $A$ as a subspace of $C$, thereby proving $\\tau_X \\subseteq \\tau_C$. Now let $O$ be some open set in $C$ as a subspace of $X$. Then $A \\cap O$ is some open subset of $A$ as a subspace of $C$. But $O = C \\cap U$ for some open set in $X$. Therefore $A \\cap O = A \\cap (C \\cap U)= A \\cap U$, which is also open in $A$ as a subspace of $X$. Hence $\\tau_C \\subseteq \\tau_X$ Kind of obvious. But it was hard to spot the need for this lemma when I was considering subspace of subspaces and continuous functions, etc. Am I right in thinking this is the lemma I need?", "Energy-Momentum Tensor in QFT vs. GR What is the correspondence between the conserved canonical energy-momentum tensor, which is $$ T^{\\mu\\nu}_{can} := \\sum_{i=1}^N\\frac{\\delta\\mathcal{L}_{Matter}}{\\delta(\\partial_\\mu f_i)}\\partial^\\nu f_i - \\eta^{\\mu\\nu}\\mathcal{L}$$ (the four conserved Noether currents corresponding to four possible spacetime translations) where $\\{f_i\\}_{i=1}^N$ are the $N$ matter fields in the theory, and we assume $f_i\\mapsto\\alpha^\\nu\\partial_\\nu f_i$ for translations, and stress-energy tensor from the Einstein-Hilbert action, which is: $$ T_{\\mu\\nu}\\equiv-\\frac{2}{\\sqrt{-g}}\\frac{\\delta\\mathcal{L}_{Matter}}{\\delta g^{\\mu\\nu}} $$ In particular, how do you get that the two are equal (are they?) for Minkowski space, for which there is no variation in the metric?", "How can I change the colors of lightning-button? I tried doing this in my css: .my-button { background-color: #14a6bc; color: #ffffff; } and applying that class to my &lt;lightning-button&gt; and removing the variant but I still get the base colors? I am trying to use these examples:", "Significance of assumption in competition inequality questions Refer to the problem below (IMO 2009 Shortlist) Let $a, b, c$ be positive real numbers such that $$\\frac{1}{a} + \\frac{1}{b} + \\frac{1}{c} = a + b+ c$$ Prove that $$\\frac{1}{(2a+b+c)^2} + \\frac{1}{(2a+b+c)^2} + \\frac{1}{(2a+b+c)^2} \\leqslant \\frac{3}{16} $$ In the solution given by the (Pg 16), it states that Without loss of generality, we choose $$a +b+c = 1$$. Thus, the problem becomes $$ \\frac{1}{(1 + a)^2} + \\frac{1}{(1 + b)^2} +\\frac{1}{(1 + b)^2} \\leqslant \\frac{3}{16}(\\frac{1}{a} + \\frac{1}{b} + \\frac{1}{c})$$ Applying Jensen’s inequality to the function $$f(x) = \\frac{x}{ (1+ x)^2}$$ ,which is concave for $0 ≤ x ≤ 2$ and increasing for $0 ≤ x ≤ 1$, we obtain $$α \\frac{a}{(1 + a)^2} + β \\frac{b}{(1 + b)^2} + γ \\frac{c}{(1 + c)^2} \\leqslant (α + β + γ) \\frac{A}{(1 + A)^2}$$ , where $A =\\frac{αa + βb + γc}{α + β + γ}.$ Choosing $α = \\frac{1}{a} , β =\\frac{1}{b},$ and $γ = \\frac{1}{c}$ , we can apply the harmonic-arithmetic-mean inequality $$A =\\frac{3}{\\frac{1}{a} + \\frac{1}{b} + \\frac{1}{c}} ≤ \\frac{a + b + c }{3} = \\frac{1}{3} &lt; 1$$ Finally we prove: $$ \\frac{1}{(1 + a)^2} + \\frac{1}{(1 + b)^2} +\\frac{1}{(1 + b)^2} \\leqslant ( \\frac{1}{a} + \\frac{1}{b} + \\frac{1}{c}) \\frac{A}{(1 + A)^2} \\leqslant ( \\frac{1}{a} + \\frac{1}{b} + \\frac{1}{c})\\frac{A}{(1 + \\frac{1}{3})^2} = \\frac{3}{16}(\\frac{1}{a} + \\frac{1}{b} + \\frac{1}{c}) $$ However, (Pg 4) differs by having $a +b+c=3$ and setting $f(x) = \\frac{1}{16x} - \\frac{1}{(x+3)^2}$ and allowing Jensen to resolve the rest. The questions are as follows; How do you choose before hand which $a + b+ c =$ to choose? Why particularly does the assumption differ between the 2 solutions? How does one know before hand the choosing of $α = \\frac{1}{a} , β =\\frac{1}{b},$ and $γ = \\frac{1}{c}$? Where and how did $A =\\frac{αa + βb + γc}{α + β + γ}$ come from? Any help would be much appreciated.", "How to create a grain / noise effect in Adobe Illustrator I want to create a noise effect using Adobe Illustrator. Inside the hexagonal shape there is some kind of texture effect, I don't know what the name of this effect is: How can I create such an effect in Adobe Illustrator? or is it created using Photoshop?", "How can I adjust the mouse scroll speed?", "Following a global preference for , as of now, the preferences for enabling keyboard shortcuts and disabling the fixed topbar are network-wide* as well. If you had either checked off on any site in the network, that setting has been preserved and applied to the whole network for your account already. Future changes will also apply to all* Q&amp;A sites. Find them in their usual spot as previously on the pages. * With the exception of , which will support the fixed topbar after the .", "Is there a method to export the URLs of the open tabs of a Firefox window? If I have a Firefox window open that contains 10 tabs, is there a way in Firefox or by a plug-in to get the URLs of those 10 tabs as a text file or some other format? Right now if I want to do this I need to copy the URL of tab A, paste it somewhere, move to tab B, and repeat. I could also bookmark all the tabs into a folder and export that, but that seems like such a hassle. If there is no such method, could someone point me to some documents that describe the basics of writing a Firefox plug-in. I am willing to write this myself if there is no \"standard\" way.", "Why is Main method private?" ]

[ "How can I calculate magnification ratio I get by reversing a lens? I am looking for a way to mathematically determine the maximum magnification ratio that is possible/practical to achieve by reverse mounting a non-macro lens, prior to purchasing the lens. See related questions:", "Expectation of Exit Time of Brownian Motion from Interval I am trying to solve the following: Let $W_t$ be a brownian motion and $a,b &gt;0.$ Define $\\tau$ to be the exit time of $W_t$ from $[-a,b]$, that is $$\\tau = \\inf\\{t \\ge 0\\ :\\ W_{t}(\\omega) \\notin [-a,b]\\}.$$ Show that $\\tau$ is integrable and compute $\\mathbb{E}(\\tau)$. I have seen this stated without proof multiple places that $\\mathbb{E}(\\tau)=ab.$ What is the logical argument that backs up this statement? How are we guaranteed $\\tau$ is integrable?", "Pretty self descriptive, without being able to view the source of the noise how can we tell the difference between a sound in front of us and a sound behind us if pitch, volume and distance are all the same. Also assume that it is not biased to one side more than the other, e.g its not to your left or right but directly in front or behind. I'm interested in knowing if it is a part of the ear that makes this distinction, or a function of the brain.", "Java equivalent of unsigned long long? In C++, I enjoyed having access to a 64 bit unsigned integer, via unsigned long long int, or via uint64_t. Now, in Java longs are 64 bits, I know. However, they are signed. Is there an unsigned long (long) available as a Java primitive? How do I use it?", "What is so special about speed of light in vacuum?", "1. Why is the wave function complex? I've collected some layman explanations but they are incomplete and unsatisfactory. However in the book by Merzbacher in the initial few pages he provides an explanation that I need some help with: that the de Broglie wavelength and the wavelength of an elastic wave do not show similar properties under a Galilean transformation. He basically says that both are equivalent under a gauge transform and also, separately by Lorentz transforms. This, accompanied with the observation that $\\psi$ is not observable, so there is no \"reason for it being real\". Can someone give me an intuitive prelude by what is a gauge transform and why does it give the same result as a Lorentz tranformation in a non-relativistic setting? And eventually how in this \"grand scheme\" the complex nature of the wave function becomes evident.. in a way that a dummy like me can understand. 2. A wavefunction can be thought of as a scalar field (has a scalar value in every point ($r,t$) given by $\\psi:\\mathbb{R^3}\\times \\mathbb{R}\\rightarrow \\mathbb{C}$ and also as a ray in Hilbert space (a vector). How are these two perspectives the same (this is possibly something elementary that I am missing out, or getting confused by definitions and terminology, if that is the case I am desperate for help ;) 3. One way I have thought about the above question is that the wave function can be equivalently written in $\\psi:\\mathbb{R^3}\\times \\mathbb{R}\\rightarrow \\mathbb{R}^2 $ i.e, Since a wave function is complex, the Schroedinger equation could in principle be written equivalently as coupled differential equations in two real functions which staisfy the Cauchy-Riemann conditions. ie, if $$\\psi(x,t) = u(x,t) + i v(x,t)$$ and $u_x=v_t$ ; $u_t = -v_x$ and we get $$\\hbar \\partial_t u = -\\frac{\\hbar^2}{2m} \\partial_x^2v + V v$$ $$\\hbar \\partial_t v = \\frac{\\hbar^2}{2m} \\partial_x^2u - V u$$ (..in 1-D) If this is correct what are the interpretations of the $u,v$.. and why isn't it useful. (I am assuming that physical problems always have an analytic $\\psi(r,t)$).", "Legend inconsistent in QGIS map print layout After I did styling my vector data set to be classified by graduated circle and categorized by type, it appears beautifully consistent in the map canvas as shown below: But when I create a print map layout and after adding the map, I add the legend and it come out ugly inconsistent like this: So, I would like to ask for help to make the legend in the map print layout consistent as the legend shown in layer panel. I use the latest version QGIS 3.10.2 64bit.", "Finding the left and right cosets of H = {(1), (12), (34), (12) ○ (34)} in S4 I have an exercise where I am supposed to find the left and right cosets of H = {(1), (12), (34), (12) ○ (34)} in S4. But how do I generate the cosets? As I have understood it you are supposed to pick a number that is not in the set H and multiply it with every number in H. But this does not exactly give the right answer. I would really appreciate it if someone gave an easy to understand explanation of how to generate the left and right cosets.", "Every subsequence of $x_n$ has a further subsequence which converges to $x$. Then the sequence $x_n$ converges to $x$.", "I just know that ls -t and ls -f give different sorting of files and subdirectories under a directory. What are the differences between timestamp, modification time, and created time of a file? How to get and change these kinds of information by commands? In terms of what kind of information do people say a file is \"newer\" than the other? What kinds of information's change will not make the file different? For example, I saw someone wrote: By default, the rsync program only looks to see if the files are different in size and timestamp. It doesn't care which file is newer, if it is different, it gets overwritten. You can pass the '--update' flag to rsync which will cause it to skip files on the destination if they are newer than the file on the source, but only so long as they are the same type of file. What this means is that if, for example, the source file is a regular file and the destination is a symlink, the destination file will be overwritten, regardless of timestamp. On a side note, does the file type here mean only regular file and simlink, not the type such as pdf, jpg, htm, txt etc?", "How can I add some html to my Mail.app signature? I want to add my company logo and and some juice to my contact information in the signature part in Mail.app. How can I do that with little or no efforts?", "Annotation Scaling I made a map with annotations in QGIS 3.0. This is how it looks like in the layout view: If I print the map as PDF, one would expect to get the PDF to be WYSIWYG, right? However, it looks like this (it's about half the size): Is there a way to influence the the scaling of the Annoations? I already tried to play with the Scale and Magnifier in the map view. I also tried to change the Scale in the map item. The strange thing is, I believe it worked a few days ago. But today I installed QGIS 3.0 on a new PC and it showed the same behaviour...", "Why are doctors addressed as Mr. in the UK? In the US most physicians, surgeons and dentists are addressed as \"doctor\". Very few other professionals receive the same title. In the UK, however, surgeons and dentists seem to prefer to be referred to as Mr. If that is true, why? And who is addressed as Dr. in the UK? Those who hold doctoral degrees only?", "How to troubleshoot booting to a black screen on VirtualBox I was using 13.04 as a guest OS on my VirtualBox 14.2.18. Host is Windows 8. After upgrade to 13.10 Ubuntu does not start. I can see a black screen and blinking cursor. I am pretty new to Ubuntu. I suspect a problem with graphics drivers. I can access tty and all files (/home) are there.", "Is SSIS subject to the maximum memory limitations for SQL Server 2012 Standard edition? If I have a server with 128GB RAM and I allocate 64GB of RAM to SQL Server does SSIS utilise this memory or does it utilise the memory that is available to the OS? I am assuming it utilises the remaining memory left to the OS since there is no settings for memory consumption and it runs as a separate service. If anyone has any information on the available memory that should be left for SSIS to consume I would appreciate the help.", "Can I backup my entire Ubuntu installation to ISO DVD?", "Prove $2^b-1$ does not divide $2^a + 1$ for $a,b>2$ I'm trying to prove $2^b-1$ does not divide $2^a + 1$ for $a,b&gt;2$. Can someone give a hint in the right direction for this?", "Meta sites in \"Your Communities\" display different reputation", "Will an iOS reinstall make a jailbroken iOS device \"unjailbroken\" and “supported by Apple” again? Will an Work on any jailbroken-iPhone and Make a jailbroken-iPhone \"unjailbroken\"? Make a jailbroken-iPhone \"supported by Apple\"? Similarly, does such an iOS reinstall reset the iPhone (jailbroken or not) back to a \"clean, factory default\" state? My near-term purpose: I have an iPhone 4S running iOS 5.1 I'd like to jailbreak to at least install better Google Voice integration like .", "Move item to folder when added/edited (SP2013 or O365) How to move item to folder automatically when it has been added or edited in a library? The folder is in the same library. The correct folder will be defined by metadata. This should happen automatically when the item has been added or edited. The listitem Id should be preserved. No server-side code should be deployed. Can this be done using workflows (SP2010/SP2013)? If not then what would be the other options?" ]

[ "When I've worked a bit with my source code, I did my usual thing commit and then I pushed to a remote repository. But then I noticed I forgot to organize my imports in the source code. So I do the amend command to replace the previous commit: &gt; git commit --amend Unfortunately the commit can't be pushed back to the repository. It is rejected like this: &gt; git push origin To //my.remote.repo.com/stuff.git/ ! [rejected] master -&gt; master (non-fast forward) error: failed to push some refs to '//my.remote.repo.com/stuff.git/' What should I do? (I can access the remote repository.)", "Solve $[2^{(2^{403})}] = [a]$ in $\\mathbb Z_{23}$ where $0 \\le a < 23$. Solve $[2^{(2^{403})}] = [a]$ in $\\mathbb Z_{23}$ where $0 \\le a &lt; 23$. I've tried to combine corollaries of Fermat's little theorem and various other methods to solve this, but have always been stuck.", "Icon for pinned tabs in Safari? It would be nice to for . As it is, SE kind of stands out (in a not cool way):", "What is meant by \"obfuscate by pretending\"? I came accross the following sentence: \"Politicians obfuscate by pretending that the world would be the same if it weren't for the Cold War.\" What is the meaning of obfuscate by pretending and how does it relate to the rest of the sentence? The way I understood it: politicans are aware that the world would not be the same if it weren't for the Cold War, but are (due to unknown or suspected reasons) not willing to admit this and therefore pretend otherwise.", "For example: The word rarely turns up outside of those contexts. The word turns up rarely outside of those contexts. Which one is correct and why?", "I was surprised to only recently notice that An object of any density can be large enough to fall within its own Schwarzschild radius. Of course! It turns out that supermassive black holes at galactic centers can have an average density of less than water's. Somehow I always operated under the assumption that black holes of any size had to be superdense objects by everyday standards. Compare the Earth to collapsing into a mere 9mm marble retaining the same mass, in order for the escape velocity at the surface to finally reach that of light. Or Mt. Everest packed into one nanometer. Reading on about this , it increases proportionally with total mass. Assuming matter is accumulated at a steady density into a spherical volume, the volume's radius will only \"grow\" at a cube root of the total volume and be quickly outpaced by its own gravitational radius. Question: For an object the , what would have to be its diameter for it to qualify as a black hole (from an external point of view)? Would this not imply by definition that: The Earth, Solar system and Milky Way are conceivably inside this black hole? Black holes can be nested/be contained within larger ones? Whether something is a black hole or not is actually a matter of perspective/where the observer is, inside or outside?", "Story about building up speed leading to increased quality of life It's a story I read in 2 or 3 parts in a Greek sci-fi magazine called 9 around 2004 (give or take a few years), but it may be a bit older than that. This is what I remember (and I hope it's all accurate): The protagonist used to travel a lot, mainly using high speed media like aircraft. It was established in the story that as he traveled more frequently and with more speed, he would gradually cross over towards (sort of) higher planes of existence (and that everyone in the setting could do the same, although most people simply didn't bother). These higher planes of existence were apparently still Earth, but the environments and the inhabitants were increasingly more alien and life in them was increasingly luxurious. As far as I recall, the protagonist's goal was to reach those higher levels (either for the luxury or for some other reason I can't recall). If he failed to maintain his \"speed\" for too long, he would fall back to lower planes of existence, with more familiar characteristics and significantly lower quality of life. His wife had died some time ago and her grave was apparently in the lower planes. He did visit her once near the end of the story, before starting to build up \"speed\" again. I don't happen to know the original language of the story because what I read was a version translated into Greek.", "I am running centos 5.8 with cpanel. Lately I am getting reports that my swap is full , but there is a lot of free memory to use. top - 10:33:43 up 133 days, 17:00, 1 user, load average: 0.05, 0.03, 0.05 Tasks: 170 total, 1 running, 169 sleeping, 0 stopped, 0 zombie Cpu(s): 2.1%us, 0.5%sy, 0.0%ni, 97.2%id, 0.0%wa, 0.0%hi, 0.2%si, 0.0%st Mem: 24726100k total, 8255368k used, 16470732k free, 599560k buffers Swap: 1046520k total, 984740k used, 61780k free, 3641828k cached How do I solve this? The unused ram memory should be used instead of the swap. Or should I increase the swap ( and how do I do that ? ). Thanks", "I am struggling to understand zero inflated distributions. What are they? What's the point? If I have data with many zeroes, then I could fit a logistic regression first calculate the probability of zeroes, and then I could remove all the zeroes, and then fit a regular regression using my choice of distribution (poisson e.g.). Then somebody told me \"hey, use a zero inflated distribution\", but looking it up, it does not seem to do anything differently than what I suggested above? It has a regular parameter $\\mu$, and then another parameter $p$ to model the probability of zero? It just does both things at the same time no?", "I am a platform diver. I am trying to figure out how deep in the water I go depending on which platform I dive from. The platforms are 1m, 3m, 5m, 7.5m and 10m above the water surface. By ignoring air resistance (we assume that I do not do any tricks) I can easily compute the energy that my 90 kg body has when it is hitting the water: E = mgh = 0.5mv^2 My problem is to find the deceleration in water and thus how deep my feet will go into the water before coming to a halt. We can assume that I stand straight and fall straight down and have a height of 190cm. How do I compute that?", "Command line move file with long directory path without repeating directory path Is there any way of executing a mv command without typing the full path in the second argument? Example: mv my/file/that/has/a/really/long/path/foo.bar some_magic_operator_that_means_the_same_directory/foo.baz", "IEEEtran - How to include ORCID in TeX/PDF with PdfLatex This question led to a new package: I would like to display the ORCID id in an author list in an IEEEtran pdf, like that: Is there a standard way to include it in an IEEEtran article with PdfLaTeX? I used two approaches from , but I failed. One is to insert the ORCID icon in the author list. I used the blow code: \\author{Ali Al-Obaidi \\href{https://orcid.org/0000-0000-0000-0000}{\\includegraphics[scale=1]{figures/orcid_16x16.png}}} where orchid_16x16.png is provided in the link . But the result is that the icon is not clear enough, even I replaced it with a different size. The other approach is to use the package, like that: \\usepackage{academicons} \\definecolor{orcidlogocol}{HTML}{A6CE39} \\author{AAA \\href{https://orcid.org/0000-0000-0000-0000}{\\textcolor{orcidlogocol}{\\aiOrcid}}} However, the result is like that: And I also got two errors: &quot;Latex Error: Encoding scheme 'TU' unknown&quot; and &quot;Bad character code (59865)&quot;. In the latest academicons.sty (see ), academicons use the font TU. However, it seems that the compiler PdfLateX cannot support this font. Thus, is there anyone that knows a standard way to include it in an IEEEtran article with PdfLaTeX? Please help me.", "$\\sum_{n=1}^\\infty\\frac{z^n}{n}$ does not converge uniformly on $\\mathbb{D}$.", "Suspending with root on USB I have a laptop running Ubuntu 14.04 from a root file system on USB storage. This is not working well, because after wake up from suspend, ext4 will frequently try to write to the root file system before USB is ready. Here is what I see in the kernel log when this happens, notice how I get a bunch of I/O errors on sda1, and then one second later the USB storage drive is finally detected by the kernel. [ 2826.517419] wlan0: associated [ 2826.517452] IPv6: ADDRCONF(NETDEV_CHANGE): wlan0: link becomes ready [ 2827.575371] EXT4-fs warning (device sda1): ext4_end_bio:317: I/O error -5 writing to inode 1733735 (offset 0 size 0 starting block 12629950) [ 2827.575380] Buffer I/O error on device sda1, logical block 12629694 [ 2827.575400] EXT4-fs warning (device sda1): ext4_end_bio:317: I/O error -5 writing to inode 3148603 (offset 0 size 8192 starting block 12844470) [ 2827.575404] Buffer I/O error on device sda1, logical block 12844212 [ 2827.575411] Buffer I/O error on device sda1, logical block 12844213 [ 2827.575448] EXT4-fs warning (device sda1): ext4_end_bio:317: I/O error -5 writing to inode 3015015 (offset 0 size 90112 starting block 6588832) [ 2827.575453] Buffer I/O error on device sda1, logical block 6588576 [ 2827.575461] Buffer I/O error on device sda1, logical block 6588577 [ 2827.575465] Buffer I/O error on device sda1, logical block 6588578 [ 2827.575469] Buffer I/O error on device sda1, logical block 6588579 [ 2827.575473] Buffer I/O error on device sda1, logical block 6588580 [ 2827.575477] Buffer I/O error on device sda1, logical block 6588581 [ 2827.575481] Buffer I/O error on device sda1, logical block 6588582 [ 2828.857284] sd 0:0:0:0: [sda] No Caching mode page found [ 2828.857293] sd 0:0:0:0: [sda] Assuming drive cache: write through At first there is no visible indication outside of the kernel log, that the problem has triggered, but if I let Ubuntu stay running beyond this point, then the file system will get errors and eventually switch to read only mode. At that point I have to reboot into recovery mode and run fsck.ext4 manually from a root shell in order to repair the file system. Is there some setting I can change such that access to the root device after waking from suspend can be delayed until the USB drive is ready?", "Is there any way to increase the drop rate of items? Some items in Terraria drop only very rarely from certain enemies. It's a pain having to farm so many enemies to try to get these rare items. Is there any way to make them drop more often?", "Can it be assumed a evaluation order of the function parameters when calling it in C ? According to the following program, it seems that there is not a particular order when I executed it. #include &lt;stdio.h&gt; int main() { int a[] = {1, 2, 3}; int * pa; pa = &amp;a[0]; printf(\"a[0] = %d\\ta[1] = %d\\ta[2] = %d\\n\",*(pa), *(pa++),*(++pa)); /* Result: a[0] = 3 a[1] = 2 a[2] = 2 */ pa = &amp;a[0]; printf(\"a[0] = %d\\ta[1] = %d\\ta[2] = %d\\n\",*(pa++),*(pa),*(++pa)); /* Result: a[0] = 2 a[1] = 2 a[2] = 2 */ pa = &amp;a[0]; printf(\"a[0] = %d\\ta[1] = %d\\ta[2] = %d\\n\",*(pa++),*(++pa), *(pa)); /* a[0] = 2 a[1] = 2 a[2] = 1 */ }", "'find' utility does not output all files when using wildcards", "Default poster size What is the typical size for a conference poster? Is it \"ask the organizers\", or can I safely assume that I'll get a default size, and that there will be enough space to hang it at the poster session?", "Mouse sensitivity in 14.04 dissapeared If I go to \"Settings -> Mouse &amp; Touchpad\" in Ubuntu 14.04 all the options are gone! How can I bring them back?", "Rotate group of objects over an edge" ]

[ "Two blue arrows at top right of icons On some icons I am seeing a two blue arrows at the top the right pointing towards each other. I first noticed it on the icons on folders which I archived which happened randomly. I archived the folder and the text went blue as expected, then when I went to the folder again the text was black and the folder icon has these arrows. When I just recently installed Office 2007, I noticed the same arrows on the icons for the programs. OS: Windows 10 Pro 64-bit (the latest update: 1115) Application: Microsoft Office 2007 suite and file explorer", "Is it possible to assign numbers generated in an Error-Message?", "When does Thread.CurrentThread.Join() make sense?", "I'm in the market for a new Smartphone. Except for iPhone's, I'm new in the field and probably have some misconceptions. My first choice was the Google Nexus S, but I was offered a great deal on the Samsung S Galaxy II (i9100). The only issue is that I read that it came with an \"enhanced\" version of Android. Being familiar with PC's, I know that these enhancements are almost always bloatware: I always do a clean install of Windows to get rid of it. My question is fairly simple: is this possible to use the stock Google Android OS on the Samsung S Galaxy II (i9100)? That was the killer feature of the Nexus S for me: coming directly from Google, easily upgradable. Would that be possible and if yes, how? Thank you for enlightening me.", "Forgotten iOS Restrictions Password/Passcode", "Cannot move file to trash warning when trying to delete a file in Nautilus I am trying to delete files in Nautilus and every time I try to delete one it always gives me this message: Cannot move file to trash, do you want to delete immediately? Then it gives me several questions. All I want is that when I press Delete in the keyboard, it sends it automatically to the trash can. Not to ask me every time. The problem relates to NTFS partitions, external drives but also include Linux filesystems. What are the reasons for nautilus beeing not able to move to trash?", "If $2^p-1$ is a prime, (thus $p$ is a prime, too) then $p\\mid 2^p-2=\\phi(2^p-1).$ But I find $n\\mid \\phi(2^n-1)$ is always hold, no matter what $n$ is. Such as $4\\mid \\phi(2^4-1)=8.$ If we denote $a_n=\\dfrac{\\phi(2^n-1)}{n}$, then $a_n$ is , but how to prove it is always integer? Thanks in advance!", "Is there a deb package to install Firefox ESR? I would like to have on my system but I would like to install it via apt-get. Is there a special package to install this? Download link would be:", "How to install Wi-Fi driver for Realtek RTL8821CE on Ubuntu 18.04?", "What is \"%AppData%\"?", "The characteristic and minimal polynomial of a companion matrix of a monic polynomial $f \\in \\mathbb F\\left[x\\right]$ in $1$ variable $x$ over a field $\\mathbb F$ plays an important role in understanding the structure of finite dimensional $\\mathbb F[x]$-modules. It is an important fact that the characteristic polynomial and the minimal polynomial of $C(f)$ are both equal to $f$. This can be seen quite easily by induction on the degree of $f$. Does anyone know a different proof of this fact? I would love to see a graph theoretic proof or a non inductive algebraic proof, but I would be happy with anything that makes it seem like more than a coincidence!", "Apple Loops Copyright", "How do you clear a stringstream variable? I've tried several things already, std::stringstream m; m.empty(); m.clear(); both of which don't work.", "Minimum safe spacing between lava and flamable materials? It seems that containing lava in solid glass, stone and iron blocks may not be sufficient to prevent wool from burning, even if the lava is completely encased. After some delay, it seems that fire will jump onto the wool above the iron. Are solid blocks more effective than airspace, or not? If so, Does it matter whether the corner block is filled in? What are the exact rules on distance that I need, and how can I prevent flammable blocks from being eliminated by nearby lava? Bonus: Does a flowing lava block behave differently than a lava source block when it comes to fire creation?", "Why is my attempt at downloading Big Sur failing? I am currently using a MacBook Pro 13&quot; Mid 2018 with Touch Bar. Today macOS Big Sur was released and I tried to download it but it's getting stuck at 484.4 MB. Initially, it shows 16-17 minutes left, but as soon as it reaches 484.4 MB it's stuck and the timer goes till 10 hours! My Wi-Fi is totally stable with a speed of 100 Mbps. I tried to restart my Mac but it still gets stuck. Earlier there were similar issues in the App Store (even now they are). The issue was I was not able to download an app unless I connect to the US VPN. I even contacted support but they were not able to help out. It wasn't a big deal as a VPN could be used. But now even with VPN, it gets stuck.", "Proving that $G$ is a group if $a*x=b$ and $y*a=b$ have solutions.", "Makeindex error when ! used in \\index in align environment See MWE below. The symbol ! in the \\index causes an error. This is only the case in align environments (not in equation). So it seems to have to do something with amsmath. If ! is put in an \\mbox there is no error. But then of course the font size is not adjusted to subindices. Curiously enough, \\index{$C_{K!!}$} (two exclamation marks) doesn't cause any error. \\documentclass{article} \\usepackage{amsmath} \\usepackage{imakeidx} \\makeindex \\begin{document} \\begin{align} y\\index{$C_{K!}$} \\end{align} \\printindex \\end{document} Any solutions suggested?", "I have a file with ANSI colors. test.txt: \\e[0;31mExample\\e[0m I would like to display the content of this file in a terminal, like cat does, but I would like to display the colors as well.", "What is PECS (Producer Extends Consumer Super)?", "Fermat's Last Theorem with negative exponent" ]

[ "Using Vim I often want to replace a block of code with a block that I just yanked. But when I delete the block of code that is to be replaced, that block itself goes into the register which erases the block I just yanked. So I've got in the habit of yanking, then inserting, then deleting what I didn't want, but with large blocks of code this gets messy trying to keep the inserted block and the block to delete separate. So what is the slickest and quickest way to replace text in Vim? is there a way to delete text without putting it into the register? is there a way to say e.g. \"replace next word\" or \"replace up to next paragraph\" or is the best way to somehow use the multi-register feature?", "How does Cantor's diagonal argument work?", "I was told that the Galilean relative velocity rule does not apply to the speed of light. No matter how fast two objects are moving, the speed of light will remain same for both of them. How and why is this possible? Also, why can't anything travel faster than light?", "Usage of \"second/third/fourth ... last\" In German there is a pattern for counting items from the end of a list. The last item is \"das letzte\", the one before is \"das vorletzte\", the one before that is \"das vorvorletzte\" and for each other item there's just another \"vor\" added. While searching for an English translation for the German word \"vorvorvorletzte\" I came across and but none of them showed any usage pattern. Furthermore I didn't find any indication of which variant (\"to\", \"from\", no preposition) is used most nor to what area of the world those translations apply. So I am still wondering: When there are items 1, 2, 3, 4 and 5, how can/will item 2 be called? third from last? fourth from last? anteantepenultimate? fourth-last? fourth to last? the last but three item? the last but four item? Is this a question of dialect/local use?", "Scoring when two triple word squares are covered in one play The word QUAGMIRE is on the board vertically, with the Q on the top row, second column. The next player creates SQUEEZED horizontally, landing the S on the triple word square in the top row, first column, and remaining UEEZED landing to the right of the existing Q, ending with the D on the triple word square in the eighth column. Since two triple word squares are covered in this one placement, how would it be scored? Letters: S: 1 Q: 10 U: 1 E: 1 x 2 (double letter) E: 1 Z: 10 E: 1 D: 1 27 Total for letters. Do you then multiply by 3 for the first triple word square, and then multiply that result by 3? 27 X 3 = 81, 81 X 3 = 243 Bonus for all 7 tiles placed: 243 + 50 = 293", "Javascript mechanism to autoscroll to the bottom of a growing page?", "Gtk skip_taskbar_hint (seen in Glade-ui-Designer) equivalent in Qt With Glade Designer that lets you set up Gtk-Ui's you can check the option that windows are not shown in the launcher. If I take a look at the ui-file generated by Glade, it says &lt;property name=\"skip_taskbar_hint\"&gt;True&lt;/property&gt;. In gtk code this hint is window.set_property('skip-taskbar-hint', True). However I believe that this option is not exclusively Gtk-specific, and want to apply this one on my PyQt4-app. The Ubuntu window manager must be able to receive that hint, otherwise I would see the window of a gtk-application i use (stickynotes-indicator). So there MUST be a way of doing this in Qt or any other language, right? Does anybody know such an option? Python or Qt syntax, doesn't matter!", "ImportError: no module named win32api", "No \\xrightrightarrow[a]{b}?", "How do I change the default wifi network that Ubuntu connects to on startup? There is an unsecured public wifi network in my range, as well as my own home WPA secured wifi that I want to use by default. However, on startup Ubuntu always connects to the unsecured one. Sometimes I forget to reconnect to the other one, which is very dangerous. I am running a default setup of Ubuntu Destkop 11.10 with Gnome 3. I have looked under network settings but I can't find a 'default' option.", "Map preserving intervals but discontinuous", "Dependency is not satisfiable: libtiff4 when trying to install Lightworks on Ubuntu 14.04 I was trying to install Lightworks 11.5.1 (amd64) on Ubuntu 14.04(amd64) but there's a notice: Dependency is not satisfiable: libtiff4. Is there anyway to solve this dependency issue? Thanks in advance.", "How did Luke know where to land on Dagobah?", "Is there a detailed user's documentation for KDE Plasma 5?", "Can the Force be used to fly?", "How to upload LaTeX-generated pdf paper to arXiv without LaTeX sources arXiv is smart enough to detect whether your PDF is generated by LaTeX. If it is, arXiv asks for the sources of the PDF instead of the PDF file itself. This is really annoying and inconvenient. I ask a way to fool the arXiv and avoid PDFs being detected as generated by LaTeX (even if they were indeed). I have tried this: : \"create a pdf from word and then simply insert pages from your article, and delete the word's page\". And it did not work.", "I am a novice user and I am trying to install Oracle Java. The process calls for me to access /usr/local/java, but here is the problem. I get as far as /usr/local, then this is the message I get: leonard@leonard-MT6452:/usr/local$ dir bin etc games include java lib man sbin share src leonard@leonard-MT6452:/usr/local$ cd /java/ bash: cd: /java/: No such file or directory leonard@leonard-MT6452:/usr/local$ rm -r ~/java rm: cannot remove ‘/home/leonard/java’: No such file or directory Help?", "Can't read filenames in save dialog box. Names are too faint I want to click on file to inherit the name for the file being saved. I can't read file names in the dialog box because the color is too faint. This is the same question as That question does not have an answer but I don't have enough points to interact there so I have to post a new question. Edited to add screen shots I tried to calibrate the monitor which no effect and did not change the readability of \"unavailable\" file names. I have added screenshots of previous operating systems to compare: Please tell me how Mojave is not to blame here:", "I took some shots recently and I noticed that I'm getting a lot of little black dots in my images. I cleaned my lens thoroughly with the Nikon camelhair brush and retook the pictures but once again, the dots appear. I'm shooting with a Nikon D7000 and using a starter lens. I've attached an example (notice the black spots on the chairs, on the ceiling, etc).", "\"To work for\" vs. \"to work in\" vs. \"to work at\" Is the preposition in universal in conjunction with the verb ‘to work’ and can it be used with any organizations and businesses? For example: He works as a cook in a local hotel near here. He works in an office in Chicago. She works in a big company. She works in the emergency unit at the hospital. She works in a shoe repair shop. After leaving school, he worked in a restaurant for a year. military hospital. His sister works in a bank. She works in a shoe factory. He works in a steel plant. She works in a gift store on weekends. Ann works in a research institute. When should the prepositions at and for be used? For example: Barbara works at a travel agency. She works at the local supermarket. Now he works for a bank. I work for a small non-profit organization. I’ve never heard: She works for a shoe factory. But with a law firm it’s OK: She works for a law firm. Why?" ]

[ "In Rey's vision, whose voice says \"These are your first steps\"?", "I'm going to install Linux on Lenovo B5400, which contains: 500GB Hybrid SSHD with a 8 GB SSD and 500 GB HDD Designing partitions for my 2 Linux distros was quite easy before, when I had only HDD. I always had: 10GB for Linux distro (mounted as \"/\") 10GB for another distro (again \"/\"; for another distro; for testing purposes or to assure continuity when switching distros) 2GB for swap (used for both distros; no need to separate) 300GB+ for \"/home\" (used for both distros; different usernames eliminates possible conflicts) It's simple, isn't it? I would like to keep this approach, but I know that SSD has its own specificity - it prefers to be read, continuous writing may affect its life span. I don't want to kill SSD in a year, so I would like to move some system partitions to HDD in order to protect SSD. As far as I know /tmp is one of often read&amp;written locations. How much space it needs? What else should be placed on HDD? Or: how to design partitions to achieve exactly the same effect and to keep SSD as safe as possible? I'd be grateful for your help.", "SQL Server 2016 memory optimised table: Precreated files constantly growing I have a memory optimised table in SQL Server 2016, with file durability enabled. The table is only 100MB. SQL Server is constantly creating new files on disk, which start off at a few hundred MB, but then grow constantly until the drive runs out of space then they clear down and the process starts again. The files are growing at about 900MB an hour. Running the SQL below shows that all the space is in Precreated Data - so it's not even actually storing large amounts of data, just allocating space to use later. SELECT state_desc, file_type_desc, COUNT(*) AS [count], SUM(file_size_in_bytes) / 1024 / 1024 AS [on-disk size MB] FROM sys.dm_db_xtp_checkpoint_files GROUP BY state, state_desc, file_type, file_type_desc ORDER BY state, file_type File growth on the file group is set to unlimited, so I'm assuming I can set a value on this and stop it growing, but I can't find anything to say why it's allocating so much space in the first place. The data in the table does change very rapidly (a lot of inserts and deletes as the data is constantly processed, but it the data that isn't Precreated never gets over 4GB. Is there a setting in SQL Server that controls this file precreation? Is it safe to set a limit on the autogrowth for the file group?", "bcmwl-kernel-source broken on kernel: 5.8.0-34-generic", "When to use an offset in a Poisson regression? Does anybody know why offset in a Poisson regression is used? What do you achieve by this?", "HTTP vs HTTPS performance", "How can I make a hexagonal grill? How would I be able to create a grill of sorts found on the front of some computer cases such as this one", "Recovering Crashed Flash drive? So my friend has a USB flash drive that isn't working. I don't know a whole lot about \"recovery\" software so I figured I'd ask you guys. What steps can I try (I have access to a Linux machine as well) to see....if I can get ANYTHING off the flash drive? I've google'd around, but most of the stuff seems for windows.", "Is it true that the light from some galaxies will never reach us? The explanation for that is that the Universe expanding faster than the speed of light. But, if the speed of light is constant in all reference frames, then in the reference frame of a galaxy, light must move at the speed of light and thus it must reach us (?). Could you also explain how is it possible that the Universe is expanding faster than the speed of light if an object can never be observed to move faster than light? (without Doppler effects).", "What is purpose of /etc/shadow and shadow cache files in Linux operating system? What is the purpose of the /etc/shadow file in Linux Operating system? Also, is it same for SUSE clients? There is one shadow cache file is maintained what is purpose of that?", "Cannot change brightness setting using function buttons or using the brightness control bar on HP laptop", "I want to dynamically create a sequence of strings by manipulate an array of elements and create some arithmetic procedure. for name in FIRST SECOND THIRD FOURTH FIFTH; do $name = $(( $6 + 1 )) $name = \"${$name}q;d\" echo \"${$name}\"; printf \"\\n\" done The desire outcome would be the below for $6 equals 0. 1q;d 2q;d 3q;d 4q;d 5q;d But I get this error reel_first_part.sh: line 18: FIRST: command not found reel_first_part.sh: line 19: ${$name}q;d: bad substitution reel_first_part.sh: line 18: FIRST: command not found reel_first_part.sh: line 19: ${$name}q;d: bad substitution reel_first_part.sh: line 18: FIRST: command not found reel_first_part.sh: line 19: ${$name}q;d: bad substitution I guess it's something simple. It used to work when I did something like FIRST=$(( $6 + 1 )) FIRST=\"${FIRST}q;d\"", "Could there be a bit of reputation leakage between the sites, please?", "Multiple Inheritance in C# Since multiple inheritance is bad (it makes the source more complicated) C# does not provide such a pattern directly. But sometimes it would be helpful to have this ability. For instance I'm able to implement the missing multiple inheritance pattern using interfaces and three classes like that: public interface IFirst { void FirstMethod(); } public interface ISecond { void SecondMethod(); } public class First:IFirst { public void FirstMethod() { Console.WriteLine(&quot;First&quot;); } } public class Second:ISecond { public void SecondMethod() { Console.WriteLine(&quot;Second&quot;); } } public class FirstAndSecond: IFirst, ISecond { First first = new First(); Second second = new Second(); public void FirstMethod() { first.FirstMethod(); } public void SecondMethod() { second.SecondMethod(); } } Every time I add a method to one of the interfaces I need to change the class FirstAndSecond as well. Is there a way to inject multiple existing classes into one new class like it is possible in C++? Maybe there is a solution using some kind of code generation? Or it may look like this (imaginary c# syntax): public class FirstAndSecond: IFirst from First, ISecond from Second { } So that there won't be a need to update the class FirstAndSecond when I modify one of the interfaces. EDIT Maybe it would be better to consider a practical example: You have an existing class (e.g. a text based TCP client based on ITextTcpClient) which you do already use at different locations inside your project. Now you feel the need to create a component of your class to be easy accessible for windows forms developers. As far as I know you currently have two ways to do this: Write a new class that is inherited from components and implements the interface of the TextTcpClient class using an instance of the class itself as shown with FirstAndSecond. Write a new class that inherits from TextTcpClient and somehow implements IComponent (haven't actually tried this yet). In both cases you need to do work per method and not per class. Since you know that we will need all the methods of TextTcpClient and Component it would be the easiest solution to just combine those two into one class. To avoid conflicts this may be done by code generation where the result could be altered afterwards but typing this by hand is a pure pain in the ass.", "Please help understanding the difference between force and kinetic energy for an object hitting a wall? If a car hits a wall at a speed of $v$, and an identical car hits a wall at a speed of $2\\,v$, with the kinetic energy equation $E_K = \\frac{1}{2}mv^2$ (the speed goes from $v$ to $0$) the second car will lose 4 times the energy, and therefore cause 4 times the damage, but with the force equation $F = ma$ (the car hits the wall and decelerates), it will hit with 2 times the force, and cause 2 times the damage. How can this be explained?", "I am writing a bash script that needs to know which desktop environment (XFCE, Unity, KDE, LXDE, Mate, Cinnamon, GNOME2, GNOME3,... ) is running. How can I obtain that information?", "How To Set Default Wallpaper As Login Screen Wallpaper [Automatically]?", "Italic citation reference for author name using natbib", "If I have an item, combined with another item, is it still a singular subject in the sentence? For example: This paper, combined with some glue, makes for an afternoon of art projects. This paper, combined with some glue, make for an afternoon of art projects. All of my experience tells me that it should be the first, but I have multiple people arguing for the second.", "I am trying to include a figure into LaTeX from a paper originally created using MS Word. I have already converted all the text/equations into LaTeX but I can't figure out how to get the figures over without re-drawing them using LaTeX code (which I do not want to do). The image is a plain box (like a tabular) one row by 7 columns with numbers inside each cell. Then I inserted arrows of varying length above and below the box (several short ones and one much longer). I am trying to use the package with the \\includegraphics command. I copied the figure (box and arrows) from my original article into a blank Word doc. The figure only takes up the first 4 or 5 lines of the blank document. I then selected/highlighted the image and printed the selection using 'PDFCreator'. This allowed me to save the image as a .eps file. I then copied and pasted the eps file into the folder where all my .tex files are saved. When I compile the document using pdftexify there is a blank space where the image should be. In the console I get the following message when I compile the document: [27] &lt;Fig3-eps-converted-to.pdf, id =105, 391.4625pt x 74.2774pt&gt; &lt;use Fig3-eps-converted-to.pdf&gt; Overfull \\hbox 1.46153pt too wide) in paragraph at lines 511--516 [] My code looks like this: \\documentclass[12pt]{article} \\usepackage{graphicx} \\usepackage{epstopdf} \\begin{document} %Text \\includegraphics{fig3.eps} %text \\end{document} I have read the sections on graphics in 'LaTeX: A Document Preparation System' and 'The Not So Short Introduction to LaTeX2e' but I still can't figure this out. Should I maybe use a PNG image since it is a pretty basic figure? Any advice on how to properly transfer images from a word doc to .eps format and/or how to get those .eps files into LaTeX properly would be a huge help." ]

[ "Why does English spelling use silent letters?", "Proper way to exit iPhone application? I am programming an iPhone app, and I need to force it to exit due to certain user actions. After cleaning up memory the app allocated, what's the appropriate method to call to terminate the application?", "I am not experienced in Number Theory but what I know is that some results of this filed are applicable in other areas, e.g. algebra. For sure FLT made (and makes) people be interested in Number Theory leading to the development of new methods which can be themselves applied not only for the proof of FLT (like financial problems motivated somehow development of stochastic analysis). I am interested - if there are applications or implications of FLT itself? More precisely: if the fact \"for each $n\\geq3$ there are no integer solutions of $a^n+b^n=c^n$\" leads to solutions of problems which are not in the field of Number Theory? I would specify that I wonder about some problems which are already formulated: since FLT is known for more then 300 years I am pretty sure that there were formulated hypothesis which follow from FLT directly (if there are such hypothesis not in the field of Number Theory).", "How do I resize an encrypted LVM to install another copy of Ubuntu? I have an old PowerBook which has been happily running Ubuntu Server for a few months. Now I want to repartition the hard drive and install Ubuntu Client, while keeping my existing installation intact. When I first installed Ubuntu, I chose to erase the entire hard drive and use it as an encrypted LVM. Now, the installer seems to recognize the partitions on the drive, but it never prompts me for the password to the LVM. How do I make room for another installation alongside my current one?", "Populating cascading dropdown lists in JSP/Servlet", "Why is $(2, 1+\\sqrt{-5})$ not principal? Why is $(2, 1+\\sqrt{-5})$ not principal in $\\mathbb{Z}[\\sqrt{-5}]$? Say $(2,1+\\sqrt{-5})=(\\alpha)$, then since $2\\in(2,1+\\sqrt{-5})$ we have $2\\in (\\alpha)$, so $\\alpha\\mid2$ in $\\mathbb Z[\\sqrt{-5}]$. Writing $2=\\alpha\\beta$ in $\\mathbb Z[\\sqrt{-5}]$ and taking norms, $4=N(\\alpha)N(\\beta)$ in $\\mathbb Z$, so $N(\\alpha)\\mid4$ in $\\mathbb Z$. Similarly, since $\\sqrt{-5}\\in(\\alpha)$ we get $N(\\alpha)\\mid5$, thus $N(\\alpha)$ is a common divisor of $4$ and $5$, therefore $N(\\alpha)=(1)$, so $\\alpha$ is a unit. But that means $1\\in (2,1+\\sqrt{-5})=(\\alpha)$, so it must be the whole ring, but it cannot to reach a contradiction, so how can I find an element, which is not in $(2, 1+\\sqrt{-5})$. Or is there a simpler method ? (Maybe not UFD would imply not PID)", "What are some practical examples of a constant current source? Please don't state the obvious that nothing is a perfect constant current source. And please do not give examples of how to create them from components. I looked at this which stated the obvious - that you can not have a perfect current source. So when I say constant current source, I am not referring to the mathematical concept used in circuits, but \"natural\" components that provide a close approximation to this. Key word is approximation. A bit of research pulled up one interesting example which was a solar cell. Is this a valid example? A google search pulls up a similar Quora question . Which gave the example of a solar cell. This is a more technical site and I was looking for a more engineering answer not a mathematical or laymen's answer. Thanks.", "Setting up LVM Snapshot as a backup/restore point in ubuntu", "How to prove that exponential grows faster than polynomial? In other words, how to prove: For all real constants $a$ and $b$ such that $a &gt; 1$, $$\\lim_{n\\to\\infty}\\frac{n^b}{a^n} = 0$$ I know the definition of limit but I feel that it's not enough to prove this theorem.", "When we want to open an application or file from the terminal, we type, say, okular file.dvi This opens the application, but also shows the status of the application. We cannot close the terminal, because it kills the process. Unfortunately, if you're trying to, for example, create a LaTeX file, you will need one tab for the text editor, one for the dvi file, and so on. And if you're trying to open all windows from the terminal, you can forget it. I'm trying use the terminal as much as possible, and while I have Yakuake, it is still a bother having so many tabs and seeing which of those have an application I've killed and so on. So, is there a way to open an application/file from the terminal so that the status doesn't show and immediately gives the prompt so that we can use it to open more applications?", "I got 2 ghast tears after I thought I deflected a fireball back at the ghast (with my looting 3 sword). But I was pretty close, so I might have just hit it. I'm not sure. If I deflect a fireball with a looting sword and it kills the ghast, do I still get the looting bonus?", "How to correctly post a Q&A style question (i.e.self answer) without it failing minimal understanding As I understand it Q&amp;A style questions are but a self answered question should be judged independently of the answer. Often after I've solved a problem I would like to share the question and answer on stack overflow (and have on a couple of occasions) but how to show &quot;minimal understanding of the problem&quot; is always challenging. For example I have been looking into the following question How can I plot a straight line in the JMonkey Engine library I'm trying to plot straight lines between vertices that I specify using the JMonkey Engine 3D graphics library. So for example if I was to try to plot between: (2,0,0) (-1,0,1) (0,1,1) (1,1,1) (1,4,0) Then I would get: This is something I do (and forget how to do) relatively often and the answer is harder to find than you'd imagine ( provides everything needed to figure it out but its spread out over several posts and isn't a complete solution on its own). Therefore I want to provide a Q&amp;A for it but at present this question feels like it would fail the minimal understanding test Questions must demonstrate a minimal understanding of the problem being solved. Tell us what you've tried to do, why it didn't work, and how it should work Should I make up some imaginary problem? (Probably the final source code messed up a bit) Or mention in the question that I’m self answering to assuage some of the normal &quot;This is not a do your work for you site&quot; comments.", "Suppress \"In:\" biblatex", "Let $X,Y,Z$ Banach spaces and $A:X\\rightarrow Y$ and $B:Y\\rightarrow Z$ linear maps with $B$ bounded and injective and $BA$ bounded. Prove that $A$ is bounded as well. If I knew that $B(Y)$ is closed I'd have a bounded linear map $B^{-1}:B(Y)\\rightarrow Y$ by the bounded inverse theorem. Therefore $A=B^{-1}BA$ is bounded. How to prove the claim if $B(Y)$ is not closed.", "I want to collect the most common mistakes, misconceptions, pitfalls, etc that (La)TeX and Friends users make. Please one answer for each mistake, misconception, pitfall, etc. I am only interested in more technical, objective cases rather than psychological, social, subjective cases. From this complete infinite list of technical and objective cases, we can have a reference how to teach newbies much better directly or indirectly via writing a good book. The technical and object cases are, for example, as follows. Beginners sometimes use $\\huge E=mc^2$ with the hope they will get a huge formula. It actually does not produce the expected result. The correct way is \\huge $E=mc^2$. Beginner sometimes use longtable inside table because they assume longtable is the longer version of tabular which is able to be sandwiched in table. etc.", "get current user info using jquery ,REST and csom My goal is to get the login name and picture for the current user. I am using SharePoint 2013 Foundation. I tried three method and non of then worked correctly: This is with jQuery SPServices: function getCurrentUserInfo() { var thisUsersValues = $().SPServices.SPGetCurrentUser({ fieldNames: [\"ID\", \"Name\", \"Picture\"], debug: false }); var name = thisUsersValues[\"Name\"]; var ID = thisUsersValues[\"ID\"]; var SIPAddress = thisUsersValues[\"Picture\"]; } But I am getting this error: SCRIPT438: Object doesn't support property or method 'replace' File: jquery.SPServices-2014.01.js, Line: 2414, Column: 17 REST API method: function getinfo(loginName) { var theData = { \"propertiesForUser\": { \"__metadata\": { \"type\": \"SP.UserProfiles.UserProfilePropertiesForUser\" }, \"accountName\": loginName, \"propertyNames\": [\"PreferredName\", \"PictureURL\"] } }; var requestHeaders = { \"Accept\": \"application/json;odata=verbose\", \"X-RequestDigest\": jQuery(\"#__REQUESTDIGEST\").val() }; jQuery.ajax({ url: _spPageContextInfo.webAbsoluteUrl + \"/_api/SP.UserProfiles.PeopleManager/GetUserProfilePropertiesFor\", type: \"POST\", data: JSON.stringify(theData), contentType: \"application/json;odata=verbose\", headers: requestHeaders, success: function (data) { document.getElementById(\"profilelink\").href = userProfileProperties[1];; document.getElementById(\"username\").innerHTML = userProfileProperties[0]; if (userProfileProperties[1] !== null) { document.getElementById(\"Userprofileimage\").src = userProfileProperties[1]; } }, error: function (jqxr, errorCode, errorThrown) { console.log(jqxr.responseText); } }); } Error: \"{\\\"error\\\":{\\\"code\\\":\\\"-1, Microsoft.SharePoint.Client.InvalidClientQueryException\\\",\\\"message\\\":{\\\"lang\\\":\\\"en-US\\\",\\\"value\\\":\\\"The method GetUserProfilePropertiesFor cannot be invoked as its parameter propertiesForUser is not supported.\\\"},\\\"innererror\\\": {\\\"message\\\":\\\"The method GetUserProfilePropertiesFor cannot be invoked as its parameter propertiesForUser is not supported.\\\" ,\\\"type\\\":\\\"Microsoft.SharePoint.Client.InvalidClientQueryException\\\",\\\"stacktrace\\\":\\\" With CSOM: //SP.SOD.executeOrDelayUntilScriptLoaded(getUserProperties, 'SP.UserProfiles.js'); function getUserProperties(targetUser) { // get the target users domain name and account name. var tUser = targetUser.substring(7); // Get the current client context. var clientContext = new SP.ClientContext.get_current(); //Get PeopleManager Instance var peopleManager = new SP.UserProfiles.PeopleManager(clientContext); // Get the properties to retrieve var profilePropertyNames = [\"PreferredName\", \"PictureURL\"]; var userProfilePropertiesForUser = new SP.UserProfiles.UserProfilePropertiesForUser( clientContext, tUser, profilePropertyNames); // Get user profile properties for the target user userProfileProperties = peopleManager.getUserProfilePropertiesFor(userProfilePropertiesForUser); // Load the UserProfilePropertiesForUser object. clientContext.load(userProfilePropertiesForUser); //Execute the Query clientContext.executeQueryAsync(onRequestSuccess, onRequestFail); } I really don't understand where the issue is. Does anyone have an idea?", "How to find files containing two strings in different lines", "I cannot update my Kali Linux, when trying to execute apt-get update I get this error message: # apt-get update Get:1 http://kali.mirror.garr.it/mirrors/kali kali-rolling InRelease [30.5 kB] Err:1 http://kali.mirror.garr.it/mirrors/kali kali-rolling InRelease The following signatures were invalid: EXPKEYSIG ED444FF07D8D0BF6 Kali Linux Repository &lt;[email protected]&gt; Reading package lists... Done W: GPG error: http://kali.mirror.garr.it/mirrors/kali kali-rolling InRelease: The following signatures were invalid: EXPKEYSIG ED444FF07D8D0BF6 Kali Linux Repository &lt;[email protected]&gt; E: The repository 'http://kali.mirror.garr.it/mirrors/kali kali-rolling InRelease' is not signed. N: Updating from such a repository can't be done securely, and is therefore disabled by default. N: See apt-secure(8) manpage for repository creation and user configuration details. If you need my kernel version: # uname -a 4.13.0-kali1-amd64 #1 SMP Debian 4.13.10-1kali2 (2017-11-08) x86_64 GNU/Linux How can I fix this?", "Powering down the display in XP with a command Is there a command to power down the display in Windows XP? That is, a command that causes the video card to stop sending a signal to the monitor until input is received, much as power management does after a time.", "Prove that $a^2(b+c-a)+b^2(a+c-b)+c^2(a+b-c) \\leq 3abc.$" ]

[ "Evaluating $\\int \\sqrt{1 + t^2} dt$? How do we solve (i.e. get the closed form of) $\\int \\sqrt{1 + t^2} dt$ ? shows the closed form of it but not the steps in solving it. I think I need some algebraic trick.. I thought of some hyperbolic functions and their derivatives and equalities: If I make $ t = \\sinh x$, then I can reduce the integral to $$ \\int \\cosh ^2 x dx $$ though I'm not sure if this is valid. But from here, I cannot go on evaluating the integral...", "A question about $f(x)\\equiv 0$", "Radiation– white vs black house, hot or cool? In my book's thermodynamics chapter, it says that an \"object that radiates heat faster also absorbs heat faster. This means that an object that is a more efficient radiator comes to equilibrium with its environment more quickly. With this in mind, is it better to paint your house black or white?\" I am confused which it would be. The book says white because \"in summer, you house is cooler than the environment and white reflects away the heat. In winter your house is warmer than the environment and white radiates away the heat\"", "How do you get the root namespace of an assembly? Given an instance of System.Reflection.Assembly.", "Best way to clone an installation (copying to identical hardware) Kind-of like but slightly different (I think), in that I have 6 identical Acer Aspire Revo R3610 machines. One is (almost) configured to my requirements - when I'm done preparing it I'd like to make the other 5 machines absolutely the same. I'm very new to Ubuntu, what's the most straightforward (easiest) way of doing this? The machines are going to live on different networks if that might otherwise be a problem (eg with Windows you can clone disks but you then have to make registry changes afterwards if they're going to run on the same network etc). The hardware in all 6 machines is, I stress, the same! How can I efficiently clone one source image on to these identical machines? Please restrict one software/solution per answer", "Why is this sequence of functions not uniformly convergent? For the following sequence of functions and its limit function, we can see that $f_n(x)$ is clearly pointwise convergent $$f_n(x) = x^n\\text{ }\\forall x\\in[0,1]\\text{ and }\\forall n\\in\\mathbb N^*\\\\ f(x) = \\begin{cases}0&amp;\\text{if } x\\in[0,1)\\\\1&amp;\\text{if } x=1\\end{cases}$$ However, I was wondering why this is not uniformly convergent. The condition for uniform convergence is: $$|f_n(x) - f(x)| &lt; \\epsilon,\\ \\ \\ \\forall x \\text{ when } n &gt; N$$ Now most sources present an argument along the lines of: assume that $f_n(x)$ is uniformly convergent and that $0 &lt; x &lt; 1$, this means that $x^n&lt;\\epsilon$ whenever $n&gt;N$. Specifically, this would mean $x^{N+1}&lt;\\epsilon$ for some fixed $N$. But if we now pick $x$ such that $1 &gt; x &gt; ε^{\\frac{1}{N+1}}$, then this would lead to a contradiction, therefore $f_n(x)$ is not uniformly convergent. However, I was wondering why couldn't we take $n$ to infinity. If $0 &lt; x &lt; 1$, then $\\lim_{n\\rightarrow \\infty} |f_n(x) - f(x)| = 0$ (which is less than $\\epsilon$). Now since $|f_n(x) - f(x)|$ will always be $0$ if $n &gt; \\infty$, then wouldn't this be uniformly convergent?", "Here at the Genealogy and Family History Stack Exchange we see many questions about relationship mapping which is also known as: relationship calculation kinship terminology etc If you are just trying to understand how to calculate \"cousins and removes\" then provides an excellent guide. However, if you are seeking an English term for a more complicated relationship between two members of an extended family, rather than asking a question like: site users are encouraged to first review the answers below. Note: This Q&amp;A arises from and is set to to help make it canonical.", "How can I get ssh-agent working over ssh and in tmux (on OS X)? I have a private key set up for my github account, the passphrase to which is, I believe, stored in OS X's keychain. I certainly don't have to type it in when I open a terminal window and enter ssh [email protected]. However, when I'm running bash over an ssh session, or locally inside a tmux session, I have to type in the passphrase every single time I attempt to ssh to github. suggests that a similar problem exists with screen, but I don't really understand the issue well enough to fix it in tmux. There's also which includes a fairly complicated solution, but for zsh. EDIT: In response to , from a local terminal I get the following output: [~] $ echo $SSH_AUTH_SOCK /tmp/launch-S4HBD6/Listeners [~] $ ssh-add -l 2048 [my key fingerprint] /Users/richie/.ssh/id_rsa (RSA) [~] $ typeset -p SSH_AUTH_SOCK declare -x SSH_AUTH_SOCK=\"/tmp/launch-S4HBD6/Listeners\" Whereas over ssh or in tmux I get: [~] $ echo $SSH_AUTH_SOCK [~] $ ssh-add -l Could not open a connection to your authentication agent. [~] $ typeset -p SSH_AUTH_SOCK bash: typeset: SSH_AUTH_SOCK: not found echo $SSH_AGENT_PID returns nothing whatever shell I run it from.", "Can a Dungeons and Dragons 4e character take D&D Essentials feats? In Heroes of the Fallen Lands many of the core feats have been streamlined, some paragon feats have become available to all levels. Before that feats were tiered by level: heroic, paragon, epic. Can a character that was made before the Heroes of the Fallen Lands publication use Heroes of the Fallen Lands feats?", "Every time I try update (using sudo apt-get update) my Ubuntu I get this problem: W: The repository 'cdrom://Ubuntu 16.04 LTS _Xenial Xerus_ - Release amd64 (20160420.1) xenial Release' does not have a Release file. N: Data from such a repository can't be authenticated and is therefore potentially dangerous to use. N: See apt-secure(8) manpage for repository creation and user configuration details. W: The repository 'ppa.launchpad.net/kirillshkrogalev/ffmpeg-next/ubuntu xenial Release' does not have a Release file. N: Data from such a repository can't be authenticated and is therefore potentially dangerous to use. N: See apt-secure(8) manpage for repository creation and user configuration details. E: Failed to fetch cdrom://Ubuntu 16.04 LTS _Xenial Xerus_ - Release amd64 (20160420.1)/dists/xenial/main/binary-amd64/Packages Please use apt-cdrom to make this CD-ROM recognized by APT. apt-get update cannot be used to add new CD-ROMs E: Failed to fetch cdrom://Ubuntu 16.04 LTS _Xenial Xerus_ - Release amd64 (20160420.1)/dists/xenial/main/binary-i386/Packages Please use apt-cdrom to make this CD-ROM recognized by APT. apt-get update cannot be used to add new CD-ROMs E: Failed to fetch ppa.launchpad.net/kirillshkrogalev/ffmpeg-next/ubuntu/dists/xenial/main/binary-amd64/Packages 404 Not Found E: Failed to fetch ppa.launchpad.net/kirillshkrogalev/ffmpeg-next/ubuntu/dists/xenial/main/binary-i386/Packages 404 Not Found E: Some index files failed to download. They have been ignored, or old ones used instead. How can I fix it? I use Ubuntu 16.04 LTS", "Generating data with a given sample covariance matrix", "How to redirect standard output to multiple log files? The following does not work: some_command 1&gt; output_log_1 output_log_2 2&gt;&amp;1", "With a Canon 550D camera and a Tamron 18-270 mm zoom lens, I tried to fix shutter time, aperture (f/8.0 to cover all zoom range), and ISO, so the exposure meter read 0.0 with 18 mm focal length and while focusing on a uniform white wall. Then I changed to 270 mm focal length, but the exposure reading did not change significantly (only to -0.7). However, I had expected exposure to change, since only (18 mm / 270 mm) ** 2 = 1/225 of the wall is now covered in compare the coverage when focal length is 18 mm, thus only 1/225 of the light gets to the sensor after the change of focal length. Why does exposure not change when narrowing the field of view with change of focal length?", "If $|G/H|=4$ then $G$ is union of three proper subgroups Let $G$ be a finite group and $N$ a normal subgroup of $G$ of index $4$. Prove that $G$ has a subgroup of index $2$ (hence normal) and if $G/H$ is not cyclic then $G$ is equal to the union of three proper subgroups. I understand that $G/H$ is isomorphic to $\\mathbb{Z}_4$ or $\\mathbb{Z}_2\\times \\mathbb{Z}_2$. Let $K^*$ be a subgroup of $G/H$ of order $2$. Then $K^*\\cong K/H$ for some $K$ such that $H$ is normal in $K$ and hence $[G:K]=[G/H:K/H]=4/2=2$. If $G/H$ is not cyclic then $G/H\\cong \\mathbb{Z}_2\\times \\mathbb{Z}_2$. I don't know how to prove $G$ is the union of three subgroups. Could it be true that as $G/H$ is the union of three proper subgroups $K_1^*,K_2^*,K_3^*$ then the corresponding groups $K_1,K_2,K_3$ have union equal to $G$? Would anyone give me a hint to prove this? Thank you.", "launch sms application with an intent", "What are the rules of parallelism? I've been reading a lot about it since yesterday and all I encounter is \"They must have the same grammatical form\"? What does this exactly mean? I know how to make parallel sentences with gerunds. The things get trickier when it comes to using modifiers. For example: I love using the phone that you bought me and the computer. On the left side of the conjunction there is a noun phrase that consists of an article + noun + another modifier and on the right side there is an article + noun. They are both noun phrases but the first one has additional modifier. Is that still considered a parallel sentence? Another example: I like to swim and to feel good. Here on the right side of the conjunction there is an infinitive and on the left side there is an infinitive + complement? Is that parallel?", "I have four competing models which I use to predict a binary outcome variable (say, employment status after graduating, 1 = employed, 0 = not-employed) for n subjects. A natural metric of model performance is hit rate which is the percentage of correct predictions for each one of the models. It seems to me that I cannot use ANOVA in this setting as the data violates the assumptions underlying ANOVA. Is there an equivalent procedure I could use instead of ANOVA in the above setting to test for the hypothesis that all four models are equally effective?", "Does a finite $[E:K]_s$ imply that $[E_s:K]$ is finite? Let $E/K$ be an algebraic extension of fields and denote by $E_s$ the separable closure of $K$ in $E$, i.e. the set of all elements of $E$ that are separable over $K$ (which can be shown is a (separable) subfield of $E$). I would like to show that the implication $\\left[E:K\\right]_s &lt; \\infty \\implies \\left[E_s:K\\right] &lt; \\infty$ holds, where $\\left[E:K\\right]_s$ denotes the separable degree of $E/K$ and $\\left[E_s:K\\right]$ the 'ordinary' degree of $E_s/K$. In the textbook I am learning with, it is said that one could use the Primitive Element Theorem to do this, but I would also be fine with any other approach, as long as it's not getting too fancy and staying in the realm of 'common' textbook theorems known when dealing with separable extensions (and I didn't see how the Primitive Element Theorem would help). This is not my focus (I want to write a Bachelor's thesis about polynomial factorizing elements of $\\mathbb{Z}[X]$), but I'm in the process of reading into commutative algebra after about 1.5 years break from it. My idea was something like assuming $\\left[E_s:K\\right] &lt; \\infty$ and $\\left[E_s:K\\right] = \\infty$ to construct infinitely many $K$-homomorphisms $E_s/K \\longrightarrow C/K$, where $C$ is some algebraic closure of $E_s$, which would then contradict $\\left[E_s:K\\right]_s = \\left[E_s:K\\right] &lt; \\infty$. Of course, an infinite basis would yield infinitely many $K$-vector space homomorphisms, but getting (infinitely many) ring morphisms seems to by an entirely different ting (unsurprisingly so...). Thought of using something like Given two roots of the minimal polynomial of one of the infinitely many elements of a $K$-basis of $E_s/K$, there is a $K$-morphism $E_s/K \\longrightarrow C/K$ that sends one to the other. but this didn't seem very fruitful. I admit I haven't spent hours on this, I just didn't get very far and should focus on moving on, while still getting an answer on the 'howto' along the road would be really nice.", "explicit formula for recurrence relation $a_{n+1}=2a_n+\\frac{1}{a_n}$ For $n\\in\\mathbb N$, $$a_{n+1}=2a_n+\\frac{1}{a_n},\\quad a_1=1. $$ Can any one give an explicit formula for all $a_n$? If such an explicit general formula doesn't exist, please explain it. I've tried to figure out the $n$-iterated function $f^{(n)}$ where $f(x)=2x+1/x$ or even $f(\\tan(t))$. But in either cases, I failed.Since the recurrence isn't linear nor homogeneous,the generating function method doesn't apply here.", "Water Wars: Time Travel TV Show?" ]

[ "Why doesn't the tilde (~) expand inside double quotes?", "Is there a way to force Google Chrome to remember passwords for sites that have autocomplete turned off? Clarification: I am a programmer, but ideally, I'd like a method that I could help regular users implement, too.", "How secure would github hosting be for private repositories?", "How to replace text between quotation marks with something from another file? I have the following kind of text: $OU = 'or'; $DINHEIRO_CAIXA = 'Cash balance'; $PAGINA = 'Page'; $DE = 'from'; $ENVIAR = 'Send'; $PRINCIPAL = 'Main'; I've already got all the text within the single quotation marks using cat arquivo | grep -oP &quot;'[^']+'&quot; | tr -d &quot;'&quot; This extracted text was then translated to Portuguese, but now I don't know how to replace the original text between single quotation marks with the translated text, I was looking for something like $OU = 'ou'; $DINHEIRO_CAIXA = 'Dinheiro em caixa'; $PAGINA = 'Pagina'; $DE = 'de'; $ENVIAR = 'enviar'; $PRINCIPAL = 'Principal'; I've tried using grep -F to replace the file itself, but it failed miserably because the pattern didn't match since I don't have the quotation marks on the new file, is there a way to do this?", "How to include time factor in a mixed model (investigating the interaction between two factors and time)?", "\"wait on\" or \"wait for\"? Officials are waiting on autopsy results for Oscar-winning actor Philip Seymour Hoffman. New York police suspect a drug overdose, possibly heroin. I am curious about the preposition on in the sentence, because I usually say \"wait for\" instead of \"wait on\". Does it still have the same meaning if I change on to for? Just as follows: Officials are waiting for autopsy results for Oscar-winning actor Philip Seymour Hoffman. New York police suspect a drug overdose, possibly heroin.", "Proof of the equality $\\sum\\limits_{k=1}^{\\infty} \\frac{k^2}{2^k} = 6$", "Black screen after suspend-after moving to the nvidia official drivers (not priority)", "I have a bash script which must call another bash script which varies per-user in order to get some configuration information, like so: somescript: #!/bin/bash ${HOME}/.ssconfig echo \"Hello, ${VARIABLE}!\" ~/.ssconfig #!/bin/bash VARIABLE=world Which, instead of giving me Hello, world! as expected, gives me Hello, ! How can I pass variables up from a script to the one that called it?", "What is the proper way to extend the Fibonacci numbers to negative numbers? I have a feeling this question is a duplicate, but it's not coming up in \"Questions that may already have your answer.\" We all know very well that $F(0) = 0$, $F(1) = 1$ and $F(n) = F(n - 2) + F(n - 1)$ for all $n &gt; 1$. I'm wondering about $n &lt; 0$. My first thought was $F(-n) = -F(n)$, which is appealing from a multiplicative point of view, as it seems to preserve certain identities, like $F(n)^2 = F(n - 1) F(n + 1) - (-1)^n$. But it doesn't quite make sense from an additive point of view, it doesn't seem to work both \"forwards\" and \"backwards.\" For example, it would give us $F(-1) + F(0) = -1 \\neq F(1)$. How do we extend $F(n)$ to negative $n$ so as to maintain both the related identities and the basic defining identity?", "I was trying to experiment with docker, Ubuntu 14.04, 64-bit. I managed to run an image, and I gave it the path on one of my removable drives, /media/Drive1. Now, whenever I reboot, I see there is a /media/Drive1 with only a docker directory inside it, and the actual drive which should be Drive1 ends up mounted on /media/Drive11, and this happens every reboot - even when I unmount these drives, and do a sudo rm -rfv /media/Drive1 before rebooting! So something probably creates /media/Drive1 before it is fully mounted, and I guess that something is docker, because when I boot, I have: $ ps axf | grep docker 2085 ? Ssl 0:00 /usr/bin/docker -d So, how can I disable the docker autostart, so it doesn't interfere with the mounting of external USB drives at boot?", "How map multiple inputText to an array property?", "What is a smart pointer and when should I use one?", "Let's say we have this code for a LWC: &lt;!-- helloExpressions.html --&gt; &lt;template&gt; &lt;div class=\"slds-m-around_medium\"&gt; &lt;lightning-input name='firstName' label=\"First Name\" onchange={handleChange}&gt;&lt;/lightning-input&gt; &lt;lightning-input name='lastName' label=\"Last Name\" onchange={handleChange}&gt;&lt;/lightning-input&gt; &lt;p class=\"slds-m-top_medium\"&gt;Uppercased Full Name: {uppercasedFullName}&lt;/p&gt; &lt;/div&gt; &lt;/template&gt; and this is the JS file: // helloExpressions.js import { LightningElement, track } from 'lwc'; export default class HelloExpressions extends LightningElement { @track firstName = ''; @track lastName = ''; handleChange(event) { const field = event.target.name; if (field === 'firstName') { this.firstName = event.target.value; } else if (field === 'lastName') { this.lastName = event.target.value; } } get uppercasedFullName() { return `${this.firstName} ${this.lastName}`.toUpperCase(); } } firstName and lastName have been decorated with @track. Now as per the documentation, decorating a property with @track makes it private and reactive, while to mark a property public and reactive, use @api. So if I just change the decorator to @api for both these variables, it should work. I am referring these from the same component only. But it's not working. UPDATE: 27th Feb -------------------- Somehow it's working today. I just changed the decorator of the variables to api. import { LightningElement, api } from 'lwc'; export default class HelloExpressions extends LightningElement { @api firstName = ''; @api lastName = ''; handleChange(event) { const field = event.target.name; if (field === 'firstName') { this.firstName = event.target.value; } else if (field === 'lastName') { this.lastName = event.target.value; } } get uppercasedFullName() { return `${this.firstName} ${this.lastName}`.toUpperCase(); } } So it's working.", "pgfplots: lines and markers in different colors With pgfplots, I am creating a simple coordinate plot with error bars like this: \\documentclass[crop,10pt]{standalone} \\usepackage[english]{babel} \\usepackage{pgfplots} \\begin{document}% \\setlength{\\linewidth}{246pt}% \\begin{tikzpicture} \\begin{axis}[ width=\\linewidth, ytick pos = left, xtick pos = left, clip=false, axis on top, tick align = outside, yticklabel style={% /pgf/number format/fixed, /pgf/number format/precision=1, /pgf/number format/fixed zerofill }, ytick scale label code/.code={}, xlabel={X}, ylabel={Y}, ] \\addplot[mark=*] plot[ error bars/.cd, y dir=both, y fixed=0.0001 ] coordinates{(1,0.0005) (1.1,0.0013) (5,0.0015)}; \\end{axis} \\end{tikzpicture} \\end{document} In the original plot I have a lot more points. I would now like the line and the markers (including the error bars) to have different colors to better distinguish the line from the error bars. Is that somehow possible? The only way I found so far is to plot the data just as a line in one color and then plot it again just as markers in another color. This works, but I guess there must be some better solution to this. Thanks for the support, John", "How can I completely remove a objects (e.g. particle system or groups used in particle systems) in blender using python? The problem is this: I have a script, with which I create a scene (e.g. adding some normal objects and some group of objects with a particle system). For a research study I would like to repeat that that several times, without restarting blender. So I can create a scene, delete everything, e.g. with a script like this: import bpy scn = bpy.context.scene for obj in scn.objects: obj.select = True bpy.ops.object.delete() If I rerun the script to recreate the scene with objects using particle system, the latter is not shown in the scene anymore (only the placeholders of the particle system). Now I'm not sure where exactly the problem lies, but I guess not everything is immediately deleted, running the script above. Only the startup of blender helps (but that's not what I want) or pushing the purge button. The purge button seems to start the command: bpy.ops.outliner.orphans_purge() But I can't get this piece of code to run in the console. It says that \"the context is incorrect\". Is there a way to purge the unused data by python script? Thanks a lot for any help.", "Is there a problem with defrosting meat on the counter? I generally defrost meat on the kitchen counter. A friend of mine suggested that this was dangerous and suggested that I defrost meat in the refrigerator. I am no biologist but it seems to me that as long as the meat doesn't get warm defrosting it on the counter should be safe. Generally, I remove the frozen items from the freezer and place them on a plate on the counter in the packaging they were frozen in. When they are mostly / completely thawed I place the meat in the refrigerator. Am I wrong and should I be defrosting in the refrigerator?", "A linking verb is a verb which connects a subject to its predicate without expressing an action. A linking verb is used to re-identify or describe its subject. Ex: Alan is a beast. Alan seems drunk. But I would say that some linking verbs can be used with \"continuous tenses\" &amp; other linking verbs can not, but I am not sure. (linking verb) to experience a particular feeling or emotion Ex: I’m feeling a little better today. Do you still feel hungry? So, feel in this meaning can be used with continuous tenses But I would think this sentence \"Do you still feel hungry?\" does not make much sense because it uses \"simple present tense\" which expresses something that happens regularly. Noone would feel hungry regularly. So, that sentence \"you feel hungry\" would mean \"you always feel hungry\". (linking verb) (not used in the progressive tenses): to have a particular physical quality which you become aware of by touching adj. The water feels warm. Its skin feels really smooth. says \"Speakers sometimes use the Simple Present to express the idea that an action is happening or is not happening now. This can only be done with Non-Continuous Verbs and certain Mixed Verbs.\" so, \"The water feels warm.\" could mean \"The water is always warm\" (simple present expressing things that happen regularly - more or less permanent action) But \"The water feels warm.\" could mean \"The water is warm now\" (simple present with non-continuous verb expressing things that is happening now - a temporary action) : (linking verb) to seem; to appear adj. to look pale/happy/tired That book looks interesting. In dictionary, (linking verb) (not used in the progressive tenses): to give the impression of being or doing something adj. She didn't appear surprised at all. (to somebody) (to be) something (not used in the progressive tenses): to give the impression of being or doing something (synonym: appear) adj. You seem happy. So, we cannot say \"you are seeming happy\" or \"you are appearing happy\". But I am not sure I can say \"You are looking good\" (sounds right to my ears) or \"That book is looking interesting.\" (doesn't sound right to my ears) But we can say \"The future’s looking good.\" () So, some verbs has the same meaning but one can be used with \"continuous\" &amp; the other can not, right? Ex: \"you are looking happy\", but \"you seem happy\".", "How do I force Python's print function to output to the screen?", "Subfields of finite fields" ]

[ "Fields - Proof that every multiple of zero equals zero This is one of my first proofs about fields. Please feed back and criticise in every way (including style and details). Let $(F, +, \\cdot)$ be a field. Non-trivially, $\\textit{associativity}$ implies that any parentheses are meaningless. Therefore, we will not use parentheses. Therefore, we will not use $\\textit{associativity}$ explicitly. By $\\textit{identity element}$, $F \\ne \\emptyset$. Now, let $a \\in F$. It remains to prove that $0a = 0$. \\begin{equation*} \\begin{split} 0a &amp;= 0a + 0 &amp;&amp; \\quad \\text{by }\\textit{identity element }(+ ) \\\\ &amp;= 0a + a + -a &amp;&amp; \\quad \\text{by }\\textit{inverse element }(+ ) \\\\ &amp;= 0a + 1a + -a &amp;&amp; \\quad \\text{by }\\textit{identity element }(\\cdot) \\\\ &amp;= (0 + 1)a + -a &amp;&amp; \\quad \\text{by }\\textit{distributivity } \\\\ &amp;= (1 + 0)a + -a &amp;&amp; \\quad \\text{by }\\textit{commutativity }(+ ) \\\\ &amp;= 1 a + -a &amp;&amp; \\quad \\text{by }\\textit{identity element }(+ ) \\\\ &amp;= a + -a &amp;&amp; \\quad \\text{by }\\textit{identity element }(\\cdot) \\\\ &amp;= 0 &amp;&amp; \\quad \\text{by }\\textit{inverse element }(+ ) \\end{split} \\end{equation*} QED PS: Is \"Let $(F, +, \\cdot)$ be a field.\" ok? Besides, I would not want to call $F$ a field, because $F$ is just a set. Also, what do you think about using adverbs like \"Now\"? How would you have said the associativity-thing?", "I'd like to know your opinion on citations in abstracts. At my university, there is no rule on that matter so it's basically a question of preference. Do you think it's okay to have citations in an abstract or do you personally prefer to have the abstract be a ``stand-alone'' piece of work?", "How to Set Firefox 4 to only store History for a set period of time, i.e. one day? I want to setup Firefox 4 to only store my history for 1 day (or some other set period of time), but I can't seem to find an option to do that in the options dialog, all I can see is \"Remember History\", \"Never Remember History\" and \"Custom History Settings\". \"Custom History Settings\" only lets me select what to keep, not for how long. Is there anyway I can do this?", "What graduation gown should a PhD-holder wear when later receiving a Master's in another field?", "Looking for the name of a card-battle cartoon show Looking for a show about a group of three kids/teens who, using cards to change into monsters, fight and recover relics. I believe there are two or three other groups of three also trying to get the relics. In the main group there are two boys and a girl. The boys were both white, one is from a farm and I don't know where the other is from. The girl was dark skinned and either black or blue hair. The three travelled around the world using a red plane. I think they only use one monster primarily. The girl uses a monster created from gas and at one point is green. One of the boys uses a metal robot most of the time and at one point is given another better version of that card to use. I believe the episode for this was called something like green with envy. All I'm getting from the internet is that it may be Chaotic, but that isn't the right show. I also believe the girl's name was Mai and one of the boys were Ky, but I may be wrong.", "Using Apple Script to Manage Sound Output Selection I am brand new here and I have an additional clarification or need additional help for an issue from this thread - In my preference pane, in addition to Headphones and Digital out, I also have 2 apple monitors and would like the option of selecting one of them as out put (namely the first one in the list). Basically I need help with adjust his solution to be able to select the third row or first monitor as sound output. Or a way to accomplish this without knowing how to edit AppleScript for a different setup.", "Subquery in SQL Server Compact Edition", "When does function composition commute? I've read that function composition \"generally does not commute.\" Not counting compositions involving the identity function, and compositions of a function and its inverse, are there examples of functions on the reals (for example) $f, g$ where $fg = gf$ outside of these cases?", "I'll be generous and say it might be reasonable to assume that nature would tend to minimize, or maybe even maximize, the integral over time of $T-V$. Okay, fine. You write down the action functional, require that it be a minimum (or maximum), and arrive at the Euler-Lagrange equations. Great. But now you want these Euler-Lagrange equations to not just be derivable from the Principle of Least Action, but you want it to be equivalent to the Principle of Least Action. After thinking about it for awhile, you realize that this implies that the Principle of Least Action isn't really the Principle of Least Action at all: it's the \"Principle of Stationary Action\". Maybe this is just me, but as generous as I may be, I will not grant you that it is \"natural\" to assume that nature tends to choose the path that is stationary point of the action functional. Not to mention, it isn't even obvious that there is such a path, or if there is one, that it is unique. But the problems don't stop there. Even if you grant the \"Principle of Stationary Action\" as fundamentally and universally true, you realize that not all the equations of motions that you would like to have are derivable from this if you restrict yourself to a Lagrangian of the form $T-V$. As far as I can tell, from here it's a matter of playing around until you get a Lagrangian that produces the equations of motion you want. From my (perhaps naive point of view), there is nothing at all particularly natural (although I will admit, it is quite useful) about the formulation of classical mechanics this way. Of course, this wouldn't be such a big deal if these classical ideas stayed with the classical physics, but these ideas are absolutely fundamental to how we think about things as modern as quantum field theory. Could someone please convince me that there is something natural about the choice of the Lagrangian formulation of classical mechanics (I don't mean in comparison with the Hamiltonian formulation; I mean period), and in fact, that it is so natural that we would not even dare abandon these ideas?", "In the Final Battle, when you remove doom tokens for rolling successes against an Ancient One do you stop counting successes for that roll? In Arkham Horror you have to roll a cumulative number of successes equal to the number of players to knock off a doom token from the Elder God's health. If you reach the number of players worth of successes do you then stop counting for the player and move on or do you count the extra successes against the next doom token? We played it so that you kept on adding them but it meant that we turned Nyalothotep into mince meat quite quickly (One Character was blessed had a fight of 6 a shotgun and Fight +1 skill card though)", "How can I verify the following statement? The image of a morphism $f : A \\longrightarrow B$ is defined as $\\text{Im}(f) = \\text{Ke}r(\\text{coke}r f)$ whenever it exists (e.g., in every abelian category). The morphism $f : A \\longrightarrow B$ factors uniquely through $\\text{Im} f \\longrightarrow B$ whenever $\\text{Im} f$ exists, and $A \\longrightarrow \\text{Im} f$ is an epimorphism and a cokernel of ker $f \\longrightarrow A$ in every abelian category.", "the structure \"like for somebody to do something\"", "Prove that $\\omega + \\omega_1 = \\omega \\cdot \\omega_1 = \\omega^{\\omega_1} = \\omega_1$ I am assuming already that a) the union of countably many countable sets is countable and b) $\\omega_1$ is the least uncountable ordinal, so $x &lt; \\omega_1$ if and only if $x$ is a countable ordinal. I'm not sure if it is relevant but this question also allows The Axiom of Choice. Thanks", "I had created the xml document with xml version=\"1.0\". In that document I need to use the greater than symbol &gt; and less than symbol &lt;. How should I include those symbols? It's not working. &amp;gt; and &amp;lt; are not working for me. Is there any special encoder for this?", "MySQL cartesian product between two SELECT statements", "How Do I Allow A Standard User to Install Programs?", "How do I install an individual package on a Linux system? I need to install a new TeX/LaTeX/ConTeXt package on my computer. I'm running Ubuntu/Fedora/Slackware/Some-Version-Of Linux. What are the possible ways to do this? Note:&nbsp;&nbsp; We get a number of questions that essentially reduce to this one; it was felt a good idea to have one question-and-answer that can cover all the standard methods. See for the discussion. The question-and-answer are CW so that more information can be easily added. If you have information to add, please do so. If you are unsure, leave a comment here or (preferably) in . Comments on the question and answer will be periodically removed to ensure that the information is clear.", "Allow converting comments to answers Allow converting comments to answers, so they can become accepted answers. I asked a question. Someone commented on it, and it was an awesome comment that fully answered the question. As the original questioner, I would like to convert that comment to an answer in order to accept it. Or, if you prefer, I would be okay with being able to simply mark the comment as accepted.", "How do I find packages to install via apt-get", "What is the meaning of this senctence:Excellent answer. Delusions of grandeur. Folks have been institutionalised for less Can an atheist at least agree that existence is a mystery that is bigger than all of us? You’ve got it backwards. It’s religious people who try to fill the mysteries of the universe with beliefs based on nothing emprical. Where atheists say “I don’t know” religious people say “It’s God.” Atheists are comfortable with not knowing everything. They know humans are infinitesimal specks in the universe. Religious people think the entire universe was created for and about them. Talk about grandiosity. Comment:Delusions of grandeur. Folks have been institutionalised for less lol" ]

[ "Possible Duplicate: As answered in I want to use git diff --color=always filename | less -r to get a colored output of my git diffs. Since I use this a lot it would be nice to set up an alias for this. But how to include the filename in this command? I tried the following without success: alias gdiff='git diff --color=always $1 | less -r' Typing gdiff example.php displays the content of example.php with less but ignores the diff part. Any ideas?", "What's the application extension? (aka .exe, .app, etc.) I'm new to Ubuntu. What's the application extension for development reasons? I know Windows is mainly .exe and Mac is .dmg or .app. Does Linux have an unique one?", "Are there any tools for merging CSS? I have a couple CSS files with overlapping CSS selectors that I'd like to programmatically merge (as in not just appending one file to the end of the other). Is there any tool to do this online? or a Firefox extension perhaps?", "say by has the meaning of 6. indicating the period in which something happens: ‘this animal always hunts by night’ Then do we need to say, ‘Why does the sky glitter by night?’ And can’t we say, ‘Why does the sky glitter at night?’? If we can use both, what’s the difference between the two?", "states that the relationship between current ( I ) voltage ( V ) and resistance ( R ) is $$I = \\frac{V}{R}$$ However cause the resistance of a material to go to zero, and as I understand it, as $R \\to 0$, $I \\to \\infty$. Does this present a problem for Ohm's law?", "Keyboard key stuck or not being recognized; how to fix", "subcaption vs. subfig: Best package for referencing a subfigure", "Lorentz Invariant Integration Measure", "Suppose I am given a $2$x$2$ matrix $A=$ \\begin{pmatrix} a &amp; b \\\\ c &amp; d \\end{pmatrix} And an initial vector $x_n$ = \\begin{pmatrix} x_0 \\\\ y_0\\end{pmatrix}. Under repeated iteration $x_{n+1} = Ax_n$, we find that $x_{n+1}$ converges to a line in the direction of the $eigenvector$ of $A$ of the form $X$= $[u,mu]$ where $m$ is the slope of the line. I know that this process somehow also involves the largest $eigenvalue, \\lambda,$ of $A$, though I am unsure how it connects. My question is: How does the largest eigenvalue connect to this repeated iteration, how do I find the slope of the line of convergence $m$, and what is meant by the \"direction of the eigenvector\"?", "Can Wubi use the ISO I already have? The Windows Installer for Ubuntu desktop instructions say that an ISO image for Ubuntu is downloaded during the installation process. But what if I already have an ISO image for Ubuntu. Can I make the Windows Installer use that, so it doesn't have to download an ISO image again? 12.04 LTS and 12.10 are the versions of Ubuntu I'm interested in installing, in case that matters.", "Usage of that: There are many reasons [that] I am confident [that] I will excel at this job I always find it hard to see when it's best to use &quot;that&quot;. Which of these sounds best? There are many reasons I am confident I will excel at this job. There are many reasons that I am confident I will excel at this job. There are many reasons I am confident that I will excel at this job. There are many reasons that I am confident that I will excel at this job. Are there ways of looking at this that I can apply elsewhere? Is there a completely different formulation that works better?", "Is it possible to log back into a Pokemon Go account?", "How do I get powdered mammoth tusk? Am I missing something? I can find plenty of tusks, but I just don't know if I can make them into powder myself or do I have to find them for sale?", "I'm currently working on some logging code that supposed to - among other things - print information about the calling function. This should be relatively easy, standard C++ has a type_info class. This contains the name of the typeid'd class/function/etc. but it's mangled. It's not very useful. I.e. typeid(std::vector&lt;int&gt;).name() returns St6vectorIiSaIiEE. Is there a way to produce something useful from this? Like std::vector&lt;int&gt; for the above example. If it only works for non-template classes, that's fine too. The solution should work for gcc, but it would be better if I could port it. It's for logging so it's not so important that it can't be turned off, but it should be helpful for debugging.", "What is proper way to update D8 DEV?", "How can I display additional boot and shutdown information on the Windows 7 welcome screen? There is a small tweak, I believe it is a registry key, that allows to display additional information on the Welcome and Shutting down screens of Windows 7 (and most likely Vista, too). I have activated this tweak on one of my systems; unfortunately I forgot how I did it, and I can't seem to find the website that originally gave me that information. Usually, the Windows 7 welcome screen will just display \"Welcome\" when logging in. With the tweak activated, my Welcome screen gives status information such as \"Loading user settings\" or \"Preparing desktop\". When shutting down, the default screen simply says \"Shutting down\". With the tweak activated, it gives additional status information such as \"Stopping Windows services\". This appears the same way that Windows gives information when updates are installed or configured during the startup or shutdown procedure, and I find them quite helpful in getting a feel for what task takes how long during that process. The only setting I was able to find is the Boot log checkbox on the Boot tab of the msconfig application. However, this results in Windows displaying console logs of drivers it is loading, etc., instead of the animated Windows title. This is NOT the setting I am looking for. The \"additional boot information\" setting that I have activated on this system still displays the regular animated Windows logo, and only replaces the strings displayed on the blue Welcome and Shutdown screens. Could someone direct me to the registry key (or whatever setting) that is used to get this behaviour? Edit: Here are a few pictures of the enhanced Welcome and Shutdown screens taken with my mobile phone—they're in German though. Login screen \"Waiting for User Profile Service\" Login screen \"Preparing desktop\" Logout screen \"Stopping Windows services\":", "Is there any online resource that can tell me what visa rules are for passport holders of a specific country? When thinking about travelling, I often have to think about a place to visit, and then look up visa rules for that particular country. This can be a fairly painful process because official government sites can often be hard to find, and advice on (say) guidebooks or Wikitravel tends to be generic. Is there any resource where I can enter my nationality/residency, and then look up a list of visa rules for various countries?", "Use $\\delta-\\epsilon$ to show that $\\lim_{n\\to\\infty} a^{\\frac{1}{n}} = 1$? Hope this is a meaningful question, but I'm curious if is possible to show that $$\\lim_{n\\to\\infty} a^{\\frac{1}{n}}=1, \\text{where }a&gt;0$$ using $\\delta-\\epsilon$ directly or other methods. One method that I am aware of is to use the following: If $\\{s_n\\}$ is a nonzero sequence, then $\\liminf\\bigl|\\frac{s_{n+1}}{s_n}\\bigr|\\le \\liminf |s_n|^{\\frac{1}{n}}\\le \\limsup |s_n|^{\\frac{1}{n}}\\le\\limsup\\bigl|\\frac{s_{n+1}}{s_n}\\bigr|$", "Use of 'const' for function parameters", "Why don't electrons crash into the nuclei they \"orbit\"? I'm having trouble understanding the simple \"planetary\" model of the atom that I'm being taught in my basic chemistry course. In particular, I can't see how a negatively charged electron can stay in \"orbit\" around a positively charged nucleus. Even if the electron actually orbits the nucleus, wouldn't that orbit eventually decay? I can't reconcile the rapidly moving electrons required by the planetary model with the way atoms are described as forming bonds. If electrons are zooming around in orbits, how do they suddenly \"stop\" to form bonds. I understand that certain aspects of quantum mechanics to address these problems, and that there are of atoms. My question here is whether the planetary model itself addresses these concerns in some way (that I'm missing) and whether I'm right to be uncomfortable with it." ]

[ "Creating the Nabla operator (also known as Del operator) as an operator", "Can not create SFTP user Debian 7 I have a linode and I access via ssh throw terminal. I need to create an sftp user which his default directory (and the only he can access) is /var/www/xxxxxx.com/public_html/directory Now, I did it, but when I try to connect I get broken pipe or connection rejected by peer What I did is this: $ adduser --home /var/www/xxxxxx.com/public_html/directory/ username $ chown username:username /var/www/xxxxxx.com/public_html/directory/ $ chmod 755 /var/www/xxxxxx.com/public_html/directory/ $ nano /etc/ssh/sshd_config In /etc/ssh/sshd_config I added the following lines Match User username ChrootDirectory /var/www/xxxxxx.com/public_html/directory/ AllowTCPForwarding no X11Forwarding no ForceCommand internal-sftp What am I doing wrong? EDIT: This is the actual error EDIT2: this is the error in filezilla EDIT 3: auth.log Oct 15 17:47:11 (none) sshd[361]: fatal: bad ownership or modes for chroot directory \"/var/www/xxxxxxxxxxxx.com/public_html/extras_html\"", "What is the fastest way to create a list of directories specified in a file? I have a text file, \"foo.txt\", that specifies a directory in each line: data/bar/foo data/bar/foo/chum data/bar/chum/foo ... There could be millions of directories and subdirectories What is the quickest way to create all the directories in bulk, using a terminal command ? By quickest, I mean quickest to create all the directories. Since there are millions of directories there are many write operations. I am using ubuntu 12.04. EDIT: Keep in mind, the list may not fit in memory, since there are MILLIONS of lines, each representing a directory. EDIT: My file has 4.5 million lines, each representing a directory, composed of alphanumeric characters, the path separator \"/\" , and possibly \"../\" When I ran xargs -d '\\n' mkdir -p &lt; foo.txt after a while it kept printing errors until i did ctrl + c: mkdir: cannot create directory `../myData/data/a/m/e/d': No space left on device But running df -h gives the following output: Filesystem Size Used Avail Use% Mounted on /dev/xvda 48G 20G 28G 42% / devtmpfs 2.0G 4.0K 2.0G 1% /dev none 401M 164K 401M 1% /run none 5.0M 0 5.0M 0% /run/lock none 2.0G 0 2.0G 0% /run/shm free -m total used free shared buffers cached Mem: 4002 3743 258 0 2870 13 -/+ buffers/cache: 859 3143 Swap: 255 26 229 EDIT: df -i Filesystem Inodes IUsed IFree IUse% Mounted on /dev/xvda 2872640 1878464 994176 66% / devtmpfs 512053 1388 510665 1% /dev none 512347 775 511572 1% /run none 512347 1 512346 1% /run/lock none 512347 1 512346 1% /run/shm df -T Filesystem Type 1K-blocks Used Available Use% Mounted on /dev/xvda ext4 49315312 11447636 37350680 24% / devtmpfs devtmpfs 2048212 4 2048208 1% /dev none tmpfs 409880 164 409716 1% /run none tmpfs 5120 0 5120 0% /run/lock none tmpfs 2049388 0 2049388 0% /run/shm EDIT: I increased the number of inodes, and reduced the depth of my directories, and it seemed to work. It took 2m16seconds this time round.", "Prove that $r \\in R$ such that $0 \\lt r \\lt 1$ then $\\frac{1}{r (1 - r)} \\ge 4$", "Hopefully I'm using the right terminology. I'd basically like to know how specific of a location I can make a Pokemon Lure. An Address will not cut it, would need to be like 5ft of my phone or something for it to be useful. I do not currently play the game and am only interested in this to attract new customers similar to, but I wouldn't be in a storefront with an address.", "How to delay or slowly loop commands?", "No \"Login using Google\" option in Android app I registered this ID with my Gmail account, and logged in successfully via web browser. However, while I was trying to log in on the Stack Exchange app in my Android Phone, I don't see any option to log in with Google: I was told that no user was found with my Gmail account. It is amazing that I can log in via web browser, but cannot do so with the same Gmail account via app. How can I do that? Just to compare, here is a \"normal\" login screen of another user: Where did the Google login go and how can I bring it back? My app version is 1.0.73, phone is Coolpad 8150D with Android version 4.0.3, kernel 3.0.8.", "Uniform distribution on the surface of unit sphere", "Is it possible to use JSF+Facelets with HTML 4/5?", "When using \\textsc, LaTeX issues warning: Font shape `OT1/cmr/bx/sc' undefined", "We have been asked to prove the above statement through the two sub-proofs: Firstly we must prove that $e^x$ is increasing and then prove that $\\log(x)$ is also an increasing function. After we are asked to prove that using the delta-epsilion definition of a limit that $\\lim_{x \\to 0} e^x = 1$. I have done all of this but still don't see where the instructor is going with this.", "Does each new Horcrux take half of Voldemort's remaining soul, thus taking a smaller piece each time? When you commit a murder and create a Horcrux, you split your soul. It’s been talked a lot about Voldemort splitting his soul in 7/8 parts. But I think his remaining soul was not 1/7 or 1/8 but far more weaker than that because he did not create all Horcruxes at once. When he created his first Horcrux, his soul was split into 50-50 (diary). But when the second Horcrux was created, it was created by Voldemort only and the first Horcrux soul should have remained intact. Hence it would have been a 25-25 split of Voldemort's main soul. And so on for every split. Am I right?", "What is a lambda (function)?", "What is the Fastest a Character Can Move in One Turn? At level 20 with any magic items in the DMG, and any spells, what is the fastest a DnD 5e character could move using their movement? (i.e., not including teleportation)", "Proper notation for distinct sets Consider I have two sets that neither one is a subset of the other (for example, the set of prime numbers and the set of odd integers). Is there a specific notation that combines the meanings of both ⊄ and ⊅ ? Also, is there a notation to mean that two sets are completely distinct and share no elements in common (for example, the sets of odd and even integers)? ≠ seems very inappropriate, and I'd like to avoid it. Context: My area is actually Computer Science. I'm using this refine my vocabulary in order to teach my students about (which is basically about sets and subsets of IP addresses), and to write some exercises for them. I'll probably use the words incomparable and disjoint as suggested.", "Can you help me with my capacity planning?", "Orthographic Camera Zooming In XNA I am using a spritebatch to render a board. I have created a camera class which can provide me a view and projection matrix. Currently I am supplying the view matrix to my sprite batch when I call begin. I can get the view matrix to correctly move everything around and do some zooming in and out. My problem is that I want to zoom in on a specific point (for now the center of the screen) but currently zooming just zooms in on the coordinate 0,0. Here is how I am constructing the view matrix; _ViewMatrix = Matrix.CreateTranslation( new Vector3( (-_Position.X + _Width * _Zoom / 2), (-_Position.Y + _Height * _Zoom / 2), 0) ) * Matrix.CreateScale(new Vector3(_Zoom, _Zoom, 1)); How could this be altered to make it scale correctly relative to the given point. Later I will probably want to zoom to the mouse position, but if someone has a simple example I'm sure I can work out how to adapt it.", "What is the appropriate statistical test when calculating the busiest day of the week? We have 10 years of data and Monday is the busiest (most visits to the hospital) on average. If we wanted to assess whether that is true and report a p-value, what is the appropriate statistic? We believe the answer is chi-square as we found a peer-reviewed medical article from the Annals of Emergency Medicine (highest circulating journal for that specialty) that used chi-square for this very calculation. If chi-square is appropriate, what values do we use for observed and expected values for chi-square? One approach would be to list all the values for Monday as observed values, or all the means for Mondays averaged across a month, or all the means for Mondays averaged across a year. If there were no busiest or least busy days, we would assume that the visits would be the same every day of the week. That means our \"expected values\" for Chi-Square would be the mean of the visits for any given week.", "The rulebook states that carrying capacity is the strength score times 15 (lbs). Find familiar allows me to get a hawk, which has a strength score of 5. This results in a carrying capacity of 75 lbs. This is well within the range of weights for small people such as gnomes or halflings. Does this mean my familiar can carry them and fly away (given they do not struggle)?", "Gravitational shielding and equivalence principle" ]

[ "Are questions about (development) devices allowed on Stack Overflow? I've seen many questions on Stack Overflow asking which devices are best for developers. This made me wonder if questions asking for hardware device recommendations (best device for programming, best device within a certain budget, etc.) are on-topic for Stack Overflow, or if they should be asked somewhere else? For Instance check these links: etc.", "Why do we need sigma-algebras to define probability spaces? We have a random experiment with different outcomes forming the sample space $\\Omega,$ on which we look with interest at certain patterns, called events $\\mathscr{F}.$ Sigma-algebras (or sigma-fields) are made up of events to which a probability measure $\\mathbb{P}$ can be assigned. Certain properties are fulfilled, including the inclusion of the null set $\\varnothing$ and the entire sample space, and an algebra that describes unions and intersections with Venn diagrams. Probability is defined as a function between the $\\sigma$-algebra and the interval $[0,1]$. Altogether, the triple $(\\Omega, \\mathscr{F}, \\mathbb{P})$ forms a probability space. Could someone explain in plain English why the probability edifice would collapse if we didn't have a $\\sigma$-algebra? They are just wedged in the middle with that impossibly calligraphic \"F\". I trust they are necessary; I see that an event is different from an outcome, but what would go awry without a $\\sigma$-algebras? The question is: In what type of probability problems the definition of a probability space including a $\\sigma$-algebra becomes a necessity? provides a plain English accessible explanation. The idea is a spinning pointer rotating counterclockwise on a circle of unit perimeter: We begin by constructing a spinner, which consists of a circle of unit circumference and a pointer as shown in [the] Figure. We pick a point on the circle and label it $0$, and then label every other point on the circle with the distance, say $x$, from $0$ to that point, measured counterclockwise. The experiment consists of spinning the pointer and recording the label of the point at the tip of the pointer. We let the random variable $X$ denote the value of this outcome. The sample space is clearly the interval $[0,1)$. We would like to construct a probability model in which each outcome is equally likely to occur. If we proceed as we did [...] for experiments with a finite number of possible outcomes, then we must assign the probability $0$ to each outcome, since otherwise, the sum of the probabilities, over all of the possible outcomes, would not equal 1. (In fact, summing an uncountable number of real numbers is a tricky business; in particular, in order for such a sum to have any meaning, at most countably many of the summands can be different than $0$.) However, if all of the assigned probabilities are $0$, then the sum is $0$, not $1$, as it should be. So if we assigned to each point any probability, and given that there is an (uncountably) infinity number of points, their sum would add up to $&gt; 1$.", "How do I evaluate several n-th derivatives of a function at one point?", "Let $x*y=\\gcd(x,y)$ on $D_n=\\{x\\in \\mathbb N:x |n\\}$. I have to prove that $(D_n,*)$ is a commutative monoid and I have a problem when finding the identity element. $x*e=x$ So $gcd(x,e)=x \\to e=xk,k\\in \\mathbb N^*$ and $e \\leq n$ A good $e$ is $0$ but it's not in $D_n$", "What word indicates spatial data within the geographical and geological domains? In particular, what word is precise enough for a science journal article (i.e., formal prose)? Candidates might include &quot;spatial data,&quot; &quot;geodata,&quot; &quot;geospatial data,&quot; and &quot;geographic data.&quot; &quot;Spatial data&quot; seems too generic (not necessarily within the geographical and geological domains). What is the consensus, if any exists?", "I need to set weights for some edges from a python script. I have tried looping through object.data.edges and setting bevel_weight values but I can't get it right. It only works if I have first edited some edge's bevel weight by hand from the 3d-view's transform window. But I would like to get it work from my script without any manual hacking. Steps to reproduce: Start Blender with default cube and switch to Scripting view. Try to set weights for all edges: for edge in C.object.data.edges: edge.bevel_weight = 1.0 Verify that values changed: for edge in C.object.data.edges: edge.bevel_weight Switch into edit mode in 3d-view and open up transform window by pressing n. Select edges to see that the change did not work (bevel weights are all zero). Switch back to object mode and read values again in scripting console to see that they were reset to zero: for edge in C.object.data.edges: edge.bevel_weight Go back to edit mode and change some edge bevel weight straight from the transform window by hand. Go back to object mode and change values again from the scripting console: for edge in C.object.data.edges: edge.bevel_weight = 1.0 This time it works, bevel weights are 1.0 when you go back to edit mode and look from the transform window. Any ideas? My final need is to apply a bevel modifier to only some set of edges and that's why I'm trying to mark them by using weights. Using vertex group for bevel modifier does not work in my situation, since I need to specify edges, not vertices, which to bevel. I'm using Blender v2.71.", "How do I get a file extension in PHP?", "From the limit definition of differentiability, determine where the function $f(x) = \\sqrt{x}$ is differentiable? For the function $f(x) = \\sqrt{x}, \\hspace{2 mm} f: [0, \\infty) \\rightarrow \\mathbb{R}$, I wish to find all points $a$ at which $f(x)$ is differentiable, from the definition $$ f'(x) = \\lim_{x \\rightarrow a}\\frac{f(x)-f(a)}{x-a} $$ Clearly, for our function $f(x) = \\sqrt{x}$, this gives us $$ f'(x) = \\lim_{x\\to a}\\frac{\\sqrt{x} - \\sqrt{a}}{x-a} $$ So the question boils down to showing for what values of $a$ this limit exists. How would this be done? Intuitively, I know that the answer is that the limit exists for all $a \\in [0, \\infty)$ and is given by $\\frac{1}{2 \\sqrt{a}}$, but I'm unsure of how to prove this from the limit definition of differentiability.", "Can anyone explain why a semi-simple finite dimensional Lie algebra $\\mathfrak{g}$ has to be perfect ? The natural way to prove something like that would be to look to the algebra generated by the Lie brackets, which when $\\mathfrak{g}$ is not perfect would be expected to be solvable. But it doesn't seem to work.", "What kind of distribution is this \"almost\" uniformly distributed data for calls/week? My supervisor asked me to find out which distribution represents a particular situation. I have a VoIP generator that generates calls \"uniformly\" distributed between callers. This means that the volume per caller distribution is \"almost\" uniformly distributed between a minimum and maximum. So by running a test with 10000 users and a min value equal to 30 calls per week and a max value equal to 90 calls/week i obtain that not all the users respect this limits: we have some users that generate &lt;30 calls and some other users that generate >90 calls. It is clear that the obtained distribution is not uniform. The situation is this: He said that i have to perform a sort of numerical process in order to find some formulas that could define this distribution. Initially, as wrote before,we wanted to obtain a uniform (min,max) distribution (the green area in the figure) but this is not the case as proved with chi-square test. Moreover the curve in figure is not symmetric, the probability of call generation below 30 call/week and greater that 90 call/week are not identical (it is high for 90calls/week). The variability of the number of generated call increases with the increasing call generation rates. \"Actually implementation of this distribution is nothing but assigning different call rates in a range for users in domain which indicates implementation of several delta functions. As the call rates increases the variability of the generated calls also increases with the average call rate and this leads to the asymmetric behavior of the curve.\" [cit. from the Voipgenerator documentation] Someone can help me?I think that now i cannot use Q-Q plot because i don't know which theoretical distribution i have to use in order to compare it with my empirical data. Sorry if I have stressed with a similar problem a few weeks ago, but initially we thought we could change the implementation, but now we cannot. Hence i have to discover the type of the distribution i obtained and i don't know how can i do this.", "Every subspace of a vector space has a complement I want to see if my proof is true or I thought very trivially? If $H$ is a subspace of a finite dimensional vector space $V$, show there is a subspace $K$ such that $H\\cap K=0$ and $H+K=V$ So far I have tried : $H\\subseteq V$ is a subspace $\\Rightarrow\\,\\exists\\;K=(V-H)\\subseteq V$ $K$ is a subspace because it's the sum of two subspace $V$ and $(-H)$ Now we should prove that $H\\cap K=0$ We assume $H\\cap K\\neq0\\Rightarrow\\exists\\,\\vec u\\neq0\\,,\\,\\vec u\\in H\\cap K$ $\\vec u\\in H\\cap K\\Rightarrow \\begin{cases}\\vec u\\in H\\\\\\vec u\\in K\\,\\Rightarrow\\vec u\\in V-H\\Rightarrow\\vec u\\in V,\\,\\vec u\\notin H\\end{cases}$ That's a contradiction so our hypothesis was wrong and $\\vec u=0$", "Best Azure Service for Large no of SQLServer Databases", "What makes the number of neutrons the number of proton similar?", "Midpoint-Convex and Continuous Implies Convex", "There is no set of all sets.. So there are a few posts about this already, but they skip over the problem I have. The proof of Cantor's theorem elegantly shows that if we consider $f:A\\rightarrow \\mathcal{P}(A)$, the set $B=\\{x\\in A : x\\not\\in f(x) \\}$ by its definition cannot lie in the image of $f$, precluding it from being a bijection - hence power sets have strictly greater cardinality. But now, I thought one (obvious) way to characterise the \"set of all sets\" would be $S=\\mathcal{P}(S)$, as indeed, it contains all possible sets (perhaps here is the problem, but I don't immediately see how using this as a definition for the set of all sets is bad). Now consider simply taking the identity function $i:S\\rightarrow S$. Then $B=\\{x\\in S : x\\not\\in x \\}$ - the set of all sets which do not contain themselves. But this doesn't exist. It's exactly the set of Russell's paradox. If this isn't a set, and so is not in $S$, then the proof no longer offers an obstruction to $i$ being surjective. Each other post I've seen on the matter uses Cantor's theorem to show such a set doesn't exist. My query is to find that something else that must be happening, since I think the proof has issues for this particular set. I'm expecting other issues to arise with the definition $S=\\mathcal{P}(S)$...", "Can I buy PSN games and DLC without giving Sony my credit card info?", "Example (note the case): string s = \"Hello world!\"; String s = \"Hello world!\"; What are the guidelines for the use of each? And what are the differences?", "Any point to downvoting already closed questions? That question of mine was closed a long time ago (relatively, to me at least). However, from time to time I still get downvotes for it. That got me thinking: is there any reason to still downvote closed questions?", "Product rule intuition Can anyone think of an intuitive explanation of the product rule? I'm not asking for a derivation. To me it seems like quite an un-untuitive result, as apposed to the chain-rule (which is ironically harder to derive).", "I would like to know if my brother can fly by United Airlines from USA to El Salvador, and my father, from El Salvador to USA using the same round trip ticket, both of them have the same name." ]

[ "Sampling with replacement or without replacement I'm writing a program in R that simulates bank losses on car loans. Here is the questions I'm trying to solve: You run a bank that has a history of identifying potential homeowners that can be trusted to make payments. In fact, historically, in a given year, only 2% of your customers default. You want to use stochastic models to get an idea of what interest rates you should charge to guarantee a profit this upcoming year. A. Your bank gives out 1,000 loans this year. Create a sampling model and use the function sample() to simulate the number of foreclosure in a year with the information that 2% of customers default. Also suppose your bank loses $120,000 on each foreclosure. Run the simulation for one year and report your loss. B. Note that the loss you will incur is a random variable. Use Monte Carlo simulation to estimate the distribution of this random variable. Use summaries and visualization to describe your potential losses to your board of trustees. C. The 1,000 loans you gave out were for 180,000. The way your bank can give out loans and not lose money is by charging an interest rate. If you charge an interest rate of, say, 2% you would earn 3,600 for each loan that doesn't foreclose. At what percentage should you set the interest rate so that your expected profit totals 100,000. Hint: Create a sampling model with expected value 100 so that when multiplied by the 1,000 loans you get an expectation of 100,000. Corroborate your answer with a Monte Carlo simulation. I'm confused about how to set up this simulation up from a high level point of view and have the following questions: 1. For part A, Should I create a pool of 1000 customers or should I create a larger pool of customers? 2. For part A, when sampling, do I sample with or without replacement? 3. For part B, I'm confused about how to set up the monte carlo simulation. Am I varying the size of the customer pool? 4. For part C, I'm not sure how to set up a sampling model that involves the interest rate. Any advice or guidance would be appreciated. I'm also thinking that if I fully understood the high level concepts for parts A and B, part C might not be such a mystery.", "Is a bivariate function that is a polynomial function with respect to each variable necessarily a bivariate polynomial?", "$E[e_te_s\\Delta B_t\\Delta B_s]$ for $\\Delta B_t$ Brownian motion increments and $e_t(\\omega)$ a measurable function.", "I read recently that if you hold a bullet in one hand and a pistol in the other, both hands at the same height, and subsequently fired the pistol at the same time as dropping the bullet, both bullets would hit the ground at the same time (assuming the fired bullet encounters no obstacles). Is this true, and if so can you explain the reasoning behind it with as few equations as possible? I assume it is essentially that gravity is unaffected by momentum, but it just sounds counter-intuitive.", "Show the post's comments on the \"Suggested Edits\" review interface", "$\\hbar \\rightarrow 0$ in quantum mechanics We often see a limit $\\hbar \\rightarrow 0$ in quantum mechanics and sometimes it's related with symmetry breaking. Can someone briefly write the story behind this limit?", "Which mathematical operation does the right hand rule for current come from? I am currently wondering about the famous . Where does it come from mathematically that when you point with your thumb in the direction of the current, your curved fingers will point in the direction of the $B$-field? In other words, which mathematical operation does it come from? Probably it has to do with some vector product or Stokes theorem application, but I am not quite sure about it.", "Will database replication increase the size of the replicated database? First thank you for your time. We have a SQL Server database that was assigned to be replicated. the original size of the database was 5 GB for the datafile, not the log file. Now after the replication the data file is 4 times bigger around 19 GB. Any pointers to see what could happened will be appreciated. I know sql as developer and some little management but nothing about replication. The performance of the database has been damaged very bad so I am trying to see what need to be done to improve it. I do apologize for my English as well.", "Does a differentiable everywhere function have a continuous derivative? If a function $f$ defined on $[a,b]$ and differentiable everywhere, does it mean that its derivative $f'(x)$ is continuous everywhere on $[a,b]$? My understanding is 'yes'. Because if there were 'a gap' in $f'(x)$, we could integrate back to $f(x)$ and show that where the gap is, there would be a sharp \"angle\" where $f(x)$ is not differentiable.", "How to add custom Modules in magento", "I'm trying to install texlive. I proceeded in the recommended way, as per After hours since initiating the download with install-tl as per instructions in . Hours after intiating the install-tl command, the installation aborted with the following error message: Installing [2507/3271, time/total: 03:01:18/03:46:09]: rec-thy [221k] TLUtils::check_file: removing /tmp/bgLBEx3xxA/o1ankpQviV/rec-thy.tar.xz, sizes differ: TLUtils::check_file: TL=0, arg=7428 TLPDB::_install_package: downloading did not succeed Installation failed. Rerunning the installer will try to restart the installation. Or you can restart by running the installer with: install-tl --profile installation.profile [EXTRA-ARGS] install-tl: Writing log in current directory: /usr/local/src/install-tl-20160728/install-tl.log I have no idea how to implement the crypic instruction install-tl --profile installation.profile [EXTRA-ARGS] because I can't find any information as what the EXTRA-ARGS should be, and google provided no help. So I started again with install-tl hoping it would be smart enough not to start from scratch, but it wasn't, and did start from scratch, meaning another 3 hours. This time it crashed after a few minutes, with Installing [0051/3271, time/total: 04:08/04:30:47]: ae [84k] TLUtils::check_file: removing /tmp/ZLEUeUk8LV/ps7iOTjRWq/ae.tar.xz, sizes differ: TLUtils::check_file: TL=43160, arg=57364 TLPDB::_install_package: downloading did not succeed Installation failed. Rerunning the installer will try to restart the installation. Or you can restart by running the installer with: install-tl --profile installation.profile [EXTRA-ARGS] install-tl: Writing log in current directory: /usr/local/src/install-tl-20160728/install-tl.log Why would the installation crash at different places? Could somebody please interpret these crashes and how to prevent them? If the installation crashes again, is there a way of picking up where I left off? (presumably using the mysterious EXTRA-ARGS?). If all else fails, is there another way of getting a less complete latex installation that will actually work? Thanks very much for any advice?", "Leaflet Customer Marker Changes Position with Scale", "What happens if 2 separate abilities require you to sacrifice a creature?", "How was Loki not crushed by Mjolnir? In the Thor movie, Thor puts Mjolnir on top of Loki at the end of the movie to stop him from moving. Why did this not crush Loki? And if it did not crush him, why could he not just roll out from under it?", "How do I Deserialize this XML document: &lt;?xml version=\"1.0\" encoding=\"utf-8\"?&gt; &lt;Cars&gt; &lt;Car&gt; &lt;StockNumber&gt;1020&lt;/StockNumber&gt; &lt;Make&gt;Nissan&lt;/Make&gt; &lt;Model&gt;Sentra&lt;/Model&gt; &lt;/Car&gt; &lt;Car&gt; &lt;StockNumber&gt;1010&lt;/StockNumber&gt; &lt;Make&gt;Toyota&lt;/Make&gt; &lt;Model&gt;Corolla&lt;/Model&gt; &lt;/Car&gt; &lt;Car&gt; &lt;StockNumber&gt;1111&lt;/StockNumber&gt; &lt;Make&gt;Honda&lt;/Make&gt; &lt;Model&gt;Accord&lt;/Model&gt; &lt;/Car&gt; &lt;/Cars&gt; I have this: [Serializable()] public class Car { [System.Xml.Serialization.XmlElementAttribute(\"StockNumber\")] public string StockNumber{ get; set; } [System.Xml.Serialization.XmlElementAttribute(\"Make\")] public string Make{ get; set; } [System.Xml.Serialization.XmlElementAttribute(\"Model\")] public string Model{ get; set; } } . [System.Xml.Serialization.XmlRootAttribute(\"Cars\", Namespace = \"\", IsNullable = false)] public class Cars { [XmlArrayItem(typeof(Car))] public Car[] Car { get; set; } } . public class CarSerializer { public Cars Deserialize() { Cars[] cars = null; string path = HttpContext.Current.ApplicationInstance.Server.MapPath(\"~/App_Data/\") + \"cars.xml\"; XmlSerializer serializer = new XmlSerializer(typeof(Cars[])); StreamReader reader = new StreamReader(path); reader.ReadToEnd(); cars = (Cars[])serializer.Deserialize(reader); reader.Close(); return cars; } } that don't seem to work :-(", "How to write a LaTeX package that bundles not only .sty and .cls files but also some logos in .pdf or .eps formats? I would like to make a LaTeX package with the following subdirs: tex/latex/common (a common .tex file shared among beamer and letter) tex/latex/resources (lots of pdf and eps files with graphical resources) tex/latex/mybeamer (a custom beamer theme with 5 .sty files) tex/latex/myletter (a .cls file for a letter template) I would like to package these files into a single LaTeX package that users could install in an easy way. I read about the .ins and .dtx files and I can see how to pack the .sty and .cls files but what about the extra graphics - the resources folder which contains several PDF and .eps files?", "When I login to my ubuntu system, it show me this this message, How can I see it any time? I tried to run . .bashrc but it didn't worked. Welcome to Ubuntu 12.10 LTS (GNU/Linux 3.2.0-24-virtual x86_64) * Documentation: https://help.ubuntu.com/ System information as of Sat Jul 13 06:16:35 UTC 2013 System load: 0.55 Processes: 96 Usage of /: 8.1% of 68.74GB Users logged in: 0 Memory usage: 55% IP address for eth0: 198.xx.xxx.xxx Swap usage: 0% IP address for eth1: xxx.1x0.xx.xxx =&gt; There is 1 zombie process. Graph this data and manage this system at https://landscape.canonical.com/ 223 packages can be updated. 134 updates are security updates. Last login: Mon Jul 8 17:47:05 2013", "Attribution alignment and order should be consistent with the website", "I can't boot into a usable system after updates. What should I do? Since some system updates, my machine can no longer boot properly. I am no Ubuntu guru. I do not have a week to spare diagnosing the issue. I just want to retrieve important data from this machine's hard drive and get a working computer again ASAP. What should I do?", "On one of my machines I have a process running called \"whoopsie\". I'm running 12.04 server and never specifically installed anything with this name. Google seems to imply that it has something to with error logs but I'm not finding too much information. The fact that I didn't manually install it and the 3 other servers I checked did in fact have no such running process OR executable made me a bit confused. Does anyone know what the \"whoopsie\" process is? Does anyone know what packages might have installed it? The server is quite plain, it has a LAMP stack, Samba and print servers and the Nagios NRPE plugin, nothing more installed, just standing there being a nice backup-server. Some more info: $ whoopsie -h Usage: whoopsie [OPTION...] Help Options: -h, --help Show help options Application Options: -f, --foreground Run in the foreground and USER PID %CPU %MEM VSZ RSS TTY STAT START TIME COMMAND whoopsie 913 0.0 0.4 24448 2092 ? Ssl May07 0:00 whoopsie and $ sudo cat /etc/passwd | grep whoop whoopsie:x:107:118::/nonexistent:/bin/false" ]

[ "How to install KDE along Unity? I have just installed the latest Ubuntu 14.04 and I would like to install KDE along side my Gnome/Unity that I have now. How can I do this? Thanks!", "How many people can the TARDIS transport? The interior of a TARDIS is much larger than its exterior, but how many occupants can it transport?", "I'm one of those exceptions that deviates from the norm: I run CyanogenMod without any Google apps. Is it possible to download the Stack Exchange Android app .apk directly?", "rake db:migrate doesn't seem to work in production", "Enabling tftpd sudo launchctl load -F /System/Library/LaunchDaemons/tftp.plist Start: sudo launchctl start com.apple.tftpd See logs syslog -w com.apple.xpc.launchd[1] (com.apple.tftpd[30687]) &lt;Warning&gt;: Service exited with abnormal code: 1 Or with log stream --process tftp --level debug Filtering the log data using \"process BEGINSWITH[cd] \"tftp\"\" Timestamp Thread Type Activity PID TTL 2020-01-21 12:35:44.903240+0200 0x5292a Activity 0x6afa0 31479 0 tftpd: (libsystem_info.dylib) Retrieve User by Name 2020-01-21 12:35:44.903949+0200 0x5292a Default 0x0 31479 0 tftpd: recvfrom: Resource temporarily unavailable I also tried to run tftpd directly without launchctl sudo /usr/libexec/tftpd -d -i /private/tftpboot/ with the same results. Earlier I used this configuration and it worked fine. But after some changes (may be OS update) it became broken. Current MacOS version is 10.14.6 (18G2022) How to fix tftpd? Appendix. Configuration file /System/Library/LaunchDaemons/tftp.plist has default content: &lt;?xml version=\"1.0\" encoding=\"UTF-8\"?&gt; &lt;!DOCTYPE plist PUBLIC \"-//Apple Computer//DTD PLIST 1.0//EN\" \"http://www.apple.com/DTDs/PropertyList-1.0.dtd\"&gt; &lt;plist version=\"1.0\"&gt; &lt;dict&gt; &lt;key&gt;Disabled&lt;/key&gt; &lt;true/&gt; &lt;key&gt;Label&lt;/key&gt; &lt;string&gt;com.apple.tftpd&lt;/string&gt; &lt;key&gt;ProgramArguments&lt;/key&gt; &lt;array&gt; &lt;string&gt;/usr/libexec/tftpd&lt;/string&gt; &lt;string&gt;-i&lt;/string&gt; &lt;string&gt;/private/tftpboot&lt;/string&gt; &lt;/array&gt; &lt;key&gt;inetdCompatibility&lt;/key&gt; &lt;dict&gt; &lt;key&gt;Wait&lt;/key&gt; &lt;true/&gt; &lt;/dict&gt; &lt;key&gt;InitGroups&lt;/key&gt; &lt;true/&gt; &lt;key&gt;Sockets&lt;/key&gt; &lt;dict&gt; &lt;key&gt;Listeners&lt;/key&gt; &lt;dict&gt; &lt;key&gt;SockServiceName&lt;/key&gt; &lt;string&gt;tftp&lt;/string&gt; &lt;key&gt;SockType&lt;/key&gt; &lt;string&gt;dgram&lt;/string&gt; &lt;/dict&gt; &lt;/dict&gt; &lt;/dict&gt; &lt;/plist&gt; Update1 It seems port is in use. Why? Who? $ sudo lsof -i:69 COMMAND PID USER FD TYPE DEVICE SIZE/OFF NODE NAME launchd 1 root 23u IPv6 0x55f5dbd8d897c847 0t0 UDP *:tftp launchd 1 root 57u IPv4 0x55f5dbd8d897e687 0t0 UDP *:tftp launchd 1 root 59u IPv6 0x55f5dbd8d897c847 0t0 UDP *:tftp launchd 1 root 60u IPv4 0x55f5dbd8d897e687 0t0 UDP *:tftp launchd uses UDP port 69. Why? $ ps -ef | grep tftp 501 94727 48073 0 4:16PM ttys007 0:00.00 grep --color=auto tftp", "Finding additions and updates between two vector layers using QGIS", "Is the complement of a prime ideal closed under both addition and multiplication?", "Why should the \"H\" option not be used in floats?", "A positional number system for enumerating fixed-size subsets? Many combinatorial objects have some associated positional number system. For example, the subsets of a (finite) set S can be listed off by observing the bits of all $|S|$-bit numbers, treating the 1s and 0s as indicators for whether to pick a particular element or not. Permutations of a finite set S can be found by examining the representations of the first $|S|!$ natural numbers. Is there an analogous positional number system for encoding k-element subsets of an n-element set? Thanks!", "I made the jump from Jumsoft's Money app to GnuCash a while back. It appealed to all my OCD tendencies. I don't know how to use Perl, or stuff of the sort, but with detailed instructions I manage to get things done... when I can find them. I set up Finance::Quote to pull quotes after I set up GnuCash. I even managed to get it to pull quotes for Korean funds. And every thing had been working well, until tonight. I only get back a pop-up that states \"There was an unknown error while retrieving the price quotes.\" That's where I need help. What can I do? I dug around and found that it seems that it has something to do with Yahoo Finance ending it's API support. I also learned that Finance::Quote can pull data from many sources, so I don't really understand why one missing API would break it. I also saw that someone out there is trying to use AEX to pull the quotes instead for GnuCash specifically. I found Finance::Quote on cpan (I also first heard of cpan), but I don't understand what I'm looking at. But that's all beside the point. I don't know how to fix this. Any help would be appreciated. I'm on Windows 10, GnuCash version 2.6.17, and have Strawberry Perl 5.18.2.2-32bit installed. edit Thanks everyone who responded. It seems to be working more or less. The currency and Korean funds still haven't updated, but you've shown this horse to water. I'll do my best to drink it now.", "How to plot ROC curves in multiclass classification? In other words, instead of having a two class problem I am dealing with 4 classes and still would like to assess performance using AUC.", "How can I replay Apache access logs back at my servers to do real world load testing? I looked at but I couldn't see how to replay my own existing logs in any of those tools. I have a bug that only occurs under certain load operations which my existing JMeter and AB testing stuff can't reproduce. I want to simply give the tool access_logs and have it play them back, either faster or at the same speed.", "Is there a GUI IDE for programming python just like java has netbeans? I wanted one where we could drag &amp; drop test boxes &amp; labels just as we do in swing components using netbeans or eclipse. Or is there an add-on present in either netbeans or eclipse itself?", "What type of solder is safest for home (hobbyist) use?", "I want to use input from a user as a regex pattern for a search over some text. It works, but how I can handle cases where user puts characters that have meaning in regex? For example, the user wants to search for Word (s): regex engine will take the (s) as a group. I want it to treat it like a string &quot;(s)&quot; . I can run replace on user input and replace the ( with \\( and the ) with \\) but the problem is I will need to do replace for every possible regex symbol. Do you know some better way ?", "Given the following HTML: &lt;div id=\"container\"&gt; &lt;!-- Other elements here --&gt; &lt;div id=\"copyright\"&gt; Copyright Foo web designs &lt;/div&gt; &lt;/div&gt; I would like #copyright to stick to the bottom of #container. Can I achieve this without using absolute positioning?", "How to disable Ctrl+Shift+U? Ctrl+Shift+U is a combined shortcut in Eclipse. But when I press it, it shows up a u, just like input with an underline. I guess this shortcut has been declared by Ubuntu, so I can't use it. I used to solve this problem by typing Caps Lock first. Is there any better method?", "Density of states for arbitrary dispersion relation If I have a 3D dispersion relation $E=E(k_x, k_y, k_z)$ I have an equation for the density of states, which is $D(E)=\\frac{1}{\\nabla_k E}\\int\\frac{dS}{(2\\pi)^3}$ 1) I am confused about the integral. What am I integrating over, exactly? It must have units of the $k$ vector, so it's a k-space integral, but what is the surface that is relevant? 3) Where does that equation come from, how is it derived?", "Java process memory check test", "With Glade Designer that lets you set up Gtk-Ui's you can check the option that windows are not shown in the launcher. If I take a look at the ui-file generated by Glade, it says &lt;property name=\"skip_taskbar_hint\"&gt;True&lt;/property&gt;. In gtk code this hint is window.set_property('skip-taskbar-hint', True). However I believe that this option is not exclusively Gtk-specific, and want to apply this one on my PyQt4-app. The Ubuntu window manager must be able to receive that hint, otherwise I would see the window of a gtk-application i use (stickynotes-indicator). So there MUST be a way of doing this in Qt or any other language, right? Does anybody know such an option? Python or Qt syntax, doesn't matter!" ]

[ "I am looking for a good source on group theory aimed at physicists. I'd prefer one with a good general introduction to group theory, not just focusing on Lie groups or crystal groups but one that covers \"all\" the basics, and then, in addition, talks about the specific subjects of group theory relevant to physicists, i.e. also some stuff on representations etc. Is Wigner's text a good way to start? I guess it's a \"classic\", but I fear that its notation might be a bit outdated?", "Why is the sample distribution the Exponential distribution Gamma distributed?", "I often have to sort a dictionary, consisting of keys &amp; values, by value. For example, I have a hash of words and respective frequencies, that I want to order by frequency. There is a SortedList which is good for a single value (say frequency), that I want to map it back to the word. orders by key, not value. Some resort to a , but is there a cleaner way?", "I have a Canon 550D with 70-200 f4 and 50mm prime lenses. Although the camera has built-in 9 focal points, I sometimes face a strange problem. Here's a sample photo: In reference to the above pic, you can see that both of the faces are NOT in focus. I used 70-200 f4 for this shot at max aperture. Still, I couldn't get both of them in focus. Why? I also try decreasing the aperture to attain a greater DoF but still, I couldn't get both of them into focus. Another thing: Although the cam has 9 focal points, why can't I use all of them to focus, say, 9 points in a portrait shot? In manual mode, it has the option to select one of the 9 focal points. And in auto mode, it sometimes select more than one focal points. This is just an example image. I've faced this problem zillions of times.", "She put forward two proposals, .......... of which didn’t make any sense to the participants in the summit. The answer for this question in grammar exercises is ‘either’. I am doubtful whether to use either or neither. Can any one clarify this with reason.", "Is there a way to hide pictures from being shown in Gallery", "How to comment lines in rails html.erb files?", "wp_get_nav_menu_items order doesn't work", "Record Animation In BGE", "$n\\in N, a_{n+1} = a_n (1 - a_n)$ , $0 < a_0 < 1$. Prove that $\\lim\\limits_{n\\to\\infty} a_n\\cdot n = 1$. $n\\in N, a_{n+1} = a_n (1 - a_n)$ , $0 &lt; a_0 &lt; 1$. Prove that $\\lim\\limits_{n\\to\\infty} a_n\\cdot n = 1$. I proved that $\\lim\\limits_{n\\to\\infty} a_n = 0$ and that $a_n$ is strictly decreasing. I tried Cezaro Stolz but didn't get anywhere. Thanks in advance.", "Removing trailing newline character from fgets() input", "'setenv' command not working on tcsh shell when called explicitly I can run setenv command just fine in my tcsh shell like this: echo $0 /usr/bin/tcsh echo $SHELL /usr/bin/tcsh setenv START_TIME `date +%s` echo $START_TIME 1499355967 But, whenever I run it explicitly like shown below, it doesn't work. I need to do this because I have to specify shell when executing it via python subprocess call, otherwise it will call a sh shell as default. /usr/bin/tcsh -i -f -c 'setenv START_TIME `date +%s`' echo $START_TIME START_TIME: Undefined variable. What's the problem here? I searched for this issue online, but couldn't find any issue similar to this. This is extremely frustrating.", "What is the strict aliasing rule?", "Bug Identification: Tiny Bugs I have seen these on my hands recently and I am wondering what they are. Urban Setting. South Central Pennsylvania.", "This is my first question in /photography. I'm a very amateur photographer, doing things wrong and by eye with lots of trial-and-error all the time. I currently own a reflex Nikon D70 my uncle gave us after he bought a better one. It has some nice settings, and he bought a a Nikkor 28-80mm F/3.5-5.6 zoom lens for it. It behaves nicely, but it's getting old (it has those old cartridges before SD cards existed) and every new charge takes longer than the last. I'm planning to upgrade to a better camera, and there are some neat offers on a nearby superstore (MediaMarkt), this one catching my eye: Sony DSC-H400 63x, Sensor Super HAD 1/2/3 CCD 20.1MP -> for less than 300€ taxes included I don't have any type of extra information aside from that, all I can get from the official site is clinical data from other cameras that I suspect it's not 100% accurate, and there's no photography expert on the store to ask. The common things I use my D70 for are: taking pictures of scenery (castles, towns, forests, waves hitting rocks, etc...), nearby (&lt;5m) persons and objects, and well, things where I want to save a memory in digital format, not for professional purposes at all. Being that my objective is to have a decent, good-zooming (superzoom looks awesome), amateur (but with manual settings) camera, is this Sony a good replacement? Will I miss any features? Is there any better, similarly-priced alternative you know of? Basically, I want to know whether I will get better quality photos than I currently do, given the examples, with any averagely-priced bridge camera similar to that Sony, and if it's worth it. examples of current camera results Full zoom-out of town at night, bad quality I know; notice the pink blur at the left. Maximum zoom on that pink blur from almost the same spot: Daylight, cloudy, modified with Adobe Lightroom, scenery: Same day, same beach, different settings: Same day, same beach, rocks:", "Breaking an equation cluster that does not fit on the rest of page across two pages", "Page title with substitution on views page I have a view page that requires a dynamic page title. It is a simple substitution of the label field. If I use {{ label }} it works fine for the title displayed on the page, but it doesn't substitute the label for the actual page title (in meta) I was able to fix this by using hook_views_post_render using the following code // Set the route title. $route = \\Drupal::routeMatch()-&gt;getCurrentRouteMatch()-&gt;getRouteObject(); $route-&gt;setDefault('_title', $title); $view-&gt;setTitle($title); However, the title only works if the page is not cached. For the cached pages, the page title is missing. This feels like a bug in drupal, but I am hoping that there is a simple way to get this done.", "Let be $V$ a vector space over the complex numbers with inner product. Let be $T$ and $S$ linear operators in $V$ with adjoint operators $T^*$, and $S^*$ respectively. I know that it satisfies this: $\\left&lt; T(x),y \\right&gt;=\\left&lt; x,T^{*}(y) \\right&gt;$ $\\left&lt; S(x),y \\right&gt;=\\left&lt; x,S^{*}(y) \\right&gt;$ $\\forall x,y \\in V$ But, How can I prove that the adjoint operator of $ST$ is $(ST)^{*}$? And how can I prove that $(ST)^{*}=T^{*}S^{*}$?", "What are the differences between $$, \\[, align, equation and displaymath?", "I think there's an unintended motivation for users to post questions to higher-traffic Stack Exchange sites rather than their more specific or appropriate lower-traffic ones. I think I have a solution. What motivated this suggestion for me was that I am confident that if users were to post Android design questions to beta and/or , that they would likely not be noticed by the appropriate audience compared to the vast army of Android experts here on Stack Overflow. There are plenty of Android questions on SO that really should be on one or both of the aforementioned sites. Presently there is little motivation for users to start questions like this on the appropriate site. Is there something we could do to cross-pollinate related sites? For instance, what if we let certain tags span certain sites? Obviously the selection would be controlled by high-reputation users. There could also be a feature to show (or explicitly hide) certain questions from other sites regardless of the tags. This could be controlled by lower-reputation users than the global tag since it wouldn't have much statistical impact. For instance, the android-layout tag could by default span sites, but OPs and other users could eliminate from the Graphic Design site questions that are of a purely technical nature. Users interested in Android tagged questions would see related questions on design and UE sites--whether they are searching, posting, or viewing a question through the related items. This would help eliminate cross-site duplicates, and encourage people to post on the correct site in the first place. For related question lists and search results, there could even be a specific cross-site icon next to an off-site question to show that it's from UX, for example." ]

[ "What do parentheses surrounding an object/function/class declaration mean? I'm new to both JavaScript and . In YUI library examples, you can find many uses of this construct: (function() { var Dom = YAHOO.util.Dom, Event = YAHOO.util.Event, layout = null, ... })(); I think the last couple of parentheses are to execute the function just after the declaration. ... But what about the previous set of parentheses surrounding the function declaration? I think it is a matter of scope; that's to hide inside variables to outside functions and possibly global objects. Is it? More generally, what are the mechanics of those parentheses?", "AmpScript to select Right or Left characters from a string Is there an AmpScript function that can be used in an equivalent manner to sql left, right and mid functions? Thanks, Mark", "Create WiFi hotspot on ubuntu", "Are there fewer positive integers than all integers? In our 6th grade math class we got introduced to the concept of integers. With all the talk about positive and negative, it got me wondering. Is the amount of elements in $\\mathbb{Z^+}$ less than the amount of elements in $\\mathbb{Z}$? Here is how I thought of it. If we have $\\mathbb{Z^+}$ and add one element to the \"back\" of it ($\\mathbb{Z}^{\\geq-1}$) there are certainly more elements in that new set, so there must be more elements in $\\mathbb{Z}$ than in $\\mathbb{Z}^+$ but on the other side if we try to express the amount of elements in them \"numerically\" (In a loose sense of the word) they both have $\\infty$ elements. So what is the right answer? Is there even one? (Please note I am a bit of a layman when it comes to mathematics) Edit: About the possible duplicate, I am not looking for a bijection between the two sets, I am looking for if they even have the same number of elements and why a bijection shows that they do/don't", "I have recently been reading about Quantum Electrodynamics which I found very interesting, but even more confusing. I understand photons mediate the electromagnetic force and interactions between charges can be described by virtual photon exchange. And that in Quantum Mechanics particles paths can be evaluated by sum over all paths... An electron travelling from one point to another will take all paths, emitting and reabsorbing virtual photons. Does the electrons take all paths including those that involve faster than light velocities? Is this question null, Does it mean anything to ask about properties of virtual particles? Do I have the wrong idea about what virtual particles are?", "Is the set of all possible binary strings countable? Determine whether the given sets are countable or uncountable. Justify your answers either with bijections or using results/methods. The set of all possible binary strings. Note a binary string is a sequence of 0s and 1s. If a binary string consists only of 0s and 1s, then is it even possible to find a bijection for it?", "How to create a soft or symbolic link?", "Where in Europe can I purchase a car without residency? I am not a resident anywhere and plan to travel for the foreseeable future, mostly in Europe. My country has good visa-free access to most of Europe, so it is conceivable I could remain without any residency for quite some time. I enjoy driving, and maintaining cars, and I would like to purchase a car somewhere in Europe. Where, if anywhere, in Europe (or outside of Europe, but with the ability to drive the car in Europe) can I legally purchase and insure a car as a non-resident? I am open to creative solutions like setting up a company to own the car, if the capital and ongoing paperwork requirements for the company are not too onerous. I am aware that I could save money, get places quicker, etc, by taking trains or flying. I have a passion for cars and driving. Suggesting that I not buy a car is out of scope of this question.", "What does 5' and 3' mean in DNA and RNA strands? What are 5' and 3' in DNA and RNA strands? Please clarify with some images and please use simple English.", "Pass commands as input to another command (su, ssh, sh, etc)", "Prove $\\sin^2\\theta + \\cos^2\\theta = 1$ How do you prove the following trigonometric identity: $$ \\sin^2\\theta+\\cos^2\\theta=1$$ I'm curious to know of the different ways of proving this depending on different characterizations of sine and cosine.", "Can the editor for editing tag descriptions get updated to match the normal questions/answers editor? The text editor that is shown when editing tag descriptions still uses the previous behaviour for inserting links and images. Also, the placeholder text for links is still http:// instead of https:// compared to the new editor. Another &quot;nice to have&quot; feature that exists in the main editor is the ability to paste an image from clipboard directly to the text editor without having to press the &quot;insert image&quot; toolbar-icon first. Can it get updated to match the editor we use for questions and answers? The following screenshot is an example of how it looks if I try to insert a link for a tag description: In comparison, this is how it looks in the new editor:", "Convert string to Title Case with JavaScript Is there a simple way to convert a string to Title Case? E.g. john smith becomes John Smith. I'm not looking for something complicated like , just (hopefully) some kind of one- or two-liner.", "This is difficult for me to explain, but how do I put words over a symbol? For instance, I want to add words over an equal sign. Anyone know the command/syntax for that? Also adding ^ doesn't cut it..., I want the text to appear ON TOP.", "How to invite friends to Stack Overflow, Server Fault and Super User? Since we're all into this OpenID thing, I think it would be really useful (and quite easy) to implement a friend invitation feature that grabs a list of friends from one's webmail contact list with an option to choose who to invite to SO, SF or SU. Something in the line of Facebook's friend invitation and recommendation feature.", "How can one differentiate between Dr. (PhD) and Dr. (MD or DO)?", "I have a very simple question. When I do this: \\catcode`\\@=0 \\catcode`\\\\=11 @mycommand{a} @catcode`@\\=0 \\catcode`\\@=11 It works perfectly and calls \\mycommand correctly. However, when I try to define \\mycommand with similar trickery: \\newcommand\\mycommand[1]{ \\catcode`\\@=0 \\catcode`\\\\=11 @textbf{Hello #1} @catcode`@\\=0 \\catcode`\\@=11 } compilation stalls and gives me the * prompt. If I give it Ctrl+D, it terminates without producing any output. Indeed, it seems that changing the catcodes inside a command has no effect whatsoever, because the following works perfectly (whereas, from my understanding, it shouldn't): \\newcommand\\mycommand[1]{ \\catcode`\\@=0 \\catcode`\\\\=11 \\textbf{Hello #1} } Can anybody please explain to me what's happening?", "How does carbon dioxide or water vapour absorb thermal infra red radiation from the sun? We are all told at school water vapour and carbon dioxide are the top two greenhouse gases, and that they absorb thermal infra red radiation, trap heat and warm up the Earth. My question is how do they do that? Why can't Oxygen or Nitrogen or any other gas not absorb infra red radiation as well as water vapour or CO2?", "I am looking for a injective cochain map $\\psi: C^*\\rightarrow D^*$ such that the map $\\Psi^i$ from $C^i$ to $D^i$ is injective, but the map $\\psi^*$ from $H^i(C^*)$ to $H^i(D^*)$ is not injective for any $i\\geq0$.", "I just asked my first question on stackoverflow and I'm really impressed that my question seems to be answered sufficiently already! See: The issue I have is that the last two answers combined would provide the most complete answer. What's the proper way to go about combining them, marking the question answered, and giving credit where credit is due? Thanks big time guys for saving us all from experts exchange hell! Edit: Wow, 5 responses in 5 minutes. I think what makes the most sense is that I create my own answer out of the two. I don't think the second part of my question was answered though. What is the proper way to give credit to the 2 answers that I'm combining? Is an upvote for each sufficient?" ]

[ "Recommendations on a free library to be used for zipping files I need to zip and password-protect a file. Is there a good (free) library for this? This needs to be opened by a third party, so the password protection needs to work with standard tools.", "Reference sObject Fields dynamically from a string value Is it possible to reference the fields of an sObject (opportunity in this example) dynamically from a string value? For example, take the following code: for(Opportunity o: oppList) { for(String s : strList) { // I'd like to set the opportunity field values based on the string // value that contains the API name of the opportunity field } } So, the variable strList contains the opportunity API field names. I'm trying to clear some fields on the opportunity in a before update trigger, but I have to access the field names dynamically in the strList.", "Why should we typedef a struct so often in C?", "How do you use plural or singular form of an adjective? So I was taught that you should almost always use singular form of an adjective instead of plural form. But recently, I've seen people using plural form and it sounds quite weird and I don't know if it is correct. For example, \"Salary tax\" instead of \"Salaries tax\" \"Office supplies\" instead of \"Offices supplies\" \"Product demo\" instead of \"Product demo\" In the above cases, the word \"Salary\" is used as an adjective to describe the type of \"tax\", so it will be in singular form. But I saw people using salaries tax and not sure if it is grammatical. So my question is if there are any general rules on how to use the singular/plural form of an adjective?", "Arriving at a different port of entry in the same state in USA? I am a girl in my early twenties traveling to USA from India and in my visa application I have provided the contact address for a relative in San Francisco, and their invitation letter. I would like to visit LA first. Will I face problems during immigration if I land in LA (with an immediate on wards ticket to SF)? I dont plan to get on the flight from LA to SFO. Initially I was planning to fly to SFO from India and then fly to LA immediately after completing immigration at SFO airport.", "How to Combine two Normal Maps? I made a high poly model and then baked its textures onto a low poly model. Now I want to give another normal map's details to the model. How can this be done?", "Which one is correct: '3 hour journey' or a '3-hour journey'? Which one of the following is correct (bold part)? It took us quite a long time to get here. It was 3 hour journey. or It took us quite a long time to get here. It was a 3-hour journey.", "How do I backup and restore SMS Messages? How do I backup and restore SMS Messages?", "Adding new ROLES and USERS through REST in GeoServer I use GeoServer stable version 2.14.1 and get error messages when trying to add new roles and users via REST. I suspect that the GeoServer REST documentation is buggy. When I call the REST interface of my GeoServer instance, I can see that the roles are accessible through the URI http://localhost:8080/geoserver/rest/security/roles. Users are under the URI http://localhost:8080/geoserver/rest/security/usergroup/users. I can query both resources via GET request, but adding new resources via POST or PUT will not work. A POST request to create new roles ends up with status code 405 (Method not allowed). After trying to create new users comes the status code 500 (Internal Server Error). For this, the GeoServer-REST documentation has been referencing the paths /roles/roles/{role} for new roles () or /usergroup/users/ for new users () since several GeoServer versions. But when I use them, this always ends with Status code 404 (Not Found). How can I add new roles and users through REST in GeoServer? The workarround from @implssv in does not work for me.", "Does tourist visa (90 days) apply after a long-term visa ends in Schengen countries?", "Local hyperlinks broken after PDF processing with Ghostscript I usually compress my tex PDFs with ghostscript: pdflatex -shell-escape file.tex gs -sDEVICE=pdfwrite \\ -dCompatibilityLevel=1.4 \\ -dPDFSETTINGS=/prepress \\ -dNOPAUSE -dQUIET -dBATCH \\ -sOutputFile=file_compressed.pdf \\ file.pdf Normally that works well, but if I have relative links to local files, the links don't work afterwards. Minimal example: \\documentclass{beamer} \\usepackage{hyperref} \\begin{document} \\begin{frame} \\href{run:./audio.mp3}{test} \\end{frame} \\end{document} The link works in file.pdf but not in file_compressed.pdf. Is there any pdflatex or ghostscript setting that retains the link in the compressed version? I use Acrobate Reader 10.1.14 for viewing, Ghostscript 9.10 and pdfTeX 3.14159265-2.6-1.40.15 (TeX Live 2014) on OS X 10.9.5. Update: The breakage of hyperlinks had nothing to do with compressing the PDFs. The breakage happened for all re-processing of PDFs containing hyperlinks in its input PDF.", "A word with a wide range of meanings Is there a better alternative to ambiguous for a word with a wide range of meanings, difficult to find, because they become different in connection with person's opinion.", "I know and I have proved more than once that the set of irrational numbers ($\\mathbb{I}$) is uncountable, but now I'm given to solve this problem: Show that $|\\mathbb{I}|=|\\mathbb{R}|$, How can I do that? Do I need to assume the Continuum Hypothesis in order to that statement to be true? Thanks", "Control a property with no socket (color ramp swatch, etc) from a Group Node input?", "A group $G$ with a subgroup $H$ of index $n$ has a normal subgroup $K\\subset H$ whose index in $G$ divides $n!$", "An insurance company supposes that the number of accidents that each of its policyholders will have this year is Poisson distributed, with a mean depending on the policyholder: the Poisson mean Λ of a randomly chosen person has a Gamma distribution with the Γ(2, 1)-density function fΛ(λ) = λe−λ (λ > 0). Find the expected value of Λ for a policyholder having x accidents this year (x = 0, 1, 2, . . .). I am not sure how to incorporate the gamma parameters. So far I have found P(X = n|Λ = λ) = Poisson(λ) and fΛ(λ)= Exp(λ) so by integrating P(X = n|Λ = λ)fΛ(λ) then letting the integral of Gamma (n + 2, 2) equate to 1, I have worked out P(X = n) = (n + 1)/2^(n+2). How do you find the expected value of Λ from that? I have seen that a Gamma-Poison mix has E(X) = αβ which would give 2 but I have tried integrating fΛ(λ) and can't seem to get 2.", "Suppose the gcd (a,b) = 1 and c divides a + b. Prove that gcd (a,c) = 1 = gcd (b,c) I am lost. So far... If $\\gcd (a,b) = 1$, by Bezout's Formula $ax + by = 1$ If $c|(a+b)$, then $cf = a+b$ Then, $a (x-y) + cfy = 1$ $b(yx) + cfx = 1$ Am I on the right track? Any suggestions?", "My site as of right now is a static website. I am planning on having a 'recent blog posts' section on it, with permalink to the main blog post/blog. example: http://site.com/blog I was wondering, because of having a recent blog posts section on the homepage, should I just have the entire website powered by WordPress and just add the homepage (and other pages, such as contact) as a word press 'page', and call recent blog posts on it? If I do it that way, am I still able to have the blog in /blog? I was also thinking of just adding the whole WordPress files to the /blog directory and call recent blog posts from the static file... I am new to Wordpress, so I am a bit confessed here. What is the best option?", "Will be supported on the Android App in the future? I visit A51 rather frequently and I would like to see it in the App.", "A cop vs a superhuman criminal I read the story over ten years ago while I was still trying to learn English, so I can only vaguely remember that the story is about a cop trying to track down a criminal who had superhuman abilities. Some of his abilities were pyrokinesis, using his mind to form a golem from earth and roam around while he stays in the room and stopping time. Eventually the cop was able to catch the criminal and shot him dead. If anyone could identify the book I would be very grateful. I'd love to read it for nostalgic purposes." ]