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I'm 100% sure I saw about HDMI which may not have been asked more than 4 hours ago, but it was not in the result list when I entered HDMI in the search field. Then I noticed: when I enter "HDMI" as search term, it searches for the tag instead. Is this the expected behavior? And is it really my task to find out that I have to enter "HDMI" to get other results? Can we at least have an indicator that some magic happened, e.g. You entered HDMI. We're looking for questions tagged instead. Search for "HDMI" instead. | Asume the following search queries: osx, cocoa, iphone, xcode, applescript, mac, carbon Searching for osx, cocoa, iphone or xcode like: http://stackoverflow.com/search?q=osx Results into searching by tag: http://stackoverflow.com/questions/tagged/osx While searching for applescript, mac and carbon like: http://stackoverflow.com/search?q=applescript Results into searching by string. Yes, I know how to search by tags using brackets: [applescript] But why are the queries above interpreted differently? All queries are valid Stack Overflow tags! Why not convert all queries into search by string or search by tag? What is the logic behind? Tag popularity? It seems rather inconsistent to me. |
Let $A$ and $B$ are Riemann surfaces. $f:A→ B$ is morphism of Rieman surface, in other word, holomorhic function, and supposed that $f$ is bijective. Then, can we say that inverse of $f$ is also holomorphic? Thank you in advance. | I'm confused about the following proposition Proposition. Let $U,V$ are open sets in $\mathbf{C}$. If $f:U\to V$ is holomorphic and bijective, then the inverse $f^{-1}:V\to U$ is also holomorphic. The proof of the proposition think that the continuity of $f^{-1}$ is obvious, but I find it is really difficult to prove using $\epsilon-\delta$ definition. Can anyone give some hints? |
I would like to know how to count the characters in every line in a text, then subtracting this number from a threshold represents the maximum number of characters allowed per line, after then I would like to fill the gaps between the maximum number of characters and the count of characters with dots. For example: Unix was originally meant to be a co nvenient p latform for progra mmers developing software to be run on it and on other systems, rather than for non- programmers. [7][8] The system grew larger as the operating system star ted spreading in a cademic circ les, as users add ed their own tools to th e system and shared them wi th colleagues. The maximum number of characters over all the lines is /31/ in line#11. I would like the count of characters in every line to be /31/ by filling the empty spaces with dots, like this: Unix was , ..................... originally meant , ............. to be a , ...................... co, ............................ nvenient p, .................... latform for progra, ............ mmers developing software to, .. be run on it and on other , .... systems, rather than for non-,.. programmers., .................. [7][8] The system grew larger,.. as the operating system star, .. ted spreading in a, ............ cademic circ, .................. les, as users add, ............. ed their own tools to th, ...... e system and shared them wi, ... th colleagues., ................ How can I do that in bash? | I'd like to output hello world over 20 characters. printf "%-20s :\n\n" 'hello world!!' # Actual output hello world!! : # Wanted output hello world!!========: However, I don't want to complete with spaces but with "=" instead. How do I do that? |
I have a memory from my childhood of an animated film about a utopian culture. The protagonists and the female supporting character discover that their society is managed by mutated humans. The mutants do all the labor, and this is hidden from the rest of the community. The couple who discover that the underlying society is unjust rebel along with the mutants, but find a giant brain that created the social structure that they cannot defeat. This brain puts the protagonist to sleep under the sea for two thousand years with a large black poisonous thorn. His mission, when he awakes, is to kill the brain with the thorn. Two thousand years later, the hero awakens to find the brain created a new world with an army of robots. He has to defeat them. Eventually, the brain and the hero meet. The brain is much older and shows signs of atrophy. The hero kills the brain by stabbing it with the black thorn. It may be possible that I watched two movies that day and melded them together. I've asked my father about this, but he has no recollection. I've gone to comic shops and discussed the plot with salespeople, to no avail. I search the internet. Nothing comes up that is similar to my description of this film. Perhaps you can help. The film could not have been produced later than 1990. My guess is that the date range to be considered is from the 1970s to the 1980s. My best guess is that the origin of this animation is European. The subject matter, as I infer, relates to the Soviet Communist occupation. The large brain represents the authoritarian Communist regime that Europeans feared in the mid to late 1900s, and the protagonist represents the liberator of the machinery it builds. There are many films from France with this subject matter and themes relating to the social commentary of a utopian culture. | It was a weird sci-fi animated movie I saw only a little bit of it. This is what I recall: It was old but had color, so I assume it was late 1960s to early 1970s. The animation and style reminded me of but it wasn't as psychedelic. The setting was an alien planet with all sorts of bizarre creatures. The tech was advanced but not a dominant aspect of the planet's culture. The people lived simple and peaceful. The protagonist is a man with bluish skin like the others. The antagonists were humanoid shaped black robots that shot a beam that would turn people into stone. |
You used to be able to click "manage this page", but Google has removed that. Then you had to go to "Google My Business" and you could edit your pages from there, but now Google has removed that as well. How do we edit our Google+ Pages now? | I'm the admin of a Google+ Business Page. If I post to it from my Google+ profile by choosing it from the circle drop-down menu, the posting shows as John Doe Shared a post with you instead of normal post entry. Is there a way to post to a Google+ Business Page from a Google+ Profile? |
I have a 64 bit processor but a 32 bit version of Windows 10 and none of the downloaded versions of 2.90.1 will install. Minimum requirements are listed as 'x64 architecture' but I'm not clear if that is x64 processor or x64 OS or both. Thanks. | Will there be a version of blender 2.81 for 32bit windows as there was for 2.80? In my working environment we are currently unable to upgrade PCs. |
When I add this code: otionHover = false; if(optionRect.contains(Mouse.getX(), Mouse.getY())) { otionHover = true; if(Mouse.isButtonDown(0)) { System.out.println("The button was pressed!"); } } I get the error: Exception in thread "main" java.lang.NullPointerException at lt.CobaltPlanet.nelixus.state.GameMenu.init(GameMenu.java:26) at lt.CobaltPlanet.nelixus.Main.initStatesList(Main.java:55) at org.newdawn.slick.state.StateBasedGame.init(StateBasedGame.java:164) at org.newdawn.slick.AppGameContainer.setup(AppGameContainer.java:393) at org.newdawn.slick.AppGameContainer.start(AppGameContainer.java:317) at lt.CobaltPlanet.nelixus.Main.main(Main.java:74) | What are Null Pointer Exceptions (java.lang.NullPointerException) and what causes them? What methods/tools can be used to determine the cause so that you stop the exception from causing the program to terminate prematurely? |
Edit: This is not a duplicate question. My function is different and doesn't use direct object comparison methods. I am working through Eloquent Javascript book and in the fourth chapter, the last exercise required a function deepEqual that takes two arguments and compares them. If the arguments are different types, it should return false. If the arguments are the same type and same value, it should return true otherwise, return false. If the arguments are both objects, their properties and values should be compared. The function call should return true if both objects have same properties and value in the same order. For example, if we have the following objects: object1 = {a: 1, b: 2}, object2 = {a: 1, b: 2}, object3 = {a: 2, b: 1}, comparing object1 and object2 should return true, but comparing object1 and object3 should return false. Lastly, if the objects have nested objects as parameters, a recursive call of deepEqual to compare the nested objects. So, here is my solution. It is quite convoluted with if/else statements, pardon it. function deepEqual(obj1, obj2){ var checkForSameTypes = (typeof obj1 === typeof obj2); if(checkForSameTypes === true){ //same type but not objects if(typeof obj1 !== "object" && typeof obj2 !== "object") { if(obj1 == obj2){ return true; }else{ return false; } // same type and objects }else if(typeof obj1 === "object" && typeof obj2 === "object"){ //loop first object and compare properties with 2nd object for(var prop in obj1){ if(obj2.hasOwnProperty(prop)) { //if 2nd object has property "prop" compare if(typeof obj1[prop] === "object" && typeof obj2[prop] === "object"){ //recursive call deepEqual(obj1[prop], obj2[prop]); }else if(obj1[prop] === obj2[prop]) { //loop goes on to the next property continue; }else if(obj1[prop] !== obj2[prop]){ return false; } //it doesn't have property "prop" so return false } else { return false; } } //finishes loop and all properties are the same return true; } // they are not the same types so return false } else { return false; } } PROBLEM The function works fine except when an argument is an object with nested objects. Take these objects for example var type = {go: {inside: "yes"}, come: 2} var see = {go: {inside: "no"}, come: 2} var fine = {when: 3, go: 4};` When I compare type and see with a call to deepEqual(type,see);, this returns true which is wrong because the value of the property of the nested object go is different. I have gone through the entire code on paper, line by line and do not know what I have to do, or if the recursive call isn't working to compare the properties rightly or I just don't have the knowledge yet. Can anyone offer a solution? or and if possible a better way or thinking process to solve this case? Note: The code only compares object properties and values. It doesn't need to compare constructors or prototypes. | A strict equality operator will tell you if two object types are equal. However, is there a way to tell if two objects are equal, much like the hash code value in Java? Stack Overflow question is similar to this question, but requires a more academic answer. The scenario above demonstrates why it would be necessary to have one, and I'm wondering if there is any equivalent solution. |
So at the moment I have something like: \documentclass[twoside, a4paper, 11pt]{article} \title{} \author{} \usepackage{ragged2e} \usepackage{booktabs,tabularx} \usepackage{amsfonts} \usepackage{amsthm} \usepackage{mathtools} \usepackage{verbatim} \usepackage{amsmath, amssymb} \usepackage{natbib} %\def\pgfsysdriver{pgfsys-dvipdfm.def} \usepackage{tikz} \usepackage{enumerate} \usetikzlibrary{matrix, arrows} \usepackage{graphicx} \usepackage{subfig} \usepackage{listings} \usepackage{color} %\usepackage{hyperref} \usepackage{float} \usepackage{multicol} \usepackage{booktabs} \usepackage{lscape} \usepackage{cases} \usepackage{multirow} \usepackage[figuresright]{rotating} \usepackage{setspace} \usepackage{lscape} \usepackage{longtable} \usepackage{caption} %\usepackage{subcaption} \usepackage[update,prepend]{epstopdf} %\usepackage{mathpazo} %\usepackage{eulervm} %\usepackage{iwona} \usepackage[pdftex,colorlinks,linkcolor=black,citecolor=blue,urlcolor=black]{hyperref} \usepackage[official]{eurosym} %\usepackage{MinionPro} \setlength{\textwidth}{6.5in} \setlength{\oddsidemargin}{0in} \setlength{\evensidemargin}{0in} \setlength{\parindent}{0pt} \setlength{\parskip}{1ex plus 0.5ex minus 0.2ex} \linespread{1.5} \usepackage[top=2.5cm, bottom=2.5cm, left=2cm, right=2cm]{geometry} \begin{document} The most standard approach to modeling default risk centres upon \cite{merton74}'s structural model. \bibliographystyle{apa-good} \bibliography{bibliography} \end{document} The entry in bibtex is: @article{merton74, author = "Merton, R.", title = "{``On the Pricing of Corporate Debt: The Risk Structure of Interest Rates''}", year = "1974", journal = "The Journal of Finance", volume = "29", number = "", pages = "449--470"} The output is like: However I would like the 's to appear right after Merton, ie, Merton's (1974). How can I achieve this? | Is there an automatic way to attach a genitive apostrophe or " ' s " to an author's name? Currently I use: \citeauthor{kuran1989}'s \citeyear{kuran1989} But since this comes up regularily I'd like to know whether there's a general solution. |
I shifted from windows to ubuntu for first time on HP r-15 laptop and dual booted ubuntu 14.04 LTS with windows 8.1.But i am having problem with wifi.I can connect to wifi without any problem but after a while it randomly stops working but it is showing that i am connected.When i try to reconnect,it looks like it is trying to reconnect but never do.Only solution for this is to reboot the laptop and everything starts working fine for some time. I read some same questions like that but that are none of my use. I am a beginner in linux. Thanks for help in advance.Edit - this was the output of the command suggested by Pilot6 0a:00.0 Network controller [0280]: Realtek Semiconductor Co., Ltd. RTL8723BE PCIe Wireless Network Adapter [10ec:b723] Subsystem: Hewlett-Packard Company Device [103c:2231] Kernel driver in use: rtl8723be | I have installed Ubuntu 15.04 on my laptop with RTL8723BE Wi-fi card. But it is always disconnecting from network. I have tried echo "options rtl8723be fwlps=N ips=N" | sudo tee /etc/modprobe.d/rtl8723be.conf but that didn't helped. What can I do to prevent the wifi from disconnecting? If I upgrade to kernel 4.X, will it help? ~$ lspci -knn | grep Net -A2 09:00.0 Network controller [0280]: Realtek Semiconductor Co., Ltd. RTL8723BE PCIe Wireless Network Adapter [10ec:b723] Subsystem: Hewlett-Packard Company Device [103c:2231] Kernel driver in use: rtl8723be ~$ rfkill list 0: hci0: Bluetooth Soft blocked: yes Hard blocked: no 1: phy0: Wireless LAN Soft blocked: no Hard blocked: no ~$ ifconfig && iwconfig && route -n && ping -c 1 google.com eth0 Link encap:Ethernet HWaddr 38:63:bb:cd:4a:7e UP BROADCAST MULTICAST MTU:1500 Metric:1 RX packets:3 errors:0 dropped:0 overruns:0 frame:0 TX packets:53 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:752 (752.0 B) TX bytes:8445 (8.4 KB) 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:3870 errors:0 dropped:0 overruns:0 frame:0 TX packets:3870 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:314613 (314.6 KB) TX bytes:314613 (314.6 KB) wlan0 Link encap:Ethernet HWaddr c0:38:96:6d:c4:83 inet addr:192.168.1.205 Bcast:192.168.1.255 Mask:255.255.255.0 inet6 addr: fe80::c238:96ff:fe6d:c483/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:15240 errors:0 dropped:0 overruns:0 frame:0 TX packets:14627 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:14410285 (14.4 MB) TX bytes:2192744 (2.1 MB) eth0 no wireless extensions. wlan0 IEEE 802.11bgn ESSID:"DIR-615" Mode:Managed Frequency:2.437 GHz Access Point: 00:90:4C:08:00:0D Bit Rate=150 Mb/s Tx-Power=20 dBm Retry short limit:7 RTS thr=2347 B Fragment thr:off Power Management:off Link Quality=70/70 Signal level=-22 dBm Rx invalid nwid:0 Rx invalid crypt:0 Rx invalid frag:0 Tx excessive retries:0 Invalid misc:186 Missed beacon:0 lo no wireless extensions. Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface 0.0.0.0 192.168.1.1 0.0.0.0 UG 400 0 0 wlan0 169.254.0.0 0.0.0.0 255.255.0.0 U 1000 0 0 wlan0 192.168.1.0 0.0.0.0 255.255.255.0 U 0 0 0 wlan0 PING google.com.Dlink (172.26.136.19) 56(84) bytes of data. 64 bytes from 19.136.26.172.in-addr.arpa (172.26.136.19): icmp_seq=1 ttl=249 time=102 ms --- google.com.Dlink ping statistics --- 1 packets transmitted, 1 received, 0% packet loss, time 0ms rtt min/avg/max/mdev = 102.547/102.547/102.547/0.000 ms |
Attached is a picture of the Quick Launch bar on my windows 10 setup. The top image (I added red arrows) shows three of the icons as kind of ‘blank page’ icon. This happens every time I reboot. If I click on one, the icon shows up (look at the second picture, I clicked on the left most ‘blank page’ icon – it is the command prompt). Anyone know how I can fix this so they show up after I boot? | I just did a fresh install of Windows 7 professional on my father's Toshiba Satellite laptop and everything went smoothly except for the fact that certain desktop shortcuts appear as a blank white page. I've tried: going in and changing the icon to many different things reloading the icon cache by deleting the IconCache.db file uninstalling his Free AVG as he heard the virus scanner might be preventing it (it wasn't and he put it back.) The one thing these icons have in common is that they are shortcuts to some very old DOS executables. One of them is Word Star 2000 to give you an idea. Does anybody have any other suggestions besides what we've tried? |
Preparing to move, I found this together with the papers I got when I bought my bike. But what is it? Is it important? It is about 2cm long. I have four of these... Maybe related to the disk brakes? I was hoping they could be pad spacers, but that might just be wishful thinking. | I boughtt a Shimano SM-MA-R160 Disc Brake Mount Adaptor for my bike. It came with these black plastic things in the lower right corner of the photo below. I have a bunch and don't know what are they used for: What are those plastic thingies called? What are they used for? How are they applied? How important are they? |
I'm running Ubuntu and want to execute a Java file from terminal by including multiple jar files. All my jars are included in tha jar folder. I tried javac -cp jar/A.jar: jar/B.jar: jar/C.jar: jar/D.jar MyFile.java I get below error. javac: invalid flag: jar/B.jar: Usage: javac <options> <source files> use -help for a list of possible option Can anyone guide how to use multiple jars in classpath ? | Is there a way to include all the jar files within a directory in the classpath? I'm trying java -classpath lib/*.jar:. my.package.Program and it is not able to find class files that are certainly in those jars. Do I need to add each jar file to the classpath separately? |
i have written a class i am trying get test coverage. i have written below. Could you please help me here Class : public class WrapperCam { public Boolean check{get;set;} public Campaign Cmp{get;set;} public WrapperCam(Id Idcc,String Nme) { this.check=false; this.Cmp = new Campaign(Id=Idcc,Name=Nme); } } Test class: @isTest Public class WrapperCamtest { @testSetup static void setupTestData(){ test.startTest(); Campaign campaign_Obj = new Campaign(id='00001',Name = 'suresh'); Insert campaign_Obj; test.stopTest(); } } Let me know what should i add here so that i get 100% coverage Thanks in advance! | This is a canonical question and answer developed by the community to help address common questions. If you've been directed here, or your question has been closed as a duplicate, please look through the resources here and use them to shape more specific questions. To browse all canonical questions and answers, including more unit test resources, navigate to the tag. This canonical question is intended to address several classes of common questions by providing a quick summary and links to comprehensive resources: How is code coverage obtained and calculated? How do I increase my coverage? Why can't I cover these lines? Why isn't the body of my loop or conditional statement covered? |
If an entity existed such as Laplace's demon, that could know with precision the current state of the universe and - using the laws of physics - could tell you your future with certainty, would you then be able to change it? | Possible Duplicate: As asked in the title, can a Universe which is deterministic at its fundamental level still allow free will? |
I never really understood how a terminal emulator (be it e.g. XTerm or the Linux virtual console) works. What transformations happen to the input (key up/down events) to produce the output (usually the standard input of the application that is running in the terminal, a signal being sent and so on)? What is actually the input for the terminal and what is already handled by the input drivers (in the kernel, X server, ...). How and where do the terminal capabilities databases like terminfo or termcap enter this process? How are "special" keys like arrows processed? And conversely: how does it work the other way round: application standard output/error → medium (screen, paper)? | Suppose I press the A key in a text editor and this inserts the character a in the document and displays it on the screen. I know the editor application isn't directly communicating with the hardware (there's a kernel and stuff in between), so what is going on inside my computer? |
here on meta has brought to my attention something I never realized before - non-employee moderators have access to some tools that can disclose an user EMail address. Since I was quite surprised by this discovery (yes, I know, it has probably been referenced before but I didn't know, sorry) I had the idea to look at the Privacy Policy to see what other data can non-employee access. I wasn't able to find any definitive info, only this relevant passage: We collect information such as your username, password, email address, IP address (collected at each site visit). This information is also used to identify individual users to the public Network and to award activities and attribute them to you. Your username and additional content you provide including your profile picture, question and answer content, and your reputation are visible publicly. Other limited information is visible to moderators, who have elevated access privileges, and may access content including your posts. For more information about moderators and their role in the Stack Overflow Network, please visit: /help/site-moderators. Sadly, this doesn't seem to further elaborate what other "limited information" is visible to moderators. I am therefore asking for support here: is there a page that list which users PII non-employee are granted access to? Or can anyone give me some info in that regard? | When editing my user profile (name, date of birth, etc.), how can I tell which information can be seen by other users (publicly visible) and what is only used by the system (and how it's used)? |
Let $P=K[x_1,\dots,x_n]$ be a polynomial ring over a field $K$ and $I = (f)$ be a principal ideal in $P$ generated by $f \in P - \{0 \}$. Moreover let $L \subset \{x_1, \dots, x_n \}$ and $\hat{P} = K\{x_i : x_i \notin L \}$. Show $I \cap \hat{P} = (0) \iff f \notin \hat{P}$. (Exercise 4, Section 3.4 from Kreuzer and Robbiano, Computational Commutative Algebra, vol. 1.) So I know that in one direction, if $f \not\in \hat{P}$, then $f$ contains a variable in $L$, but then $\hat{P}$ cannot contain any variable that is not in $L$. So the intersection must be $0$. (this need some justification...?) I am not sure about the other way. If someone could show me both, that would be good. | I have a polynomial ring $R = K[x_1,\dots,x_n]$ and $N \subset \{x_1,\dots,x_n\}$. Define $R_N = K[x_i:x_i\notin N]$. If $f\not= 0$, show $(f) \cap R_N = (0) \iff f \notin R_N$. So my entire argument hinges that $f \in R_{N^c}$ and clearly $f\in (f)$, but $f \not= 0$, so the intersection must be $(0)$ since $0 \in R_N$. I m not sure how to do the other direction. They look similar. |
I just updated from QGIS 1.7 to 2.0 on Mac. When I now open a project and create a map in the print composer the content of the map is lost when I open the project again later. The settings of the stored print are still ok, but the map content is not displayed. Instead it just says "Karte wird hier gedruckt" which means "map to be printed here" in English. Does anybody have an idea what the problem could be? It always worked fine with 1.7. | I am using QGis (latest version, OS X) and whan I create a map on map composer everything works fine. I export the map to pdf file and also goes fine. But when I save and close it and then close the main project and then open it again and then open the map composer that I saved, that map does not show anymore. However, I can still export the map but when it comes to editing I can't because everything is white. The commamd history appears empty. When opened on another computer (PC version) with a different version of QGis works fine. Here is the printscreen of my issue. |
use the equations $r=\sqrt{x^2 +y^2}$ and $\theta=\arctan(\frac{y}{x})$. I was able to get the partial derivative of of $r$ with respect to $x$ and $y$ and the partial derivative of $\theta$ with respect to $x$ and $y$. I have spent hours trying to figure this problem out by looking at the polar form of the Laplace equation as a reference but everything I try does not get me to that point. If anyone is up to the challenge please help me out! I apologize for not putting in Latex format, I have not quite gotten the hang of it yet. | I am stuck with an exercise that requires me to find the Laplacian $\Delta u=(D_x^2u+D_y^2u)$ of a 2d-function $u$ in polar coordinates (in the standard Euclidean plane). I found the following article on the net, and tried to follow its logic, but I could not understand two steps: at first, the representation of $D_x$ and $D_y$ in terms of $r, \theta$, at the bottom of page 2: $D_y=\sin\theta D_r+\frac{\cos\theta}{r}D_\theta$ and $D_x=\cos\theta D_r-\frac{\sin\theta}{r}D_\theta$ . When I draw a sketch of the plane with a circle and all the coordinates, I get that it should be $D_y=\sin\theta D_r+r\ \cos\theta D_\theta$, because the larger the radius is, the greater will be the impact of a change in $\theta$ on a change in $y$. What am I making wrong here? And then, secondly, what looks like an easy multiplication, namely taking the square of the above terms (on the top of page 3 in the link): $D_y^2=(\sin\theta D_r+\frac{\cos\theta}{r}D_\theta)(\sin\theta D_r+\frac{\cos\theta}{r}D_\theta)$ $=\sin^2\theta D_r^2+\frac{2\sin\theta \cos\theta}{r}D_\theta D_r+\frac{\sin^2\theta}{r^2}D_\theta^2 \\ -\frac{\cos\theta}{r^2}D_\theta + \frac{\cos^2\theta}{r}D_r - \frac{\cos\theta \sin\theta}{r^2}D_\theta$ and similarly for $D_x$. I don't see from where the last three summands come, what I see is: $(a+b)(a+b)=a^2+2ab+b^2+c+d+e$ and I cannot see the context of $c,d,e.$ It would be great if you could explain those issues to me! |
I want to merge rows into single column using FOR XML PATH in SQL. Here is my Query: select d.Device from tbl_Sales_OrderItems tsoi left join tbl_devices d on d.DeviceID=tsoi.DeviceID where salesorderid=102 and tsoi.Quantity>0 and tsoi.TypeID=1 union all select d.Partnumber Device from tbl_Sales_OrderItems tsoi left join tbl_VendorParts d on d.VendorPartID=tsoi.RefID where salesorderid=102 and tsoi.Quantity>0 and tsoi.TypeID=2 Here i am getting two rows i.e Two Device name in from tbl_Sales_Order. Now these rows i want to get in single row using FOR XML PATH into a single column. Further after applying FOR XML PATH i want to use it in select query i want to use the row value which would be as follows. Select salesorderid,@resultinRow from tbl_Sales_Orders Output Required: SalesOrderID Devices 102 Device1,Device2 103 Device3,Device2 | I'm trying to migrate a MySQL-based app over to Microsoft SQL Server 2005 (not by choice, but that's life). In the original app, we used almost entirely ANSI-SQL compliant statements, with one significant exception -- we used MySQL's group_concat function fairly frequently. group_concat, by the way, does this: given a table of, say, employee names and projects... SELECT empName, projID FROM project_members; returns: ANDY | A100 ANDY | B391 ANDY | X010 TOM | A100 TOM | A510 ... and here's what you get with group_concat: SELECT empName, group_concat(projID SEPARATOR ' / ') FROM project_members GROUP BY empName; returns: ANDY | A100 / B391 / X010 TOM | A100 / A510 So what I'd like to know is: Is it possible to write, say, a user-defined function in SQL Server which emulates the functionality of group_concat? I have almost no experience using UDFs, stored procedures, or anything like that, just straight-up SQL, so please err on the side of too much explanation :) |
I think a good approach to allow have discussions on SO and SU would be have a "discussion" checkbox, like we have the "community wiki" one. Discussions could appear separated from Questions, and would not have the "accept answer" button. That would be really good! | Take , and note the description: Proposed Q&A site for professional and expert amateur chefs interested in the more subjective aspects of cooking; this would be to Cooking SE as Programmers SE is to Stack Overflow It seems like is MASSIVELY popular (has more views per-day than any other proposal by a factor of almost 2). There's also a . Should we allow this trend to continue, possible resulting in things like a subjective web applications proposal? It seems like almost ANY proposal's users could benefit from having a place to ask subjective questions, seeing how much the subjective programmers proposal took off, how many good questions are asked and closed as subjective, and how many successful blogs and discussion sites there are. But it seems like having totally different sites for this is wrong, as they would share no more official connection between them than with a gaming and skateboarding proposal. If they could be linked somehow, at the least like Stack Overflow and Server Fault are linked as part of a trilogy, they could both be more prosperous. Another idea would be having a subjective version of every site (subjective.blah.com, like every site has a meta.blah.com). This would be a great way to link the two, and the separation would still be there as it. Heck we could even do it with the existing trilogy sites, with a 'belongs on subjective' auto-move feature like 'belongs on meta'. It's obvious that people want to ask subjective questions. The issue at hand is how (or if) we choose to enable them to do that with the Stack Exchange model. This is a much more long term issue that will need heavy discussion before any consensus can be reached. EDIT: I see this question proposed something like this for polls. What I am proposing is a separate dominion for all questions that are valid except for being subjective. Hence every site could have a normal section, a subjective section, and a chat section. This may seem complicated, but IMHO it's a great way to divide up a topic. There would be a place to answer questions, discuss topics, and just talk. As far as I can see this covers every area users would be concerned with, leading to a one-stop site that would provide good organization for all areas of a topic. Thoughts? (sorry for the big wall of text ;) |
I have configured a server with Gentoo 64 bits that it has IPv4 and IPv6 and they are working well. But I don't know how specify the IPv6 of the server in /etc/hosts file. With or without "/64" final?: ... ipv4.XXX.XXX.XXX nsXXXXXXX.ip-XXX-XXX-XXX.eu ipv6:XXxX:XX:xxxX::/64 nsXXXXXXX.ip-XXX-XXX-XXX.eu .... or .... ipv4.XXX.XXX.XXX nsXXXXXXX.ip-XXX-XXX-XXX.eu ipv6:XXxX:XX:xxxX:: nsXXXXXXX.ip-XXX-XXX-XXX.eu .... ? | Pasted below this question is a sample of a /etc/hosts file from a Linux (CentOS) and a Windows machine. The Linux file has two tabbed entries after the IP address (that is localhost.localdomain localhost) and Windows has only one. If I want to edit the hosts file in Windows to have the machine name (etest) instead of localhost, I simply replace the word localhost with the machine name I want. The machine need not be part of a domain. In a Linux machine, the two entries localhost.localdomain and localhost seems to indicate that I will need the machine to be part of a domain. Is this true? Can I simply edit both entries to etest so that it will read: 127.0.0.1 etest etest or is it required that I substitute one entry with a domain name? Additionally, please let me know what the second line of the /etc/hosts file on the Linux machine is for. ::1 localhost6.localdomain6 localhost6 hosts file on a Linux machine: # Do not remove the following line, or various programs # that require network functionality will fail. 127.0.0.1 localhost.localdomain localhost ::1 localhost6.localdomain6 localhost6 hosts file on a windows machine: # Copyright (c) 1993-1999 Microsoft Corp. # # This is a sample HOSTS file used by Microsoft TCP/IP for Windows. # # This file contains the mappings of IP addresses to host names. Each # entry should be kept on an individual line. The IP address should # be placed in the first column followed by the corresponding host name. # The IP address and the host name should be separated by at least one # space. # # Additionally, comments (such as these) may be inserted on individual # lines or following the machine name denoted by a '#' symbol. # # For example: # # 102.54.94.97 rhino.acme.com # source server # 38.25.63.10 x.acme.com # x client host 127.0.0.1 localhost |
I am moving overseas for a few months and will be working remotely, which will require me to take my desktop computer. What are the best methods to take a desktop computer overseas? What potential issues are involved? Should I stuff the entire desktop into a hard-case samsonite luggage (and bubble-wrap/cushion it)? Should I remove sensitive parts and take those sensitive parts separately? Will the TSA say anything if I remove the GPU and CPU and take that with me as carry-on luggage? Also, I hear that the TSA may open your checked-in luggage, and for desktops that they may remove the heatsink on the CPU. I do not want my CPU to get damaged, so in that case should I remove the heatsink, and CPU so that no one else has to do it? Anything else to consider? | I am moving from Malaysia to the US, and planning to bring my desktop computer with me. I plan to pack it in my checked-in luggage. Will the computer risk being damaged? Any precaution should I take to reduce this risk? Will there be any trouble with the airline or immigration about bringing computer? |
I have an exe file which is written in .net language . I have no source code for same but I want to change some functionality in this so convert it to visual studio source code. is there any way to do this? | I wrote a C# application for a client a couple of years ago, but I no longer have the source code. All I have is the EXE that I deployed on the client's PC. Is there a way I can generate C# source code from the EXE? |
I am working on a computer that does not have a DVD drive, and can read but not boot from USB. However, it does have internet access. Is there any super minimalist version of Ubuntu 13.10 that can be burned to a CD instead of a DVD, and then fetch anything still missing from the internet at runtime? | How do I burn the latest 12.10 790 MB ISO to a CD? My burning software says insert a disk but 700 MB CD's are too small. I tried a DVD and that didn't work either. |
I understand how both graphs are drawn, but I do not understand why you cannot just convert one into another. It feels natural to me to just convert $2\log x$ to $\log x^2$ and not have to worry about the domain restriction. | These two are supposed to be equivalent because of the properties of logarithms, but the domains of $\ln(x^2)$ and $2\ln x$ seem different to me. For example, if I substitute $x=-1$ into the first, I get 0. But in the second, I get a non-real answer. Why is this? The domains of these functions, when graphed, seem different as well. But everything I've been taught so far, and most of the things I can find on the web, do not explain this inconsistency. Typically, I consider the property $\ln(a^b) = b \ln a$ to be true... I am only a senior in high school, currently in Calculus I, but hopefully the explanation won't be too outside of the realm of my understanding. But even if it is, I would still like to know the answer. Thanks in advance |
I have apache2 working and can run php files by navigating to localhost using chrome browser. However I'd like to be able to launch the files within the browser from the command line. google-chrome myfile.html works but google-chrome myfile.php doesn't, even though I'm launching it from my apache root. Any help much appreciated. | As the title says: google-chrome index.phpdownloads the file immediately instead of opening it. Is there a way to change this? |
Consider the proof of: $$\zeta(2) = \frac{\pi^{2}}{6}$$ So the proof assume that (because of Euler decomposition) $$\frac{\sin(x)}{x} = \prod_{n > 0}\left(1 - \frac{x^{2}}{(n\pi)^{2}}\right)$$ Why should we consider the $\frac{\sin(x)}{x}$, that $\sin(x)$ has the same decomposition? Please tell me where's my fault. | As I have heard people did not trust Euler when he first discovered the formula (solution of the ) $$\zeta(2)=\sum_{k=1}^\infty \frac{1}{k^2}=\frac{\pi^2}{6}.$$ However, Euler was Euler and he gave other proofs. I believe many of you know some nice proofs of this, can you please share it with us? |
I have string logo.cr.Button and function logo.cr.Button = function(){ //something } var strg = 'logo.cr.Button'; strg(); now somehow i have to make that string a function call like strg(); but it is saying strg is not a constructor here | I have the name of a function in JavaScript as a string. How do I convert that into a function pointer so I can call it later? Depending on the circumstances, I may need to pass various arguments into the method too. Some of the functions may take the form of namespace.namespace.function(args[...]). |
I have been struggling with my internet provider for a month now. Our bandwidth is too low for the price we are paying for our internet contract. Is there any method/tool/program to monitor my internet bandwidth (download speed) constantly for like a day or at least for 6-8 hours? I would like to make an excel or pdf from the result log so I can show them to proof that they service is too low. The one-time measurements not good enough because sadly all the time when I contact their support our connection works well. Thanks in advance. | Right now I'm in the process of possibly switching from a Cable provider to a DSL provider. I have both connections live, and before I cancel one or the other, I'm wanting to do some exhaustive testing of the internet connection. I have three major questions: What are some approaches that I can quantitatively test the speeds (both up and down) and quality of my internet connections (ping, time connection is down, etc,.)? Are there other consideration that should be taken when testing an internet connection? Are there any tools that can do this automatically and capture results? Note: if you decide to suggest a piece of software, please in doing so. Also I'm looking to be able to save any data from the software for detailed analysis and comparison Overall, I'm looking to compare the two connections over multiple periods of time such as peak hours (1600 - 2100 in my area), and with different loads such as streaming movies, uploading files, etc,. This question was Featured in the blog! Read the for more details or yourself |
I recently installed Ubuntu and in the process of completion i realized that i had not dedicated a swap memory during installation. How can i go about adding the swap memory without reinstalling Ubuntu. | I did not create a swap partition during Ubuntu installation. Later, I freed up some space and made a swap partition. Now after each boot up, I am manually opening gparted to right-click the swap partition to turn on the 'swapon' option. How can I automatically enable the swap partition at boot? Also, if I had not created the swap partition, what are my other options? |
I am programming with normal pointers, but I have heard about libraries like Boost that implement smart pointers. I have also seen that in Ogre3D rendering engine there is a deep use of shared pointers. What exactly is the difference between the three, and should I stick on using just a type of them? | What is a smart pointer and when should I use one? |
I have an HD 7870 and I read it is the exact same card with the R9 270X, just with another name. I want to upgrade from 14.04, but the AMDGPU PRO does not support the 7870. However, it supports the R9 290X. Will it work? | The new open source AMDGPU driver pre-installed in Ubuntu 16.04 should support all the "Volcanic Islands" cards out-of-the-box. This means that AMD Radeon R9 285, R9 380/380X and R9 Fury/FuryX graphics cards will be supported out-of-the-box if Ubuntu 16.04 LTS is installed. However I read that the open source AMDGPU driver has an experimental support for the "Sea Islands" graphics cards (HD7790, R7 260, R9 290, R7 360, R9 390). Is this support enabled by default on Ubuntu 16.04, or will these graphics cards use the Radeon driver? Thanks |
Can I run XCOM 2 in my 32-bit Windows 7 machine? The recommendation says it needs 64 bit to run the game. | Is there a service that I can use to check if my machine will be able to run a certain game? |
Trying to do the upgrade of kubuntu from 19.04 to 19.10 Non-LTS versions are allowed (Prompt=normal in /etc/update-manager/release-upgrades) update-manager says my system is up to date. Running do-release-upgrade produces "No new release found" do-release-upgrade -d shows: "Upgrades to the development release are only available from the latest supported release." Any ideas why I can't upgrade? Thanks, Rudolf | Recently I have installed an older version of Ubuntu on my old machine. Whenever I try to install any software, I get an error saying it couldn't be found: $ sudo apt-get install vlc Reading package lists... Done Building dependency tree Reading state information... Done E: Couldn't find package vlc |
Can we capitalize the first letters of words in a string to Uppercase and return the string without using slice(1) in javascript? If possible please help me find this out? function titleCase(str) { str=str.toLowerCase().split(" "); for(var i=0;i<str.length;i++){ str[i] = str[i].charAt(0).toUpperCase()+str[i].slice(1); } str=str.join(" "); return str; } titleCase("sHoRt AnD sToUt"); | 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. |
Sometimes, while trying to edit a file, the editor says "cannot write to file because is taken by another process". So, is there a tool which takes an input a file name (with its path) and tells which process has taken it with write-only acces? If not, what is the thecnical reason that cannot be answered? I ask this because is so annoying that the message does not inform what is the damn process locking the file and cannot understand why the OS programmer didn't give that obvious vital information. Thanks! | How can I find out which process is locking a file or folder in Windows? For instance, when trying to delete a folder, Windows reports this: The action can't be completed because the folder is open in another program Happens the same with a file, but how do I find out what program or application is currently using it and preventing me from deleting the file or folder? |
I'm working on a Partial copy sandbox with a standard System Administrator profile User. Why can I only create Hierarchy Custom settings? In production I can create list Type custom Settings with the same User. I couldn't find any related info in either the Custom Settings limits : or Defining custom settings help : | I am trying to create a new custom setting in salesforce but the Setting Type field is greyed out and fixed to Hierarchy. What could be the possible problem? |
I've been developing for a CraftBukkit Minecraft server. This gives me a good API to work with. This API includes the onCommand method, which allows me to implement new commands. I've just been trying to do that, but when I send a command such as /example arg0, for some reason I can't compare with arg0 from my code. I'm trying to check for when args[0] == "on", yet although args and args[0] are both defined and I set args[0] to "on", the comparison still returns false. private CBPlugin pluginReference; public NerfTntExecutor(CBPlugin plugin) { // (...) pluginReference = plugin; } public boolean onCommand(CommandSender sender, Command cmd, String label, String[] args) { if (sender.hasPermission("command.op.nerftnt")) { if(args.length > 0) { // (...) sender.sendMessage(args[0]); sender.sendMessage(args[0].getClass().getName()); if(args[0] == "on") sender.sendMessage("true"); return true; } else { sender.sendMessage("Not enough arguments!"); return false; } } else { pluginReference.getLogger().info("No permission"); return false; } } The sender.sendMessage calls display the data given back to the person who sent the command. In this case, args[0] is displayed as "on" and args[0].getClass().getName() gets shown as java.lang.String - the type of the argument. However, the next line if(args[0] == "on") is false. Why is this? I seem to be comparing a String to another String, and they both have the same contents. Why should a comparison of the two return false? | I've been using the == operator in my program to compare all my strings so far. However, I ran into a bug, changed one of them into .equals() instead, and it fixed the bug. Is == bad? When should it and should it not be used? What's the difference? |
I have always read that light is reflected by a mirror. My question is how does reflection take place on a microscopic level? A mirror is composed of atoms and electrons revolving around the nucleus. So where does the photon strike and go? | This well-observed phenomenon has, besides several others, always been a fascination to me. We are well aware of several theories, experiments, and practical applications of this well-known phenomenon, but is it established what goes on at the grassroots of reflection? My high school teacher once told me that whenever light is incident on any reflecting surface, its electrons absorb the energy of the photon and release back the same energy. If this is actually true, then I have plenty of questions to continue, but if it is not, then what is reflection, and how and why does it take place? |
I am new to Blender and I want to make this metal look more realistic. I am using a PBR method but the handle on this sword looks like it is missing something. Any tips would be appreciated. Let me know if you would like the .blender file or a screenshot of the nodes. | I'm trying to make a gun for an alien space ship and I need to know how to create a dark gray metal look. I have tried mixing a Diffuse and Glossy BSDF, but it isn't quite what I am looking for. I need some light falloff to help get that "extra touch", but I don't know how to do that. |
Recently I downloaded a program on windows, and I think it installed a key-logger. I quickly went to Ubuntu, and deleted the program files from there. I am quite sure that it is gone, but I must have deleted some file that is associated to the windows login (Which I don't know how, since I only deleted the the program's folder from the PrgramFilesx86 directory),because now when I login to windows, it says "loging in" then it flashes grey, then logs out. I looked up answers to this question, and it seemed like you needed to edit the windows registry. I was wondering if anyone could tell me how to do this from ubuntu. I saw a post that said you needed to install , but their instructions on how to edit the actual registry did not work. I was wondering if anyone could help me fix my problem. | My laptop is a Windows 7 / Ubuntu 12.04 LTS dual-boot setup. I've been experimenting with alternative desktop shells on my Windows partition, such as KDE and . After setting Cairo as my default shell, I decided to restart my computer and log back into Windows just to make sure everything was working properly. However, after logging in, I found myself left with nothing but the mouse cursor and a blank desktop filled with the default background color. I know the registry setting I need to change in order to restore Windows Explorer as the default shell from my prior experimentation with KDE, but I obviously can't use regedit if I can't load into a working desktop. However, I can still use my Ubuntu partition with no problems. This has me wondering if there is a way I can mount my Windows partition in Ubuntu and somehow edit the registry from there. How would I go about doing this, and do I need any extra packages for it? |
One time when Mark Watney entered the airlock the plastic-like wall broke. It looked like air started coming in even though the pressure outside should never be higher than the one inside. At the end the whole airlock exploded. I'm having hard time imagining why this happened. How is this explained scientifically? | In The Martian, the "Hab" explodes at some point in the film, specifically the time that the airlock blows out. Is it explained what exactly happens that causes this? I watched the film in the U.S. and English isn't my first language, so some details may have been lost for me. |
I need to make the child height relative to the viewport. Using HTML: <div class="parent">My divider <div class="child"> Inside the div </div> </div> and CSS: .t1 { background:#f00; color:#fff; } .t2 { background:#212121; height:100vh; } As you can see from the example, There's always this small gap, because it takes into account the overall height of the parent. However, I only need the child to fill "the rest" of the viewport from parent. How should I proceed? I've tried many other things, but without sufficient result | I am working on a web application where I want the content to fill the height of the entire screen. The page has a header, which contains a logo, and account information. This could be an arbitrary height. I want the content div to fill the rest of the page to the bottom. I have a header div and a content div. At the moment I am using a table for the layout like so: CSS and HTML #page { height: 100%; width: 100% } #tdcontent { height: 100%; } #content { overflow: auto; /* or overflow: hidden; */ } <table id="page"> <tr> <td id="tdheader"> <div id="header">...</div> </td> </tr> <tr> <td id="tdcontent"> <div id="content">...</div> </td> </tr> </table> The entire height of the page is filled, and no scrolling is required. For anything inside the content div, setting top: 0; will put it right underneath the header. Sometimes the content will be a real table, with its height set to 100%. Putting header inside content will not allow this to work. Is there a way to achieve the same effect without using the table? Update: Elements inside the content div will have heights set to percentages as well. So something at 100% inside the div will fill it to the bottom. As will two elements at 50%. Update 2: For instance, if the header takes up 20% of the screen's height, a table specified at 50% inside #content would take up 40% of the screen space. So far, wrapping the entire thing in a table is the only thing that works. |
What is the correct sentence. I am a IT degree holder. I am an IT degree holder. | 99% of the time, I'm clear on when I should use "a" versus "an." There's one case, though, where people & references I respect disagree. Which of the following would you precede with "a" or "an," and why? FAQ FUBAR SCUBA [Note: I've read the questions and , but the rules given there don't necessarily apply here.] [Edited to add] Here's a shorter (and hopefully clearer) version of the question… In written English, which is correct (and why): "a FAQ" or "an FAQ"? Some references with differing opinions: an: the and a: the Microsoft Manual of Style for Tech Publications, 3e either: the and |
In the online visit visa application for the UK, I have to add immediate family members. My sister's family lives there. Do I have to add her husband too as an immediate family member? | I am about to apply for a UK Standard Visitor visa on an Indian passport. I have sufficient funds as shown by bank statements and am a full-time employed permanent resident of Canada. The application requires me to state whether I have friends/family and then requires all their details (their status in UK, address etc). I have a few old friends and one cousin but do not want to add them because of the details required. Do you think it is a plus point or can go against me if I say "NO" to Do you have friends or family in UK? |
I've tried everything to fix this. Restarting my computer, closing Blender and opening it again, uninstalling Blender and installing it again. Unless it's a bug, I don't know how to fix this. Advice anyone? Also here's a screenshot of the issue I'm having.: I made the mountain after selecting "Spherical Falloff", I'm trying to make a hill, and it's obvious that is no hill. | I am a beginner and I think this is a basic, I am trying to use the blender to create a basic Low Poly Illustrations mountains. So according to tutorials but all I could do with the tutorial's help is this Need help. What should i change to make it the one in the tutorials. thanks in advance. |
Sometimes I don't know which Stack Exchange website is suitable for my question. For example, in the past, I had a question about anonymousness of VPN. I asked this question on Network Engineering. But guys told me that is an off-topic question. Finally I found it is suitable for Information Security and got a good answer there. So I'm wondering if Stack Exchange could add a function to provide suggestion about suitable website based on some information. I guess the easiest one is tag. If I add "networking" and "anonymous" tags, it could suggest me to ask this question on Information Security. | Take for example both at SO and SU. Now that there's , (new) users asking a LaTeX question should at least be informed that there is a new Stack Exchange site dedicated to TeX and thus increases their chance of an answer. This should happen before the question is actually posted and ideally offer the option to post the question directly there instead (without the need to copy-paste). LaTeX is just an example, there's also , , etc., and it is obvious that this can only be decided on a case-by-case basis which is why I certainly do not suggest migrating questions automatically when these tags are used. But informing users of that possibility would probably help the SE network in general. |
The tomb had been robbed of its treasures. (Oxford Dictionary) What should I think that this 'of' means? I know 'of' has the similar meanings to 'from' and 'about' but I am not sure which it is in this case. Thanks and a happy new year to you! »» I needed to know the meaning of 'of' in this usage and I've seen that question and answer but that one was about 'rob' and not explained about what I needed to know. »» I want to comment on the 3rd answer because I like it and want to say something. I'm trying to put it in words now.. please give me some time. | From : Remember the child, in some ways, identifies with both of those parents so if the mother is really asking the child to be her sounding board, she robs that child from the ability to feel good about his connection with the father. What's the meaning of robs that child from the ability to feel good about his connection with the father? I know that rob has two usages: rob something from somebody. rob somebody of something. But it seems that *the ability to feel good about his connection with the father is belonging to "something", so is it more appropriate to modify the word "from" to "of"? just as follows: robs that child of the ability to feel good about his connection with the father Which usage is correct? Thanks. |
Show that if $f$ is a non-constant entire function,it cannot satisfy the condition: $$f(z)=f(z+1)=f(z+i)$$ My line of argument so far is based on Liouville's theorem that states that every bounded entire function must be a constant. So I try-to no avail-to show that if $f$ satisfies the given condition, it must be bounded. I haven't made much progress with this, so any hints or solutions are welcome. | Let $f: \Bbb C \to \Bbb C$ be an entire (analytic on the whole plane) function such that exists $\omega_1,\omega_2 \in \mathbb{S}^1$, linearly independent over $\Bbb R$ such that: $$f(z+\omega_1)=f(z)=f(z+\omega_2), \quad \forall\,z\in \Bbb C.$$Prove that $f$ is constant. The intuition seems clear to me, we have the three vertices of a triangle given by $0$, $\omega_1$ and $\omega_2$. All points in the plane are one of the vertices of that triangle under a suitable parallel translation. The constant value will be $f(0)$, fine. Throwing values for $z$ there, I have found that $$f(n\omega_1) = f(\omega_1) = f(0)=f(\omega_2) = f(n\omega_2), \quad \forall\, n \in \Bbb Z.$$ I don't know how to improve the above for, say, rationals (at least). Some another ideas would be: Checking that $f' \equiv 0$. I don't have a clue of how to do that. Write $w = a\omega_1+b\omega_2$, with $a,b \in \Bbb R$, do stuff and conclude that $f(w) = f(0)$. This approach doesn't seem good, because I only have a weak result with integers above. Finding that $f$ coincides with $f(0)$ on a set with an accumulation point. This seems also bad: the set on with $f$ coincides with $f(0)$ by which I found above is discrete. Nothing works and this is getting annoying... And I don't see how analyticity comes in there. I'll be very thankful if someone can give me an idea. (On a side note.. I know that this title is not informative at all. Feel free to edit if you come up with something better.) |
I live in South Africa and would like to visit France and Italy. I was hoping to enter in Paris and fly back home from Rome. It it possible to exit the Europe from a different country of entry? | I am visiting a friend in Switzerland for ten days. I have already got visitor's visa for the same on my Indian passport. Particulars mentioned on my visa are: 1. 'Etats Schengen' , 2. Single entry 3. Dates of visit. & 4. Type of visa : C. I understand that having already got ‘Etats Schengen' visa, I can travel to all Schengen countries. I am also planning to visit Paris for a day during my stay in Switzerland. However, I never mentioned this in my visa application. I am planning to take a train from Geneva to Paris and book a hotel in Paris for one night. Can I possibly plan my Paris trip this way as I have Schengen visa, or I am not allowed to travel out of Switzerland as I never mentioned this in my visa application? Also what does Single entry on my Schengen visa means: does it mean that I can enter and leave Switzerland only once or it means that I can enter and leave the Schengen region only once. |
When I print out the coding for //display the board public static void main(String[] args) { Scanner keyboard = new Scanner(System.in); Scanner scanner = new Scanner(System.in); char [][] gameboardTwo = {{'*', '*', 'S', 'T', 'A','R', '*', 'W', 'A', 'R', 'S', '*', '*', '*'}, {'*', '*', 'E','P', 'I', 'S', 'O', 'D', 'E', '*', '*', 'I', 'V', '*'}, {'*', '*', '*','*', '*', '*', '*', '*', '*', '*', '*', '*', '*', '*'}, {'*', '*', '*','*', '*', '*', '*', '*', '*', '*', '*', '*', '*', '*'}}; System.out.print(gameboardTwo); } } all I get in return is this: [[C@75b84c92 Process completed. | In Java, arrays don't override toString(), so if you try to print one directly, you get the className + '@' + the hex of the of the array, as defined by Object.toString(): int[] intArray = new int[] {1, 2, 3, 4, 5}; System.out.println(intArray); // prints something like '[I@3343c8b3' But usually, we'd actually want something more like [1, 2, 3, 4, 5]. What's the simplest way of doing that? Here are some example inputs and outputs: // Array of primitives: int[] intArray = new int[] {1, 2, 3, 4, 5}; //output: [1, 2, 3, 4, 5] // Array of object references: String[] strArray = new String[] {"John", "Mary", "Bob"}; //output: [John, Mary, Bob] |
lets say i make a request to so my picture.jpg is supposed to be in htdocs/files/picture.jpg how do i configure if picture.jpg does not exist in htdocs/files then look it up inside htdocs/files/alt? the filename varies, but the alternate directory name (alt) is fixed (which reside inside the original directory) is this achievable using apache config? | This is a about Apache's mod_rewrite. Changing a request URL or redirecting users to a different URL than the one they originally requested is done using mod_rewrite. This includes such things as: Changing HTTP to HTTPS (or the other way around) Changing a request to a page which no longer exist to a new replacement. Modifying a URL format (such as ?id=3433 to /id/3433 ) Presenting a different page based on the browser, based on the referrer, based on anything possible under the moon and sun. Anything you want to mess around with URL Everything You Ever Wanted to Know about Mod_Rewrite Rules but Were Afraid to Ask! How can I become an expert at writing mod_rewrite rules? What is the fundamental format and structure of mod_rewrite rules? What form/flavor of regular expressions do I need to have a solid grasp of? What are the most common mistakes/pitfalls when writing rewrite rules? What is a good method for testing and verifying mod_rewrite rules? Are there SEO or performance implications of mod_rewrite rules I should be aware of? Are there common situations where mod_rewrite might seem like the right tool for the job but isn't? What are some common examples? A place to test your rules The web site is a great place to play around with your rules and test them. It even shows the debug output so you can see what matched and what did not. |
If you end a question with a proper noun that requires quotation marks, i.e. a play's name, do you still put the question mark (?) inside the quotation marks? EXAMPLE: Did you see "South Pacific"? -or- Did you see "South Pacific?" | Possible Duplicate: If I'm quoting something someone said and the quote does not have a question mark, but I want to end the sentence with a question mark, would it be Are you sure she said "Spicy?" or Are you sure she said "Spicy"? |
By Induction $$\sum_{i=0}^n i^2 = \frac{(n^2+n)(2n+1)}{6}$$ But I didn't understand how I can do this, for this function or another function, i.e how to derive the right hand side function for the summation. | I am just starting into calculus and I have a question about the following statement I encountered while learning about definite integrals: $$\sum_{k=1}^n k^2 = \frac{n(n+1)(2n+1)}{6}$$ I really have no idea why this statement is true. Can someone please explain why this is true and if possible show how to arrive at one given the other? |
How can I open the terminal app in Ubuntu desktop booted from live cd(not intalled in hard drive) ? | What is a terminal? How do I open a terminal window? How do I use the terminal? |
In KDE I could set windows from some applications to be 'Always on Visible Workspace' permanently after restarts. How do I do this to some applications like Slack in latest Ubuntu 18.04 with GNOME shell? | I use pidgin as my chat client on ubuntu lucid. Whenever I have a chat window open, I like to mark it as "Always on visible workspace" as it's just more convenient. Is there a way that I can force chat windows to already be marked as that when they open up? So, if someone started a conversation with me on gtalk (for instance) the window would automatically be on all workspaces, and I wouldn't have to mark it manually. |
I know that "which" or "that" should be used to refer to entities, and "who" to people. However, I have come across "who" being used to refer to companies and agencies in a UK ESL textbook for the second time. So is the following sentence grammatical in UK English? An agency or a company who will help you ... | I have some doubts about the usages of That and Who. Sometimes I read sentences such as. "You are someone I love" "You are someone WHO I love" Or "People were asked to describe the qualities they look for in a friend" "People were asked to describe the qualities THAT they look for in a friend" Why in some of these sentences WHO or THAT are omitted and others are not. Could somebody help me with this? I'll appreciate it! Thanks a million. |
on my question, user Javi_gg1 send me an answer that's right for me. This answer have this code \draw[ultra thick, red] plot (\x, {sin(deg(exp(ln(\fmin)+\x/\xmax*(ln(\fmax)-ln(\fmin)))*\x))} ); I could not understand how he works. is there anyone (maybe javi_gg1) who can explain it to me? Because I would change some aspect. | \documentclass{standalone} \usepackage{tikz} \usepackage{pgfplots} \pgfplotsset{compat=1.15} \begin{document} \newcommand{\xmax}{14} \newcommand{\fmin}{(pi/3)} \newcommand{\fmax}{(2*pi)} \begin{tikzpicture}[domain=0:\xmax, samples=500] \draw[ultra thick, red] plot (\x, {sin(deg(exp(ln(\fmin)+\x/\xmax*(ln(\fmax)-ln(\fmin)))*\x))} ); \end{tikzpicture} \end{document} I would understand if LaTeX repeat the code below this statement many times. |
Let’s call a group $G$ invertible, if $\forall H \triangleleft G$, there $\exists K \triangleleft G$, such, that $K \cong \frac{G}{H}$ and $H \cong \frac{G}{K}$ All finite abelian groups are known to be invertible. All simple groups also are invertible. However the vast majority of finite groups seems to be non-invertible: that includes symmetric groups, dihedral groups, holomorphs of cyclic groups, generalised quaternion groups and so on… So my question is: Is there some sort of classification of invertible finite groups? | A common mistake for beginning group theory students is the belief that a quotient of a group $G$ is necessarily isomorphic to a subgroup of $G$. Is there a characterization of the groups in which this property holds? If this question is too broad, I might ask if such a characterization exists for $p$-groups. History: I originally posed the opposite question, regarding groups for which $\exists N\unlhd G\,:\, \not\exists H \unlhd G\, \text{ s.t. } H \cong G/N$, and crossposted this to . I received an answer there to the (now omitted) peripheral question about probability, which shows that most finite groups probably have this property. After this, I changed the question to its current state, as this smaller collection of groups is more likely to be characterizable. |
The question is to prove the inequality $e^x\le e^{x^2} + x$. I tried the Taylor expansion like ${e^x} = 1 + x + \frac{{{x^2}}}{{2!}} + \frac{{{x^3}}}{{3!}} + ...$ and $x + {e^{{x^2}}} = 1 + x + \frac{{{x^4}}}{{2!}} + \frac{{{x^6}}}{{3!}} + ...$ but cannot see anything useful out of this. Anyone can provide some help? Thank you. | Does anybody have a simple proof this inequality $$e^x\le x+e^{x^2}.$$ Thanks. |
Does Ubuntu 18.04 Server Raspberry Pi support hidden wireless? I try to figure out this issue for a few days. could you give me advance. thanks 1)/etc/netplan/50-cloud-init.yam <- I don't have any idea to set hidden wifi. network: version: 2 renderer: networkd wifis: wlan0: dhcp4: no dhcp6: no addresses: [192.168.1.31/24] gateway4: 192.168.1.254 nameservers: addresses: [8.8.8.8] access-points: myssid: {password: mypasswork} ###no any idea for hidden wifi### 2)/etc/network/interfaces <- not working allow-hotplug wlan0 iface wlan0 inet static address 192.168.1.31 netmask 255.255.255.0 gateway 192.168.1.254 wpa-conf /etc/wpa_supplicant/wpa_supplicant.conf network={ ssid="myssid" scan_ssid=1 psk="mypassword" } | I've a problem with Netplan not connecting to WiFi network with hidden SSID. It works great if I'll make this network visible. But no chance with hidden one. Any options to configure that? |
Ubuntu 14.04 Trusty Tahr, Gnome. How do I add application icons on the top panel? This is what I had on Precise: And this is what I have on Trusty: I tried icon dragging and the right click, but they only launch the application. EDIT: note that this question is about Ubuntu 14.04 Trusty Tahr, the thing that worked in previous releases (such as Precise) does not work anymore. | Because of Unity's inability to use any Gnome panel applets, I changed back to the classic gnome panel. However, even in the classic interface, I'm finding I can't right-click the Gnome panel to change anything. How do you add applets to the Gnome panel in the classic interface? |
I am looking to buy a nexus 4. I know that the new nexus 5 is coming out, and it is being released with Android KitKat installed. If I get a nexus 4 from a store such as best buy or another one, will my Nexus 4 come with Kitkat? If not, When is KitKat expected to be realised for the Nexus 4. If I am not in a rush to get a new phone, would it be better to by the Nexus 4 now, or the Nexus 5 in a few months? | Android 4.4 (KitKat) was officially announced on October 31, 2013. (You can review at the official Android Developer's site or the .) Of course, not all devices will get this update right away and others won't get it at all. Each manufacturer and carrier often choose to add their custom modifications which tend to delay the official release. When will each device get Android 4.4, either officially or unofficially, if ever? See also: |
I have text file DollarToPound.txt with some Dollar signs ($) please provide a shell script to replace dollar symbol with Pound(£) with sed command. iam getting command garbled error!!! please help. Operating system used-- solaris 10 | I have file test_output_archive.svd with some Dollar signs ($). I have generated a shell script Replace_dollar_pound.sh with cat command to replace dollar symbol with Pound (£) script is working on Solaris 10, Dollar getting replaced as expected. In Solaris 11, but the dollar is not getting replaced, not throwing any errors Content of test_output_archive.svd : Line Rental $9 OOB Only for $10 Replace Dollar symbol with Pound at step1, Remove junk charactes at step 2, Remove temp file at step3, Rename at step4** Content of Replace_dollar_pound.sh : cat test_output_archive.svd | tr "\044" "\243" > temp_archive.svd cat temp_archive.svd | tr -d "\302" > test_output_archive2.svd rm temp_archive.svd mv test_output_archive2.svd test_output_archive.svd Any Modifications to be done as OS is updated to Solaris 11 ?? |
This one was flagged in a random tag wiki editing I was doing: I totally agree it's a useless tag. If anyone is curious as to what anti-golf supposedly is, before putting on my burninate useless tags cap, I'd come up with this: Anti-golf is a hypothetical programming game, with the objective being opposite to that of code golf. The real and popular code golf programming game, involves finding solutions in code to problems using the minimal amount of characters. Anti-golf is a suggested counter model to the common game, by implementing rules such as requiring longer code and ensuring the program will fail if any single character is removed. First evidenced proposal of the game was in 2002, by Peter Makholm on the Perl Programming lists. | During the re-tagging of questions, tags sometimes become orphaned from existing questions. Are these zombie tags ever removed from the ? What if a tag is misspelled and needs to be removed? How do we get rid of it? |
I have finally figured out how to validate inserted russian text in my tag by mask = jQuery.extend({unitprmask:/^\d+(\.\d{1,1})?$/,expressmask:/^\d+(\.\d{1,1})?$/,qtymask:/^\d+(\.\d{1,1})?$/,yourdescdmask:/^[а-яА-Я\p{Cyrillic}0-9\s\-]{1,10}$/,URLmask:/^(https?|ftp):\/\/(.*)[a-z0-9]+([\-\.]{1}[a-z0-9]+)*\.[a-z]{2,5}(:[0-9]{1,5})?(\/.*)?$/}); But I want to allow users to write in the in mixed languages " Russian + Persian + Chinese + English". how can I make it happened using regex? what should I add to the above code, I have tried to add a-zA-Z to validate english letters but i wasn't successful. I am actually not able to add other languages, the one I wrote yourdescdmask:/^[а-яА-Я\p{Cyrillic}0-9\s\-]{1,10}$/ will allow Russian text only. Could you please help me out here? Thanks | What is the easiest way to match non-ASCII characters in a regex? I would like to match all words individually in an input string, but the language may not be English, so I will need to match things like ü, ö, ß, and ñ. Also, this is in Javascript/jQuery, so any solution will need to apply to that. |
There used to be a way where if you opened an app in Full Screen and then quit, it would reopen in full screen. However in Yosemite, I don't know how to do this for full screen apps. Is there a way to do this in Yosemite? | I quite like using full-screen apps on OSX Mavericks (Safari, iTunes, Mail, etc). I'd like all apps that are capable of running full-screen to launch in full-screen mode automatically, instead of me having to press Ctrl-Cmd-F each time, is that possible? |
It is often advised to use non-WWW url, so that there is less redirects and link juice does not leak, since people most often type non-WWW urls. But who cares what the user types? Links are not indexed from what user type into the address bar but what can be found on the web in form of anchor tags right? Some of those tags you got a control over (your own website, advertisement,..). The others are typed by users, yes, but they are parsed by the service, where the user types them - Facebook etc. For Facebook to recognize text as a URL, you have to use www. prefix and many other services auto prepend www too. So correct me if I am wrong, but most links, that you have no control over, are WWW variants and therefore from a perspective of SE crawler, running WWW version of your site will produce less 301s. User typing the url into his browser will get one more 301 from non-WWW to WWW, but that has no relevance to page rating. | I remember reading ages ago that it's a good idea to choose either www.example.com or domainexamplecom as your main URL and then set the other one as a 301 redirect to point to your domain? The reason provided was: Some people may link to www.example.com Other links may point to example.com In order to not lose 'SEO link juice', the individual recommended setting up a 301 redirect from one to the other. Has this changed? Is it true? I would have guessed that Google (and other search engines) would be smart enough to whack some code in their algorithm to understand that in most cases www.example.com = example.com? |
What is the difference between virtual object and virtual image? | I'm doing magnification and lens in class currently, and I really don't get why virtual and real images are called what they are. A virtual image occurs the object is less than the focal length of the lens from the lens, and a real image occurs when an object is further than focal length. By why virtual and real? What's the difference? You can't touch an image no matter what it's called, because it's just light. |
I have a dataset of roughly 1000 subjects' data and their labels. The ultimate goal is to build a neural network which can classify the data as either 0 or 1. My current strategy is to do 10-fold CV, wherein I take a different 10% of the data for testing while training on the remaining 90% (repeated many times). There are many hyperparameters (hidden layer size, net type, etc) which I am optimizing based on the average accuracy of the 10-folds. So at the end of this, I've obtained the best hyperparameters to get the highest average accuracy. When it is time to actually use this classifier on new data, which model do I use? If my training set is now those 1000 datapoints, then my previously optimized hyperparameters are no longer optimal for that training set. I may have a fundamental misunderstanding of k-fold, but if not then how do I go about doing this (designing a classifier with labels to be used on unlabeled data in the future)? | There are numerous threads in CrossValidated on the topic of model selection and cross validation. Here are a few: @DikranMarsupial's to However, the answers to those threads are fairly generic and mostly highlight the issues with particular approaches to cross validation and model selection. To make things as concrete as possible, say for example that we are working with an SVM with an RBF kernel: $K(x, x' ) = (\gamma \, \vert x - x'\vert)^2$, and that I have a dataset of features X and labels y, and that I want to Find the best possible values of my model ($\gamma$ and $C$) Train the SVM with my dataset (for final deployment) Estimate the generalization error and the uncertainty (variance) around this error To do so, I would personally do a grid search, e.g. I try every possible combination of $C$ and $\gamma$. For simplicity, we can assume the following ranges: $C \in \{10, 100, 1000\}$ $\gamma \in \{0.1, 0.2, 0.5, 1.0\}$ More specifically, using my full dataset I do the following: For every ($C$,$\gamma$) pair, I do repeated iterations (e.g. 100 random repetitions) of $K$-fold cross validation (e.g. $K=10$), on my dataset, i.e. I train my SVM on $K-1$ folds and evaluate the error on the fold left, iterating through all $K$ folds. Overall, I collect 100 x 10 = 1000 test errors. For each such ($C$,$\gamma$) pair, I compute the mean and the variance of those 1000 test errors $\mu_M, \sigma_M$. Now I want to choose the best model (the best kernel parameters) that I would use to train my final SVM on the full dataset. My understanding is that choosing the model that had the lowest error mean and variance $\mu_M$ and $\sigma_M$ would be the right choice, and that this model's $\mu_M$ are $\sigma_M$ are my best estimates of the model's generalization error bias and variance when training with the full dataset. BUT, after reading the answers in the threads above, I am getting the impression that this method for choosing the best SVM for deployment and/or for estimating its error (generalization performance), is flawed, and that there are better ways of choosing the best SVM and reporting its error. If so, what are they? I am looking for a concrete answer please. Sticking to this problem, how specifically can I choose the best model and properly estimate its generalization error? |
Say $R$ is a ring, and $I_1,...,I_n,J\subseteq R$ ideals, s.t $J\subseteq\bigcup_{i=1}^nI_i$. If there exists $\phi:K\rightarrow R$ homomorphism where $K$ is an infinite field, then there exists an $i$ s.t $J\subseteq I_i$. I split it into two cases: Since $\phi$ is an homomorphism and $K$ is a field, then $\phi^{-1}(J)=\langle0 \rangle $ or $\phi^{-1}(J)=K$. If it's the first case, then since $\phi$ is injective (since $K$ is a field) we then get that $J=\langle 0 \rangle$ and obviously for every $i$, $J\subseteq I_i$. Now, if $\phi^{-1}(J)=K$, then there must be at least one index $i$ s.t $\phi^{-1}(I_i)=K$ - otherwise the union is $\bigcup_{i=1}^n I_i=\langle 0 \rangle$ - contradiction since $J\neq\langle 0 \rangle$. So I can see that $\phi(\phi^{-1}(J))\subseteq \phi(\phi^{-1}(I_i))$, but this doesn't immediately mean that $J\subseteq I_i$ - even with $\phi$ being an injection. What am I missing here? Any help would be appreciated. | Let $R$ be a ring and let $I_1,\dots,I_n,J\subseteq R$ be ideals such that $J\subseteq I_1\cup\dots\cup I_n$. Suppose that there exists an infinite field $K$ and a homomorphism $\phi:K\to R$. Prove that $\exists k$ s.t. $J\subseteq I_k$. Attempt: (Edited) If $J\subseteq I_1$ then we're done. Otherwise, let $x\in I_1$ and let $y\in J\setminus I_1$. $\forall r\in K, x+ry\notin I_1$ (because otherwise we'll get $y\in I_1$). $K$ is infinite so we have infinitely many elements of the form $x+ry\in J$. So there's some $k$ for which $I_k$ contains infintely many elements of the former form. If $n=2$ so $x+y\notin I_1$ implies $$x+y\in I_2\Rightarrow x\in I_1\Rightarrow I_1\subset I_2\Rightarrow J\subseteq I_2$$ Suppose the theorem holds for some $n$. $x+y\notin I_1\Rightarrow \exists k,I_k\ni x+ry$ for infintely many elements as above. |
I didn't notice it until recently, but apparently we have a tag. IMHO it's rather pointless; as you may guess, This tag is for questions about the entire network of Q&A sites that make up the Stack Exchange network. Well, this entire site is questions (and answers) about the entire network of Q&A sites that make up the Stack Exchange network. I think we can safely say that if a question can't be tagged with it's off-topic here. The major problem is that 1.5k questions have this tag, so a manual burninate process will be very cumbersome. There is without a doubt a magic script to remove the tag for all questions (without bumping them), but I can imagine the CMs/devs don't want to run it because it would set a precedent. Still, this might be a case where it's worth it. | It looks like the tag (later renamed to ) is a holdover from the pre-split days when this site was called Meta Stack Overflow and also served as the meta site for Stack Overflow (in addition to its current purpose). It was intended to disambiguate questions about the SE network as a whole from questions specifically about Stack Overflow (). It has nearly 1,500 uses, so it's too big to clean up manually. It looks like people are still using it on new questions, and I just saw a suggested edit that only added this tag. Since all questions here should be about Stack Exchange, can we burninate this, the ultimate meta tag? |
I often see statements in discussions about web displayed image quality that go something like this: "I only upload pictures at 72 dpi and 1200 pixels on the long edge, so if someone copies and prints the image it won't look as good as if it were 300 dpi." What? Have I missed something here? Does an image edited and saved/exported with 1200x800 pixels at 300 ppi look any different online than the same image saved/exported with 1200x800 pixels at 72 ppi? Other than the metadata regarding ppi, is there any difference in the two images at all? If so, what is the difference? If I tell my printer to print the images at 4R (4X6 inches) will there be any difference at all in how the printer creates a print from the 1200x800 @ 300 dpi image versus the 1200x800 @ 72 dpi image? | I have two cameras, a 6mpix Panasonic FZ8, and 14mpix Canon A2200. When I compare shots from two cameras, one of differences I notice is dpi number that camera reports in JPG info: FZ8 reports dpi=72 A2200 reports dpi=180 What physical meaning can these numbers have? I am at loss for guesses. I am fairly familiar with notion of dpi in scanning and printing. I can calculate density of pixels on the sensor of the camera. But then, the linear density of pixels on the sensor will be hundreds times larger than number above. So what, if anything, does it mean? |
There is now a 3-day limit for the HNQ. But what was the longest amount of time that a question stayed on the HNQ for prior to that limit being instituted? I'd imagine some questions having stayed on the HNQ for well over a week. | Right now there are multiple questions that have been on the Hot Network Questions list for a large number of days: 8 days - 8 days - 7 days - 5 days - 5 days - There are also seven that have been there for four days. I do not see what value a question sitting on the HNQ has when it is there over a week. They clog the HNQ and make it harder for other questions to get there, lowering overall exposure to other sites. They also disproportionately give reputation to users on those sites who have answers there, which results in a dilution of the meaning of reputation. It is also not uncommon for questions to stay there this long. My recommendation is a simple change to add a hard cutoff that when a question is more than 72 hours (3 days) old, it no longer is present in the HNQ list. This would be as simple as adding a date filter into the query generating the list - the hotness formula itself doesn't need to change in order to effect this result. The goal of this suggestion is not any of the following: Comprehensively fixing HNQ (there are other problems with it) Revamping the calculation Imposing site limits/etc It is purely to add a basic and simple filter to the query in order to more quickly cycle questions through the list. Note: |
It has been known that USB Storage functionality was removed in Android 4.4.x and subsequent version of Android. PTP doesn't work very well on cross-platforms, not to mention it restricts files to certain media types. MTP works in Windows and in some Linux distributions with certain tweaks. However, it is not very stable and breaks often when transferring huge files (on all of my three Android devices). The question is to suggest some good alternatives for file transfer between Desktop and Android without compromising data transfer speed (via USB cable). It implies that no data transfer apps using hotspot/wifi should be suggested like Airdroid, WeLine, Webkey et al. Note that the solution should work on at least all of the Android 4.x.x versions and possibly on 5.0 too. A similar question was asked but its limited to Android 4.0.x. | Since the latest versions (ICS+?) no longer have mass storage, is there any viable alternative to MTP? The protocol seems inherently broken and the decision to regress to this format seems like a very 'iphone-esque' move (dumb things down, take away power from the users). There seem to be numerous problems with files not showing and it seems to me that transferring a file should be simpler than requiring a system reboot - I am unreasonably demanding that way. I'm aware of tools like Wi-Fi file transfer but often I find myself in areas without wifi, with just my laptop, phone and a usb cable. The other day, for example, I was one a plane, which is an environment decidedly non-conducive to using a wireless system. |
Process: com.example.vicevirus.myapplication, PID: 13471 java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.String com.google.firebase.auth.FirebaseUser.getUid()' on a null object reference at com.example.vicevirus.myapplication.RegisterActivity$1.onComplete(RegisterActivity.java:48) at com.google.android.gms.tasks.zzc$1.run(Unknown Source) at android.os.Handler.handleCallback(Handler.java:751) at android.os.Handler.dispatchMessage(Handler.java:95) at android.os.Looper.loop(Looper.java:154) at android.app.ActivityThread.main(ActivityThread.java:6119) at java.lang.reflect.Method.invoke(Native Method) at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:886) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:776) This is on android monitor. How do I solve this? package com.example.vicevirus.myapplication; import android.app.ProgressDialog; import android.support.annotation.NonNull; import android.support.v7.app.AppCompatActivity; import android.os.Bundle; import android.view.View; import android.widget.EditText; import android.widget.Toast; import com.google.android.gms.tasks.OnCompleteListener; import com.google.android.gms.tasks.OnSuccessListener; import com.google.android.gms.tasks.Task; import com.google.firebase.auth.AuthResult; import com.google.firebase.auth.FirebaseAuth; import com.google.firebase.database.DatabaseReference; import com.google.firebase.database.FirebaseDatabase; public class RegisterActivity extends AppCompatActivity { private EditText email,name,password; DatabaseReference databaseReference; FirebaseAuth mAuth; private DatabaseReference userIdRef; ProgressDialog registerDialog; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_register); email=(EditText)findViewById(R.id.email); name=(EditText)findViewById(R.id.name); password=(EditText)findViewById(R.id.password); databaseReference= FirebaseDatabase.getInstance().getReference().child("chat_users"); mAuth=FirebaseAuth.getInstance(); registerDialog=new ProgressDialog(this); registerDialog.setMessage("Registering.."); } public void submit(View view) { registerDialog.show(); mAuth.createUserWithEmailAndPassword(email.getText().toString(),password.getText().toString()).addOnCompleteListener(this, new OnCompleteListener<AuthResult>() { @Override public void onComplete(@NonNull Task<AuthResult> task) { if(task.isComplete()) { registerDialog.dismiss(); Toast.makeText(getApplicationContext(),"Registered successfully",Toast.LENGTH_SHORT).show(); userIdRef=databaseReference.child(mAuth.getCurrentUser().getUid()); userIdRef.child("name").setValue(name.getText().toString()); finish(); } registerDialog.dismiss(); } }); } } | What are Null Pointer Exceptions (java.lang.NullPointerException) and what causes them? What methods/tools can be used to determine the cause so that you stop the exception from causing the program to terminate prematurely? |
Australia to South Africa to Morocco. All travels are 4-5 days apart. So which ticket do I book with which passport? Which passport do I use to enter and exit to the next country? | I am a citizen of two different countries, and have two passports. How should I use my passports when traveling? |
I finally went and got my Ham Radio licence. I've been reading about how radio operators use the ionosphere for long distance communication through ionic reflections of transmitted/received EM waves. I'm trying to visualize how this happens, so that I have more intuition into what frequencies to use under various conditions of the ionosphere. Can someone give an illustration of how EM waves are reflected by ions in the ionosphere, to help convey pictorially why wavelength matters? | says: ... Unlike high frequencies (HF), the ionosphere does not usually reflect VHF waves (called skywave propagation) so transmissions are restricted to the local radio horizon less than 100 miles... Why does this happen? Is it merely that a VHF signal of say, 100Watts, carries more energy than an HF signal of the same power? Are there any other factors in play here? |
I've already read the answers to this , but they were written so long ago that I wonder if some progress has been made on the subject since then. I would like to know if there's some more objective way to choose the correlation or covariance matrix to do PCA than «careful thought and some experience» or «similar scales»? Any help would be appreciated. Edit: I asked this because there could be maybe some measure, and a respective scale of interpretation for when to use a covariance or correlation matrix. In statistics, we can observe some examples of this like for bayes factors, p-values, or at least an interpretative comparison like what happens with AIC or BIC, albeit these measures are for different objectives than the one I'm searching. | What are the main differences between performing principal component analysis (PCA) on the correlation matrix and on the covariance matrix? Do they give the same results? |
I always prefer keeping my disk optimized by using the above command. I wanted to know whether this is a safe practice. I am using Ubuntu 16.04 | The last time I used sudo apt-get autoremove, nearly every important display driver or parts got deleted. This made me very squeamish about using the command again. However, each time I install something or use apt-get update the terminal reads: The following packages were automatically installed and are no longer required: devilspie libturbojpeg:i386 libxrandr-ltsr2 language-pack-kde-en kde-l10n-engb language-pack-kde-en-base libxv1:i386 libllvm3.2 libllvm3.2:i386 linux-generic-lts-raring Use 'apt-get autoremove' to remove them. I tried the command clean and the messages stops displaying for a while. My question is whether it's safe running the autoremove command, or will I lose everything once again? Is there a way of checking how safe it is to use autoremove in this particular (or any) case? |
When I navigate to the "Unanswered" section, it displays a list of questions, but those questions have answers. What does "unanswered" question actually mean? 0 answers OR user yet to accept the answer? I found it the answer: "questions with no upvoted answers" | Why does the "Unanswered Questions" tab show questions that have answers? |
For some reasons i am trying to Redirect all traffic coming to port 443 to port 80 i.e from https to http and kindly this is not duplicate because i searched a lot but did not found any working solution. I created the following .htaccess file in root folder RewriteEngine On RewriteCond %{SERVER_PORT} 443 RewriteRule ^(.*)$ http://www.localhost.com/$1 [R,L] this is not working but my .htaccess file is being read correctly i confirmed it by running following tests I put random garbage character and Server shows error 500 The reverse of above code is working i.e Properly redirecting from http to https If any one has experienced this before then kindly guide me to the solution Best Regards! | I used to operate a website with an SSL certificate, but have stopped using the SSL certificate. The problem is that most of the external links to the website use the https:// prefix. I have tried the https:// to http:// redirect in the .htaccess file: RewriteEngine On RewriteCond %{HTTPS} on RewriteRule ^(.*)$ http://%{HTTP_HOST}%{REQUEST_URI} But it seems, as has been pointed out elsewhere, that the server is trying to retrieve the certificate before activating the redirect. Hence, an error is shown before the redirect is ever accomplished. The error is either a warning that the certificate is expired, or if I delete the certificate signing request, then an error that SSL received a record that exceeded the maximum permissible length. Is there any way to allow the incoming links to be redirected properly? |
I have tried everything and i have been on this for two days, no progress. i can access the same server (hadoopmaster) but when i try to copy the key or ssh into the slave (hadoopslave-1) i get the permission denied (publickey) error. Am here to get help. Because i want to make them to be able to ssh into each other one namenode and two datanodes , i have already installed ambari and trying to setup on ambari on the cluster. i used ssh -i ~/.ssh/id_rsa -v [email protected] Also tried to copy key but same error message ssh-copy-id -i $HOME/.ssh/id_rsa.pub ubuntu@hadoopslave-1 | I have an instance of an application running in the cloud on Amazon EC2 instance, and I need to connect it from my local Ubuntu. It works fine on one of local ubuntu and also laptop. I got message "Permission denied (publickey)" when trying to access SSH to EC2 on another local Ubuntu. It's so strange to me. I'm thinking some sort of problems with security settings on the Amazon EC2 which has limited IPs access to one instance or certificate may need to regenerate. Does anyone know a solution? |
What's the difference between and using hibernate and sessionFactory? | Hibernate has a handful of methods that, one way or another, takes your object and puts it into the database. What are the differences between them, when to use which, and why isn't there just one intelligent method that knows when to use what? The methods that I have identified thus far are: save() update() saveOrUpdate() saveOrUpdateCopy() merge() persist() |
Let $R$ be a commutative ring with a multiplicative identity. If $a\in R, a \not = 0$, prove that $R/(a)$ is not a free $R$-module. My initial attempt was to say that R/(a) is not torsion free, thus it cannot be free, but then I realized that the theorem "M is a free module if and only if it is torsion free" only works for finitely generated modules over PIDs. So I'm pretty lost as to how to prove this. Any help would be appreciated! | Let $R$ be a commutative ring with $1$ and let $J$ be a proper ideal of $R$ such that $R/J \cong R^n$ as $R$-modules where $n$ is some natural number. Does this imply that $J$ is the trivial ideal? Basically I am trying to prove/disprove that if $J$ is a proper ideal of $R$ and $R/J$ is free then $J=0$ and above is my work. |
Show that $\mathbb{C}$ and $\mathbb{R[x]}/\langle x^2+1\rangle$ as $\mathbb{R}$-Algebras are isomorphic. This is the first time that we are dealing with polynomial rings and algebras so i am a bit confused. The first problem is that I can't wrap my head around what elements of $\mathbb{R[x]}/\langle x^2+1\rangle$ are. I kinda understand theoretically but can't practically. The second problem is to find the isomorphism. Now if $\langle x^2+1\rangle$ is an Ideal of $\mathbb{R[x]}$ then I guess there is a theorem which implies that they are isomorphic. Si it remains only to show that it is an ideal? Thanks in advance | Show that $\Bbb R[x] / \langle x^2 + 1 \rangle$ is isomorphic to $\Bbb C$. Let $\phi$ be the homomorphism from $\Bbb R[x]$ onto $\Bbb C$ given by $f(x) \rightarrow f(i)$ (that is, evaluate a polynomial in $\Bbb R[x]$ at $i$). Then $x^2 + 1 \in \operatorname{Ker} \phi$ and is clearly a polynomial of minimum degree in $\operatorname{Ker} \phi$. Thus, $\operatorname{Ker} \phi = \langle x^2 + 1 \rangle$ and $\Bbb R[x] /\langle x^2 + 1 \rangle$ is isomorphic to $\Bbb C$. My question is: How is $x^2 + 1$ a polynomial of minimum degree in $\operatorname{Ker} \phi$? |
I have the following code: typedef struct { int a; int b; } Hello; typedef struct { char c; int d; } World; Hello hello[10][10]; World world[5]; Then I have the following functions: void getInfo(Hello hello_p[][10], World* world_p) { // Here I suppose to get the size of pointer to the array of hello and world sizeof(hello_p); sizeof(world_p); } void getHello(Hello (** hello_p)[10]) { hello_p = hello; } void getWorld(World ** world_p) { world_p = world; } then I call the function like: Hello (*hello_p)[10] = NULL; World *world_p = NULL; getHello(&hello_p); getWorld(&world_p); getInfo(hello_p, world_p); then in the getInfo function, can I get the size of the pointer to the array of hello and world? | 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)? |
I have a dual boot with Ubuntu and Windows and I trying to make a Linux partition bigger, but I can't. | Previously, I have installed Windows 7 on my 320 GB laptop with three partitions 173, 84 and 63 GB each. The 63 GB partition was where the Windows was installed. The rest were for file containers. Now I changed my OS to Ubuntu 12.04 LTS. I installed Ubuntu by replacing the entire Windows 7 on the 63 GB partition. The rest of the partitions remain as an NTFS Windows partition and I can still access them both (the 173 and 84 GB partitions). Now I want to change the two partitions of Windows into an Ubuntu format partitions plus most importantly, I want to extend the 63 GB partition to more than a 100 GB because at the moment I am running out of disk space. Whenever I try to install any application, especially using wine, it always complains for a shortage of disk space. How do I do the extending activity before I entirely format my laptop again and lose all the important files on my partitions? |
I am using joshcam/ PHP MySQLi class and currently having problem on inserting foreign character in the table. I tried to update using rawQuery to identify if the problem lies with the class itself. $db->rawQuery("UPDATE table SET fieldname=''龙岗区中心" WHERE . ..... "); The query executes with no problem but it saves as ?????? in the table. If i use mysql_query update on the same table , the characters insert in the table with no problem. Has anyone experienced this? The charset is set as UTF-8. Any help would be much appreciated. Regards Ash | 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. |
Is it correct to say "The list of reports a user will see may depend on the permissions group(s) they are in."? I have asked the writer to change the text to say "users" to match "they", but he is resisting. | Is this sentence grammatically correct? Anyone who loves the English language should have a copy of this book in their bookcase. or should it be: Anyone who loves the English language should have a copy of this book in his or her bookcase. |
Choose a random number between 0 and 1. Add it to 0. Choose another random number between 0 and 1 and add it to your previous sum. If your sum exceeds 1, stop, otherwise continue the same process. Store the number of choices you had to make. It seems that the average(total choices divided by total iterations) converges to $e$. Here is an equivalent Python code: import random Total_choices=0 Tries=1 choices=0 Total=0 iterations=1000 while Tries<=iterations: while Total<1: Total=Total+random.uniform(0,1) choices=choices+1 Total=0 Total_choices=Total_choices+choices choices=0 Tries=Tries+1 print(Total_choices) print(Total_choices/iterations) Following are some examples of outputs that I got from which I hypothesized the above statement: Iterations=100 average=2.62 Iterations=1000 average=2.752 Iterations=10000 average=2.7131 Is my hypothesis correct? If yes then why does this happen? P.S if you can suggest a more appropriate title and I thought perhaps this question is more appropriate for this community instead of | I define $X_i$ as a random variable that is uniformly distributed between (0,1). What is the expected number of such variables I require to make the sum go just higher than 1. Thanks |
I have to prove that. While I know this is true by thinking about it I'm having a lot of trouble actually writing the proof how can I prove $A\setminus(B\setminus C) = (A \setminus B) \cup (A \cap C)$ first of all it's true? | I have to prove that. While I know this is true by thinking about it I'm having a lot of trouble actually writing the proof |
I have looking at reasons for why my Yongnuo YN560IV would not fire at Highspeed sync on my Nikon D750. I tried some setups, but whenever I go further up than 1/250s shutter speed, the flash won't do the high-speed sync. It will not burst the flash at all, only a single flash. Any idea why? | I recently bought myself a pack of four YN560 IV's and a YN560-TX for my Canon camera, and apparently I got ahead of myself and didn't realise I should make sure the flashes support HSS. I tried them out yesterday at home, and even on 1/128 and 1/250s on the camera, they were overexposing here and there. Unfortunately, I don't really have the space to move the flashes much further from my subject, so I was wondering if there is any way to trick them into HSS? I should mention that I also own a Canon 580ex II, which does support HSS. I was thinking I could perhaps use that mounted on the camera to trigger the Yongnuo's, but as far as I can tell that would render the 560-TX useless as the flashes can't be controlled wirelessly when in S1 or S2. I guess I could buy an ND filter, but as I have lenses with differing sizes, this feels like more of a pain in the ass. Is there any hack I can pull off here that you guys know of? Thanks! |
I wrote a python script to autogenerate a background pattern for my computer. I want to use cron to run it every 15 minutes or so. Here's the code: #!/usr/bin/python import os import numpy as np import svgwrite as svg WIDTH = 1600 HEIGHT = 900 def circle_layer(dwg, size_range, blur, number): blur_filter = dwg.defs.add(dwg.filter()) blur_filter.feGaussianBlur(in_='SourceGraphic', stdDeviation=blur) g_f = dwg.add(dwg.g(filter=blur_filter.get_funciri())) for c in xrange(0, number): (x, y) = (np.random.random_integers(0,WIDTH), np.random.random_integers(0,HEIGHT)) rad = np.random.random_integers(size_range[0], size_range[1]) g_f.add(dwg.circle(center=(str(x),str(y)), r=str(rad),stroke="rgb(100,100,100)", fill="rgb(100,0,0)")) return dwg if __name__ == "__main__": svg_doc = svg.Drawing(filename = "current_wallpaper.svg", size = (str(WIDTH), str(HEIGHT))) svg_doc.add(svg_doc.rect(insert=(0,0), size=(str(WIDTH), str(HEIGHT)), fill="rgb(0,0,0)")) svg_doc = circle_layer(svg_doc, (10,50), 20, 100) svg_doc = circle_layer(svg_doc, (10, 20), 4, 100) svg_doc.save() import subprocess proc = subprocess.Popen(["pgrep gnome-session"], stdout=subprocess.PIPE, shell=True) (pid, err) = proc.communicate() pid = pid.rstrip('\t\r\n\0') print repr(pid) cmd = "grep -z DBUS_SESSION_BUS_ADDRESS /proc/"+pid+"/environ|cut -d= -f2-" proc = subprocess.Popen([cmd], stdout=subprocess.PIPE, shell=True) (out, err) = proc.communicate() out = out.rstrip('\t\r\n\0') print repr(out) cmd = "export DBUS_SESSION_BUS_ADDRESS=$"+out print repr(cmd) os.system(cmd) os.system("/usr/bin/gsettings set org.gnome.desktop.background picture-uri file:///home/jofo/Pictures/Wallpapers/current_wallpaper.svg") print "I ran!" Basically, it uses svgwrite to draw some circles and add a gaussian blur. Then, I make a system call to gsettings to update the ubuntu wallpaper. This works fine when I run it as ./wallpaper.py, but when I schedule it in crontab, the script runs, and the background pattern doesn't change. Here's what I have in my crontab file doohickey: MAILTO="" */1 * * * * /home/jofo/Pictures/Wallpapers/./wallpaper.py >> /home/jofo/Pictures/Wallpapers/cron.log I know the script is running once a minute because it appends "I ran!" to the cron.log file once per minute. Unfortunately, the wallpaper never changes. If anyone knows why this might be, that would be great! | I'm trying to change my wallpaper to a random image using Indrajith Indraprastham's suggested script here: When I run the script from a terminal window, the bg changes just fine, but when it's run from cron, I'm mailed this error: (process:21901): dconf-WARNING **: failed to commit changes to dconf: Error spawning command line 'dbus-launch --autolaunch=00216c114dcf433c9bb9009985d607d6 --binary-syntax --close-stderr': Child process exited with code 1 I would appreciate any suggestions. |
I need to calculate the age of a person taking in consideration the years, months and days to check if the person is under 14 or not.The return result should be boolean if the person is under 14 or not. I tried with this code but I'm getting an error of conversion. var under14 = false; string person.DateOfBirth = "04/01/2012"; var DateOfBirth = Convert.ToInt32(person.DateOfBirth); var ageDifMs = Convert.ToInt32(DateTime.Now) - DateOfBirth; var ageDate = new DateTime(ageDifMs); var age = Math.Abs(ageDate.Year - 1970); if (age < 14) under14 = true; | Given a DateTime representing a person's birthday, how do I calculate their age in years? |
I'm trying to solve the second part of the following exercise which is question 32 in Section 1.5 of Real Analysis by Folland. Suppose $\{\alpha_j\}_{j=1}^{\infty} \subset (0, 1)$. Then: $\prod_{j=1}^{\infty} (1 - \alpha_j)>0$. if and only if $\sum_{j=1}^{\infty} \alpha_j < \infty$. Given $\beta \in (0, 1)$, exhibit a sequence $\{\alpha_j\}_{j=1}^{\infty}$ such that $\prod_{j=1}^{\infty} (1 - \alpha_j)= \beta$. How can I prove the second part of the statement? I am pretty sure that it should be solved by induction. But I don't know how to do it. | Suppose $\{\alpha_j\} \subset (0,1)$. Give a sequence ${\alpha_j}$ such that $\prod (1-\alpha_j) = \beta $, where $\beta \in (0,1)$ I was able to prove part a. That is the infinite product of $(1-a_j)$ is positive iff $\sum \alpha_j < \infty $. However, I have no idea how to exhibit a sequence ${a_j}$ so that the infinite product of $1-\alpha_j$ is some $\beta$ that is in $(0,1)$. Would I need to construct a specific sequence or a more general case? Any help would be much appreciated as I am really stuck and don't have much of an idea even where to begin. |
G is a group and N a subgroup of G, and if index of N in G is 2, then N is Normal. Can someone please explain why? | $\\$ A normal subgroup $N$ is a subgroup where the left cosets are the same as the right cosets. $N$ is normal $\iff $ $xnx^{-1} \in N, \forall x\in G$. 5.) Why is it that if $[G:H]=2 \implies $ $H$ is normal subgroup? 6.) Can we say that a factor group is just a group that has left cosets of $N$ (being a normal subgroup) as its elements? So if $N$ is a normal subgroup, then the left cosets of $N$ forms a group under coset multiplication given by $aNbN = abN$. 7.) The group of left cosets of $N$ in $G$ is called the factor group, why do we denote this by $G/N$? These are the same things as the integers modulo $n$ groups? How can I relate those exactly? |
Here is a conundrum I pondered upon while solving an equation - 2x2 , generally means we are adding 2 two times , that is , 2+2 Then , (-2)x(-2) , should go like this (-2)+(-2)=-4 , But , that's not true , the answer is +4 . Can anybody figure out and help me with it.. | How to logically understand the multiplication of two integers ? Eg: 3 x 4 = 12 (is understandable) -3 x4 = -12 (is also somewhat understandable) But , 3 x -4 = -12 (is NOT understandable) -3 x -4 = 12 (is also NOT understandable) Now , at this we must assume that commutative property may not be true . What is the logical explanation for something being multiplied negative times ? |
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