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Would you use past perfect in following sentence or would you rather go with other tense? It had been here before we came. | Example 1 I've lived here all my life, and I've been through quakes before. But this one felt different — not because of how big it was, but because of all the bad things that happened before. Example 2 It was 8:30. My brother had arrived 3 hours before. Why does the first sentence use past simple and the second use past perfect? I thought with "before" it was not obligatory to use past perfect. Is it because, in the first sentence, there is no logical relation between the bad things and the quakes? That is: the bad things did not cause the quakes. In the second sentence, both events are compared. Is that why past perfect is used? |
I know the series $$\sum_{k=1}^\infty \frac{(\frac{1}{10})^{k+1}}{k(k+1)}$$ is equal to $$\frac{1}{10}-\frac{9}{10}\ln \Big(\frac{10}{9}\Big)$$ but how would I use the ratio test to show this is true? I also know that: $$ (1-x)\ln(1-x)=\sum^\infty_{k=1}\frac{x^{k+1}}{k}-\sum^\infty_{k=1}\frac{x^k}{k} =\sum_{k=1}^\infty \frac{x^{k+1}}{k(k+1)}$$ | Find the sum of $\sum\limits_{n=1}^{\infty} \frac{x^{n}}{n(n+1)}$ on its domain of convergence. This is my idea. We have the radius of convergence is $R=1$. And $\sum_{n=1}^{\infty} \dfrac{x^{n}}{n(n+1)}=\dfrac{1}{x}\cdot \sum_{n=1}^{\infty} \dfrac{x^{n+1}}{n(n+1)}$. Then let $f(x)=\sum_{n=1}^{\infty} \dfrac{x^{n+1}}{n(n+1)}$. We have $f'(x)=\sum_{n=1}^{\infty} \dfrac{x^{n}}{n}$ and $f''(x)=\sum_{n=1}^{\infty} x^{n-1}=\dfrac{1-x^n}{1-x}$ Then if I take the primity of $f''(x)$, I get: $f'(x)=\displaystyle\int\limits_{0}^{x}\dfrac{1-t^n}{1-t}\mathrm{d}t=-\ln(1-x)-\displaystyle\int\limits_{0}^{x}\dfrac{t^n}{1-t}\mathrm{d}t$ Then I will get a sum again, and that's not the goal. What can I do then? Thank you so much. |
I am presently 30 days away from earning the gold ; however, in retrospect, I feel that this badge, and the silver , when compared to other silver and gold badges, are far too easy to attain. In my opinion, the difficulty of the Enthusiast badge should make it a bronze badge, not silver, and the Fanatic badge a silver, not gold. My perspective is that a gold badge should be something that takes a considerable amount of dedication, effort, and/or hard work to attain, just like all of the other gold badges. If you look at our present numbers, there are over 64,000 people that have earned the Enthusiast badge, and well over 10,000 that have earned the gold Fanatic badge. And when you compare these numbers to many of the other silver and gold badge, the numbers just don't line up. I'm not expecting a 1:1 relationship here, but I am expecting to see a similar pattern of a low percentage of people earning the gold badge; however, in this case, there are many more people earning the gold Fanatic badge, than there are people earning many of the silver badges! It's just way to skewed IMO. So, I have the following suggestions to remedy this: Enthusiast badge: Change from Silver to Bronze, keeping the existing requirement, "Visited the site each day for 30 consecutive days." Fanatic badge: Change from Gold to Silver, keeping the existing requirement, "Visited the site each day for 100 consecutive days." Add a new gold badge: Possible names: A. "Devoted" B. "Dedicated" C. "Habitual" D. "Zealous" Eligibility: "Visited the site each day for 365 consecutive days." I feel that this change will put these new bronze, silver, and gold badges in alignment with many of the other badges in regards to difficulty and/or amount of effort. | : Silver Enthusiast Visited the site each day for 30 consecutive days 56.9k awarded Bronze Mortarboard Earned at least 200 reputation in a single day 15.4k awarded It would seem that earning Enthusiast requires almost no effort while Mortarboard is highly non-trivial. This appears to be reflected in the award count (almost 4:1 in favor of enthusiasts). So, why is the first one silver and the second one bronze? (A similar question can be asked about Epic vs Fanatic and probably many other). |
$|N| = |N \times N|$ ($N \times N$ countable) I tried to build a bijective function $f(n,m) \to n$. I saw some posts about this question but there wasn't any example nor a good explanation. | I'm examining a proof I have read that claims to show that the Cartesian product $\mathbb{N} \times \mathbb{N}$ is countable, and as part of this proof, I am looking to show that the given map is surjective (indeed bijective), but I'm afraid that I can't see why this is the case. I wonder whether you might be able to point me in the right direction? Indeed, the proof begins like this: "For each $n \in \mathbb{N}$, let $k_n, l_n$ be such that $n = 2^{k_n - 1} \left(2l_n - 1 \right)$; that is, $k_n - 1$ is the power of $2$ in the prime factorisation of $n$, and $2 l_n - 1$ is the (necessarily odd) number $\frac{n}{2^{k_n - 1}}$." It then states that $n \mapsto \left(k_n , l_n \right)$ is a surjection from $\mathbb{N}$ to $\mathbb{N} \times \mathbb{N}$, and so ends the proof. I can intuitively see why this should be a bijection, I think, but I'm not sure how to make these feelings rigorous? I suppose I'd say that the map is surjective since given any $\left(k_n , l_n \right) \in \mathbb{N} \times \mathbb{N}$ we can simply take $n$ indeed to be equal to $2^{k_n - 1} \left(2l_n - 1 \right)$ and note that $k_n - 1 \geq 0$ and thus $2^{k_n - 1}$ is both greater or equal to one so is a natural number (making the obvious inductive argument, noting that multiplication on $\mathbb{N}$ is closed), and similarly that $2 l_n - 1 \geq 2\cdot 1 - 1 = 1$ and is also a natural number, and thus the product of these two, $n$ must also be a natural number. Is it just as simple as this? I suppose my gut feeling in the proving that the map is injective would be to assume that $2^{k_n - 1} \left(2 l_n - 1 \right) = 2^{k_m - 1} \left(2 l_m - 1 \right)$ and then use the Fundamental Theorem of Arithmetic to conclude that $n = m$. Is this going along the right lines? The 'implicit' definition of the mapping has me a little confused about the approach. On a related, but separate note, I am indeed aware that if $K$ and $L$ are any countable sets, then so is $K \times L$, so trivially, taking the identity mapping we see trivially that this map is bijective and therefore that $\mathbb{N}$ is certainly countable (!), and thus so is $\mathbb{N} \times \mathbb{N}$. Hence, it's not really the statement that I'm interested in, but rather the exciting excursion into number theory that the above alternative proof provides. |
I need to get a vague idea of disk space requirements before I start forwarding logs to a Splunk instance. Each indexed line will have on average 320 characters and I will be indexing around 500,000 lines a day. My assumptions are 1 byte per character and I'm ignoring space taken by Splunk for indices, etc. That's 160MB per day. Would you say that's semi-accurate or totally off the mark? | This is a about Related: I have a question regarding capacity planning. Can the Server Fault community please help with the following: What kind of server do I need to handle some number of users? How many users can a server with some specifications handle? Will some server configuration be fast enough for my use case? I'm building a social networking site: what kind of hardware do I need? How much bandwidth do I need for some project? How much bandwidth will some number of users use in some application? |
I am supposed to find the last digit of the number $3^{459}$. Wolfram|Alpha gives me $9969099171305981944912884263593843734515811805621702621829350243852275145577745\\3002132202129141323227530694911974823395497057366360402382950449104721755086093\\572099218479513977932448616356300654729978057481366551670706\color{red}{\mathbf{7}}$ Surely there's some sort of numerical trick to doing this. I thought maybe modular arithmetic was involved? Any ideas on how to approach this problem? | I think i know how to solve it but is that the best way? Is there a better way (using number theory). What i do is: knowing that 1st power last digit: 3 2nd power last digit: 9 3rd power last digit: 7 4rh power last digit: 1 5th power last digit: 3 $3^{347} = 3^{5\cdot69+2} = (3^5)^{69} \cdot3^2 = 3\cdot3^2=3^3=27 $ so the result is $7$. |
Which badges on this site are so rare very few people have earned them? Please tell me a badge that has less than ten people who have earned it. Also please don’t tell me badges that no one ever earned and never will. Please do tell me badges that no one has earned but can earn. Thank you for helping me. | Which is the rarest badge awarded/the least popular one/the one hardest to get? |
$f$ is entire, satisfying $$|f(z)|\le \frac1{|\text{Re}(z)|}.$$ Show that $f$ is identically zero. It suffices to show boundedness. Since $f$ is bounded on the real line, then if $f$ is unbounded on the complex plane, the infinity must be an essential singularity, which means, for an arbitrarily chosen point $z_0\in\Bbb C$, we can pick a sequence $z_n$ whose moduluses tend to infinity with $f(z_n)\to z_0$, and it follows that $|z_0|\le \frac1{|\text{Re}(z_n)|}$. This is the best I can do. I'm not sure if I'm going in the correct direction. It however seems unlikely for me to deal with the problem on the $y$-strip in this way. | This is a problem from my complex analysis textbook. The hint is to consider $g(z)=(z-iR)^2(z+iR)^2 f(z)$ and to show that $|g(z)| \leq 8R^2$. This is what i have tried: Consider $Re z \geq 0$, then $|(z-iR)^2 f(z)|\leq \left(\frac{|z-iR|}{Re z}\right)^2\leq 2$ But then I don't know what to do next. Any help I'd appreciate :) |
Can I view a specific chapter in a manual? I tried man socket(2) in WSL Ubuntu 16.04 (Xenial). This is after I got a recommendation to see chapter 2 in a man of the socket utility. | I wanted to access man pages for command chmod. Command whatis chmod gave this output: chmod (2) - change permissions of a file chmod (1) - change file mode bits But I was actually looking for chmod(2). When I type man chmod, man pages for chmod(1) appears. Both man chmod(2) and man 'chmod(2)' commands show error. I tried running info coreutils 'chmod invocation', but output is some kind of documentation which doesn't look like a typical man page. |
Version confirmed with existing option: 2.82.7, Versions confirmed to omit previously existing option: 2.91.2, 2.93.0 Alpha, Steps to reproduce: Load: Factory Defaults, Select: Cube, Switch to: Edit Mode, Select: All, Left Mouse Click: Vertex (Menu drop down), Newer versions do not have the "Merge Vertices" option in the drop down menu, while key pressing "M" does still invoke the option as before. As a beginner, I always use the drop-down menu options as I slowly learn shortcut keys, as such, it is best to have as many options available in the menus. So, is this an ill-fated new feature or bug? | I downloaded the latest version of Blender 2.8 beta today. I used to remove double vertices by switching to Vertex selection mode -> Choose all vertices -> Right click > choose Remove Doubles (in Blender 2.80 which I downloaded in April). But I found the option - Remove double vertices gone. I switched to Vertex selection mode and press F3 to search but could not find it. Maybe it has got another name? |
For the last 5 months my iPhone 4S won't connect to my Windows 7 Lenovo laptop or iTunes. It will charge in 2 of my USB ports, and I've tried 3 different cables. I've tried following tips off Apple support and also from Google but still no joy. | On a Windows 8 machine, I've connected an iPhone 4s. Windows makes a audible chime for 'device connected', but doesn't allow charging in any USB port. iTunes isn't installed, and cannot be installed at this time under corporate policy. The iPhone shows as a generic device / toaster under Control Panel's Devices as below. The iPhone does NOT show as charging. Is there a driver to install to ensure the iPhone is detected and can charge via USB without installing iTunes? I've tried: forcing Windows Update |
First of all, I know it's a very bad idea to invent your own encryption algorithm. It's better to use existing known, trusted, extensively tested and studied algorithms with a proven track record. The idea below is purely theoretical, from a studying point of view. I thought of a rather simplistic encryption method, and wondering what you people think of how (in)secure this is, compared to AES. I propose the following symmetric encryption method: Given any input data, and a password (each of arbitrary length), we encrypt the data as follows: H1 and H are hashing functions (e.g. SHA256 or SHA3-512). H1 and H may be the same. n1 and n are the number of bits of H1's and H's output (e.g. if H1=SHA3-512 then n1=512, and if H=SHA256 then n=256). Preferably n1≥n. S = a randomly generated salt of 128 bits, which is written at the start of the output. K = H1(S+password) where + means binary concatenation. The data is processed in blocks of n bits (the last block may be smaller). Block i is XOR'ed with B(i) = H(K XOR i) where i is the block index (starting at zero), represented as a simple binary integer, extended to n1 bits (to match K's size). If the last block is m < n bits, only those m bits are procesed (the remaining n-m bits of the last B(i) are not used). The decryption procedure is basically the same, except S is taken from the encrypted data instead of generated. I would suggest H1 = scrypt, bcrypt, or PBKDF2 with moderate work parameters, and H = SHA256 or SHA3-256. Properties/advantages: It's a stream cipher. Every block of n bits can be encrypted and decrypted completely independent of other blocks. This makes the algorithm suitable for streaming, parallelization, and if part of the data is damaged or missing, the rest can still be decrypted (except if the salt at the beginning is corrupted). Additional data can be appended later, and parts of the existing data can be replaced in-place. Because of the random salt S, similar data encrypted with the same password will result in completely different outputs. Even if you happen to know part of the input data, nothing is revealed about the rest of the data or the password. It's fast, provided that H is fast. Encryption and decryption are the same (only difference is generating a random salt vs reading it). Other than the 128-bit salt, the encrypted data stays the same size (unlike certain other encryption algorithms, especially asymmetric). No padding involved that can be abused to tamper with the data or partial decrypting by trial and error (some other encryption schemes have padding vulnerabilities). | Generate a 256-bit random nonce. XOR it with a 256-bit reusable symmetric key. This is x. We represent numbers in simple binary instead of a counting function. 0 in dec = [256 zeros] in binary, 1 = [255 zeros]1, 23092348 = [241 zeros]1011000000101110001111100, etc. For each nth block needed for the length of the plaintext, XOR x with n and hash it with SHA-256 to form b[n]. Let p[n] be the nth 256-bit block in the plaintext and c[n] be the nth block in the ciphertext. Then c[n] := b[n] XOR p[n]. Send the unencrypted nonce along with the ciphertext. To decrypt c[n], XOR it with b[n] to retrieve p[n]. Is this secure? If so, then why do we need AES-256? If this is not secure, then is there any mode of operation for which SHA-256 is secure as a block cipher? Specifically, it would need to be used in cipher feedback, output feedback, or any other mode that only uses the cipher in the encryption direction. |
I want to convert text to an audio file containing synthesised speech that reads out that text. What free (libre+gratis) software is available for this and how do I install and use it? I don't need to use it as an accessibility tool - I just want to be able to listen back to my revision notes while doing other things, like playing games. | How to get speech output from entered text by using command-line? Also facility to change speech rate, pitch, volume etc using simple command. |
I have heard that Proxy Support in Trasmission has been removed as of version 2.12. Is it possible to use proxy by any other method? | Can anyone help me configure Transmission to download torrent files behind a proxy? I have http_proxy set in my .bashrc. |
When I use \color in the beginning of a cell in tabu, the contents of the cell are shifted downwards: The issue does not occur when there is any character in front of the \color, but a \null does not help (in fact, it increases the shift). Here is the code for the example above: \documentclass{article} \usepackage{xcolor} \usepackage{tabu} \begin{document} \begin{tabu} to 4cm {XX} Lorem & Ipsum \\ Dolor & {\color{red}Sit} Amet \end{tabu} \end{document} Why is the text shifted down, and what is the correct way to color the first word of a cell? | The following latex code prints rows one at a time. However all the cells of the rows don't come out aligned. How can I fix it. \documentclass{beamer} \usepackage{tabularx} \begin{document} \begin{frame}{} \begin{tabularx}{3.50in}{lXX} \hline & Observation & Conclusion \\ \hline \uncover<2->{1.} & \uncover<2->{Observation 1 } & \uncover<2->{Conclusion 1} \\ \uncover<3->{2.} & \uncover<3->{Observation 2} & \uncover<3->{Conclusion 2} \\ \end{tabularx} \end{frame} \end{document} The output looks as follows : As we can see cells in first column do not align with the rest of the rows. Will appreciate any input as to how to fix this. |
I've completely destroyed everything and now php wont install. I had php5.4 and everything was great. I then needed to run Magento locally which wasnt working. I saw one of the requirements was php5.3 so I downgraded using a script i found online but then PDO wasnt working. I stuffed about for a few hours following what people said online, eventually nothing was working so i purged php to do a fresh install of php5.4 to start again from scratch and figure out my problems. After i purged, i came to reinstall Php5 using apt-get install php5. Once the script ran i got the following output: Reading package lists... Done Building dependency tree Reading state information... Done Some packages could not be installed. This may mean that you have requested an impossible situation or if you are using the unstable distribution that some required packages have not yet been created or been moved out of Incoming. The following information may help to resolve the situation: The following packages have unmet dependencies: php5 : Depends: libapache2-mod-php5 (>= 5.4.9-4ubuntu2.4) but 5.3.10-1ubuntu3 is to be installed or libapache2-mod-php5filter (>= 5.4.9-4ubuntu2.4) but it is not going to be installed or php5-cgi (>= 5.4.9-4ubuntu2.4) but it is not going to be installed or php5-fpm (>= 5.4.9-4ubuntu2.4) but it is not going to be installed Depends: php5-common (>= 5.4.9-4ubuntu2.4) but 5.3.10-1ubuntu3 is to be installed E: Unable to correct problems, you have held broken packages. I then googled for ages and ran commands like clean, update, upgrade, -f install and a few others. I come back to install php and i get the same error. How can I reinstall Php so it works again. | Occasionally, when I'm installing stuff, I get an error like the following: Some packages could not be installed. This may mean that you have requested an impossible situation or if you are using the unstable distribution that some required packages have not yet been created or been moved out of Incoming. The following information may help to resolve the situation: The following packages have unmet dependencies: package1 : Depends: package2 (>= 1.8) but 1.7.5-1ubuntu1 is to be installed E: Unable to correct problems, you have held broken packages. How can I resolve this? |
I want to render an animation of a scene with multiple buildings and smaller details such that the scene will look like a miniature scale model. The concept is probably the same as for , but unfortunately my knowledge of cameras, lenses and alike is still pretty rough, so I wanted to ask if you can provide me with quick tricks and tips about how to obtain such effect in Blender. | I basically want to rotate the DoF-Plane just as a real tilt-shift lens does, so that the depth influences the blur and not a gradient. Is there a way to recreate this effect in blender? |
If $z,s\in \mathbb{C}$ ( with norm less than $1$) then show that $\left|\frac{1-s/z}{1/z-\overline{s}}\right|<1$. I'm hoping for an algebraic proof but possibly also a proof by geometric means if possible ( even with a picture if possible). | This is the question I'm stumbling with: When $|\alpha| < 1$ and $|\beta| < 1$, show that: $$\left|\cfrac{\alpha - \beta}{1-\bar{\alpha}\beta}\right| < 1$$ The chapter that contains this question contains (among others) the triangle inequalities: $$\left||z_1| - |z_2|\right| \le |z_1 + z_2| \le |z_1| + |z_2| $$ I've tried to use the triangle inequalities to increase the dividend and/or decrease the divisor: $$\left|\cfrac{\alpha - \beta}{1-\bar{\alpha}\beta}\right| < \cfrac{|\alpha| +|\beta|}{\left|1-|\bar{\alpha}\beta|\right|}$$ But it's not clear if or why that would be smaller than one. I've also tried to multiply the equation by the conjugated divisor $\cfrac{1-\alpha\bar{\beta}}{1-\alpha\bar{\beta}}$, which gives a real divisor, but the equation does not appear solvable. Any hint would be much appreciated. |
I'm following but I get an error in this paragraph : @Override public boolean onCreateOptionsMenu(Menu menu) { super.onCreateOptionsMenu(menu); MenuInflater inflater = getMenuInflater(); inflater.inflate(R.menu.main, menu); MenuItem menuItem = menu.findItem(R.id.search); SearchView searchView = (SearchView) menuItem.getActionView(); searchView.setQueryHint("Type something..."); //at this line (line 28 in the project) int searchPlateId = searchView.getContext().getResources().getIdentifier("android:id/search_plate", null, null); View searchPlate = searchView.findViewById(searchPlateId); if (searchPlate!=null) { searchPlate.setBackgroundColor(Color.DKGRAY); int searchTextId = searchPlate.getContext().getResources().getIdentifier("android:id/search_src_text", null, null); TextView searchText = (TextView) searchPlate.findViewById(searchTextId); if (searchText!=null) { searchText.setTextColor(Color.WHITE); searchText.setHintTextColor(Color.WHITE); } } return true; } I think my problem is the SearchView... I don't know what informations you need to answer... so ask me more details if you need. Logcat : 10-24 11:59:43.533 9216-9216/? E/AndroidRuntime: FATAL EXCEPTION: main 10-24 11:59:43.533 9216-9216/? E/AndroidRuntime: java.lang.NullPointerException 10-24 11:59:43.533 9216-9216/? E/AndroidRuntime: at com.drarig29.searchactionbar.MainActivity.onCreateOptionsMenu(MainActivity.java:28) 10-24 11:59:43.533 9216-9216/? E/AndroidRuntime: at android.app.Activity.onCreatePanelMenu(Activity.java:2476) 10-24 11:59:43.533 9216-9216/? E/AndroidRuntime: at android.support.v4.app.FragmentActivity.onCreatePanelMenu(FragmentActivity.java:262) 10-24 11:59:43.533 9216-9216/? E/AndroidRuntime: at android.support.v7.internal.view.WindowCallbackWrapper.onCreatePanelMenu(WindowCallbackWrapper.java:85) 10-24 11:59:43.533 9216-9216/? E/AndroidRuntime: at android.support.v7.app.AppCompatDelegateImplBase$AppCompatWindowCallbackBase.onCreatePanelMenu(AppCompatDelegateImplBase.java:241) 10-24 11:59:43.533 9216-9216/? E/AndroidRuntime: at android.support.v7.app.AppCompatDelegateImplV7.preparePanel(AppCompatDelegateImplV7.java:1247) 10-24 11:59:43.533 9216-9216/? E/AndroidRuntime: at android.support.v7.app.AppCompatDelegateImplV7.doInvalidatePanelMenu(AppCompatDelegateImplV7.java:1527) 10-24 11:59:43.533 9216-9216/? E/AndroidRuntime: at android.support.v7.app.AppCompatDelegateImplV7.access$100(AppCompatDelegateImplV7.java:90) 10-24 11:59:43.533 9216-9216/? E/AndroidRuntime: at android.support.v7.app.AppCompatDelegateImplV7$1.run(AppCompatDelegateImplV7.java:128) 10-24 11:59:43.533 9216-9216/? E/AndroidRuntime: at android.os.Handler.handleCallback(Handler.java:615) 10-24 11:59:43.533 9216-9216/? E/AndroidRuntime: at android.os.Handler.dispatchMessage(Handler.java:92) 10-24 11:59:43.533 9216-9216/? E/AndroidRuntime: at android.os.Looper.loop(Looper.java:137) 10-24 11:59:43.533 9216-9216/? E/AndroidRuntime: at android.app.ActivityThread.main(ActivityThread.java:4745) 10-24 11:59:43.533 9216-9216/? E/AndroidRuntime: at java.lang.reflect.Method.invokeNative(Native Method) 10-24 11:59:43.533 9216-9216/? E/AndroidRuntime: at java.lang.reflect.Method.invoke(Method.java:511) 10-24 11:59:43.533 9216-9216/? E/AndroidRuntime: at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:786) 10-24 11:59:43.533 9216-9216/? E/AndroidRuntime: at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553) 10-24 11:59:43.533 9216-9216/? E/AndroidRuntime: at dalvik.system.NativeStart.main(Native Method) | 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? |
public static ArrayList<Integer> getStudentClasses(Student student, ArrayList<Integer>[] classesXstudents) { ArrayList<Integer> classes = new ArrayList<Integer>(); for (int i = 0; i < classesXstudents.length; i++) { for (int j = 0; j < classesXstudents[i].size(); j++) { if (classesXstudents[i].get(j) == student.getID()) { classes.add(i+1); } } } return classes; } throws NullPointerException at the line for (int j = 0; j < classesXstudents[i].size(); j++) { which I'm assuming means classesXstudents[i].size() is null at some point. classesXstudents is an array of ArrayList objects. How should I debug this case? | 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? |
There was which was migrated to . As of current writing, the OP's username is greyed (no user profile). However, when I checked the account, they have registered both on and . This issue seems to be the same as , but it's posted 5 years ago and already got , so I doubt if this is the same case. If there's a difference, then I think it's that the user never went to Meta Android.SE before (but I can't confirm). | I'm a member of , but I'm not able to be a member of . I asked a question on here and it's migrated to Meta Gaming.SE, but I cannot handle the question because it's not considered mine. I also can't login or sign up in Meta Gaming.SE because it seems I'm already a member of it. Can anyone help me solve the problem? Previously I thought every Stack Exchange site membership means you are member of its meta too. This is from Meta Gaming.SE: But I have from here to there. |
I installed Oracle VM VirtualBox Manager on Windows 7 and I was able to run some PHP programs on it. I use Git-Bash with Vagrant to access shell (Ubuntu). I would like to try a simple Java web application on the above machine. I installed 'Nautilus' file manager and I tried to open it in the terminal by running the command: nautilus --browser (), but I get an error message as follows: (nautilus:8243): Gtk-WARNING **: cannot open display: Notes: 'X11Forwarding' is already ‘yes’ by default ($ sudo nano /etc/ssh/sshd_config). I installed all updates by running the commands: sudo apt-get update && sudo apt-get dist-upgrade My question is how to install and access files and folders on the host machine using 'Nautilus’? | The Goal: I would like to open a program from my ubuntu server in my windows 7 desktop. Steps Taken: Putty > SSH > X11 check 'enable port forwarding' I have started VNC Viewer in listening mode started putty ssh session apt get install xinit startx & geany (it's a c language ide; it uses the GUI so I"m using it to test x forwarding) Error Messages: geany returns "cannot open display" startx returns "setversion 1.4 failed" I'm working on Windows 7 and headless Ubuntu Server 12.04 LTS Obviously I forgot something, but I'm having difficulty figuring out what. The goal is to not use sudo apt get install desktop, since I only want to use one program at a time, and anyway my server isn't hooked up to a monitor. Any ideas? Questions? Thanks for your help! Curios |
Is there any configuration setting using which long running query can be killed automatically in mysql? | I would like to set a maximum execution time for sql queries like set_time_limit() in php. How can I do ? |
I had a flag on a link-only answer declined several minutes ago: not an answer – dasblinkenlight 6 mins ago declined - A link only answer is an answer - just a bad answer and should be down-voted rather than flagged. (emphasis added) According to , flagging was the right thing to do. Has this policy been changed? | Related: (not a dupe, that's a feature request and was closed as a dupe of another one) (old) post does indeed say that Link-only answers can be flagged as NAA, but there are a lot of posts like which define Not An Answer is a way that it doesn't apply to link-only answers. Can we get some up-to-date consensus on this? That link only answers are not allowed is . |
Find a closed form for $$S_n = 1 \cdot 1! + 2 \cdot 2! + \ldots + n \cdot n!.$$ for integer $n \geq 1.$ Your response should have a factorial. Another induction problem, I tried some examples but they didn't really tell me anything. | I came across this question in some extracurricular problem sets my professor gave me: what is the closed form notation for the following sum: $$S_n = 1\cdot1!+2\cdot2!+ ...+n \cdot n!$$ I tried computing some terms, and the only "vague" thing I noticed was that maybe I should be subtracting a term, but I'm really not sure. I went around looking on StackExchange's archives for a closed form of $S_n = 1!+2!+ ...+ n!$ but that didn't help me with my problem much. Any pointers? |
It's well known that X symbol means close (and in some contexts dismiss or hide), but why/where was this symbol initially chosen? My only thought was that when you want to "cancel" information on printed paper it is crossed-out and that led to X, which is similar to crossing out an item, becoming a symbol for cancel () which was then again re-purposed as close, but I have no evidence of this. Is there a history behind this symbol? | I was wondering about the reason of the choose of the X as symbol used to represents the "Close application" operation. |
I'm quite new to biblatex. I'm typesetting a collection that has papers both in English and Russian, and I'm making a single bibliography at the end of the book. For the bibliography to look pretty, the entries should be 'localized' individually. That is, I want an English book to come out as Smith and Smith (eds.) but a Russian one to come out as Иванов и Иванов (ред.) [not "eds."!] I have a very vague idea that it can be achieved with a conditional in some macro that'd check the language field of each given entry and select things accordingly. But I've no idea how to approach it --- just browsing biblatex.def lead me nowhere but here. I'm using lualatex for this, just in case. Thank you for any ideas! | According to biblatex manual (p.24), the hyphenation field in a bib-entry switches language on per-entry basis: hyphenation field The language of the bibliography entry. The identifier must be a language name known to the babel package. This information may be used to switch hyphenation patterns and localize strings in the bibliography. This functionality seemed to not work. I just used an example of bib base that comes with biblatex documentation to print the entire bibliography. \documentclass[a4paper]{article} \usepackage[T1]{fontenc} \usepackage[german,american]{babel} \usepackage{csquotes} \usepackage[style=numeric,backend=biber]{biblatex} \addbibresource{biblatex-examples.bib} \begin{document} \nocite{*} \printbibliography \end{document} The bibliography contains few entries in German. However in the printed list of references they are formatted with english strings. [8] Averroes. Drei Abhandlungen über die Conjunction des separaten Intellects mit dem Menschen. Von Averroes (Vater und Sohn), aus dem Arabischen übersetzt von Samuel Ibn Tibbon. Ed. and trans. by J. Hercz. Berlin: S. Hermann, 1869. Per-entry language switching is provided by the bundle of bst style for BibTeX. Looking through biblatex internal code, I've got an impression that biblatex needs major re-implementation in order to provide similar functionality. Or am I wrong? |
I would like to use a font similar to the one use on a Texas Instruments TI-30X calculator. Is there a font like this? | I have a code from HP 48/50G series, as shown in the image below. The closest that I did, using [lstlisting] is shown in the code snippet below. \begin{lstlisting} << SWAP DUP SIZE HEAD 1 - -> J vec N << 0 N FOR k vec k 1 + GET i NEG 2 * pi * k * J * N 1 + / EXP * NEXT N 1 + -> LIST sum LIST >> >> \end{lstlisting} Is there any way to improve it to be the same as HP screenshot? |
Basically, I've read a few threads when I had trouble getting German special characters like ü,ö,ä,ß to show up when a user uses them in a submission title. To say the least, they look like this: üöäÃ� Turns out the database collation was wrong for these types of characters (or so I've read) the collation was latin1_swedish_ci, and I've read to change it to u8_general_ci or utf8_unicode_ci. Well I've tried both but on submission to the database by a user, the title with special characters still shows up the same, all messed up like above. I guess my question is, what am I doing wrong? Is there an extra step I've missed to get these characters to show correctly? I've never worked with German translation before this particular project, and this is my first time with this. So any help would be fantastic. | 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. |
The sentence LaTeX is fun is produced by \LaTeX\ is fun Why does Latex tend to swallow the space between the words 'Latex' and 'is' unless the space is escaped by a backslash? | I have a definition: \newcommand{\arnold}{Arnold Schwarzenegger} When I refer to it by: \arnold is a it is rendered as: Arnold Schwarzeneggeris a In order to have a space in front of "is" I would need to write \arnold\ is a Is there some other shorter way? |
I want a simple thing, but I am not getting it to work Just like the browser change the confirmation text from "Are you sure you want to leave this page?" to "Are you sure you want to reload this page?" depending what you are doing, I want that my custom confirmation text also knows which action the user is performing. Currently I have this: window.onbeforeunload = function (event) { var infoText = (event.srcElement == event.target) ? "Reloading" : "Movig from"; infoText += " this page will cause you to lose current information."; return infoText; }; I thought that comparing the event.srcElement vs. event.target will be enough as they have the navigation links. But that if statement always returns true, so it always looks like it is reloading even if the destination link is different. As the browser knows, I thinks there must be some way to do it. If not, I'll have to create a generic message. (Obviously I could make it generic and... done. But now I really want to know it.) | I am currently looking at the "unload" event of a window to try to determine how the "unload" event was triggered, but am having little success. Is there a way to determine how the javascript event was triggered? Page Refresh Back Button (or navigate away from the page) Closing the Browser Essentially I need to execute some code only when the browser window is being closed, not refreshed or navigated away from. Purpose: When a customer does an update of our software, the update will redirect their first Internet request to an offer page. There is a button for a "Do Not Bother" option, but some users will simply close their browser. Upon closing the browser, I need to duplicate the "Do Not Bother" functionality so the user no longer gets redirected to the offer page. Simply attaching to the "unload" event will not work due to the different ways of leaving a page. |
Are there any performance advantages or disadvantages to using either? I notice in eclipse whenever I need to import something due to a class missing, it imports only that specific class. Understandably because that is the only class I am using at the time. For instance, I could have package.models. This models folder contains 8 classes that define the structure of data tables. This may be a small example but are there any performance advantages/disadvantages between using package.models.* compared to package.models.specific_model_name? I asked this because when I first started in my programming career I used to get slaughtered for using "select *" in my queries. I was curious if the same holds true for the importing of classes, which I have never really heard anyone mention before throughout my career. Edit: Thank you for all who responded. I unfortunately do not have enough reputation to give anyone any upvotes. I also would more lean towards this one being a duplicate, . | It is much more convenient and cleaner to use a single statement like import java.awt.*; than to import a bunch of individual classes import java.awt.Panel; import java.awt.Graphics; import java.awt.Canvas; ... What is wrong with using a wildcard in the import statement? |
From some answers regarding LastActivityDate, I know that LastActivityDate of a question considers: a) Posting a question, b) Answering a question, c) Edits to either question or answer(s) I want to know if LastActivityDate of a question from Posts.xml considers the following scenarios: a) Comment on a question, b) Comment on any answer of a question, c) Vote (upvote/downvote) to a question, d) Vote (upvote/downvote) to any answer of a question, e) Upvote to any comment on a question or any answer of a question? | What can cause a question to be "bumped" to the first page in the Active tab of a Stack Exchange site? (Changing the "Last Active" date.) . |
Following is the scenario in the picture, We have one server at back and five other servers (running 5+ applications). We are developing LDAP instead of basic Database authentication rule in which we have to set it manually. Obviously, We have different roles like: Developer, Support, Managers, Directors, etc. So, Our aim is to give permissions respectively. For example. A user who fall in developer group can edit and commit, while support person can view only. Please feel free if my concept is wrong. Technologies: Wamp Server 2.5 Apache 2.4.9 PHP 5.5 MySQL 5.6 LDAP Ubnutu v3 Following are my Questions: Does LDAP allow user permission mechanism? or I want any other third party software. In case to - NO, Do I have to make application capable to act like this? Does LDAP users/groups are linked with Linux sudoers user? in: visudo i.e. /etc/sudoers | This is a about the use of a *AMPP's stack. I recently had a talk with some experienced people and they suggested to me not to use a WAMP stack, and instead install apache, mysql and php separately. I don't understand why they have suggested this, though, so can anyone tell me? Is there a particular disadvantage of WAMP, or a particular advantage to installing all of them separately? Since a WAMP stack itself is composed of apache, mysql and php, then what's the difference between using the WAMP stack and installing them all separately? |
I want to download and verify the ISO of lubuntu. The problem is I can't find a secure channel in the first place. The official ISO is being downloaded with http (not https). Of course I can download and then verify the hash, but the only place I can find the hashes is , which is also insecure http. Any way to securely download the ISO? Edit: The proposed duplicate question is not similar to my case - it talks about downloading using apt, which uses an authentication mechanism (no user action needed). My questions is about files downloaded manually, thus I must authenticate the files by myself. | Are repository updates secure? As a bear of little brain from the developer side, I cannot understand why the repository list is http://security.ubuntu.com and the other http(unsecured) sites listed in /etc/apt/sources.list. Without a certificate chain match this appears as "ask any responder for a list of packages to update" instead of "ask the ubuntu.com site..." Can any network choose to spoof the update sites, and is this a common practice to provide a locally cached and vetted copy? |
I used Twizttid' protocol successfully (BELOW) BUT... You’ll need some Plasticine, Drano, water, GLOVES!!, a lot of paper towels and wood skewers and GOOD VENTILATION. Start the ventilation and open a window or door. Put on your gloves. Use the Plasticine to create a dam about .25″-.5″ high around the area in the oven you’re looking to remove the aluminum from. The areas you’re working in should be about 2.5″ in diameter. Pour some of the Drano into the dam and add enough water to touch all the sides of the dam. If the chemical reaction hasn’t started (should be almost instant), keep adding the Drano bit by bit until it does. The dam contents will start to boil and ammonia fumes and a little hydrogen gas will form, hence the need for some good ventilation!! Once the reaction is done, poke around with the wood skewer to see if the oven bottom is clear. If you’re satisfied with the results, add some some vinegar to help neutralize the solution a bit, then use the wood skewer to remove the Plasticine dam to a dish to be rinsed off ASAP. Use paper towels to wipe up the mess on the bottom of the oven. See your results! The area of the oven bottom you treated should be free of aluminum and just be discolored instead. Not from the Drano, but from where the Teflon bonded. Repeat the process until the oven bottom is clean. To get a ‘feel’ for the chemical reaction and what to expect, experiment first! Take a square of aluminum foil, go to the backyard with the foil shaped into a little bowl, place it on a dish or pan, add some Drano crystals to it then add a little water. Step back from the dish and try not to breath the fumes! The dish will be hot!! It took me about six hours to clean the bottom of my oven when this happened to me. AND HERE IS THE BUT... There is a mark that is identical to the aluminium shape left after the aluminium has gone. It is raised to touch and a dull black colour (looks silver in the image because of the camera flash). I do not know what it is composed of but I want to remove it. Does anybody know how? (P.s. This is a new oven and I'm not going to scrape it off even if it will come - not my oven). | I had this brilliant idea to put aluminum foil at the bottom of my oven while I cooked pizza at very high temperatures. I was hoping it would catch any toppings that fell off so I could quickly remove them and prevent smoke. The result is that the foil bonded to the oven and now I'm not sure how to get it off. Any chemicals or tools I should use in this situation? |
Suppose $S$ is a finite set with a binary operation $*$ given by a Cayley table. While the commutativity of $*$ can be determined on the basis of the symmetry of the table across the upper-left to lower-right diagonal, is there any way we can, by inspecting the table alone, decide if $*$ is associative or not? | Most properties of a single binary operation can be easily read of from the operation's table. For example, given $$\begin{array}{c|ccccc} \cdot & a & b & c & d & e\\\hline a & e & d & b & a & c\\ b & d & c & e & b & a\\ c & b & e & a & c & d\\ d & a & b & c & d & e\\ e & c & a & d & e & b \end{array}$$ it is easy to check that it is closed (no elements occur in the table which don't occur as row or column index), commutative (the table is symmetric), has a neutral element (the row and column of $d$ are copies of the index row/column), and has an inverse element for each element (there's a $d$ in each row and column). In other words, almost all important properties can immediately be seen. The only part missing is associativity. Therefore my question: Is there a simple way to see directly from the operation's table (i.e. without doing explicitly all the calculations) if an operation is associative? |
I'm running Ubuntu 16.04 and Windows 10 on 2 separate hard drives (no partitions, 2 physical hard drives). Two things have happened: I no longer get the GRUB boot loader screen which allows me to choose which operating system I boot into (I recall that this used to work under a similar setting running Linux Mint 15 and Windows 7) Suddenly Windows 10 won't boot anymore. Even though I set it as the first drive to boot from in the BIOS. What am I doing wrong here? I've seen some stuff about installing ubuntu in uefi mode. Is that something I need to consider? I am fairly new to Ubuntu and a complete noob when it comes to setting up partitions, etc. Thank you, BR Johan | Accidental BIOS mode install I have Intel 64-bit hardware with UEFI setup utility. Ubuntu 14.04.1 LTS was installed as the only operating system on the only drive attached. Accidentally Ubuntu was installed in BIOS/CSM/legacy mode. Convert to UEFI While later on learning about UEFI, the goal is to change this existing Ubuntu installation to (quicker) boot via EFI/UEFI. I do still want to have some kind of - 2 seconds displayed - boot menu that allows me to enter the UEFI setup utility. Therefore I think I do need use Grub (can't use an EFI boot stub) and . I have already re-partitioned the drive using a Live CD and inserted a 200 MiB EFI partition in the beginning of the drive and marked that fat16 formatted partition as type id 0xEF. Before: # fdisk -l /dev/sda ... Device Boot Start End Blocks Id System /dev/sda1 * 2048 108478463 54238208 83 Linux /dev/sda2 108480510 125044735 8282113 5 Extended /dev/sda5 108480512 125044735 8282112 82 Linux swap / Solaris After: Device Boot Start End Blocks Id System /dev/sda1 * 411648 108478463 54033408 83 Linux /dev/sda2 108480510 125044735 8282113 5 Extended /dev/sda3 2048 411647 204800 ef EFI (FAT-12/16/32) /dev/sda5 108480512 125044735 8282112 82 Linux swap / Solaris Partition table entries are not in disk order No boot-repair please The Ubuntu community wiki suggests to use boot-repair to . I don't want to use a GUI, or install any extra packages, and I don't want any data being accidentally sent to pastebin.com and because I do want to know what will be changed exactly, I don't want to use . Under the hood Trying to figure out what boot-repair actually does, I found this snippet: Boot-Repair will convert a BIOS install to UEFI by uninstalling grub-pc, and installing grub-efi, if gpt partitioned. source: UEFI mode install comparison A clean Ubuntu 14.04.1 installation in UEFI mode creates a 512 MiB Fat32 formatted EFI partition. That partition contains one directory /EFI/ubuntu, containing 4 files: grub.cfg, grubx64.efi, MokManager.efi and shimx64.efi. The grub.cfg contains: search.fs_uuid 7d843e47-3917-4114-8725-55dfa1fbe002 root hd0,gpt2 set prefix=($root)'/boot/grub' configfile $prefix/grub.cfg Search.fs_uuid points to the UUID of the Linux installation partition, in this comparison UEFI installation Linux is installed partition /dev/sda2 (versus sda1 in BIOS mode installation). No potential Asrock firmware issues found Having CSM still disabled in firmware and using the clean UEFI mode Ubuntu installation. Resizing the 512 MiB EFI partition to 200 MiB using a Live CD and gparted results in that its formatting changes from FAT32 to FAT16. The Asrock firmware P1.50 (incorrectly called BIOS by AMI in boot message "BIOS date") is still able to boot into UEFI mode Ubuntu: UEFI+FAT16 = ok. (msdos) using the same Live CD terminal command gdisk and its commands r g p w also results in a UEFI bootable Ubuntu on an MBR partitioned drive: UEFI+MBR = ok. Question Does this mean that the only commands I do need to execute - from the legacy Ubuntu install and in this order - are: # apt-get install grub-efi # apt-get remove grub-pc ? Or is more needed to be done? |
I cannot download anything or upgrade my system. I get the following error message: dpkg: file triggers record mentions illegal package name `doc-base/noawait' (for interest in file `/usr/share/doc-base'): character `/' not allowed (only letters, digits and characters `-+._') E: Sub-process /usr/bin/dpkg returned an error code (2) I also cannot use USB creator to do fresh install as my system fails to load bootloaders. Please help | I'm doing an upgrade with sudo apt-get upgrade After I press Enter: do you want to continue [y/n]? y debconf: apt-extracttemplates failed:No such file or directory extracting templates from package: 100% dpkg:error:parsing file '/var/lib/dpkg/status' near line 1146 package 'python-minimal' 'break' field, invalid package name 'python-de~': Character '~' not allowed (only letters,digits and character '-+._') E:Sub-process /usr/bin/dpkg returned an error code (2) How to fix or edit this??? |
I have some queries which clip rasters from polygon. So how I can see my result query in postgis or How I can check my query true or false ? | Reading the solution to got me thinking. How can I graphically display a SQL query? It doesn't need to be cartographic quality. A sketch for debugging purposes would be sufficient. For example, this SQL is in the accepted solution: SELECT ST_Touches(temp.point1, temp.point2) as geom_touches , ST_Intersects(temp.point1, temp.point2) as geom_intersect FROM ( SELECT * FROM ST_Buffer(ST_Transform(ST_GeomFromText('POINT(-105.05083 39.74823)', 4326), 2877), 1500) as point1 , ST_Buffer(ST_Transform(ST_GeomFromText('POINT(-105.04428 39.74779)', 4326), 2877), 1500) as point2 )as temp How could I draw ST_Touches() and ST_Intersects() - the geometry, not the boolean? |
I'm asking this question because I was taught not to use double negatives, because they are ungrammatical and that people who use them sound uneducated. However, today here on this site I found an answer with a double negative and asked my self is it correct to use double negatives? Well my doubts arose since this answer has eight positive votes. Even though I understand the meaning of it, I still wonder if it is correct or not. Below is the answer I'm talking about as well is the link to it. Answer: "It might add the subtle extra nuance of meaning that since you were born he's never not been in the family." Link: P.S. Not trying to put this site and the people from it in doubt, just clarifying and making sure to learn well this beautiful language. | In my native language, double negations "cancel out". I have been trying to learn English using movies and such things, but double negation confuses me. I see instances when double negation cancels out, and some when they do not. For example, "I haven't got no money" is interpreted as "I have no money." "There wasn't anyone who didn't enjoy the party" is interpreted as "Everyone enjoyed the party." Is this context dependent? If so, how does one decide which interpretation is correct? |
Here's what I have: cat UserReport.txt | mail -s "TestSubject" "[email protected]" It's a small file, much smaller than a picture so it should send almost instantly. Though I receive nothing. I installed mailutils but might have installed it incorrectly. How can I send an email from a bash script? | How to send mail from the command line? |
Let $q$ be an element of $\mathbb{Q}$ (rational numbers). How can I prove that $\sin (2\pi q)$ is algebraic over $\mathbb{Q}$ for any $q$? I am trying the method: Euler formula: $e^{i\theta} =\cos \theta+i\sin \theta$ so $2\sin\theta = ie^{i\theta}-ie^{-i\theta}$. $i$ is root of $x^2+1$. So if I prove that $e^{i\theta}$ and $e^{-i\theta}$ is algebraic over $\mathbb{Q}$f or $\theta=2\pi q$, it will be ok. | Here $p$ and $q$ are co-prime integers. Is it necessarily an algebraic number? |
I'm trying to figure out how to just get unanswered questions by a tag in the Stack Overflow app. Is it possible right now? If not can anyone give an ETA on when this is coming out? | It seems that if I want to see unanswered questions, I can only list all unanswered questions, or unanswered questions with a specific tag. If I try to use the search box in the top-right, it always seems to search ALL questions. It would be more than useful to be able to search unanswered questions only. |
Currently I have Ubuntu 14.04 LTS installed on my PC, but unfortunately there are some programs, which do not run on Ubuntu even with Wine and there are no good alternatives available. Therefore I want to additionally install Windows now. This [ article and many others recommend to first install Windows and then Ubuntu, an option that I do not have unless I can somehow back-up and transfer this current system. It speaks of some advantages to virtualizing the other OS, but due to lack of knowledge, I do not really know what that means and what would be the best option in my case. I plan to use Ubuntu 95% of the time and Windows only for few programs, that don't run on Ubuntu. What do you recommend and how do I go about it? Best regards and thanks for any advice! Markus | I installed Windows 7, which ate Ubuntu's boot file. When starting up the computer, it now goes straight to Windows, without giving me the option of booting Ubuntu. How can I get Ubuntu back? |
I want to create a citation like: [15, Eq.(3.27)] Do you know how can I do it using \cite? | I would like to cite the item (iii) of proposition 3 of a reference. How can I do it? Which ways do you suggest? This is a question not only about LaTeX, but also about style. One option I have seen to cite pages of a reference is \cite[p.~333]{Audet}. Is there something similar to cite theorems, propositions and so on? |
I cannot remember much about this novel (series of novels?) but: The earth is overpopulated. Everyone has to go into suspended animation, and we all take turns living, I think one quarter of humanity for a day at a time. At the end of the 24 hours, that group goes back into the chambers, and the next group comes out. The groups' realities do not intersect and they experience completely separate lives in different societies. As you can expect, some people decide to live continuously, in effect living two lives. So, what's it called? | This story is about a man that is able to live every day of the week, while everybody else has a single day of wakefulness assigned to them. Due to overpopulation, each human spends 6 out of 7 days of the week in stasis, and has jobs assigned to them in daily shifts. 1/7 of the population works on Monday. 1/7 works on Tuesday, & so on. The main character has found away to circumvent the process and illegally live out his days consecutively by skipping the stasis program that is imposed on the general population and by working a different job everyday. Can somebody name this scifi story? |
I'm quite new to blender and I cant find a way or the option to change the principal axis of a project i.e. from Z axis pointing up I want the Y axis to point up in such a way that the Z axis signifies depth in the scene. I am trying to change this due to the need to see how I will be able to debug the renders that I am doing through code. I would appreciate if anybody would guide me though this. | After learning bits and pieces of Maya, 3DS Max, IMAGINE and XSI I noticed that they all have Y-up worlds with Z being used for depth (naturally). is there a way to make Blender a Y-up world? and does anyone know why isnt it Y-up in the first place? |
I have this method: private ArrayList<Image> imageArray(File files[]) { ArrayList<Image> images = null; for(int x = 0; files.length > x; x++) { //I want to add each PNG-File to the Image-Array try { images.add(x, ImageIO.read(files[x])); //Demo.imageArray(Demo.java:23) }catch(IOException | ArrayIndexOutOfBoundsException exception) { exception.printStackTrace(); } //Now I scale each Image, so it fits the screenSize int newWidth = (int) screenSize.getWidth(), newHeight = newWidth * images.get(x).getHeight(null) / images.get(x).getWidth(null); if(newHeight > screenSize.getHeight()) { newHeight = (int) screenSize.getHeight(); newWidth = newHeight * images.get(x).getWidth(null) / images.get(x).getHeight(null); } images.set(x, images.get(x).getScaledInstance(newWidth, newHeight, Image.SCALE_SMOOTH)); } return images; } which causes this Exception : Exception in thread "main" java.lang.NullPointerException at Demo.imageArray(Demo.java:23) //I've marked the position in the code! at Demo.main(Demo.java:47) // Just, when I want to use the method anywhere Why do I get that Error and how can I work around it? I have added a parameter, when I wanted to use the method, which looks like this : imageArray(new File[] {new File("filePath to PNG-Image"), new File("filePath to PNG-Image")}) | 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? |
\documentclass{article} \usepackage[landscape,a4paper]{geometry} \usepackage{array,booktabs} \usepackage{amsmath} \usepackage{background} \usepackage{xcolor} \usepackage{fancyhdr} \pagestyle{fancy} \lhead{header1} \rhead{header2} \begin{document} Some text \end{document} in the center of page "DRAFT" appears, how can i erease it? it will appear when i use fancyhdr , but there is no code about it i think =\ | I installed background package and there is text "Draft" all the page How can I remove this text or uninstall this package? |
how would i go about sub-surfing this and keeps its sharp edges? more specifically i am having difficulty with subdividing the the plate like objects on its upper arms and thighs,i have tried the usual methods such as moving edge loops and adding creases but they all leave some kind unsightly deformity, especially when combined with the solidify modifier. most of the other parts of this model such as its torso and head subdivide without issue. just what am i doing wrong and how do i make its arm and leg plates smooth with deforming or losing definition? this was marked as duplicate and linked to a question which told me to use supporting loops and creases which as i already stated doesn't work. | How can I use the subdivision surface modifier to create more high poly meshes without ruining sharp edges? For example this mesh The sphere should be subdivided but the rim of the cylinder should stay the same because it is a sharp edge. This is the result of the subdevision How can I get sharp edges to not be affected by the sub surf mod? |
Suppose $X_1, X_2 ...X_n$ are non-correlated and Gaussian random variables, all with mean value $\mu=0$ and variance=$\sigma$. Is there an expression for the distribution of $Z=\max(X_1, X_2, ... X_n)$? If not, can we find its expected value $\textrm{mean(Z)}$ and $\textrm{variance(Z)}$? Thanks a lot! | Is there an exact or good approximate expression for the expectation, variance or other moments of the maximum of $n$ independent, identically distributed gaussian random variables where $n$ is large? If $F$ is the cumulative distribution function for a standard gaussian and $f$ is the probability density function, then the CDF for the maximum is (from the study of order statistics) given by $$F_{\rm max}(x) = F(x)^n$$ and the PDF is $$f_{\rm max}(x) = n F(x)^{n-1} f(x)$$ so it's certainly possible to write down integrals which evaluate to the expectation and other moments, but it's not pretty. My intuition tells me that the expectation of the maximum would be proportional to $\log n$, although I don't see how to go about proving this. |
given three distinct lines $g,h,l$ meeting in one point $P$. I want to construct a triangle with vertices on $g,h,l$ such that those lines $g,h,l$ become its angle bisectors. In general, if we consider a triangle $\Delta(ABC)$ with angles $\alpha,\beta,\gamma$ whose angle bisectors meet at a point $P$, then I recognized the following relations between the angles: $$\angle (APB)=\frac{1}{2}(\pi+\gamma), \angle (BPC)=\frac{1}{2}(\pi+\alpha), \angle (CPA)=\frac{1}{2}(\pi+\beta).$$ Now suppose we choose points $C,C'\in g$ on different sides of $g$ with respect to $P$ and let $Q\in l,R\in h$ such that $C'$ lies in the interior of the angle $\angle (QPR)$. I started the construction as follows: Construct the angle $\angle (QPR)-\pi/2$ on one side of $g$ at the point C. Then we get a intersection point $A$ with the ray $\overrightarrow{PQ}$. Construct the angle $\angle (QPR)-\pi/2$ on the other side of $g$ at the point C. Then we get a intersection point $B$ with the ray $\overrightarrow{PR}$. Now connect the points $A,B$ But now I'm worried about the angles at $A,B$. I do not know if the angles have the right size and the lines $l,h$ through $A,B$ are indeed angle bisectors? Maybe my construction is wrong. Do you know how to do it right? Best wishes | given three lines $\ell_1,\ell_2, \ell_3 $ which intersect in one point $P$. How can one construct a triangle such that the given lines become its angle bisectors? So far I tried to find conditions on how the three given lines have to intersect such that the desired triangle exists. There are altogether six rays $\omega_1^1, \omega_1^2; \omega_2^1,\omega_2^2;\omega_3^1,\omega_3^2$ - any line $\ell_j$ determines the two rays $\omega_j^1,\omega_j^2$- emanating from the common point $P$. Any of the three vertices $V_1,V_2,V_3$ of the desired triangle has to lie on exactly one line, i.e. $V_j\in \ell_j=\omega_j^1\cup \omega_j^2$. Hence we have either $V_j\in \omega_j^1$ or $V_j\in \omega_j^2$. Therefore the triangle should exist if and only if it is possible to choose three rays $\tilde{\omega}_1\in \lbrace \omega_1^1, \omega_1^2\rbrace $, $\tilde{\omega}_2\in \lbrace \omega_1^2, \omega_1^2\rbrace$, $\tilde{\omega}_3\in \lbrace \omega_1^3, \omega_1^3\rbrace$ such that any three of the rays $\tilde{\omega_1}, \tilde{\omega_2}, \tilde{\omega_3}$ form an angle less than $\pi$. But I do not know how to construct the triangle?! I started to draw a circle around $P$ with any radius. Now I can choose a Point $V_1$ on the ray $\tilde{\omega_1}$ outside the circle. And now I can draw the tangents through $V_1$ to the circle. I think those tangents will meet the other rays at some points $V_2,V_3$ (Why?). Now we can draw the line $V_2,V_3$. But this line needs to be tangent to the circle and I'm not sure about that. Will this construction work, or is it done in a different way? Best regards |
My question is about how dangerous a momentary amount of current is vs the duration. Like is there a reasonably consistent relationship between current duration through the body and relative danger? I.e. 1 amp for 1 second vs 0.01 amps for 100 seconds. I imagine that's a bit complex to determine, but otherwise is there a duration for which a normally deadly amperage would shock someone but not cause a heart attack? I read an article about research into a possible electric weapon that would shock someone on the scale of nanoseconds to stun them without risking killing them. | I have a few circumstances which invlove someone being shocked with 20 watts of electricity and whether it would be deadly. So here they are: Would 1000 volts at 20 miliamperes of AC (2MHz frequency) be dangerous or deadly? Would 1000 volts at 20 miliamperes of DC be dangerous or deadly? Would 10 Kilo volts at 2 miliamperes of AC (2MHz frequency) be dangerous or deadly? and Would 10 Kilo volts at 2 miliamperes of DC be dangerous or deadly? Thanks for everyones help. |
I need to delete user from a mySQL row. My "Delete" button works only on the first page, but when I change page it no longer works, . This is the code I use for delete: $(document).ready(function() { $('#large').dataTable({ "sPaginationType": "full_numbers", "iDisplayLength": 5, "aoColumnDefs": [{ "bSortable": false, "aTargets": [-1] }] }); $(".lnk").click(function() { if (confirm("This user will be deleted. Press ok to confirm.")) { $.ajax({ type: "POST", url: "deactivate-user.php", data: { "user": $(this).attr('id') }, dataType: 'HTML', success: function(data) { if (data == "Error") { $("#msg").html("Error occured while removing user! Please try after some time."); $("#msg").addClass("red-box"); $("#msg").css("display", "block"); } else { $("#msg").html("User has been removed successfully."); $("#msg").addClass("green-box"); $("#msg").css("display", "block"); $("#main-table").html(data); } } }); } }); }); <td> <a href="add-credit.php?user=<?php echo $row['user_id']; ?>" name="credit" class="btn btn-primary credit">Credit</a> <a id="<?php echo $row['user_id']; ?>" class="btn btn-danger lnk">Delete</a> </td> Where is my error? | I have a bit of code where I am looping through all the select boxes on a page and binding a .hover event to them to do a bit of twiddling with their width on mouse on/off. This happens on page ready and works just fine. The problem I have is that any select boxes I add via Ajax or DOM after the initial loop won't have the event bound. I have found this plugin (), but before I add another 5k to my pages with a plugin, I want to see if anyone knows a way to do this, either with jQuery directly or by another option. |
If I have values in cell A2=2,4,8,6,12,19,18,23,35,78,101,38,30,205,2 And I want to sort by smallest to largest or largest to smallest in cell B2. then my desired result should be =2,2,4,6,8,12,19,18,23,30,35,38,78,101,101,205 or,Large to small= 205,101,101,78,38,35,30,23,18,19,12,8,6,4,2,2 if I have textvaluse like in A3= WPN/01,AFF/02,PROP/4,ENG/03 Then I want to sort alphabetically my desired result should be in cell B3=AFF/02,ENG/03,PROP/4,WPN/1 | I'm looking for a decent sort implementation for arrays in VBA. A Quicksort would be preferred. Or any other other than bubble or merge would suffice. Please note that this is to work with MS Project 2003, so should avoid any of the Excel native functions and anything .net related. |
Let $f:[0,1]\rightarrow\mathbb{R}$ be a continuous function and let $\{a_n\}_n$ and $\{b_n\}_n$ be sequences of real numbers such that: $$\lim_{n\to\infty}\int_0^1|f(x)-a_nx-b_n|\text{dx}=0$$ Prove that: a$)$ The sequences $\{a_n\}_n$ and $\{b_n\}_n$ are convergent b$)$ The function $f$ is linear In this particular problem which was given in an entrance examination of $10+2$ level,my approach was to do the epsilon delta definition of limit with integration ,but of no avail. I cannot start and arrive at the result... Kindly help anyone. | Let $f:[0,1] \to \mathbb R$ be a continuous function and the sequences $(a_n)_n,(b_n)_n$ s.t. $$\lim_{n\to \infty} \int_0^1 |f(x)-a_nx-b_n| dx=0.$$ Prove that $(a_n)_n,(b_n)_n$ are convergent. I know that $$\left|\int_0^1f(x)dx\right| \le \int_0^1|f(x)|dx.$$ Can somebody help me, please? |
Let $X = \mathbb{R}$ and $Y = \left \{ x \in \mathbb{R}\mid x ≥ 1 \right \}$. Define $G : X → Y$ by $G(x) = e^{x^2}$. Prove that $G$ is onto. | Let $X = \mathbb{R}$ and $Y = \{x \in \mathbb{R} :x ≥ 1\}$, and define $G : X → Y$ by $$G(x) = e^{x^2}.$$ Prove that $G$ is onto. Is this going along the right path and if so how do get the function to equal $y$? $G: \mathbb{R} \to\mathbb{N}_1$. Let $y$$\in $$\mathbb{N_1}$. claim: $\sqrt{\ln y}$ maps to $y$. Does $\sqrt{\ln y}$ belong to $\mathbb{N_1}$? Yes because $y \in \mathbb{N_1}$, $G( \sqrt{\ln y})=e^{(\sqrt{\ln y})^2}$. |
My imported text contains several Unicode escape sequences \u0092 \u0093 \u0094 \u0095 \u0096 Sample text: string str = " Canadian Equity Funds may also invest in or use derivative instruments as described in “Investment Strategies – Use of Derivative Instruments" "; Example c# text: may also invest in or use derivative instruments as described in \u0093Investment Strategies \u0096 Use of Derivative Instruments\u0094." I tried using this Regex rx = new Regex(@"\\[uU]([0-9A-F]{4})"); var newString = rx.Replace(input, match => ((char)Int32.Parse(match.Value.Substring(2), NumberStyles.HexNumber)).ToString()); I get exactly the same string. I tried about every way I could to convert these to actual text, but to no avail. What am I supposed to do with them? | Say you've loaded a text file into a string, and you'd like to convert all Unicode escapes into actual Unicode characters inside of the string. Example: "The following is the top half of an integral character in Unicode '\u2320', and this is the lower half '\U2321'." |
I recently discovered this fellow in my Grimoire Has he made an appearance in the game yet? I haven't come across this individual yet, so is his appearance triggered by story events? The says Xûr sells extremely rare goods in exchange for Strange Coins and only appears on weekends. Xûr's coming and going depends on the planetary alignments. This seems inconsistent, does he appear every weekend or just when he (Bungie) feel like it? | I found this Xur Agent of the Nine guy in the corner of the Tower near the Crucible Quartermaster a few days ago but he disappeared soon after. He had lots of exotic (rare) items that looked scrumptious. I've read online that he shows up on weekends, but I don't see him there now. Is he only in certain Towers? What are his spawn conditions? |
Party members Alex, Bart, and Caroline are in combat with a Drow, in that turn order (A, B, C, D). Alex uses the help action on the Drow, being within 5ft. If Bart chooses not to attack on her turn, can Caroline attack with advantage because of Help? If Bart decided to attack, would Bart have gotten advantage instead? Does a specific ally need to be named to benefit from the advantage? Or is it first-to-attack? | I am aware that usually one has to specify who is to benefit from one's Help action. However, when it comes to using it in combat, by Jeremy Crawford says: If you use the attack-aiding option in Help, the next ally who attacks the target gets the benefit. However, maybe one wants to help a specific ally (e.g. enable a rogue to Sneak Attack) but initiative puts them much later in the round. Still, for some other tactical reasons, it might make next to no sense for the remaining allies to avoid attacking that target in the meantime. Of course, one could argue that, as long as you can describe reasonably how you provide help to exactly that one specific ally without influencing the rest of the fight, something like this should be allowed. But I wonder if there is any explicit mention of this in the rules. I've been referred to this extremely similar question: My main point of interest is the issue that is raised in and the comments below it. Since this discussion is about a year old, maybe the remaining unclarities could be solved by more recent publisher's comments? Thanks a lot for your help! (Horrible pun not intended.) |
I used a graph package coinor.gimpy to implement some algorithms in network theory. And I want to use the graph class as one input of a function, however, I want to check whether this variable is this class or not, I don't know how to do, following are some of the code. from coinor.gimpy import Graph g=Graph() print type(g) and the result is <class 'coinor.gimpy.graph.Graph'> Then inside one function, the code might be like the following, def Dijkstra(g) if type(g) == ?? then ... my question is: what should I write to replace the question mark? Thanks. | What is the best way to check whether a given object is of a given type? How about checking whether the object inherits from a given type? Let's say I have an object o. How do I check whether it's a str? |
Why do we write "The shop is open" and not "The shop is opened"? The passive voice is formed this way: verb + ed. On the other hand, we write "The shop is closed". | Is there are rule when to use opened vs open? I always get confused even though I've been speaking English as the dominant language for more than half my life. E.g. Is the door open(ed)? Which file do you have open(ed) in your editor? |
I am trying to make a bot clear an interval if my config file says "off" but leave it running if it says "on". I've already tried doing discord.js config.Interval = setInterval(() => { WallCheck.send(WallCheckembed); }, 500); clearInterval(off) }; but when I put in the "config.Interval" its setting the setInterval to "config.Interval". discord.js config.Interval = setInterval(() => { WallCheck.send(WallCheckembed); }, 500); This is my code. And my config file is: "Interval": "off" The only error I'm getting is this: (node:6844) UnhandledPromiseRejectionWarning: ReferenceError: off is not defined And the variable "off" is referring to the "off" in my clear interval. | I am using setInterval(fname, 10000); to call a function every 10 seconds in JavaScript. Is it possible to stop calling it on some event? I want the user to be able to stop the repeated refresh of data. |
I have a question regarding assembly/file versioning in Class Library project in Visual Studio (C#). We have 4 numbers (example: 1.0.0.0) and according to: The four numbers are in this format: [major version].[minor version].[build number].[revision] My question is, how exactly do we determine "Major", "Minor", "Build Number", and "Revision"? Are "Major" and "Minor" more subjective while "Build Number" and "Revision" more objective (as we can actually count them)? Are there any actual "rules" regarding that? I am rather confused because according to this thread: basically it is a matter of preference. Can anybody clarify or having proper "rules" (with example will be best) regarding this? | My company is building a product. It's going to be versioned by SVN. It's a webapp so basically there will never be a version out which doesn't have some features in them and thus could always be labeled as beta. But since it's going to be a corporate product I really don't want the "unstable watchout" on there. So how would you go about versioning? Is 1.0 stable? Should the build date be in the version number? Tell me what you guys think! |
My teacher was explaining how sometimes a comma isn't enough to make a sentence correct, and that sometimes you have to use a semicolon. I am having trouble figuring out when you should use which. Can someone please explain? | Is this sentence acceptable? You’re welcome, have a nice day ahead. |
I rendered my scene with 1000 samples and it is still looking grainy. I would like to pass another 1000 samples on top of this render result. When I start a new render Blender starts rendering the new image. Is it possible to tell Blender to reuse the result of the previous render and just run another set of samples on top of it? | I am rendering my scene with only one sample but all the renders of the same picture have a different seed value. How can I combine them correctly? I wrote a java-program that loads all the images and takes the average pixel color for each pixel of the images. Is that a correct way of combining the images? It doesn't reduce the noise very much so I am not happy with it. What can I do? |
I have a Linux server, where when I connect by PuTTY, I first need to log in using a non-root account (let's say user1), and then issue the command su root or su - root to log in to the root account. I cannot log in directly to the root account as such direct access is blocked for security reasons. I would like to know how such a setup can be achieved in WinSCP, a GUI file manager for Unix/Linux servers. I have tried tunnelling to the same IP address but this does not work as I believe this attempts a "direct" login to the root account through the tunnel connection established using user1 account. Setting Shell to sudo su - also does not work. How do I get WinSCP to emulate the su root or su - root indirect login as it can be done in PuTTY? | I'm using WinSCP to access Unix computers. How can I change user after I have logged into a Unix server using WinSCP? E.g. I have personal account in Unix computer A. I can log into this computer using PuTTY and then change user to root user $sudo /usr/bin/su - rootuser How can I do the same thing using WinSCP? I don't know the password for rootuser. |
I've seen other related questions concerning this issue, but I can't figure it out. QGIS doesn't show me Google Layers from the OpenLayers Plugin, and the following message comes out: This page was unable to display a Google Maps element. Please contact the site administrator. If you are the administrator of this site, please check the JavaScript console or check the following page for troubleshooting: My knowledge on QGIS is pretty basic. | Whenever I try to load the Google Hybrid layer on QGIS 1.8.0 and 2.0.1, I get this error: This page was unable to display a Google Maps element. Please contact the site administrator. If you are the administrator of this site, please check the JavaScript console or check the following page for troubleshooting: How do I correct the error so that the map can load? |
The sample standard deviation and standard error of the mean are biased estimators for their corresponding population population parameters. As explained for the sample standard deviation this is due to the fact that the expectation of a square root does not equal the square root of an expectation, as can be shown by Jensens equality. Nevertheless, we are inclined to give an interpretation to standard error estimates, in the sence that they give the mean distance of all sample estimators (means) to the population parameter (mean). However, this seems only to be legitimate if the bias is commonly small or vanishes in large samples under quite general conditions (e.g., distributions). In the proof references above, this seems to be the case for normal data. Is this generally so? Furthermore: the sample standard error is commonly used as estimator of population standard error in a t-statistic. $$t=\frac{\hat{\theta}-\theta}{s.e.({\hat{\theta}})}$$. Is it true that we would actually need an unbiased estimator of the standard error in this formula or is the use of a biased estimator allowed. What is the role of the sample size again (for normal / non-normal data)? | I was reading on the computation of the unbiased estimation of standard deviation and the source I read stated (...) except in some important situations, the task has little relevance to applications of statistics since its need is avoided by standard procedures, such as the use of significance tests and confidence intervals, or by using Bayesian analysis. I was wondering if anyone could elucidate the reasoning behind this statement, for example doesn't the confidence interval use the standard deviation as part of the calculation? Therefore, wouldn't the confidence intervals be affected by a biased standard deviation? EDIT: Thanks for the answers so far, but I'm not quite sure I follow some of the reasoning for them so I'll add a very simple example. The point is that if the source is correct, then then something is wrong from my conclusion to the example and I would like someone to point how how the p-value doesn't depend on the standard deviation. Suppose a researcher wished to test whether the mean score of fifth graders on a test in his or her city differed from the national mean of 76 with a significance level of 0.05. The researcher randomly sampled the scores of 20 students. The sample mean was 80.85 with a sample standard deviation of 8.87. This means: t = (80.85-76)/(8.87/sqrt(20)) = 2.44. A t-table is then used to calculate that the two-tailed probability value of a t of 2.44 with 19 df is 0.025. This is below our significance level of 0.05 so we reject the null hypothesis. So in this example, wouldn't the p-value (and maybe your conclusion) change depending on how you estimated your sample standard deviation? |
What's correct? Petrovski's home/residence or Petrovski home/residence. Note that Petrovski is the family name (last name), not the first name. I know that for first name is always 's, but what about family name? | I know the former is the generally accepted usage, as that’s all I’ve ever seen over the years; meaning, by extension, "The Smiths ..live here" – presumably; whilst the second example implies, "The Smiths’ Home", which seems to me an obviously superior proposition for a sign on a residence. My bias makes me suspect the former is just a pragmatic simplification that has become standard practice (but then, so is the latter an incomplete shortcut.) What might a pedantic English instructor think if driving by such a sign, The Smiths’, and why? |
I am viewing a Stack Exchange question in Chrome on a Windows machine. If I now click on "Print...", I obtain the following preview: Visually, there appears to be way too much white space to the right of the question, and this continues down through the comments and answers of this question. In this format, just this single question and a few short comments and answers require seven pages to print. Multiple other meta.se questions have noted this margin issue (see , , , and possibly for examples), and the fix seems plausibly trivial (possibly just changing several widths to "auto" in the relevant CSS). So my question is, what hope do we have that this may be corrected in the near future? P.S. For interested users, there are great SE-developed tools to download SE content. See for a description of these. I see these as complementary to, not a replacement for, well-formatted printing directly from the primary landing page. | So I have to print some Stack Overflow pages and bring them around. Just accept it. Problem: while pages may look perfectly normal on the web, something recently broke the print layout... a huge whitespace block showed up on the right (, ). Tons of whitespace. This is on every site on the network () on a bunch of different screens (). Futzing with DevTools, the problem seems to be : #mainbar, .mainbar { width: calc(100% - 300px - 24px); } Can someone check if this is the only issue and possibly fix this? |
Some people are telling me the day after tomorrow is "this Saturday", and "next Saturday" is a week later. To others, "this Saturday" is synonymous with "next Saturday". A few people claim that "this Saturday" is synonymous with "last Saturday", but I am reasonably certain those people are nuts. | At what point does next Tuesday mean the next Tuesday that will come to pass and no longer the Tuesday after the Tuesday that will come to pass? And, when does the meaning switch back? |
He started working for this factory a year ago. Which sentence has the same meaning? He has been working for this factory for a year. or He has worked for this factory for a year. | Non-native speakers often get confused about what the various tenses and aspects mean in English. With input from some of the folk here I've put together a diagram that I hope will provide some clarity on the matter. I offer it as the first answer to this question. Consider it a living document. Input is welcome, and good suggestions will be incorporated into the diagram. Nota bene: What this is not is a discussion of whether there are more than two tenses in English. , to which this question is not intended to supply arguments one way or the other. Here, the aim is to provide an overview of what constructions English-speaking people use for conveying information about actions referring to past, present, and future, and to provide it first and foremost to precisely the people who are likely to use "tense" as a catch-all term in their search, rather than to linguists who know better. Breaking News There is now an excellent ELU blog article titled . It is highly recommended reading. |
Inflation, in the ordinary sense, increase in the prices of goods and services. Some economists say inflation up to 5% is even desirable. Why is this so? When governments struggle to control inflation, why is desirable? | Is inflation a good or bad thing? Why do governments want some inflation? |
i bought Dell Vostro 2520 in which Ubuntu was already installed. i want to uninstall Ubuntu and install win7 on that machine. For that i used Gparted on Ubuntu and had eraseed partiion of Ubuntu. And for install win7 i used win7 DVD from Boot optionn, But laptop not getting boot via DVD. even i tried bootable Pan drive of Win7 but had same problem. i have Ubuntu live cd. is there any solution for this problem? plz show me step by step. | I have absolutely no experience with Linux, and I desperately need to get my computer back up and running again with Windows. How do I remove Ubuntu and reinstall Windows? Editor's note: many of the answers are about removing Ubuntu from dual-boot but keeping Windows (which is a bit complicated), while other answers are about removing Ubuntu from single-boot (which is easy: basically just format the disk while installing Windows). The question as written is ambiguous between dual-boot or single-boot. |
Im Overlaying/ Over Dropping my face onto a video i want. im a beginner so i dont know if ive just done something wrong in the process but ill try to be precise. ok, so the frames and resolution for both files are different so i set in the properties bar to the gameplays resolution/positioning at 1280px720p at 29.97fps what ive done is ive added the first file witch is the game im playing (1280px720p, 29fps) ive then add my face (1920x1080p at 29fps), I split all the vid and audio files so that they are all at the same length, i then transformed the vid of my face, scale it down, position it where i want and over drop it over the game. sounded right to me right??... I dont know, but after i did all the processes it played horridly, then id let it play through and on the second round play at 30 fps for about 10 sec then drop down to 20 or less. I cant figure out why it does this... | Am learning Blender for video editing and having a great time with it (brain hurts a bit, though). Have added the gamma cross effect to a project and it is all working beautifully, except ... as the fade in happens using the gamma cross, the frame rate drops to 25fps. The project is in 50fps. All worked fine with no dropped frames at 50fps prior to adding the effect. On Xubuntu-core 15.10 and Blender 2.74. GTX 970, 16Gb RAM and i7 6700. TIA and just ask if any further info required. |
Simple question I own a domain and from that domain i want to redirect users who opens my old domain URL to my New Domain URL. | This question is here so we can offer users who are looking for information on how to make one or more common or basic redirects in Apache using the htaccess file. All future questions pertaining to finding information that is that is covered by the question should be closed as a duplication of this question. . Whats the point in this question? The idea while not perfect is catch the most commonly asked questions regarding redirects using the htaccess on the Apache platform either on some type of lamp or a live server. The type of answers should be generally those that you could imagine are used by 100,000’s of sites world-wide and are constantly asked here at Pro Webmasters repeatedly over and over in various forms. A few examples of the type of answers we are looking for: How can I redirect non-www to www? How can I redirect a sub domain to the main domain? How can I redirect a sub folder from domain to a root or a subdomain? How can I redirect an old URL to a new URL? A few examples of the types of answers that we are not looking for: Answers that do not involve a redirect. Any answers relating to NGinx, IIS or any other non-Apache platform. Answers that involve custom and complex string or query removals. Resources for Advanced to Complex Mod_Rewrite Rules: Please note: that this question is still in construction and may need some refining either by myself or a real moderator of Pro Webmasters, if you have any concerns or questions . |
Looking at the image attached the problem is self-explanatory. The tabs and icons within the software (photoshop in this particular case) are extremely small so that they are barely visible and difficult to use. It happens to some of the software just installed in a newly bought pc(very high resolution screen). How can I resize them specifically (I know the trick for general resizing). Would the software "sizer" help? | We know that with the Windows 10 feature Display Scaling is possible to change the size of text, apps and icons. Once you set a value, this is applied to ALL texts, apps and icons. I just want to set this feature for specific apps. One example: 125% is set to default, but when I use an IDE like Eclipse or Visual Studio I want the scaling at 100%. Is it possible? |
How do you change the language on Google Play? I'm American, so I want it in English. I live in Luxembourg, have a Lux SIM card and bought my phone in Thailand and yet the Google Pay Topics are all in Italian. I lived in Italy years ago but I'm not using anything that I got in Italy. I've tried clearing the cache on the app, but I get the same thing and it's also on my laptop, which I purchased recently in Lux as well. It's really annoying. How can I change it? Please help. | I live in Hong Kong, and the Play Store displays everything in the local Cantonese language. I have set everything I can (Android language, Account language, even the app locale via Xposed Module "App Settings") to English, but I still see all the categories in the store in Chinese. Can someone help me change those to English? (Click image to enlarge) |
In connection to question, I am wondering how to calculate value $\langle \psi|\phi \rangle$ for arbitrary quantum states $|\psi\rangle$ and $|\phi\rangle$. A swap test is able to return only $|\langle \psi|\phi \rangle|^2$ which means that sign of the product is forgotten in case the inner product is real. Moreover, information about real and imaginary parts is lost in case of complex result. Do you know about any more general method how to calculate the inner product than swap test? | I've been searching for a quantum algorithm to compute the the inner product between two $n$-qubit quantum states, namely $\langle\phi|\psi\rangle$, which is in general a complex number. One can get $|\langle\phi|\psi\rangle|^2$ through thte SWAP test for multiple qubits, but this is not really the inner product as the information of the real and imaginary parts are lost. I came across this , which claims that the task can be done by simply using CZ gates. I'm not sure if I am mistaken, but it seems to me that such a circuit works for computational basis states, but not for general quantum states. Could somebody help me confirm if this is actually the case? If the above algorithm doesn't work for general quantum states, what algorithm would you suggest? |
When I execute a grassgis alogrithm in Qgis I always get following error: 'ascii' codec can't encode character u'\xfc' in position 23: ordinal not in range(128) See log for more details and This algorithm cannot be run :-( It seems that GRASS GIS 7 is not correctly installed and configured in your system. Please install it before running GRASS GIS 7 algorithms. In processing opitions I set the path for grassgis to C:\OSGeo4W64\apps\grass\grass-7.2.0, same for grassgis docs. There is no option for setting the path to msys. I reinstalled whole OSGeo4W with coustom options and installed all available options. No result. | Windows 7, OsGeo4W pack installed including QGIS 2.4.0 and GRASS. In QGIS when I try to execute a GRASS geoprocessing algorithm I get this popup: Missing dependency. This algorithm cannot be run :-( This algorithm requires GRASS GIS 7 to be run. Unfortunately, it seems that GRASS GIS 7 is not installed in your system, or it is not correctly configured to be used from QGIS Click here to know more about how to install and configure GRASS GIS 7 to be used with QGIS The link doesn't help. I get the same message at my computer at work with QGIS 2.2.0 The GRASS plugins are activated under geoprocessing settings. Do I need to configure something? When I run MSYS I get this: |
I have a large number of LiDAR files (in .asc format) that I'm wanting to catalogue so it is easier for people to find the files they want. How can I take LiDAR files I have, and create a .shp file (ideally polygons) of the areas covered. My end goal is to have a .shp file people can open on top of a map, check whether or not their location has been covered by LiDAR and then identify the file name that they're after. | I am working in QGIS 2.10.1 and I have the following situation: I have some Landsat8 scenes (different paths and rows) and I want to extract their boundary. My final objective is to superimpose them to the vector of my study area, so that I can show how the scenes cover the study area and in which points they overlap. I have already tried to convert the raster into a vector, but QGIS cannot make it, it crashes or it gives me back only part of the polygon. Is there anybody who's got an idea to solve this problem? |
I have a script where I am passing commands to processes with an arguments passed from command line and from environment variables as well. To simplify my use case lets assume my processes are echo command. I noticed that variable expansion is more easy for numeric variables $1 passed from command line than for environment variables $VAR. For numeric variables I don't need to have white spaces around to make it work, see example below: f1() { echo "this is 1 $1 and var $VAR done" } VAR=2 f1 1 #this is 1 1 and var 2 done f2() { echo "this_is_1_$1_and_var_$VAR_done" } VAR=2 f2 1 #this_is_1_1_and_var_ As you can see, if I replace spaces with underlines, then named variable is no longer interpreted while numeric variable still works fine. I learned how to workaround this limitation by extra quoting f3() { echo "this_is_1_$1_and_var_""$VAR"'_done' } VAR=2 f3 1 #this_is_1_1_and_var_2_done The problem is that my script requires quite a lot of substitution in long SQL statements. Putting extra quotes in each places will make it much more difficult to read and maintain. Therefore I would find it useful to mimic command line argument but it (obviously) doesn't work: 1=echo $VAR $1 Is there any trick I can make it work? | I can write VAR=$VAR1 VAR=${VAR1} VAR="$VAR1" VAR="${VAR1}" the end result to me all seems about the same. Why should I write one or the other? are any of these not portable/POSIX? |
The section appears like "1 XXXXXXX", and I want something like "1. XXXX". I've been looking for some way to change it using \renewcommand, but nothing happens. Can you help me? P.D. I am using the "Article" format. | I wonder is there any way to change the format of section numbering from 1.1 to 1.1. ? I know this is trivial, but I really need to add one more dot after the section number. Does anybody know how to do that? Thanks a lot |
I wanted to ask, is there any possibility to determine the Windows version via the application, I have made some research, but haven't found, Thank you in advance ^^ | How do you check the windows version in Win32 at runtime? |
I'm looking for a very low level website blocker for MacOS. Let's say that I want to block Twitter. I want to block it in a way that I can't unblock it without reinstalling the operating system. I'm aware of software such as: or browser extensions or changing the DNS or host file. But these are too easy to disable. Also Screen Time by Apple doesn't work. I want to block distracting websites from ever working on my Macbook. Does something like this exist? Or if not, is it possible to create something like this? | I know I can block websites in Parental Controls, but accessing that option requires the "Limit Adult Websites" option, which I find to be overly strict. Is there a way to block specific websites without third-party software? I'm running High Sierra on my laptop. |
If I have the following $n \times n$ matrix $$\begin{bmatrix} 2 & 3 & \cdots & n+1\\ 3 & 4 & \cdots & n+2\\ \vdots & \vdots & \ddots & \vdots\\ n+1 & n+2 & \cdots & 2n\\ \end{bmatrix}$$ how can I determine its rank? I know that I need to check for the maximum number of linearly independent columns. However, I’m having a hard time determining the linearly independent columns. Thanks for those who’ll help. | Let $A$ be a $n\times n$ matrix with entries $a_{ij}=i+j $ . Calculate rank of $A$. My work : I noticed that A is symmetric . Hence all of its eigen vectors are real .. That is all i have got . Your help will be highly appreciated .Thank you . |
I use DB 'Mysql 14.14 Distrib 5.7.24' and the OS is 'Ubuntu 18.04' The DB server have local IP : 10.0.211.198 And For The application IP : 10.0.214.198 when I try connect form application server to db I get error in the connection but After I read it I found the mysql client change IP to Application IP as below screen But when I try connect using telnet its successfully connected. I try to remove db and reinstall it also try different client to connect and its same result. Thank you | I have a remote MySQL server running on x.x.x.x. And there is a database named abc. I can do the following mysql -h x.x.x.x -uroot use abc But when I try to mysql -h x.x.x.x -uroot --database=abc I get ERROR 1044 (42000): Access denied for user 'root'@'%' to database 'abc' Why is that? And how do I fix it? edit: I have now resolved the issue by doing the following: ssh in the box run mysql -uroot GRANT ALL PRIVILEGES ON *.* TO 'root'@'%' WITH GRANT OPTION; But I still don't understand why. mysql> SELECT USER(),CURRENT_USER(); +-----------------------------+----------------+ | USER() | CURRENT_USER() | +-----------------------------+----------------+ | [email protected] | root@% | +-----------------------------+----------------+ mysql> SHOW GRANTS FOR root@'%'; +------------------------------------------------------------------+ | Grants for root@% | +------------------------------------------------------------------+ | GRANT USAGE ON *.* TO 'root'@'%' | | GRANT ALL PRIVILEGES ON `mydb`.* TO 'root'@'%' WITH GRANT OPTION | +------------------------------------------------------------------+ mysql> SELECT CONCAT(QUOTE(user),'@',QUOTE(host)) from mysql.user WHERE user='root'; ERROR 1142 (42000): SELECT command denied to user 'root'@'Maxs-MacBook-Air.local' for table 'user' Max |
We use iis 6 to send out emails for our website but some email addresses bouce backs. It only appears to be 2 addresses. There is at least 100 different email addresses sent to at the same time as these. Here are the 2 different messages we get. First one. You do not have permission to send to this recipient. For assistance, contact your system administrator. secure.example.com #5.7.1 smtp;550 5.7.1 Fix reverse DNS for xx.xx.xxx.xxx or use your ISP's mail server Second one. Could not deliver the message in the time limit specified. Please retry or contact your administrator. secure.example.com #4.4.7 Not sure if they both relate to reverse dns. If you can help or require more information please let me know. | I started a new service and we need to send emails to our customers (new account confirms, etc). My server is known as prod01.bidrodeo.com and resolves to 97.107.134.38 . For reverse DNS, 97.107.134.38 resolves to prod01.bidrodeo.com . However, all our email addresses are in the form of [email protected]. Should I make the reverse DNS point to bidrodeo.com instead? My emails are getting delayed or rejected by certain systems and i am not sure if my reverse DNS is not set up correctly. |
I'm working on the CSS for a website for a project and my Footer DIV has decided it wants to get out and see the wide world. All the elements inside the footer are displaying correctly, they're just deciding to float over the top of my content DIV/ I've tried an absolute to get the thing to stay put and had zero luck with that. It will stay put if i used a 'fixed' but I'm not happy with how that looks. This is how the footer is defined in my CSS sheet. footer { float: left; width: 960px; height: 40px; background-image: url("images/footer.jpg"); background-repeat: no-repeat;} Here's how the Footer is implemented at the bottom of the Index.html page <div id="footer" class=copyright> <p>Copyright 2019- Nature Snap Photography Site Maintained by____</p> </div> </div> </body> </html> | I have a simple 2-column layout with a footer that clears both the right and left div in my markup. My problem is that I can't get the footer to stay at the bottom of the page in all browsers. It works if the content pushes the footer down, but that's not always the case. |
Find a positive integer $n$ such that $n/2$ is a square, $n/3$ is a cube and $n/5$ is a fifth power. Above problem was given in the text “An Introduction to the Theory of Numbers” by “Ivan Niven and Zuckerman". I tried to generalize the problem statement as: Find a positive integer $n$ such that $n/2$ is a square, $n/3$ is a cube, $n/5$ is a fifth power, $n/7$ is a seventh power ... $n/p_{k}$ is a $p_{k}$-th power. I have found the solution for this and trying to generalize it more. Now, How can I know that this work is authentic i.e. it has not been done by anyone earlier? Any sort of help is welcomed. | Show that there are infinitely many $N$ such that $\frac{N}{2}$ is a perfect square, $\frac{N}{3}$ is a perfect cube, and $\frac{N}{5}$ is a perfect fifth power. A hint is given with this question, which is: $7^{30}$ is a perfect square, a perfect cube and a perfect fifth power. Can anyone solve this? Thanks! |
Linda read a novel which is written in English, ? (A) does she (B) doesn't she (C) did she (D) didn't she The answer is "(c) did she", but why is it (c) and not "(D) didn't she"? These aren't your dictionaries, ? (A) are these (B) aren't these (C) are they (D) aren't they The answer is "(C) are they", why is it not "(A) are these"? | We always use a positive tag question after a negative sentence: You shouldn't take this medicine, should you? We use a negative tag question after a positive sentence: She must leave early, mustn't she? But when there is a negating prefix on the adjective (impatient vs. patient) after the verb "to be", then the sentence is negative in meaning. Does this mean the tag should be positive? Which is correct, A or B? A: I am impatient, am I? B: I am impatient, aren't I? A: The class was dismissed, was it? B: The class was dismissed, wasn't it? |
I'm making a 1.12 map that need to do something when a player join. I tried stats.leavegame method, but if the game crashed the last time, the command won't run. No file permission for it's hard to share, but unintended file type (like using a file to take the place of a folder, in my answer) is fine | Is there any way to run a command automatically when a player joins the server? I need to do this without the use of a Bukkit plugin. I think it's possible with MCP but I want to know how! |
I want to delete all materials on all meshes and only add one default material to all meshes? I tried the "Copy Material to Others", but it's not working. I still have some materials somewhere. Like this in the box: EDIT: OK, I got it now. The problem was, that some objects were hidden. So the "Copy Material to Others" didn't worked. When you open the file, then first press "Alt + H" to unhide all objects. Then do the "Copy Material to Others". Save file and open it again. | Is there a quick way to delete all materials in the scene? I have a scene containing 20+ materials and all linked to objects. I'd like to remove all the materials from my blender file. |
One of my answers on Ask Ubuntu meta reached the lofty heights of 25 upvotes and the relevant badge was duly awarded. However, I seem to keep getting the notifications: Note that only the notification was received in triplicate. The badge was only awarded once. | Not sure if someone else has already raised this - I've got eleven notifications that I've received a Caucus badge on English Language Learners. Perhaps one notification for each community that I'm a member of? I am a member of the community, and did visit the election. Also, the badge hasn't been awarded more that once (so I think it's just the notification that's at fault). Note that this seems to happen for other badges, it has been reported for: Caucus, Nice Answer, Enthusiast. |
I am studying Galois theory and have come across many questions regarding finding the splitting field of $x^n-a$ over $\mathbb{Q}$. The specific question I was looking at was Let $L$ be the splitting field of $x^6-2$ over $\mathbb{Q}$. Determine $[L:\mathbb{Q}]$ and describe the Galois group. In this case I know that $L=\mathbb{Q}(\sqrt[6]{2}, i\sqrt{3})$. I think the degree would be $12$ since the minimal polynomial of $\sqrt[6]{2}$ is $x^6-2$ and the minimal polynomial of $i\sqrt{3}$ is $x^2+3$ and the former is nonreal, so we can multiply the field degrees. I don't know how I would find the Galois group. And are there any methods that would work more generally? | I have some problems with this exercise. I don't know if it can be done. Consider the polynomial $ x^n - a \in \mathbb{Q} $ Can I compute the Galois group of this over $\mathbb{Q}$? Maybe having a nice "basis. The splitting field is given by $\mathbb{Q}(\zeta_n,\alpha)$ , where $\zeta_n$ is a primitive root of unity , and $\alpha$ is some number such that $\alpha^n = a $. Well first of all, I want a $\underline{"good basis"}$ for the splitting field. In the sense that the minimal polynomials, of the adjoined elements, are different (in this case the computation of the galois group is very simple). For example one easy case, it's when $a>0$, then $(a)^{\frac{1}{n}} \in \mathbb{R}$ , so clearly the minimal polynomial of $(a)^{\frac{1}{n}} , \zeta_n$ are distincs, and I'm done. If $n$ is odd then , it's also easy, since one root it's also real, for example $x^3-3 $, the real root is $ \root 3 \of { - 3} = - \root 3 \of 3 $ , so I can consider the splitting field as $\mathbb{Q}(-\root 3 \of 3 , \zeta_3 )=\mathbb{Q}(\root 3 \of 3 , \zeta_3 )$. The difficult case is when $n$ is even and $a<0$ , for example $x^8+20$ or $x^4+20$ in some cases as in the second, there are particular cases since there exist algorithms for the Galois group of quartics, but in general. It can be done? $\underline{Remark}$ I'm searching a $\underline{"good basis"}$ for the splitting field. In the sense that the minimal polynomials, of the adjoined elements, are different since in this case the computation of the galois group is very simple. |
I have tested the following code to verify some simple numerical outputs when std::setprecision is used in C++: double f1 = 3.1415; std::cout << std::setprecision(4) << f1 << '\n'; double f2 = 1.2345; std::cout << std::setprecision(4) << f2 << '\n'; The corresponding outputs are: 3.142 1.234 Why is 1.234 not being rounded to 1.235? Furthermore, if we change f2 to 1.2315, then the rounding in the output does happen, and the output is 1.232. Is there any rule of thumb to follow when using setprecision to format the output of numeric values? | Consider the following code: 0.1 + 0.2 == 0.3 -> false 0.1 + 0.2 -> 0.30000000000000004 Why do these inaccuracies happen? |
If I map through an array using parseInt it returns unexpected and incorrect results: console.log(["1234-04-23", "1234", "04", "23"].map(parseInt)) // => [1234, NaN, 0, 2] but redundantly adding an arrow function wrapper works as expected console.log(["1234-04-23", "1234", "04", "23"].map(e => parseInt(e))) // => [1234, 1234, 4, 23] These two statements should behave identically, so why does the first one break? | From the : [1,4,9].map(Math.sqrt) will yield: [1,2,3] Why then does this: ['1','2','3'].map(parseInt) yield this: [1, NaN, NaN] I have tested in Firefox 3.0.1 and Chrome 0.3 and just as a disclaimer, I know this is not cross-browser functionality (no IE). I found out that the following will accomplish the desired effect. However, it still doesn’t explain the errant behavior of parseInt. ['1','2','3'].map(function(i){return +i;}) // returns [1,2,3] |
This is probably a pretty simple question, but I'm tying myself in knots over it. We're all familiar with the Reflection Theorem, Lowenheim-Skolem Theorem, and Mostowski Collapse Lemma for getting countable transitive models of finite fragments of ZFC. You take a finite fragment $\Gamma$, use the reflection theorem to get that $\Gamma$ holds in some $V_\kappa$, Skolemise over $V_\kappa$, and then Collapse to a ctm. My question. Is there (or could there be) a countable transitive model satisfying the same first-order truths as $V$? Obviously, by Tarski, such a countable transitive model is not first-order definable. A possible route: Suppose full second-order reflection is true of $V$. Let $A$ be a second-order parameter that contains a witness for every parameter-free sentence of first-order $ZFC$ true in $V$. Then, just reflect the sentence $x \in A$, Skolemise, and Collapse as normal (I feel like I might be pulling a fast-one here). | From $\mathrm{ZFC},$ define a new theory $\mathrm{ZFC}^E$ by adjoining a constant symbol $E$ together with axioms to the effect that: $E$ is countable and transitive $(E,\in)$ is an elementarily equivalent to $(V,\in).^*$ (This is an axiom schema). Question. Is $\mathrm{ZFC}^E$ outright inconsistent? Motivation. The idea (or motivation) is to have a "miniature copy" of the universe available, that is nonetheless "very small" from our omniscient $V$-like perspective. |
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