I have a list of items with a property code and I want to group by eventId and create a table representation where code values are transformed to columns. Every triple (event, code,amount) is unique.  I want to transform this  eventId code  amount     1      A     100   1      B     101   1      C     102   2      A     103   2      C     104   3      B     105   ....   to this   eventId  A    B   C  1      100  101 102  2      103   0  104  3       0   105  0  ...    var table=from x in list     group x by x.eventId into gr     select new            {               eventId=gr.Key,               ....            }


Why can I not use the Make Segments command on my Surface NURBS Curves?

I followed the tutorial on the , and then I created a simple test. I created a Surface NURBS curve, made 3 copies with space between them, selected all, and hit F, but nothing happened. No error or any indication that F is supposed to do anything was displayed. I am new to Blender and am using version 2.70, so not sure what I am doing wrong. Any ideas?


I have this little script here: #!/bin/bash  for i in {"$@"} do  echo "fping -g $@" done  fping command in used for scanning purposes. I want to feed it with multiple arguments but when I execute the script it passes all positional parameters at the same time. fping -g 1 2 3 4 fping -g 1 2 3 4 fping -g 1 2 3 4 fping -g 1 2 3 4  My goal is to have it like this : fping -g 1 fping -g 2 fping -g 3 fping -g 4  Could you help?


No error on code but application crash when perform function. Logcat show FATAL EXCEPTION on (MainActivity.java:623)

I've been creating a Bluetooth application, everything works fine from turn On and OFF, search device, visible device, open server, set client. Everything works fine and the device could be paired. But when I want to perform data transfer using Input/OutputStream the crash begin.  The code had NO ERROR, but when performing connectedThread function it crashes. here is the code  private class ConnectedThread extends Thread {      private final BluetoothSocket mySocket;     private final InputStream myInStream;     private final OutputStream myOutStream;      public ConnectedThread(BluetoothSocket socket) {         mySocket = socket;         InputStream tmpIn = null;         OutputStream tmpOut = null;         try {             tmpIn = socket.getInputStream();             tmpOut = socket.getOutputStream();         } catch (IOException e) {         }          myInStream = tmpIn;  <-------MainActivity.Java:623         myOutStream = tmpOut;     }      public void run() {         byte[] buffer = new byte[1024];         int begin = 0;         int bytes = 0;         while (true) {             try {                 bytes += myInStream.read(buffer, bytes, buffer.length - bytes);                 for (int i = begin; i < bytes; i++) {                     if (buffer[i] == "#".getBytes()[0]) {                         myHandler.obtainMessage(1, begin, i, buffer).sendToTarget();                         begin = i + 1;                         if (i == bytes - 1) {                             bytes = 0;                             begin = 0;                         }                     }                 }             } catch (IOException e) {                 break;             }         }     }      public void write(byte[] bytes) {         try {             myOutStream.write(bytes);         } catch (IOException e) {         }     }      public void cancel() {         try {             mySocket.close();         } catch (IOException e) {         }     }       Handler myHandler = new Handler() {         @Override         public void handleMessage(Message msg) {             byte[] writeBuf = (byte[]) msg.obj;             int begin = (int) msg.arg1;             int end = (int) msg.arg2;              switch (msg.what) {                 case 1:                     String writeMessage = new String(writeBuf);                     writeMessage = writeMessage.substring(begin, end);                     break;             }         }     };  }   The connectedThread is trigered from here  transferBtn.setOnClickListener(new View.OnClickListener() {             @Override             public void onClick(View v) {                 ConnectedThread t = new ConnectedThread(socket);<------MainActivity.Java:192                 t.start();         });   The Logcat show this     07-14 02:53:04.937  16812-16812/com.example.heszrave.bluetoothremote E/AndroidRuntime﹕ FATAL EXCEPTION: main       java.lang.NullPointerException               at com.example.heszrave.bluetoothremote.MainActivity$ConnectedThread.(MainActivity.java:623)               at com.example.heszrave.bluetoothremote.MainActivity$6.onClick(MainActivity.java:192)   When I click on MainActivity.Java:623, it pointed to myInStream = tmpIn; for MainActivity.Java:192 it pointed to the firing event ConnectedThread t = new ConnectedThread(socket);


Proving that determinants of matrices are linear transformations

How do you prove that a determinant is a linear transformation using the properties: $T(cx)=cT(x)$ and $T(u+v)=T(u)+T(v)$?  For instance, if you had a $3\times3$ matrix: $(1,1,2)+(x,y,z)+(1,2,1)$, how would you prove that taking its determinant with respect to the vector $(x,y,z)$ is a linear transformation?


Button generated with jQuery doesn't work

I create a list of buttons with this instruction:  $("ul#cards").append("
<button id="modifiedCard" type="button" class="btn btn-primary btn-xs pull-left">Modified</button>
");   Ok, it works. Buttons are generated correctly.   In the same page I wrote:  $("#modifiedCard").click(function () {     alert("Hello!"); });   But, when I click on one of them the alert doesn't start.   I tried with:  <button id="modifiedCard">Try</button>   and the alert starts.  Why?


Laptop battery critically low cannot remove notification

I installed and used Linux for the first time - Ubuntu 18.04.01 LTS. My laptop's battery is almost dead sitting on 0% and the notification keeps popping every 5 minutes.  Is there any way to disable the notification?    tried dconf editor' tweeks set critical on -5 level instead of 0  but didnt work. i have read every other question here and didnt solve my problem . also my latpop is a toshiba satelite p50-b which means battery cannot be unmounted   Here's a screenshot that might be useful:


In the Final Battle, when you remove doom tokens for rolling successes against an Ancient One do you stop counting successes for that roll?

In Arkham Horror you have to roll a cumulative number of successes equal to the number of players to knock off a doom token from the Elder God's health. If you reach the number of players worth of successes do you then stop counting for the player and move on or do you count the extra successes against the next doom token?  We played it so that you kept on adding them but it meant that we turned Nyalothotep into mince meat quite quickly (One Character was blessed had a fight of 6 a shotgun and Fight +1 skill card though)


Applying over 200 textures to a single model

I downloaded a bus model from a website that came with a fbx file and a folder containing 226 png texture files. I just don't know how to apply all those texture files to model. The screenshot shows the shading editor with a purple coloured bus (indicating that textures have not yet been applied I guess). On the left side are some of the listed textures.


Suppose I have some dataset. I perform some regression on it. I have a separate test dataset. I test the regression on this set. Find the RMSE on the test data. How should I conclude that my learning algorithm has done well, I mean what properties of the data I should look at to conclude that the RMSE I have got is good for the data?


Installed Package information, specifically Status

Is it possible to get information on the package through APEX after it has been installed?  Specifically I want to know the Status (see below)    The reason I want this is because I want to show instructions how to purchase if the status is 'Trial'.


My ubuntu VERSION="14.04.3 LTS, Trusty Tahr"  I wanna upgrade svn client to >1.9 with below two commands  sudo apt-get remove subversion sudo apt-get install subversion   I thought it would automatically give me latest version, however it is 1.8.8. Did I miss something?


crontab does not work correctly python file ok

from datetime import datetime x="Hello, it is now %s." % datetime.now().strftime('%d-%m-%Y %H:%M:%S') import csv try:     with open('output.csv', 'w+') as csvFile:         writer=csv.writer(csvFile)         writer.writerow(x.encode('UTF-8'))         print(x.encode('UTF-8')) finally:     csvFile.close() import pandas as pd data = pd.read_csv('output.csv') data.to_excel('output.xlsx')   UBUNTU code  attyan22@LAPTOP-SGBTV53C:/tmp/sysv-rc-conf-0.99$ crontab -l * * * * * /usr/bin/python/c/Users/a.sakata/Desktop/python_lesson/hello_time.py   but it does not work, so I checked if top run or not  attyan22@LAPTOP-SGBTV53C:/tmp/sysv-rc-conf-0.99$ sudo apt-get install chkconfig Reading package lists... Done Building dependency tree Reading state information... Done Package chkconfig is not available, but is referred to by another package. This may mean that the package is missing, has been obsoleted, or is only available from another source  E: Package 'chkconfig' has no installation candidate attyan22@LAPTOP-SGBTV53C:/tmp/sysv-rc-conf-0.99$ sudo apt-get install sysv-    rc-conf Reading package lists... Done Building dependency tree Reading state information... Done E: Unable to locate package sysv-rc-conf   it cannot install  why how


Could you provide a step-by-step for dummies explanation of how Hamiltonian Monte Carlo work?  PS: I've already read the answers here, , and here, , and here,  and they do not address it in a step-by-step way.


2-morphisms for 2-category: don't understand how to draw


How do I create a sphere with six circles cut into it?

I'm attempting to model BB-8 from The Force Awakens, but I'm struggling to create the base shell of his body. He's essentially a sphere with 6 equally spaced circles cut out of its surface. The remaining shape is then cut into 8 segments, like here:    If I could even create one of the segments I could then duplicate it.  Any help is appreciated!


Is every convex function on an open interval continuous?

Let $f:(a,b)\rightarrow \mathbb{R}$.   $f$ satisfied the following property:  If $\forall x_{1},x_{0},x_{2}\in(a,b)$ and $x_{1}<x_{0}<x_{2};$then$\frac{f(x_{0})-f(x_{1})}{x_{0}-x_{1}}\geq \frac{f(x_{2})-f(x_{0})}{x_{2}-x_{0}}.$   My question : whether the function $f\in C((a,b))?$    We can get  $\displaystyle\frac{f(x_{1})-f(x_{0})}{x_{1}-x_{0}}\geq \frac{f(x_{2})-f(x_{0})}{x_{2}-x_{0}}. $Let $\displaystyle g(x)=\frac{f(x)-f(x_{0})}{x-x_{0}},$ if we can prove $g(x)$ is bound and  decreasing (not strictly ) in $(x_{0}-\delta ,x_{0});$ then we have $f^{'}_{-}(x_{0}) $ exists .In a similar way ,$f^{'}_{+}(x_{0}) $ exists.  $f^{'}_{-}(x_{0}) $ exists $\Rightarrow\displaystyle\lim_{x\rightarrow x_{0}-}f(x)=f(x_{0});$ $f^{'}_{+}(x_{0}) $ exists $\Rightarrow\displaystyle\lim_{x\rightarrow x_{0}+}f(x)=f(x_{0}).$  Obviously, $f$ is coutinuous at $x=x_{0}.$Further, $f\in C((a,b))!$     But  I failed to prove  $g(x)$ is bound and  decreasing (not strictly ) in $(x_{0}-\delta ,x_{0}).$Sometimes  I doubt the conculsion that  $f\in C((a,b)).$  Either make a counterexample to deny it ,or prove the conculsion is correct?


I know that  $\left ( -1 \right )^{2/3}=\left ( \left ( -1 \right )^{2} \right )^{1/3}=1$  But Matlab computes this as $- 0.5 + 0.8660254038i$ a complex number.Why?


How to format a USB or external drive in 13.04?

I am using Kubuntu 13.04. How to format a USB or external drive?


Why do objects have to be initialized first before use ? Constructor function vs Object.create

I made my object a constructor function cause I did not want to put my code in another file or my object on top. Why do objects have to be initialized before use if a function does not and a function is considered an object ?   var foo_f = new Foo_methods;  var foo_o = Object.create(null); foo_o = Object.create(foobar_obj);  foo_f.name() //Works, functions can be initialized anywhere.  foo_o.name() // Error you have to put the object on top  function Foo_methods(){    this.name = function(){ console.log("I am foo in Foo_methods")} }  //If I put this on top or in another file it works. If I don't I get an error //Type Error: Object prototype may only be an Object or null: undefined  var foobar_obj = {           name:function(){ console.log("I am foo in foobar_obj")} }


My family and I are traveling to Dubai via Istanbul from Abuja, Nigeria. The layover is 12 hours. We have 2 little children, 1 infant and a senior in our party, all on Nigerian passports. I want to know if we require a transit visa and whether the facilities in the transit area good enough to stay there 12 hours if we decide to. We are flying Turkish Airlines.


How can I make the result to be the same in C++ and C# of double values

Please notice that I am not asking why a double value changes into another precision, but how can I make the results to be the same.  I appreciate all the comments and answers below, but I didn't get a solution to my problem.  My question again.  I just met a problem when rewriting the code from C++ to C# of the precision problem in double value,  I have a method to calculate the result of a financial product of several double values, but when I compare the results, I got different but similar results from C++ and C# program due to the precision of the double value.  I debug the program in C++ I found that after I set the values to a and b double a = 4.9; double b = 5.1;  The value of a and b changes to, a is 4.9000000000000004 and b is 5.0999999999999996. But in C#, a is still 4.9 and b is still 5.1, and finally, I got the results of -0.062579630921710816(C++ result), and -0.062579644244387111(C# result)  I am totally new in C# and C++, so are there any solutions to make the calculation result to be the same, please (I cannot change the C++ code)? Or is it possible to make the calculation result to be the same?


Block Internal Traffic from Google Analytics for Remote Team Members

We are 100% remote, meaning no office. Currently I have an IP filter that blocks the IP of every single team member but this is not manageable since A) It's a pain to get everyone to send me their IP address B) It's messy to setup, C) An IP address can change and D) Several team members, including myself, tend to have different working spots during the day.  Also we've thought about using browser extensions but not everyone uses Google Chrome, some use Safari, others Edge...  What's the best way to block internal traffic for a remote team?


How can I solve this sum?  $$S_{n} = \sum_{k=1}^{n} k \Big( \frac{3}{2} \Big)^{k-1}$$  Worth noting: I can use lower index $k = 0$ instead of $k = 1 $, because the result does not change.  I have tried using "perturbation method".      Perturbation method:      $$S_{n} + x_{n+1} = x_{0} + \sum_{k=1}^{n+1} x_{k}$$      $$S_{n} + x_{n+1} = x_{0} + \sum_{k=0}^{n} x_{k+1}$$   My attempt:  $$S_{n} + (n+1) \Big( \frac{3}{2} \Big)^{n} = \sum_{k=0}^{n} (k+1)\Big(\frac{3}{2}\Big)^{k}$$  $$S_{n} + (n+1) \Big( \frac{3}{2} \Big)^{n} = \underbrace{\sum_{k=0}^{n} k \Big(\frac{3}{2}\Big)^k}_{\text{stuck here}} + \sum_{k=0}^{n} \Big(\frac{3}{2}\Big)^{k}$$  I have tried perturbing the "stuck here" sum, but it leads to infinite loop of perturbations, I think.  I'm new to sums and sequences so I don't know the tricks yet, and I think I am missing something simple to solve it.   WolframAlpha gives result:  $$\sum_{k=1}^{n} k \Big( \frac{3}{2} \Big)^{k-1} = 2 \Bigg( \Big( \frac{3}{2} \Big)^n (n-2) + 2 \Bigg)$$ Thanks for tips.


I am trying to record a video with Quicktime Player but whenever I record it shows a green screen. When I try to watch the video when I record the screen:   P.S I am using an iMac...


I wrote some algorithms using pseudocode, but when compiling the document, each algorithm ends with =0 (at line\end{algorithmic}). What I have to do to avoid this problem?


Nullable types: better way to check for null or zero in c#

I'm working on a project where i find i'm checking for the following in many, many places:  if(item.Rate == 0 || item.Rate == null) { }   more as a curiousity than anything, what's the best way to check for both cases?  I've added a helper method which is:  public static bool nz(object obj) {     var parsedInt = 0;     var parsed = int.TryParse(obj.ToString(), out parsedInt);     return IsNull(obj) || (parsed && parsedInt == 0); }   Is there a better way?


Python loop through all possibilities of regex

I have a list of strings that include some regular expressions-like strings that define ALL possible matches to form new strings. Example:  Source  Id[0-1][2-3]_Pos[1-3] foo01_bar[A-C]   Is there any way in Python I can loop trough all possibilities and create new strings from it? So, the example above shall deliver:  Target  Id02_Pos1 Id02_Pos2 Id02_Pos3 Id03_Pos1 Id03_Pos2 Id03_Pos3 Id12_Pos1 Id12_Pos2 Id12_Pos3 Id13_Pos1 Id13_Pos2 Id13_Pos3 foo01_barA foo01_barB foo01_barC   Any hints are welcomed.  Update:  A working example of the answer can be found here:


Compact open topology on space of continuous maps from a discrete space is a product

I'm really confused with the statement.   let $X$ be a set endowed with the discrete topology and let $Y$ be any topological space. Show that $M(X,Y)$, the space of continuous maps from $X$ to $Y$ endowed with the compact open topology, is homeomorphic to the topological product $ \prod_{x \in X} Y_x$, $Y_x = Y$.  Can you please explain what we really have to prove?


Code displays hexadecimal value instead of string after string concatenation

The below code takes 3 words on 3 different lines. The first word should be changed like all vowels should be replaced by %. The second word should be changed like all consonants should be replaced by #. The third word should be changed like all char should be converted to upper case. Then concatenate the three words and print them. For eg 1st, 2nd, 3rd` words are respectively: how, are, you  Then, the result should be: h%wa#eYOU  However, I get the result as: [C@4769b07b[C@cc34f4dYOU  My code is: Scanner sc = new Scanner(System.in); String fword = sc.nextLine(); String sword = sc.nextLine(); String tword = sc.nextLine().toUpperCase(); char[] arr1 = fword.toCharArray(); char[] arr2 = sword.toCharArray(); for (int i = 0; i < arr1.length; i++) {     if (arr1[i] == 'a' || arr1[i] == 'e' || arr1[i] == 'i' || arr1[i] == 'o'             || arr1[i] == 'u' || arr1[i] == 'A' || arr1[i] == 'E'             || arr1[i] == 'I' || arr1[i] == 'O' || arr1[i] == 'U')         arr1[i] = '%'; } for (int i = 0; i < arr2.length; i++) {     if (arr2[i] != 'a' && arr2[i] != 'e' && arr2[i] != 'i' && arr2[i] != 'o'             && arr2[i] != 'u' && arr2[i] != 'A' && arr2[i] != 'E'             && arr2[i] != 'I' && arr2[i] != 'O' && arr2[i] != 'U')         arr2[i] = '#'; } String res1 = arr1.toString(); String res2 = arr2.toString(); System.out.println(res1 + res2 + tword);


What is ? As my book explains:     Gibbs energy is the energy of a system available for work.   So, what does it want to tell? Why is it free? Energy means ability to do work. What is so special about this energy? Can anyone simply explain?   I just want a math-free intuition.


Is there a way to accelerate or pre-cast spells with long casting times?

Some spells have casting times of 1m (Tsunami, Conjure Elementals, etc). I am a low level caster with no access to Wish. Is there a way to prepare the spell (maybe somehow pre-cast it the day before into an item) to be able to use it in combat in a single turn?  If I'm in a defensive position, I can combine a spell with Glyph of Warding. But the Glyph can't move too far, so it won't work if I'm storming the enemy castle and I need my trusty elementals. Spell scrolls and Rings of Spell Storing also maintain the spell's casting time, as far as I know. Sorcerers can only quicken 1 action to 1 bonus action.  What other options are there?


Prove $9^n \equiv 9 \pmod{24}\quad \forall n \in \Bbb N^*$

I accidentally found that $9^n\equiv 9\pmod{24} \quad \forall n \in \Bbb N^*$ But don't know how to prove it in an exact way. Please help


Is lens geometric distortion, chromatic aberration and light fall off still as much of an issue?

I saw an earlier question () that mentioned lower quality lenses have distortion, aberration and light fall off issues. Has software like Adobe Camera RAW come far enough along to correct these issues to an acceptable (less noticeable) level?   I use ACR often and I definitely see the distortion change when applying this adjustment. I can guess years ago before these software adjustments were around cheaper lenses suffered much more from this. I realize you can't "correct" for image quality, bokeh, aperture and those things, my question only relates to the issues in my title.   So my question is, has software corrections to lenses come so far that these three issues are no longer as important?


Paradox: Is $e^{i \frac{2\pi}{2} }$ equal to $1$ or $-1$?

$e^{i \frac{2\pi}{2} }=(e^{i 2\pi})^{1/2}=1^{1/2}=1$ where the last equality follows from $1*1=1$.  Meanwhile, $e^{i \frac{2\pi}{2} }=e^{i\pi }=-1$ by canceling out $2$.  How is this paradox related to the concept of branch in complex variable? Can some explain brach or branch cut in the context of this paradox? Thank you.


I know there are many ways to prevent image caching (such as via META tags), as well as a few nice tricks to ensure that the current version of an image is shown with every page load (such as image.jpg?x=timestamp), but is there any way to actually clear or replace an image in the browsers cache so that neither of the methods above are necessary?  As an example, lets say there are 100 images on a page and that these images are named "01.jpg", "02.jpg", "03.jpg", etc. If image "42.jpg" is replaced, is there any way to replace it in the cache so that "42.jpg" will automatically display the new image on successive page loads? I can't use the META tag method, because I need everuthing that ISN"T replaced to remain cached, and I can't use the timestamp method, because I don't want ALL of the images to be reloaded every time the page loads.  I've racked my brain and scoured the Internet for a way to do this (preferrably via javascript), but no luck. Any suggestions?


Rough Smart objects problem in Photoshop

I am using Adobe CC(2015) latest version and the behaviour of the smart objects isn't normal. When I paste a vector from Illustrator to Photoshop, the vector looks low quality or rough.   ORIGINAL  IN PHOTOSHOP   However, if I click over the smart object layer(in Photoshop)and this is opened in Illustrator, the vectors looks as the original one.   VECTOR OPENED IN ILLUSTRATOR FROM PHOTOSHOP SMART OBJECT   How can I solve this?


Hotkey to show hidden files and folders in File Open dialog?

This question is very similar to .  is also related. However, I don't want to always show them, and that's what defaults write ... AppleShowAllFiles ... does.  Rather, I want to switch it on when needed. I'm trying to open .bash_profile, so I need it now:    Linux and Gnome allow us to CTRL+H to toggle between showing and hiding hidden files. But Gnome hotkeys don't work on OS X (which is expected).  For completeness, .bash_profile does exist in the home directory:  $ ls ~/.bash_profile  /Users/jww/.bash_profile     A related question... As can be seen above, typing the filename in Finder (or is it Spotlight) search did not work. I tried to right click to get a context menu in the File Open dialog in hopes of checking a box like "show all files". And I tried the View menu looking for a "show all files" with the File Open dialog open.  Why is this hidden away somewhere? What purpose does it serve to not allow a user to easily open a file?


I am trying to add both an image and list inside a table but I face various problems. As shown in the picture, the image is above the first horizontal line and also the lists are not properly oriented, they are located at the end of the table, not in the same line with the image.  Can anybody help me with that? Thanks a lot       \begin{table}[h!]      \begin{center}      \begin{tabular}{ | c | p{5cm} | p{5cm} | }      \hline       my.Lboro & Advantages & Disadvantages \\ \hline      \includegraphics[width=0.3\textwidth, height=60mm]{images/myLboro.png}       &        \begin{itemize}       \item Accessibility       \item Up to date information       \item Fulfil students needs and wants \ldots       \end{itemize}       &        \begin{itemize}       \item Accessibility       \item Up to date information       \item Fulfil students needs and wants \ldots       \end{itemize}       \\ \hline       \end{tabular}       \caption{my.Lboro Analysis}       \label{tbl:myLboro}       \end{center}       \end{table}


It is safe to have a swap partition on the SSD?

As I'm planning to buy an SSD and replace my old mechanical hard drive, I've heard rumors that having swap partition can decrease the life of SSD. So is this true? Or can I still have a swap partition on my SSD?


Draconic Sorcerer Elemental Affinity with ongoing effects

The  Sorcerer has the following feature:  Elemental Affinity Starting at 6th level, when you Cast a Spell that deals damage of the type associated with your Draconic ancestry, you can add your Charisma modifier to one damage roll of that spell. At the same time, you can spend 1 sorcery point to gain Resistance to that damage type for 1 hour.  This reads that it would only apply to one damage roll of a spell, meaning that spells such as  and  would only benefit from the first damage roll of that spell. Is this the correct assumption? If so, would it be too strong to rule that it applies on every separate instance of damage?


I am interested to know, in which location and format are files stored when we put them in Recycle Bin? And when we delete them, where they go?


Someone removed all admin and moderator of my group. Now how can I get back this group? Note: The group has no admin or moderator now.


90s (or earlier) SciFi movie - glowing lights in chests to indicate attraction

I'm trying to figure out the name of a movie I saw on TV as a kid, in the mid-to-late 90s, in the US, in English, on daytime TV.  I remember it being kind of Starship Troopers-esque, but everyone had these glowing lights in their chests.  They glowed in different colored patterns, and I think it had something to do with whether you were attracted to someone or not (I was probably like 7 when I saw it, I didn't really understand the context of that part yet).


I don't understand how the updates on ubuntu work and I'm wondering if there is a beta for the 17.10 update. I know it's coming out mid October but I want to try it out before then.  Thanks a lot!


How to recover system when wrongly entered command?

I wrongly entered   chmod -700 /.    My entire system collapsed. All applications shutdown automatically. Then I restarted my computer. I could no longer login. What happened, and how can I fix it?


I know the subject , but I'm trying to ignore *.log files under linux and it doesn't work. I issued the command   svn propset svn:ignore "*.log" .   but when I do svn st .log files are still shown, like:  $ svn st M       myfile.log   Where am I wrong?


How can I download and install software update on my iPhone without connecting to Wi-Fi?

Please help me with installing the software update over mobile data


Difference between classical spin and quantum spin

What is the difference between classical spin and quantum spin?


Avengers: Infinity War and End Game question

At the end of Avengers: Infinity War Thanos snapped his fingers and that erased half of the life in the universe etc. But to my understanding there is no rule book with the gauntlet. He snapped his fingers because that's how he decided to channel his intentions, he mentioned at one point that with all 6 stones he could simply snap his fingers and half would cease to exist (paraphrased badly).  So why did both the Hulk and Iron Man need to do the same in Avengers: Endgame?  Almost as if snapping fingers was the only way to achieve this particular task.


Prove that $T$ has a cyclic vector iff its minimal and characteristic polynomials are the same

Let $k$ be an algebraically closed field and $V$ be a finite-dimensional $k$-vector space of dimension $n$.  Let $T:V \rightarrow V$ be a $k$-linear endomorphism of $V$. A vector $v \in V$ is called a cyclic vector for $T$ if the set of vectors $\{T^nv: n \in \mathbb{Z}, n \geqslant 0\}$ span $V$.  1 Show that if $v \in V$ is a cyclic vector, then $\{v, Tv,\cdots, T^{n-1}v\}$ form a basis for $V$.  2 If $T$ admits a cyclic vector, and $A:V\rightarrow V$ is a linear map commuting with $T$, show that there exists a polynomial $P(x) \in k[x]$ such that $A=P(T)$.  3 Show that a cyclic vector for $T$ exists if and only if the minimal polynomial of $T$ is equal to the characteristic polynomial of $T$.


I've seen that arrays work when you declare them like this:  int[] myarray = {2,4,6,8,10}; //Notice the brackets are with the type   And when you declare them like this:  int myarray[] = {2,4,6,8,10}; //Here the brackets are with the array name   So which one is the correct way of declaring an array and what are the differences (if any) between the 1st and the 2nd.  Thanks.


When there is a unique Sylow p-subgroup it is normal, does this mean that non-unique p-subgroups are not normal?

While we know that a unique Sylow p-subgroup is normal, is the converse true?  If there are multiple p-subgroups for the same p are they inherently not normal as a result?


An object reference is required for the non-static field or method or property

I am trying Action<T,T> delegate and got the following error:       An object reference is required for the non-static field, method, or   property   The event declaration looks as follows:  public event Action<string, string> FileStateProcess;   And the usage should looks like this:  if (FileStateProcess != null) {     FileStateProcess(file.FullName, temppath); }   What am I doing wrong?


If $r(t)$ is periodic and non-constant, then there exists a minimal $T$, such that : $r(t+T) = r(t)$.

Exercise :     Let $r(t)$ be a periodic and non constant function. Prove that there exists a minimum $T \in \mathbb R$ with $T>0$ such that $r(t)$ is $T$-periodic, meaning that $T$ is the fundamental period of $r(t)$.   Thoughts :  So, since $r(t)$ is periodic, that means that there exists a positive $P>0$ such that : $$r(t+P) = r(t)$$ Also, $r(t)$ is non constant, which means that : $$\frac{\mathrm{d}r(t)}{\mathrm{d}t} \neq 0, \; \; \forall t \in D_r$$ Other than these, though, I don't see how one would come up with something that shows that there exists a least positive $T$ such that $r(t) = r(t+T)$.  Any help will be greatly appreciated.


How increase filesystem size on ubuntu running inside windows

I am using ubuntu 14.04 and currently i am running it in the inside windows mode installed with Wubi. My problem is my filesystem is running on low disk space. Can i extend the filesystem size without affecting my file? How could i do that?


Can the links in the "possible vandalism: edits" flag point to the revision rather than the post

When we get the following flag:     possible vandalism: edits (auto)   We see a set of links to the posts that have been edited.  This means that to check that edit is valid we have to click the link to the post then click the link to the revisions on that post and then go back twice to get back to the flag to check the other posts.  It would be far more efficient if the links were to the revisions page rather than the post itself. It would make checking these flag much quicker.


How to store the output of `pwd` along with regular commands in history?

I want to know how I can include the current working directory (output of pwd) to the commands stored in .bash_history file.  I want this because sometimes same command is executed from different directories. It's really helpful to know from which directory a particular instance of a command was executed.


Question: Let $p$ and $q$ be distinct primes and let $n=pq$.  Prove that if $a=p+n\mathbb{Z}$ and $b=q+n\mathbb{Z}$, then $a^{q-1}+b^{p-1}=1.$  I'm not entirely convinced that the above is true.  I have applied Fermat's little theorem.  Since $p$ and $q$ are distinct primes - $a^{q-1}\equiv 1 \pmod q$ and $b^{p-1}\equiv 1 \pmod p.$  Where I am getting stuck is how to apply that second given: $a=p+n\mathbb{Z}$ and $b=q+n\mathbb{Z}.$ Added due to player3236: $a^{q-1}+b^{p-1}\equiv 1 \pmod q$ since $b^{q-1}\equiv 0\pmod q$.  Similarly for $a$ and $p$.  This shows that $a^{q-1}+b^{p-1}-1\equiv 0 \pmod {pq}$,or that $a^{q-1}+b^{p-1}-1$ is divisible by $pq$ since $p$ and $q$ are distinct primes.


How to recover: Deleted accidently important files

I've accidentally deleted today the /var/www with 2 Joomla-Homepages on it. Is there any possibility to recover all these files? I'm using PhotoRec right know, but the recovered files are named like: f3411984.html  I have not create backups, which I should have. I there a better way to recover these files.


I was installing Chrome using apt-get and after that I'm not able use command sudo apt-get install  or sudo apt-get update anything which I am doing with my package manager is not working, is always showing this error:  Reading package lists...Error!  E: Problem parsing dependency Recommends     E: Error occurred while processing foomatic-filters (NewVersion2)     E: Problem with MergeList /var/lib/dpkg/status     E: The package lists or status file could not be parsed or opened.   Can you please tell me how to fix this problem? I am using Ubuntu 11.10. I am not even able to upgrade to Ubuntu 12.04 because of this problem.


Review privilege description error in help center

The help center says the following on the review privilege:    But there are no first posts and late answers queues on MSO:


SSH through another machine at work to an external server

I'm fairly sure this will have been asked before, I have found similar questions but I do not fully understand how to apply them to my situation. So, sorry for asking again.  We have a number of servers located in a data centre which have firewall rules only allowing SSH connections to them from our work external IP. They also only accept authentication with SSH keys. Can I connect to one of these servers via another machine at work and have the key passed on from my machine (at home) for authentication?  Is this an SSH tunnel, or is that something else?  Thanks for your help.


The observer effect, how is related to death of human brain or consciousness?

Are we just a measurement device that interacts with quantum wave function/photons or something more? if not then can we die/be destroyed as observer?


Need single-shot 1 minute delay-off LED circuit

What I would like to do is have an LED turn off 1 minute after the power is turned off. The LED would be on all the time when power is on. Thus:  Turn power on: LED comes on immediately. Turn power off: LED stays on for 1 minute and then turns off.  This is to signal when someones eyes have adequately adjusted to the dark in a darkroom.  Thanks in advance.


I am not able to find concrete information about patching after install. So I have downloaded Oracle 12cR2 software from Oracle and I have successfully installed it. But now I am wondering if I need to apply the latest CPU (database and ojvm update)?  edit: So as my question state then should I apply the latest CPU (database and ojvm update) as a the first order of business after fresh install?


Book: Brain swapping, alien conspiracy, space cruise

I'm trying to find the title of a book I read sometime between 85 and 95 in German. It could have been written much earlier, and it was most likely translated from English. I think it had a "book to the movie" sticker on the cover, but all googling for the movie or book failed so far.  What I remember:   brain transplants are safe and affordable enough to rent a body for a holiday. This is achieved with a robotic surgeon removing the brain and spinal cord from the old body and reattaching all nerves in the new body. an overweight guy leaves his dominating mother to take a holiday on a space cruise, renting a new body for the trip. I think through a bribe he manages to rent the body belonging to an assassin that was held in storage while the assassin was on an assignment. At some point a small alien is revealed to be living in one of the legs. the assassin returns from the assignment and gets the body of the overweight guy to follow him onto the cruise to get his body back. He later discovers that the body contained an implant producing a permanent feeling of guilt. overall villain is a human-alien hybrid that has a robotic container attached to his spine that contains four additional brains. He owns the cruise ship and I think he tries to crash / blow it up somewhere. Though details are getting fuzzy, there.


Geometric mean never exceeds arithmetic mean

This was a mathematical induction question proposed in a textbook, and I've exhausted multiple approaches (proving RHS - LHS > 0, splitting the fraction, fractional exponents, etc.)     The geometric mean of $n$ positive numbers $a_1, a_2,\ldots,a_n$ is $\sqrt[n]{a_1a_2 \ldots a_n}$ and their arithmetic mean is $\frac{a_1+a_2+\ldots+a_n}{n}$. If $a_1, a_2,\ldots,a_n$ are $n$ positive real numbers, prove by induction that their geometric mean is always smaller than or equal to their arithmetic mean, i.e. $\sqrt[n]{a_1a_2\ldots a_n} \leq \frac{a_1+a_2+\ldots+a_n}{n}$


Derive t-distribution PDF kernel from its definition

In the Wikipedia article on the t-distribution (), they define the random variable -   $$Y = \frac{(\bar{X} - \mu)}{\frac{S}{\sqrt n}}$$  Where $\bar{X}$ is the sample mean (of a distribution that is normally distributed) and $S$ is the sample standard deviation.   Can we use this fact to derive the kernel of the t-distribution? What I normally do is try to derive the CDF $P(Y < y)$ and differentiate it with respect to $y$ to get the PDF. If we try to do this however, we get -   $$P(Y<y) = P(\bar{X} - \mu < \frac{y S}{\sqrt n})$$  Here, $\bar{X}$ is normally distributed and $S$ is inverse chi-squared. I am having a hard time making progress beyond this. The Wikipedia article I linked uses marginalization over the variance to derive it but I was wondering if we can get it from this route as well.


How to find  angle x without using calculator?  By using the trigonometric ratio formula, we can evaluate x but  in this case calculator is necessary.


Prob. 3, Sec. 3.2 in Kreyszig's Functional Analysis Book: Is the space of all polynomials of a fixed degree complete?

Let $n$ be a given natural number, and let $X$ denote the vector space consisting of the zero polynomial and of all  polynomials of degree at most  $n$, with real or complex numbers as co-efficients, and defined on a given closed interval $[a,b]$ of the real line, with the inner product defined by  $$\langle x, y \rangle \ \colon= \  \int_a^b \ x(t) \ \overline{y(t) } \ \mathrm{d} t   \   \   \ \mbox{ for all } \ x, y \in X.$$  Then is $X$ complete with respect to the norm induced by the above inner product?   I know that the space of all continuous functions is not complete in the above norm.   Let $x_m \colon= \sum_{j=0}^n \alpha_{jm} t^j$, where $t \in [a,b]$ and $m \in \mathbb{N}$,  be a Cauchy sequence in $X$. Then, given $\epsilon > 0$, there is a natural number $N = N(\epsilon)$ such that  $$\Vert x_m - x_k \Vert < \epsilon \ \ \ \mbox{ for all } \ m, k \in \mathbb{N} \ \mbox{ such that } \ m > N \ \mbox{ and } \ k > N.$$ Or,  $$\sqrt{\int_a^b \ \vert x_m(t) - x_k(t) \vert^2 \ \mathrm{d} t } < \epsilon \ \ \ \mbox{ for all } \ m, k \in \mathbb{N} \ \mbox{ such that } \ m > N \ \mbox{ and } \ k > N.$$ That is,  $$\sqrt{\int_a^b \ \left\vert \sum_{j=0}^n \left( \alpha_{jm} - \alpha_{jk} \right) \  t^j \ \right\vert^2  \ \mathrm{d} t } < \epsilon \ \ \ \mbox{ for all } \ m, k \in \mathbb{N} \ \mbox{ such that } \ m > N \ \mbox{ and } \ k > N.$$  What next?   Our aim should be to achieve the "Cauchy-ness" of the sequence $\alpha_{jm}$ of real or complex numbers, for each $j = 0, 1, \ldots, n$.   Am I right? If so, how to achieve this goal?


Why in the adiabatic equation of an ideal gas do we take  $dU= C(v)dT$ , where $C(v)$ is the specific heat capacity at constant volume ? I mean that in an adiabatic expansion or compression the Volume doesn't stay constant so why do we take $C(v)$ ?


Publishing several research papers in the same journal

In some cases a specific journal is one of the most important and relevant places for a research topic. So, is this normal and acceptable (for a pre-Ph.D. researcher) to have several papers published in that journal? I once heard from a professor that it may affect the CV in a destructive way.   If I have several papers published in the same journal, will people think that my papers were published not because they were good, but because I was somehow able to bypass the peer review process?


I need to design an onscreen keyboard for a touch device and wondering if there are any standards to follow especially pertaining to key sizes?


How to use several adjectives afterwards

While doing an English test I've found this question :     A ___________ lives in that house.         fat, small man   small, man fat   man, fat small   small, fat man        Could someone give me an explanation of what's the right answer, and more importantly why?  Is there a difference between British and American English in this case?


Why are drag and kinetic energy proportional to velocity squared?

For example, it takes a car four times the kinetic energy to travel the same distance at twice the speed, which quadruples the drag experienced by the car. This observation is described by the standard equations: Drag  =  0.5 (Velocity2  x  Air Density  x  Surface Area  x  Coefficient of Drag) K.E.  =  0.5mv2 I'd really appreciate it if someone could critique a new explanation based on Newtons second law (force = ma), or confirm if this explanation is correct: For a car travelling at a constant velocity. The force from the engine pushing the car forwards (i.e. Force FORWARD = ma = m/dt x dv), equals mass of air each second (m/dt) that the car travels through and accelerates away from it at a given velocity (dv). The more aerodynamic cars will have a lower 'dv'. Force FORWARD = ma = m x dv/dt  =  m/dt x dv Just to be clear, note that 'm' and 'v' are NOT not the mass or the velocity of the car. This action generates an equal and opposite force, called drag. At constant speed, so no acceleration, the forward force will equal the drag, which is the force required to push the air out of the car's path. Force FORWARD   =   Force DRAG  If the car's speed doubles (x2); then the forward force, drag and kinetic energy required all quadruple (x4), as described by their standard equations above. The explanation for this quadrupling is: (i) The car will travel through twice the mass of air each second (2x ‘m/dt’). (ii) As the car's momentum has doubled, the car will accelerate this air travelled through to twice the velocity as before (2x ‘dv’). The combined effect is to quadruple the total force for drag each second; (i.e. 4x Force DRAG = 2m/dt x 2dv).  In addition, force and energy are proportional for a given distance travelled by the car, based on their respective definitions: Force   =   1 kg m /s2      =   1 N Energy  =   1 kg m2 /s2     =   1 J Given that the distance travelled by the car has not changed, but the force required to push the car forwards and drag have both quadrupled (x4), therefore, the kinetic energy required will also quadruple (KE x 4). This is why it takes four times the kinetic energy and drag to travel the same distance at twice the speed; And why kinetic energy and drag are proportional to velocity2. Is this correct?  Thanks!


I tried approach by line, parabola, polar coordinates, double limit. I do not know any other way to determine whether this limit exists or not.


Why does $\frac{1}{r}\frac{dr}{d\theta} = \cot \psi$?

In the discussion of linear fractional equations in Birkhoff and Rota's Ordinary Differential Equations, the authors assert that if we convert a DE of the form $y' = F\left(\frac{y}{x}\right)$ to polar coordinates, then we have \begin{align} \frac{1}{r}\frac{dr}{d\theta} = \cot \psi, \end{align} where $\psi = \gamma - \theta$, with $\gamma$ being the tangent direction and $\theta$ the radial direction.  I'm afraid this has me entirely buffaloed -- why on earth is this true?  I have neither an analytic nor geometric intuition as to how this could possibly be.  I'm sure there's some elementaryish fact about $\frac{dr}{d\theta}$ which makes the answer obvious, but I have no clue what said fact is.  I do note that  \begin{align} \frac{dy}{d\theta} &= r\cos\theta + \frac{dr}{d\theta}\sin\theta\Rightarrow\\ \frac{dr}{d\theta} & = \frac{dy}{d\theta}\csc\theta - r\cot\theta\Rightarrow\\ \frac{1}{r}\frac{dr}{d\theta} & = \frac{1}{y}\frac{dy}{d\theta} - \cot\theta,  \end{align} but this is as close as I can come to getting a cotangent anywhere near the expression (and, of course, $\theta \neq \psi$ in general).  What gives?


Where is the suspend/hibernate button in GNOME Shell?

In 17.04 I could suspend\hibernate from the power off menu button.  I can't find how to do this in Ubuntu 17.10 GNOME Shell.


Is there any way to specify a "TO DO" in LaTeX?

I'm writing my degree thesis in LaTeX and I have some chapters and sections which I didn't write yet.   Is there any way to put a tag to specify that there is a TO DO there so I remember to fill it ? (I mean something similar to @TODO in Java comments)  It would be great if LaTeX compiler raises a warning in the logs if it has found that tag.


Prove a property of dot product in complex numbers

Let a matrix A be an arbitrary matrix of size n by n in $\mathbb{C}$. Prove that for vectors $x, y \in \mathbb{C}$, the dot product of $<Ax, y>=<x, \bar{A^T}y>$ (note that the dot product is expressed as "<>", and $\bar{A^T}$ is the conjugate of the transpose). I think we can use the fact that in general$<x,y>=x^T\bar y$. And I also know that $\bar{Zy}=\bar Z \bar y$, where $x, y$ are vectors, and $Z$ is a matrix (of course this only works in complex numbers). Can someone show the steps to proving this? Thanks.


small lines when printing to PDF from Illustrator

I have an Illustrator file that's behaving strangely when I print it to PDF. Basically, it adds small lines around shapes; I included a zoomed-in screenshot.    If I save the file as PDF, the lines don't appear but then the file itself is huge: 30MB. Has anyone seen this issue and if so, how do you solve it?  Thanks.


Is it possible to create a responsive design in SharePoint 2013

We are upgrading to SharePoint 2013 and we want to make a new design to take advantage of the new features.  But is it possible to create a responsive design in SharePoint 2013? (In both 2007 and 2010 it was almost impossible)


Computing the Gauss curvature of the hyperbolic paraboloid

Let $S = \{(x, y, z) \in \Bbb{R}^3 \ | \ z = x^2 - y^2\}$ be the hyperbolic paraboloid. Our aim is to compute the Gauss curvature at the origin. I thought I knew how to do this, but I keep getting this wrong. Any hints towards the right direction will be the most appreciated.  I proceeded as follows:  We know that the hyperbolic paraboloid is the graphic of a function $f(x, y) = x^2 - y^2$, hence orientable with unit normal field $$ N = \frac{1}{\sqrt{1+|\nabla f|^2}}(-f_x, -f_y, 1) $$ where the subindex denotes partial differentiation. Then, for our function,  $$ N(x, y, z) = \frac{1}{\sqrt{1+4(x^2 + y^2)}}(-2x, 2y, 1). $$ I then tried to compute the jacobian matrix of N at the point $(x, y, z)$, which gives us $(dN)_{(x, y, z)}$. At the origin, we have  $$ (dN)_{(0, 0, 0)} =  \begin{bmatrix} -2 & 0 & 0 \\ 0 & 2 & 0 \\ 0 & 0 & 0 \end{bmatrix} $$ what gives zero Gauss curvature since the determinant of this matrix is zero. However, I was supposed to get a negative value. What am I doing wrong?  PS: I chacked my computations with WolframAlpha.  Thanks in advance.


E: Could not open lock file /var/lib/dpkg/lock - open (13: Permission denied)

When I try to install a new app (a code editor in this case, brackets) I click on install but it doesn't work. When I want to install new updates available from Ubuntu Software it does this: I click on install, then it asks me for the admin password, I write it, the install bar gets full and stays like this for ever. No installation.  Please what could the problem be? I read other topics about this same problem but it doesn't seem to go away


which one is correct?      1.I have bought three nails.    2.I have bought three pieces of nail.   is nail a material or common noun?  arm a proper noun or common noun?


Using reflection to instantiate a class without running its constructor

Is it possible to do this?  I have a class with validation logic in the constructor. For general use I want to enforce this constructor.  However, when deserializing the so said class, I want to be able to bypass that validation logic and simply reserve the memory space without running any construction routine (like malloc in c++).The properties will then be mapped manually using reflection, after the object has been instantiated.  Is this possible in C#?


I would like to log session with byobu. I wen through the configuration files but I could not see anything like log session etc.  I want byobu to log my session as soon as launch it with date. :)


What happens if a goalkeeper catches the ball whilst their body/legs are still in the box, but the ball is just out of the box?

I have always wondered this.  Is a goalkeeper handball determined by where the ball actually is, or where the goalkeepers body is positioned at the point of contact?


I have Fedora 20 installed in my laptop. I want to move on from Fedora 20 to Ubuntu 18.04.  Is it necessary to boot to windows first or can I directly boot Ubuntu 18.04 on my Fedora 20 by USB boot?


What does it mean when `ls` shows a numeric user id?

I'm fairly new to the ubuntu system. We have an Ubuntu server where we host our WordPress sites, and I have seen a lot of 1002 users when I do the ls -lh command inside a directory, like:  -rw-rw-r-- 1 1002 www-data 3.0K May 7 2014 wp-login.php   What is, or who is user 1002?


Hi I ran the following command   sudo apt-get upgrade   However I'm getting the following      You might want to run 'apt-get -f install' to correct these. The following packages have unmet dependencies:  mysql-server-5.5 : Depends: mysql-server-core-5.5 (= 5.5.28-0ubuntu0.12.04.3) but 5.5.35-0ubuntu0.12.04.2 is installed  E: Unmet dependencies. Try using -f.   I came across the following  but not sure how I should go about applying it to my situation.  Any help would be appreciated


Why isn't this a well ordering of $\{A\subseteq\mathbb N\mid A\text{ is infinite}\}$?

So, to explain the title, I'm referring to the necessity of the axiom of choice in the existence of a well ordering on reals, or any uncountable set.  Now, while tweaking some sets, I came across this :  We start with the natural numbers, $N$. We take the power set of the naturals, $P(N)$.  Then we remove all the finite subsets of $N$ from $P(N)$. Let us call this new set $S$. This set is the set of all infinite subsets of $N$.  It is easy to show that $S$ has uncountable cardinality, same as that of real numbers. This is because the removal of finite subsets only removes a countable number of elements. (Haven't posted this deduction, for it is very easy, but I may post it if it is not so evident)  Now, we seek to find an ordering on the set $S$. Every set in this set is an infinite subset of natural numbers, so each of these sets are well ordered by the natural ordering of $N$.  Taking any two sets in $S$, say $A$, and $B$, we seek to order them by checking their elements lexicographically. We compare the first two elements in $A$, and $B$. Let them be $a_1$, and $b_1$ respectively. If $a_1 = b_1$, then we move on to the second elements in the sets, $a_2$, and $b_2$, and so on. If, at any point, $a_n < b_n$, then $A < B$, or if $b_n < a_n$, then $B < A$.  This order seems to be a well ordering of the uncountable infinity of reals. I don't seem to have invoked the axiom of choice anywhere in the construction of this set $S$.  So, why isn't this a well ordering on the uncountable of reals?


What is the total propagation delay of the ripple adder?

Assume 4 full adders are cascaded.   Propagation delay of XOR gate = 20 ns, AND gate = 15 ns and OR gate = 10 ns.  What is the total propagation delay of the ripple adder, if the output is stabilized ?    My try :   When 4 full adders are cascaded, then carry has to ripple upto the last adder.  After the output is stabilized, I can say total propagation delay = 3*45 + 40 = 175 ns.  My try is based on the assumption of below circuits.  Here, 1st XOR and 1st AND gate can be done parallely and 2nd XOR and 2nd AND gate can be done parallely.


Does an Animagus's animal form change along with their Patronus?

In the two examples shown of an Animagus capable of casting a corporeal Patronus (Minerva McGonagall and James Potter) both had the same animal as their Patronus and as their Animagus animal.  Now, it is also shown that extreme circumstances can change one's Patronus. I think the only example of this was Tonks, which turned from a jackrabbit into a wolf in response for her love of Lupin.  If Tonks (or any other wizard who had their Patronus change) had been an animagus, would her animagus have changed as well?


How to turn off password requirement when awakening from suspend-mode?

I have turned off the password requirement for my Ubuntu 20.04, but whenever I suspend my device and turn it on again, I am still asked for a password. How can I turn this option off in Ubuntu 20.04?


Are there mobile apps for Stack Overflow?

I am used to using my smart phone to browse Stack Overflow with a web browser, but I feel that that's not a very good solution. Now I want to use a mobile app to browse SO.  Is there a mobile app for Stack Overflow, or plans to develop one? Third-party apps (both Android and iOS) would be fine for me.


How do I replace oven insulation that has been soiled by mice and smells bad?

We've had mice work their way into the oven insulation of our standalone range and now it stinks when we turn the oven on.  Looking around on the web suggests that replacing the oven is the most common solution, but that seems extreme!  Any suggestions?  (In this case the oven is a "Viking Professional" (bottom of the line) 4 burner + oven freestanding range. I haven't yet been able to pull it out enough to check if it has removable panels or been able to find a manual online.)  I'm guessing the answer will be something like:   locate the manual for your appliance remove access panels remove insulation while being careful about ?? remove insulation that is "stuck" by doing ?? replace with new insulation from ?? put it all back together and test as follows in general be careful of ??   And, perhaps this is too specific to the brand of appliance? It would be useful to know which brands are more amenable to DIY repairs of this type than others.


Is there a non-transphobic alternative to "he or she"?

For instance, "A politician must be able to think quickly on the spot. He or she must also have no qualms about lying."  I know some people who use "they", but as that both sounds and is ungrammatical, I'm wondering if there is any other concise and non-awkward alternative.  Edit:  Apparently many do consider "they" as correct. This surprised me, because I know someone who actually wrote a grammar book, who told me in no uncertain terms that "they" could not be used (in fact, I'd asked them - ha! - this question before I posted it here). And a quick look online found legitimate sources advocating both positions. I suppose it's one of those issues, such as whether the previous sentence was incorrect for beginning with a conjunction, where it really just depends who you ask. Regardless, to me personally, "they" in the above example sounds clunky at best and incorrect at worst. So I suppose my question can be rephrased as, 'is there any alternative to 'he or she', other than 'they'?"  Secondly, to whoever tagged this as "politically-correct": acknowledging the existence of genderqueer or transgender people isn't a political issue at all, until those made uncomfortable by people unlike them make it one. Trying to avoid excluding and thus unconsciously discriminating against a group of people in your writing isn't born out of a need to be 'politically correct' - it's born out of basic human decency.  Finally, yes, in the example above, I could use a comma and avoid the need for a pronoun at all - but the question I'm asking applies to instances where one may not want to do so (i.e. the sentences are long and stringy enough as it is).


"I remember the day where" vs. "I remember the day when"

What is the difference between "I remember the day where..." and "I remember the day when..."?    I think both are used in both written and spoken English. Can we say that "when" makes more sense when we are talking about a specific point in time?


Is $\text{rank} (AA^*)=\text{rank}(A)$ for all nonsquare matrices?

If $A$ is a $m\times n$ type matrix with $m\geq n$ then  $$ rank (A^*A)=rank (A). $$ Is maybe also true in general that  $$ rank (A^*A)=rank (A) ? $$ Thanks  Edit.  My question is different from the question about $rank(A^TA)=rank A$, because concerns complex conjugate transposed matrice instead of transposed.


What's wrong with the code? No matter the user input, team 1 will win the game

import java.util.*; import java.util.Random;  public class Playoffs {   public static Scanner scan = new Scanner(System.in);    public static void main(String [] args)   {        boolean validNumber;     int game1;      System.out.print("What is the % chance that team 1 will win the game?");      do{       game1 = scan.nextInt();       validNumber = game1 >= 0 && game1 <=100;        if(!validNumber){         System.out.println("INVALID NUMBER ENTERED: NOT BETWEEN 0 AND 100");         System.out.print("Enter a valid number between 0 and 100: ");       }     }while(!validNumber);     System.out.println("Team 1 has a " + game1 + "% chance of winning.");   The code below should generate a random number between 0 (inclusive) and 100 (exclusive), stating that if the random number is less than the percentage the user input, team 1 will win, and team 2 should win if the random number is greater than the percentage entered, but it always comes out that team 1 wins      Random rand = new Random(100);     int randomNumber = rand.nextInt();     int oneGame = simulateOneGame(game1, randomNumber);      if(oneGame == 1){       System.out.println("\nTeam 1 has won the game");     }else if(oneGame == 0){       System.out.println("\nTeam 2 has won the game");     }   }    public static int simulateOneGame(int game1, int randomNumber)   {     int result=0;     if (randomNumber < game1) {       result += 1;     } else if(randomNumber > game1){       result += 0;     }     return result;   }  }


What is Generated Mapping and UV Mapping? And what is the difference?

Well, basically that's it. What are this texture mapping modes? Is there pros and cons of each one?


How to find right ND filter for my panasonic lens Lens LUMIX G VARIO 12-60mm / F3.5-5.6 ASPH. / POWER O.I.S.?

I have a panasonic G85 with Lens LUMIX G VARIO 12-60mm / F3.5-5.6 ASPH. / POWER O.I.S. How do I find the right ND filter for this lens? I'm new to photography and really confused about this.   Closest Focusing Distance0.20m / 0.66ft (Wide), 0.25m / 0.82ft (Tele) Maximum magnification Approx. 0.27x / 0.54x (35mm camera equivalent) Diagonal Angle of View84.05°(Wide) to 20.44°(Tele)  General Filter Sizeφ58mm / 2.3inchMax.  Diameterφ66.0mm / 2.6inch


Restricting Org Wide Email Addresses based on profile in Apex?

I have a class marked 'With Sharing' and a simple method to get all org wide emails to populate in a picklist on my page:  public String getOrgEmails(){     List<OrgWideEmailAddress> orgWideEmails = new List<OrgWideEmailAddress>();      orgWideEmails = [SELECT Id, Address, DisplayName FROM OrgWideEmailAddress LIMIT 50000];      return JSON.serialize(orgWideEmails); }   I had thought that when users set up org wide emails, and specified profiles who could access them, the query would only return org wide emails a user was profiled to have access to.   This is not the case. The query just returns all org wide emails. But, the org wide email address object is very limited and doesn't tell you what profiles have access to it.   Is there any way to actually limit the org wide emails returned by if the executing user has access to it based on profile permissions on the org wide email.   Salesforce is obviously capable of doing this check, which is why they let you set that up. But I cannot see how we are able to do this check in apex.


I need to include '(r)' in my document, but it defaults to the registered trademark sign, ® .   How can I override this?


Why do I have to click twice to submit a question when Stack Exchange's automated question review has no advice to show?

This is terrible . I understand that the motivation behind "Review your question" is quality control, but if there is nothing for me to review, why can't the question be submitted in a single click?  Instead the page jumps back, to draw my attention to possibly this:    But it doesn't stand out in the UI, and if you didn't read that the button said "Review your question", it's hard to see why the page just jarringly jumped back instead of posting the question.  Is it really important for me to know that the automated system didn't find any way to improve my question?  Does Stack Exchange have metrics to see how often the question passes the quality check in the first go?  To add a minor point, as a veteran Stack Exchange user, the system doesn't have any reviews most of the time (in fact, the only time it had one is today while posting this question where it reminded me that one of feature-request, bug, .. tags were required).


Using a 'corporate author' in the "author" field of a bibliographic entry (spelling out the name in full)

I want to list a company name in the author field of a bibliographic entry:  @book{CUDA,   author    = {NVIDIA Corporation},   title     = {NVIDIA CUDA Compute Unified Device Architecture Programming Guide},   publisher = {NVIDIA Corporation},   year      = {2007} }   But the entry keeps showing up "N. Corporation".  Is there a way to get the full author name to show up?  I'm currently using the siam BibTEX style.


Prove Borel sigma-algebra translation invariant

Can anyone explain: Let $B$ be a Borel set and $B + a = \{ x + a : x \in B\}$. Why is $B + a$ a Borel set?  I think I have to use some good set principle but not sure how to complete the proof.


Can I live view my Nikon D3200 via laptop/ tablet etc?

I am wanting to take self portraits using my Nikon D3200 and was wondering is there a way I can stream the live view through a laptop, tablet or some other screen?   I want to have the screen facing me so I can see what the picture will look like before I capture it so it's not a case of clicking and hoping.  I have an AV out (from camera) to USB lead and also an AV out (from camera) to the yellow and white lead  Hope that makes sense  Thanks


How do I set a featured image (thumbnail) by image URL when using wp_insert_post()?

While looking through the , I noticed that there's no parameter in the array it requires which will allow me to set the 'Featured Image' for a post, displayed as the  in my theme.   I have looked into functions like , as suggested by Mr. Bennett, but this seems to be a relatively new addition to WordPress itself and the WordPress codex. As such, there aren't any sources that I can find which explain how the $thumbnail_id parameter should be acquired and supplied. If this really is the function to use, in what way could I provide it with a valid $thumbnail_id parameter when all I have is an image URL?  Thanks in advance!


Number of distinct strings reachable by at most 2 swaps

We're given a string $S$ with $N$ characters (the characters can be repeated). We can swap $2$ positions of two characters to obtain another string, and we can swap at most twice. How to find the number of distinct strings reachable by at most two swaps?


Does your previous university’s reputation matter when applying for a PhD?

I have been applying to PhD programs for the past 2+ years and keep getting rejected. I have pretty good degrees that I worked hard for from good universities (not the top unis).   For the past year I’ve been doing everything I could think of to improve my CV; working for free as a research assistant at a research institute, publishing, attending seminars and conferences, etc.  I always thought that all applicants were treated equally and were judged only by their grades, personal statement and CV. However, I just got my 15th rejection letter, and the university was “kind” enough to tell me that I was rejected because I didn’t meet their entry requirements, specifically, that the universities where I did my Bsc and MSc don’t have a good enough reputation for my application to be considered.  I have been told by academics in the past that potential PhD candidates aren’t judged using this criterion. So my question is, are Phd applications one of those things where people are told that everyone has an equal opportunity while the reality is wildly different? Because I would like to know if I’m wasting my time applying and putting myself through all this stress unnecessarily.


During my recent work I encountered a weird type of differential equation containing scalar factors. In order to understand them better I thought it would make sense to look at a simpler example like:  $$ \dot x(t) = x(2t)$$  How does one solve this equation? Does it even have a solution? It seems kinda related to  which I am not familiar with.


The iOS beta app instantly crashes when starting it.  I am running iOS 9.1 with version 1.4.0.247 of the app.  It might be related to  since that issue happens around the same time.  Can this be fixed please?


How to get the asymptotic expression of DOS near Van Hove singularity

For the simplest example, 2D square lattice tight binding model gives the energy band as $$\varepsilon_k=-2t(\cos k_x+\cos k_y) \, .$$ We know that $\vec{k}=(0,\pi)$ and related momentum points are saddle points which give $|\nabla_k \varepsilon_k|=0$ and thus some kind of singularity in density of state (DOS) since $$\rho(\varepsilon)\propto \int_{\varepsilon=\text{const}} \frac{d S}{|\nabla_k \varepsilon_k|} \, .$$ How can I get the $\ln$ divergence for DOS near $\varepsilon=0$? Should I only care about those singularity points and omit the integral from normal parts and do Taylor expansion near those saddle points? Why are points like $(\pi/2,-\pi/2)$ not called Van Hove points when those points are also lie in the $\varepsilon=0$ line and give $|\nabla_k \varepsilon_k|=0$? Consider a dispersion relation in 1D like $$\varepsilon_k = \left\{ \begin{array}{ll} 0 & |k| \le 1 \\ |k|-1 & |k| > 1 \, . \end{array} \right.$$ What kind of divergence near $\epsilon=0$? It seems that the DOS for all $\varepsilon>0$ is a constant and suddenly goes to infinity when $\varepsilon$ is fine tuning to zero. Since there is an integral on the constant energy surface in the DOS formula, what if the constant energy surface is not closed and thus an infinite one? As another 2D  example, $$\varepsilon_k=v_xk_x+v_yk_y \, .$$ The isoenergy surface will be plane extended to infinite and thus ill-defined in the integral $\int dS$.  Some one may argue that this kind of Hamiltonian must come from effective theory which is only valid for low energy and thus has a valid region beyond which the dispersion relation doesn't work. Well, if I only care about the divergent behavior and don't want to go further to the 'real' dispersion which is  hard to manipulate (perhaps no analytical expression at all). Can I get the divergent information only from the linear dispersion? Should I give $k$ region a cut off or do something else?


I have looked every pages, links, forums etc. It is a standalone application.  I add all paths that I can find to the PATHS and PYTHONPATH is here:  C:\OSGeo4W64\apps\qgis-dev\python C:\OSGeo4W64\apps\qgis-dev\python\plugins C:\OSGeo4W64\apps\qgis-dev\python\qgis   However it doesn't work and gives the same error for 12 days...  from qgis.core import * from qgis.gui import * from qgis.utils import * from PyQt5.QtCore import * from PyQt5.QtGui import *  app = QgsApplication([], True) path = "C:/OSGeo4W64/apps/qgis-dev" app.setPrefixPath(path, True) app.initQgis()  canvas = QgsMapCanvas() title = "PyQGIS Standalone Application Example" canvas.setWindowTitle(title) canvas.setCanvasColor(Qt.white)  layer_info = 'LineString?crs=epsg:4326' layer = QgsVectorLayer(layer_info, 'MyLine', "memory") pr = layer.dataProvider() linstr = QgsFeature() wkt = "LINESTRING (1 1, 10 15, 40 35)" geom = QgsGeometry.fromWkt(wkt) linstr.setGeometry(geom) pr.addFeatures([linstr]) layer.updateExtents() QgsProject.instance().addMapLayer(layer) canvas.setExtent(layer.extent()) canvas.setLayers([layer]) canvas.zoomToFullExtent() canvas.show() exitcode = app.exec_() # QgsApplication.exitQgis() sys.exit(exitcode)   Here is the error:  Traceback (most recent call last):   File "C:/Users/Mustafa Uçar/Desktop/sil.py", line 1, in <module>     from qgis import _core   File "C:\OSGeo4W64\apps\qgis-dev\python\qgis\__init__.py", line 72, in <module>     from qgis.core import QgsFeature, QgsGeometry   File "C:\OSGeo4W64\apps\qgis-dev\python\qgis\core\__init__.py", line 34, in <module>     from qgis._core import * ImportError: DLL load failed: Specified module could not found.   System information:  QGIS 2.99 - Python 3.6 - Win10*64


Free Body Diagram for a Body on a Smooth Inclined Plane

Consider a body of mass $m$ on a smooth inclined plane with the normal force and weight labelled as shown:  Now, usually when the forces are broken into its components, we get an FBD like this:  From this we can obtain the equation: $$ \Sigma F_\perp = 0\quad \implies\quad N = mg\cos(\theta) \tag1$$ However, I tried resolving the forces along the x and y axes and obtained a diagram like this:  But this time I got a different equation: $$ N\cos(\theta) = mg \tag2$$ Clearly, equation (1) and (2) aren't the same. So what am I missing here?


How to make lubuntu (LXDE) terminal support Arabic or Persian language?

In my lubuntu machine terminal the Arabic letters are being displayed from left-to-right and they are not bound together (Altogether on a text editor everything is working correctly).  The reason for wanting terminal to display Arabic is that I'm trying to develop a Python program which uses graphical elements like TextBox (actually Entry in tkinter). I found different modules to output strings consisting of Arabic letters in a correct form but while the user is typing in the Textbox it displays the same way as in my terminal (from left to right and with isolated individual letters).   How can I get these scripts to display correctly?


If $x$ divides $z$, $y$ divides $z$ and $x$ and $y$ are relatively prime, then $xy$ divides $z$.

I've been stuck on this for far too long, but it isn't proved in my lecture notes so it's supposed to be elementary...  Let $x, y, z$ be integers such that $x$ divides $z$, $y$ divides $z$ and $x$ and $y$ are relatively prime, then $xy$ divides $z$.  Thanks a lot !


Confusing edit behavior: Is it a bug or a feature?

I sometimes bump into questions which have an (1) next to the edit link. If I click on it I am presented with the review screen.  I can either click accept or reject but whatever I do the suggested edit still needs some more accepts to pass.  If there is no suggested edit however I can edit a question without the need of reviewing.  So my question is that this behavior is a bug or a feature?  Sometimes I read questions and they have formatting issues, bad grammar etc... and I click on edit and correct the problem(s). But in case of a suggested edit this feature does not work.  Note: I have sufficient privileges to edit a post.


Apache's Digest Authentication md5(user:realm:password) is not the hash inside .htdigest file

on Apache's docs site:    They say that the hash of the password used for Digest Authentication created with the htdigest utility:  $ htdigest -c ./.htdigest "A Realm" user Adding password for user in realm A Realm. New password: Re-type new password: $ cat ./.htdigest user:A Realm:879af2190fce9012039001fecbb23412   879af2190fce9012039001fecbb23412 = md5(user:A Realm:password). However, if I type:  $ echo "user:A Realm:password" | md5sum e77ed25bc7d1fe5ffe9f827346b2cd7b    -   I get another hash, which is not the one inside ./.htdigest.  How then Apache computes the MD5 hash inside ./.htdigest when I create the file with htdigest?


what's the difference between bash my_script and source my_script

Both of two lines below seems to execute my_script. What's the difference between the two processes?  $ bash my_script $ source my_script


How to handle materials in an Entity/Component system

My E/C implementation is the basic one where Entities are just ID's, Components are data and Systems act on the Data. Right now I'm having trouble with object materials and rendering in general. For simple objetcs I have a ModelComponent, tied to a RenderSystem, ModelComponent has the vertex buffer ids that the render system uses. A simple MaterialComponent would probably have color or specular strenght, etc, but I wanted it to be flexible enough to allow for more than one render pass and general "effects" that are not as easy as a simple variable in the MaterialComponent.  Trying to solve these problems I came up with two solutions:  1 - Super-generic Material Component  Something like this:  struct Material : public Component {     ShaderData* shader;     std::vector<std::pair<std::string, boost::any>> uniforms;     [...] };   and in the render system I would loop and pass the uniforms to the shader. I suppose this would be slow, but fast enough for my purposes.  2 - Another layer of abstraction, MaterialData  Having a class to wrap specific materials, that could be inherited by whatever specialized  material, the base class would have something like void set_shader_constants(ShaderData* d) but the implementation is up to each class, and the MaterialComponent would have a pointer to a MaterialData object.  I'm not sure which approach I would prefer, but neither of these touch the subject of multiple passes, or other complex rendering techniques.  Any idea on how to accomplish this?


Apps fail to launch even when clicked on

Multiple apps fail to launch from Ubuntu 17.10. When I click on some of the apps  they do not launch.  i tried doing  sudo apt install unity unity --reset-icons   when i open a application for example steam), this comes up  tar: This does not look like a tar archive xz: (stdin): File format not recognized tar: Child returned status 1 tar: Error is not recoverable: exiting now find: ‘/home/jitu/.steam/ubuntu12_32/steam-runtime’: No such file or directory


Simulate the critical values of Dickey-Fuller test statistic with R

I am trying to replicate (approximately) the results of the unit root tests described in chapter 17 of Hamilton's book. For the case   \begin{equation} y_{t}=y_{t-1}+\varepsilon_{t},\ \varepsilon_{t}\sim \mathcal{N}(0,1) \end{equation}  with the statistic   \begin{equation} t=\frac{\hat{\rho}-1}{\hat{\sigma}_{\hat{\rho}}} \end{equation}  where $\hat{\rho}$ is the usual OLS estimate and $\hat{\sigma}_{\hat{\rho}}$ its standard error.  My question is:   Is my R code correct? My results are not close to the tabulated values, for example   The critical values of the test with $T=25$ and $\alpha=0.05$ are -2.26 and 2.16. But I get -0.1433872 and 3.2984347   The function simulates $R$ times a random walk of size $T$ and calculates the least squares estimator for each, and their standard error. The resulting distribution should be similar to the tabulated values commonly used.      case1<-function(nob,R){       R<-1000       beta.hat<-statistic<-sd.beta<-c()       for (r in 1:R){           y<-error<-vector()           y[1]<-0           nob<-25           for (i in 2:nob){             y[i]<-y[i-1]+rnorm(1,0,1)           }           res<-lm(y[2:nob]~Hmisc::Lag(y)[2:nob])           res.sum <- summary(res)           statistic[r] <- (res.sum$coefficients[2, 1]-1)/res.sum$coefficients[2,2]       }       statistic     }     data<-case1(nob=25,R=10000)     quantile(data, probs=c(0.025,0.975))     hist(data)   Thanks in advance.


I tried to install Ubuntu onto a USB stick but it doesn't install all of the files. I don't see the Ubuntu logo appearing in my USB drive, only an ideogram of a sheet with a folded corner and it will be labeled Ubuntu. I've read to install LiLi USB Creator on a stick with either FAT or FAT32 partition which I read only worked on 4GB sticks and on 34bit computers with 2.0 USB ports. I tried it with exFAT and FAT32 partitions and the last time I tried downloading Ubuntu onto a stick it completed 99% of the download and then quit. What exactly do I need to do to get an Ubuntu system fully downloaded onto a thumb drive and loaded onto 64bit laptop?


I recently install ubuntu 18.4 and i tried to install Gnome Shell Extension in Firefox, the extension has been install, but show this 'Although GNOME Shell integration extension is running, native host connector is not detected. Refer documentation for instructions about installing connector.'. I try to install same extension in chrome and show the same error, and in Chromium the same error  i install Ubuntu in 2 PCs and the error to persist


How do I take multiple photos of an open area that has moving people in it and eliminate them through a photo stacking process?  Thanks


Electromagnetic radiation transmits energy to the sail by reflection or absorption. Does it mean electromagnetic radiation also loses velocity and gain mass in the process?


Ubuntu 14.04 sudo: unable to resolve host Cricketpunk

i am new to ubuntu and recently tried changing my hostname and have probably messed up something,and have trouble fixing it.  Whenever i give command like     get sdu       sudo apt-get install g++ (some command using sudo)    sudo: unable to resolve host Cricketpunk    shows up,after 4 seconds of wait.After reading few questions,i tried changing something in /etc/hostname,but it says access denied when i try opening that file  i Cannot boot into recovery mode due to soome bios fault   I need help on how to achieve sudo rights using live flash drive containing ubuntu.  Any help would be much appreciated. Have a good day :)


Reduction formula for $\int \tan^n x dx$

Reduction formula for  $$I_n = \int \tan^n x dx$$     Let $u(x) = \tan^{n-2} x \qquad \qquad v^{'}(x) = \tan^2 x$   Integrating by parts  $$I_n = (\tan x - x)(\tan^{n-2} x) - \int (\tan(x) - x)(n-2)(\tan^{n - 3} x + \tan^{n- 1} x) dx \tag{0}$$  Let the second integral be $J$,  After expanding and simplifying I get,  $$J = (n-2)I_{n-2} + (n-2)I_n - (n-2)\int x\tan^{n-3} x + x\tan^{n-1} dx \tag{1}$$  Let $w(x) = \tan^n x \qquad \qquad z^{'}(x) = 1$  Integrating $I_n$ again by parts,  $$I_n = x\tan^n x - n\int x\tan^{n+1} x  + x\tan^{n-1} x dx$$  For $I_{n-2}$,  $$(n-2)\int x\tan^{n-3} x + x\tan^{n-1} dx = x\tan^{n-2} x - I_{n-2}$$  Substituting this in $(1)$  $$J = I_{n-2}(n-1) + I_n(n-2) - x\tan^{n-2} x $$  Substituting this in $(0)$,   we get,  $$I_{n} = {\tan^{n-1} x \over n-1} - I_{n-2}$$.  Is this correct ? I know the final answer is correct but is the method correct ? looks a bit circular to me.


When I execute my code in eclipse maven environment, I am getting this error, as I am new to java don't know how to proceed further, any solution please.    Exception in thread "main" cascading.flow.FlowException: unhandled exception     at cascading.flow.BaseFlow.complete(BaseFlow.java:954)     at com.bitwiseglobal.engine.integration.BHSRuntime.execute(BHSRuntime.java:170)     at com.bitwiseglobal.bhse.utilities.BHSExecution.execute(BHSExecution.java:50)     at com.bitwiseglobal.bhse.utilities.BHSExecution.main(BHSExecution.java:29) Caused by: java.lang.NullPointerException     at java.lang.ProcessBuilder.start(ProcessBuilder.java:1010)     at org.apache.hadoop.util.Shell.runCommand(Shell.java:482)     at org.apache.hadoop.util.Shell.run(Shell.java:455)     at org.apache.hadoop.util.Shell$ShellCommandExecutor.execute(Shell.java:715)     at org.apache.hadoop.util.Shell.execCommand(Shell.java:808)     at org.apache.hadoop.util.Shell.execCommand(Shell.java:791)     at org.apache.hadoop.fs.RawLocalFileSystem.setPermission(RawLocalFileSystem.java:656)     at org.apache.hadoop.fs.RawLocalFileSystem.mkdirs(RawLocalFileSystem.java:444)     at org.apache.hadoop.fs.FilterFileSystem.mkdirs(FilterFileSystem.java:293)     at org.apache.hadoop.mapreduce.JobSubmissionFiles.getStagingDir(JobSubmissionFiles.java:133)     at org.apache.hadoop.mapreduce.JobSubmitter.submitJobInternal(JobSubmitter.java:437)     at org.apache.hadoop.mapreduce.Job$10.run(Job.java:1296)     at org.apache.hadoop.mapreduce.Job$10.run(Job.java:1293)     at java.security.AccessController.doPrivileged(Native Method)     at javax.security.auth.Subject.doAs(Subject.java:415)     at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1628)     at org.apache.hadoop.mapreduce.Job.submit(Job.java:1293)     at org.apache.hadoop.mapred.JobClient$1.run(JobClient.java:562)     at org.apache.hadoop.mapred.JobClient$1.run(JobClient.java:557)     at java.security.AccessController.doPrivileged(Native Method)     at javax.security.auth.Subject.doAs(Subject.java:415)     at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1628)     at org.apache.hadoop.mapred.JobClient.submitJobInternal(JobClient.java:557)     at org.apache.hadoop.mapred.JobClient.submitJob(JobClient.java:548)     at cascading.flow.hadoop.planner.HadoopFlowStepJob.internalNonBlockingStart(HadoopFlowStepJob.java:100)     at cascading.flow.planner.FlowStepJob.blockOnJob(FlowStepJob.java:248)     at cascading.flow.planner.FlowStepJob.start(FlowStepJob.java:172)     at cascading.flow.planner.FlowStepJob.call(FlowStepJob.java:134)     at cascading.flow.planner.FlowStepJob.call(FlowStepJob.java:45)     at java.util.concurrent.FutureTask.run(FutureTask.java:262)     at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)     at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)     at java.lang.Thread.run(Thread.java:745)   Either this error due to cascading issue or due to java null pointer exception. If any details needed please let me know.


I have to deliver a statistical analysis plan that will have to be approved by an ethic commettee before I could start a clinical trial.   I usually deal with different kinds of tests, whose power analysis is straightforward and, given the expected effect size, a given statistical significance (Type I error), and a desired power (1 - Type II error), I can easily obtain the needed sample size.  However, this time I am planning to use logistic and ordinal regressions. How can I determine the sample size needed to perform an analysis with a given power, a given statistical significance, and an expected effect size (in terms of odds ratio, I guess)?  Before asking such a question I googled, but I found only some tables related to "standard" cases with one or two regressors, wheras in my case I have several predictors: discrete variables, dummy variables, ordinal variables, and continuous variables.


I'm currently trying to add arrows in my synthetic division example to show people clearly how synthetic division works. I'm working on Overleaf.   The code for my synthetic division right now is:  \begin{tabular}{c |r r r r r}     &1& 4 & -1&16&-20\\   1&& 1 & 5 & 4&20\\   \hline    &1 &5 & 4 & 20 &\rule{3pt}{16pt}\;0\\   \end{tabular}   How would I add arrows to this? For instance, a down arrow going from the first 1 to 1, then an upwards arrow pointing right from 1 to 1, then an arrow pointing down from 1 to 5, etc. Basically I would like to add arrows that look like this:


Emails goes to spam when using domain name in tag

I have Two domain. For Example: domain1.com and domain2.com. I am sending email using PHPMailer and I used   $email_body="View"   Above code is working perfectly and emails also go to inbox but when I am using my second domain instated of first then emails are going to spam.  $email_body="View"   Even I tried  "View" "View"   If I remove domain2.com and type some dummy text then also emails go to inbox. Would you help me in this?


Assign bitwise operators in to variable in java

I try to assign bit wise operators into variables. How can i do it?  Eg      String bitOp="";          String rFunction=JOptionPane.showInputDialog(null,"Enter Your round function","Round function",JOptionPane.INFORMATION_MESSAGE);           if(rFunction.toUpperCase()=="AND")              bitOp="&";          if(rFunction.toUpperCase()=="OR")              bitOp="|";          if(rFunction.toUpperCase()=="XOR")              bitOp="^";      int res= x +bitOp+ y; // if the operator is "AND" , this should be x & y.                           //Here NumberFormatException error shows.     System.out.print(res);   But it doesn't work. Anyone please!!!


Which book about relativistic space travel am I thinking of?

I'm trying to remember the title of a book I read years ago.  I think it was "the travelers" or "the journeyers" or something like that. It was about a group of human scientists that go on a long trip at relativistic speeds to visit a planet believed to have alien life.  There's a parallel story about the humans left behind. As they colonize space, a culture of spacefarers who run the routes between colonized planets materializes. They have their own culture separate from any of the planets they visit, because the time effects prevent them from getting to know anyone other than other spacefarers.  The ones on the trip to the inhabited planet have various relationships form and evaporate. They eventually get there, and meet the aliens, who are intelligent. A physicist on board figures out how to map their sciences to one another. The aliens use a different set of basic measurements (as opposed to time, length, and mass).  The aliens have a different method of reproduction, and ask the humans to demonstrate sexual reproduction with two genders.  Any help would be appreciated, thanks.


How do I execute a command relative to an entity in 1.15?

Already found similar posts like (), but those are some years old already and very outdated, what would be the new way to use the execute command relative (e.g. slightly behind) an entity? I'd guess it something with at @s[z=.5] or using the positioned tag, but neither of those worked yet. This is what I would like to accomplish, so that only in the right get stop the run command when they are in range, not both on the right and the left.  This is the actual detection range, where it detects the armor stand behind an infront of it.  And this would be the new detection range, where it only stops my execute command, when theres an armor stand in front of it.  All in all what I need is a way to reposition the anchor of the distance=0.5..1 tag, so that it's not the entity itself but rather e.g. +0.5 in the z coordinate


I have this json file  myjson=[{u'faceRectangle': {u'height': 72, u'left': 214, u'top': 125, u'width': 72}, u'scores': {u'anger': 0.180509463,  u'contempt': 1.50903434e-05, u'disgust': 0.008213697, u'fear': 0.418243885, u'happiness': 0.0259612668, u'neutral': 0.0001996803, u'sadness': 0.00102899456, u'surprise': 0.365827948}}]   I want to print from scores the sentiment that has the biggest probability with its probability next to it.   Any suggestion?  Thanks


How do I avoid loss of precision with doubles in Java?

I am writing a program that takes raw double values from a database and converts them to 8-byte hex strings, but I don't know how to prevent loss of precision. The data recieved from all devices are stored as doubles, including the 8-byte identification values. Instances of doubles such as 7.2340172821234e+16 parse correctly without loss of precision, where the exponent is 10^16. However, in instances where the exponent is 10^17, Java loses precision. For example, 2.88512954935019e+17 is interpreted by Java as 1.44464854248327008E17 The code I am using looks like this: public Foo(double bar) {     this.barString = Long.toHexString((long) bar);     if (barString.length == 15) {         barString = "0" + barString; //to account for leading zeroes lost on data entry     } }  I am using a test case similar to this to test it: @Test public void testFooConstructor() {     OtherClass other = new OtherClass();          OtherClass.Foo test0 = other.new Foo(72340172821234000d); //7.2340172821234e+16     assertEquals("0101010100000150", test0.barString); //This test passes          OtherClass.Foo test1 = other.new Foo(144464854248327000d);//1.44464854248327e+17     assertEquals("02013e0500000758, test1.barString); //This test fails }  The unit test states: Expected: 02013e0500000758 Actual:   02013e0500000760  When I print out the values that Java stored 72340172821234000d and 144464854248327000d as it respectively prints:  7.2340172821234E16 1.44464854248327008E17  The latter value is off by 8, which seems to be consistent for the few that I have tested. Is there anything I can do to correct this error? EDIT: This is not a problem where I care about what is past the ones place. The question that some think this is a duplicate of is asking why floating point numbers are less precise, I am asking how to avoid the loss of precision, through similar workarounds to those that  suggested.


I have 24 points which correspond to 12 different "elements" (2 points per element) saved in an .csv file with the following column order (1: Element Name, 2: x, 3: y, 4: z).  I would like to import them so that there will be an edge between the two points for every element.  Alternatively if this is not possible. It would be great to import all the points as separate elements. So I can know which points correspond to which element by the order of import.   Update:   This is great and I would like to extend this to the first six point: I tried to update your code with the edges I want, but it fails.   What does ensure_lookup_table() do ?  In if row[0] there is only one vert. How can I add more ? The Ideal solution would be select 1,6 or all verts and make a mesh.  The order of the edges would be cool to have but if too much hustle.  Just importing 1, 6 or all verts and connecting them to a mesh would good.    Here my attempt to updated your code:  import bpy import bmesh import csv from mathutils import Vector from bpy_extras.object_utils import object_data_add  csvfile = open('path2csvfile')  inFile = csv.reader(csvfile, delimiter=',', quotechar='"') # skip header inFile.__next__()  for row in inFile:     #  column order (0: Element Name, 1: x, 2: y, 3: z)     if row[0] not in bpy.data.objects:         vert = [Vector((float(row[1]),float(row[2]),float(row[3])))]         mesh = bpy.data.meshes.new(name=row[0])         mesh.from_pydata(vert, [], [])         object_data_add(bpy.context, mesh)     else:         bpy.data.objects[row[0]].select = True         bpy.context.scene.objects.active = bpy.data.objects[row[0]]         bpy.ops.object.mode_set(mode='EDIT')         mesh = bmesh.from_edit_mesh(bpy.data.objects[row[0]].data)         mesh.verts.new((float(row[1]),float(row[2]),float(row[3])))         mesh.verts.ensure_lookup_table()         mesh.edges.new([mesh.verts[0],mesh.verts[1]])         mesh.edges.new([mesh.verts[1],mesh.verts[2]])         mesh.edges.new([mesh.verts[2],mesh.verts[3]])         mesh.edges.new([mesh.verts[1],mesh.verts[4]])         mesh.edges.new([mesh.verts[4],mesh.verts[5]])         bmesh.update_edit_mesh(bpy.data.objects[row[0]].data, True)         bpy.ops.object.mode_set(mode='OBJECT')


I am new to Linux and on of my projects is to find all .config files. I made sure to be logged in as root. What command would I run to do this.


How can I install AMD ATI Catalyst Display Driver In Ubuntu 13.10 64bit?

Hello I was wondering if I can install AMD Catalyst 13.1 Proprietary Linux x86 Display driver. I am running Ubuntu 13.10 Beta 64bit and the card in question is listed under the AMD Radeon HD 3000 series. I have tried the most recent driver and when the computer loads it hangs and never loads so I have to restart in recovery and remove it to boot into my computer. I want 3d acceleration to work is the reason why I am trying to get this to work as well as being able to adjust for overscan problems with my tv. Thanks for any help.


How can I change the font and color of a particular command in a LaTeX document?  For example I want all the text that follows the \item tag to be gray and the font should be different from the rest of the document , which i can specify ...


How I can create a shortcut to maximize/minimize windows in Lubuntu?

In lubuntu-rc.xml Lubuntu doesn't have a hotkey to maximize the current window.


How local gauge invariance explain charge conservation and electromagnetic force appearance?

Without electromagnetic coupling, the QM charged particle wave function is not invariant under a local gauge transformation — one with a phase that depends on space (space-time): \begin{equation} \psi \mapsto e^{-i\alpha(x)}\phi \end{equation} In order to turn on the electromagnetic coupling, we make the replacement $$\hat{\vec{p}} \mapsto \hat{\vec{p}} - \frac{ie}{c}\vec{A}$$ This means that, in the Schrodinger equation is gauge invariant because the term arising from $\vec{A}$ is cancelled through the action of $\hat{\vec{p}} = i\hbar\partial$ on the phase factor $e^{-i\alpha(x)}$ in the wave function. The math trick is clear. But physics cannot be understood from it, namely, why the requirement of local gauge invariance requires 1) the charge conservation 2) and the emergence of some kind of carrier of interaction.


I'm trying to work out how I could configure my machine (presumably my machine's DNS settings) to resolve subdomains to the appropriate full domain of my site, mostly for shorthand purposes in development. For example, I would like 'www' to resolve to 'www.mysite.com', 'blah' to 'blah.mysite.com' and so on.  I don't really know where to start other than that I'm pretty sure this is outside the remit of simple /etc/hosts shenanigans. Will I need to run a local DNS server?


I'm trying to find out what percentage of things I am.   I know that my great grandmother on my mothers side is from Italy and that my grandmother is part cherokee indian as well, and my grandfather's mother is from Russia.   My mom only claims to be cherokee and italian, my father is welsh, and from europe in other places.


Quadratic congruences equivalent statements

Prove that for every prime $p>3$,   $L= x^2-x+2 \equiv 0\mod p$ has a solution iff $D=x^2-x+16 \equiv 0\mod p$ has a solution.  This is not true, right? If $L \equiv 0$ mod$p$, then $D=L+14 \equiv 14\mod p$, and $14$ is not congruent to $0\mod p$, when $p \neq 7$.


AngularJS: angular.js:11607 TypeError: Cannot set property '0' of undefined

I keep getting an error in a simple for loop trying to insert value from one array to another. My JS code is as:  var myApp = angular.module('myApp', []); myApp.controller('UserCtrl', function($http) {     let vm = this;     var datetime = [];     var venuename = [];     var venuecity = [];     var venuecountry = [];     var url = [];      var arr = [];     var id = "secret key";     vm.searchText;     var i=0;      vm.getByID = function() {          $http.get("https://rest.bandsintown.com/artists/" + vm.searchText + "?app_id="+id)         .then(response => {             console.log(response.data)             vm.name = response.data.name             vm.thumb = response.data.thumb_url             vm.fb = response.data.facebook_page_url             vm.up = response.data.upcoming_event_count             $http.get("https://rest.bandsintown.com/artists/" + vm.searchText + "/events" + "?app_id="+id)             .then(response2 => {                 console.log(response2.data)                 vm.arr = response2.data                 console.log(vm.up)                 console.log(vm.arr[0].datetime)                 console.log(vm.arr[1].datetime)                 for (i = 0; i <=(vm.up-1); i++){                     vm.datetime[i] = vm.arr[i].datetime;                     vm.venuename[i] = vm.arr[i].venue.name;                     vm.venuecity[i] = vm.arr[i].venue.city;                     vm.venuecountry[i] = vm.arr[i].venue.country;                     vm.url[i] = vm.arr[i].url;                 }                 console.log(vm.up)             })         })     } });   The datetime part of the arr returns just as i want it to. I just cant store it into the new array. What im trying to do is that the array 'arr' contains all the objects of concerts of an artist. I want to display the individual details, for that I need to store each element in a new array, and repeat to create and show separate event details. Im a newbie at this and any help would be appreciated. Thanks in advance!