I am trying to solve a problem I made form myself: proving that  $$\sum_{n\geq0}\left(\frac12\right)^n\prod_{k=1}^{n}\frac{2n-2k+1}{2n-2k+2}=\sqrt2$$ The highly accurate powers of  seem to confirm my hunch. But how do I prove it?   I was just messing around with products and generating functions, and then I noticed that the numerical value of the sum in question was suspiciously similar to $\sqrt2$, so I conjectured the result. Unfortunately I found this completely by accident and have absolutely no idea of how to prove it.   Feeble attempt:  Define $$S(x)=\sum_{n\geq0}x^n\prod_{k=1}^{n}\frac{2n-2k+1}{2n-2k+2}$$ Which Wolfram says is equal to $$S(x)=\sum_{n\geq0}x^n\frac{(1/2-n)_n}{(-n)_n}$$ With $\displaystyle (x)_n=\frac{\Gamma(x+n)}{\Gamma(x)}$. But that doesn't really make sense because $\Gamma(0)$ is undefined. So all in all I'm just confused.   Could I have some help?    Edit:  According to the comments, it suffices to prove that  $$\sum_{n\geq1}\left(\frac12\right)^n\prod_{k=1}^{n}\frac{2n-2k+1}{2n-2k+2}=\sqrt2-1$$


How do you get the Mozzila Firefox Beta?

64 bit. Title explains it all. Just want Firefox beta.


I'm trying to replace letters in a string based on an array of letters.  What I'm doing so far is  var value = '00-.Tday(52)' if(!textService.containsLettersExcept(value, ['t', '.', '-'])){     // yay }         function containsLettersExcept(text, exceptions){             console.info('text before : ', text)             for(var i = 0; i< exceptions.length; i++){                 var char = exceptions[i];                 text = text.replace(/char/gi, '');             }             console.info('text : ', text)             return text.match(/[a-z]/i);         }   This however  tries to remove the string "char" rather than the variable char from the string text


How do I retrieve a value from a [Flag] enum property?

Say I have an enum defined like so:  [Flags] public enum LogLevel {     None = 1,     Pages = 2,     Methods = 4,     Exception =8 }   and a class like:  public static class Log {     public static LogLevel Level = LogLevel.Methods | LogLevel.Pages;      public static void EnterPage([CallerFilePath]string filePath = "")     {         if (Level == //What value here to check if Level includes Pages?)         {              //Log         }     }   What value do I need to equate Level to to check whether the enum includes Pages?


Finding the determinant of a $5\times 5$ matrix


How to align at multiple positions when each line is a single equation?

I have equations of which each one has two equal signs. I want to align those equations at both positions of equal signs, like:  a =  b + c = d e = 2b + c = f   By using two "&"s, each line will be seperated, which is not what I want. Is there a good way to do that?


How to make a file which when exectued will install multiple packages in Ubuntu?

I want to make a file which when executed would install all the packages listed inside it like pip install numpy, pip install pandas and others.  How is this done? please guide me to appropriate resources for learning. Thanks


How to minimize spacing b/w subfigure and label less than 1cm?

I want to reduce spacing b/w labels and figures. But after the label to be very close to subfigues but with the following setting I can't reduce it less than 1cm.  \documentclass[aps,twocolumn,amsmath,amssymb,]{revtex4} \usepackage{graphicx} \usepackage{subfig} \usepackage{floatrow} %\floatsetup[figure]{style=plain,subcapbesideposition=top} \setlength{\labelsep}{1cm} \begin{document} \begin{figure*}[!htb]      \sidesubfloat[]{\includegraphics[width=\textwidth]{Fig1.png}}      \sidesubfloat[]{\includegraphics[width=\textwidth]{Fig2.png}}      \sidesubfloat[]{\includegraphics[width=\textwidth]{Fig3.png}}     \sidesubfloat[]{\includegraphics[width=\textwidth]{Fig4.png}} \end{figure*} \end{document}


How many words can be formed from 'alpha'?

How many words can be formed from the word 'alpha'? The letter 'a' may be used twice but the other letters may only be used once.  There are no restrictions on whether or not they're real words, just combinations of letters. So, I need to add together:  $5$ letter words $+$ $4$ letter words $+$ $3$ letter words $+$ $2$ letter words $+$ $1$ letter words  There are, $(5!/2!)=60$, 5 letter words. 120 total but then we divide out by duplicate words because we have two a's.  $1$ letter words $=4$  The part I am having trouble with is the duplication of 'a'. I can't seem to figure out how to find $2,3,$ and $4$ letter words. For 2 letter words, there were so few examples I just wrote them out and saw that there were 13. So,  $(5!/3!)-[(2!)3+1]=13$  20 possibilities and then we need to subtract out the ones that contain 2 of p,l, and h, as well as the second aa.  I'm having a hard time believing my work for 2 letter words is accurate and attempting to do 3 and 4 letter words suggests that it isn't. Let me know if there is anything I can to do clear up what is being asked. Thanks in advanced.


Separate shader programs or branch in shader?

I have a bunch of point lights and directional lights. Instead of checking the light type in the fragment shader and then branch for either point light calculation or directional light calculation, is it more efficient to use two separate programs, one for point lights and one for directional lights?  (Using deferred shading in OpenGL 3.3)


Mathematical Logic: If I don’t have to show something, why is it always correct?

Let’s assume I have to show it for every element of my set. But when my set is empty, it is right. How can we say that this is true, because I could also say I had to show nothing, so it has to be false. Thank you for your answer.


How to implement one "catch'em all" exception handler with resume?

I wonder how can I write a catch'em all exception handler in the application level which will give the user the option to resume the application flow?


grub-efi-amd64-signed package failed to install into/ target on installation from 16.04.4 live usb on Dell Inspiron 3180

I am trying to install Ubuntu 16.04 on my laptop (Dell Inspiron 3180). I tried a live 18.04 USB first of all but it kept freezing after a few seconds, keypad or touch pad wouldn't work both when trying the installer and running live. Windows 10 was pre installed on the laptop  I made a 16.04.4 USB, when I tried this live, the touchpad wouldn't work, but I was able to navigate and use the keypad. I figured if I could complete the installation it would free up the USB slot for me to try a wired mouse which might work. I began the installation and everything worked until I received the error:     'grub-efi-amd64-signed' package failed to install into/ target/. without the grub boot loader....   I couldn't read the rest as the installation was trying to move on and the screen faded and powered down. When I restarted the PC it was running a hardware diagnostic.   Any ideas on what to try would be appreciated?   showing how I tried the installation step by step


How to create a specific math-alphabetic letter?

I'm preparing an essay which should contain the following letter:    I'm a newbie in the world of TEX, and I don't know how to get it. Can somebody help me?


What is the difference between "attribute" and "property"?

Could you please clear up the meaning of these two words for me?  I don't understand this sentence:      Attributes introduced by RDFA have names. For example, property is one such attribute.


No 3D acceleration in Ubuntu 14.04 LTS with latest Vmware Workstation

I installed the latest version of vmware workstation (10.0.2) in ubuntu 14.04 LTS and I have the following problem:    I use the open source driver "Radeon" (Galium 0.4) and Mesa 10.1.0.  My graphics card:  glxinfo | grep OpenGL  OpenGL vendor string: X.Org OpenGL renderer string: Gallium 0.4 on AMD RS780 OpenGL core profile version string: 3.1 (Core Profile) Mesa 10.1.0 OpenGL core profile shading language version string: 1.40 OpenGL core profile context flags: (none) OpenGL core profile extensions: OpenGL version string: 3.0 Mesa 10.1.0 OpenGL shading language version string: 1.30 OpenGL context flags: (none) OpenGL extensions:   lspci -nnk | grep -iA3 VGA  01:05.0 VGA compatible controller [0300]: Advanced Micro Devices, Inc. [AMD/ATI] RS780D [Radeon HD 3300] [1002:9614] Subsystem: ASUSTeK Computer Inc. Device [1043:834d] Kernel driver in use: radeon 01:05.1 Audio device [0403]: Advanced Micro Devices, Inc. [AMD/ATI] RS780 HDMI Audio [Radeon (HD) 3000 Series] [1002:960f]  glxinfo | grep -i render  direct rendering: Yes GLX_MESA_multithread_makecurrent, GLX_MESA_query_renderer, OpenGL renderer string: Gallium 0.4 on AMD RS780 GL_MESA_texture_signed_rgba, GL_NV_conditional_render, GL_NV_depth_clamp, GL_NV_blend_square, GL_NV_conditional_render, GL_NV_depth_clamp,   I tried to install driconf and changed Enable S3TC texture compression...by default is No, and also edited the .vmx file, adding the line:  mks.gl.allowBlacklistedDrivers = "TRUE"   But it doesn't work.  I checked if this package is in my system:  libtxc-dxtn-s2tc0   I think it is a free implementation of the texture compression library for Mesa. This package is installed by default on Trusty.  Any help would be greatly appreciated  Best Regards.


I am extremely new to mathematics, and I don't have much training except for the basics so please excuse my rather basic question.  The question itself:  If I have the relationship $e^x + x - 2 = 0$;  and $k$ is the number of solutions in $[0,1]$ and $n$ is the number of solutions not in $[0,1]$  what is $k$? what is $n$?  My Questions (sorry if they are many)  (1) What is the proper name for this type of equation. It doesn't seem to be a function, just a relationship of one variable to some constants.  (2) How do you tell how many solutions an equation like this has just from looking at it? It seems like if you have an equation like $x^2 + 2x + 5 = 0$; you have at least two solutions. But what about the $e^x$? How do you predict how many solutions there will be then?  (3) Once I re-arrange the equation to $e^x + x = 2$; what algebraic steps could I follow if I wanted to find the exact solution?


Flag dialog tells me I've flagged a post I've never seen before

I spotted a  (10k-only by now) and when I went to flag it, the flag dialog told me that I'd already flagged it as VLQ:    The thing is, I'd never seen this post before. And a look at the flag history in my user profile confirms that I haven't flagged a post since yesterday:    Certainly, well before the 2015-02-04 05:36:21Z time of Mr. Miracle's post.  I was able to reproduce this on SO from the VLQ review queue: when you're presented with an answer, click on link at the right side of the page, then click flag. You get the "you have already raised this type of flag" message on either the "it is not an answer" or "it is very low quality" options, I gather depending on the original flag that pushed the post into the VLQ queue.


What was the first instance of a relationship between werewolves and vampires?

What was the first known instance of a story that provides a relationship between werewolves and vampires? What was that relationship?  In some movies (Underwold, Van Helsing and Twilight), werewolves are portrayed as the vampires' slaves: as the latter represented the aristocratic class, who were on the top food chain thanks to their human-like appearance and self-control. Totally the opposite for the werewolves, who were simply seen like savage beasts, who cannot control themselves (Twilight, Underworld).


How to find the Flixbus timetable for a specific route?

Is there any way to see the timetable for a  bus route?  On their website I can see the routes map, but I'd me more interested in seeing where the bus is going to stop for a given route.  E.g. if a bus goes from Rotterdam to Amsterdam, I'd like to see each stop.


I have been trying to solve for $\vec{r}$:  $\vec{a}\times \vec{r} + \lambda \vec{r} = \vec{c}$   And I thought of using a triple scalar product, I dot both sides with $\vec{a}$:  $\vec{a} \cdot (\vec{a}\times \vec{r}) + \lambda \vec{a} \cdot \vec{r} = \vec{a} \cdot \vec{c}$  And now since the triple scalar product is cyclic $\vec{a} \cdot (\vec{a}\times \vec{r}) = \vec{r} \cdot (\vec{a}\times \vec{a}) = 0$, so the main equation becomes:  $\lambda \vec{a} \cdot \vec{r} = \vec{a} \cdot \vec{c}$  And I do not know how to proceed from here. I cannot use the dot product again, $\vec{a}$ cannot be canceled out. I am not sure whether this approach is right in isolating the $\vec{r}$ but it seems closer to the answer.


Why won't 3 of the women who have been pregnant for about 24 hours give birth?

I expanded my vault and added more living quarters and built storage. I have enough resources im fairly sure. The three women are working, but that shouldn't be a problem. I don't know if being armed with weapons would do anything, but they are armed. This is really confusing...


How to add a box underneath the Post Box in Wordpress admin?

I'm wondering how to add a new box underneath the Post Box (Publish Box) in the admin section of WordPress?  Am hoping to add a few custom field text inputs there.


I'm trying to write some code in the <head> like this, but it doesn't work:  <!DOCTYPE html> <html> <head>   <script type="text/javascript">     document.writeln('<script src="js/messages.js"></script>');    </script> </head> <body>  <script> </script>  </body> </html>   It prints '); in the page and   <head>   <script type="text/javascript">     document.writeln('<script src="js/messages.js"></script>');    </script> </head>   in the code.


Is it possible to access file with extension *.txt or *.file in JavaScript?  I want to call this file in my function?


Why is methane considered an important greenhouse gas?

Methane’s absorption bands are centered at 3.2 and 7.2 microns -- far off the peak of the Planck spectrum for a 290 K blackbody near 16 microns.  Moreover, its absorption bands overlap with the water absorption region.  So why is methane considered a stronger greenhouse gas than carbon dioxide, which has an absorption band at 15 microns?


Short story about a writing machine that learns from the writer and eventually writes on its own

I'm looking for a short story, probably written in first person, about a writer. His writing machine (a typewriter, I think) breaks down, so he buys a replacement. Typewriters aren't sold any more, so he buys a newfangled writing machine that 'learns from the writer'. It works well at first, but then starts acting up when he types. Corrects his spelling, grammar, word placement stuff like that. At some point, he calls customer service for help, gets told that these are new machines, they don't know much about them, or something along those lines.  At the end, the character wakes up one morning, to find the writing machine writing all by itself, in his writing style, but better, and faster than he could write. The character ponders "What am I to do now?"  I'm fairly certain I read this story in a book or an anthology, not a magazine. I don't remember when I read it, but it was probably at least 5 years ago, and the story probably wasn't new then. I read the story in English. I don't think it was translated from another language.


Why can't I create directories under /root as a member of root?

I've done the following:  sudo usermod -a -G root userA sudo su - root cd / chmod 775 root ls -aln -- drwxrwxr-x.   6 0 0 4096 Sep 13 22:04 root   I can cd /root from my userA, but I can't make directories.  mkdir testing mkdir: cannot create directory ‘testing’: Permission denied   For completeness:  id userA uid=624981(userA) gid=624981(userA) groups=624981(userA),10(wheel),0(root)   What am I missing?


Prove: $\frac1x$ is not a uniformly continuous function

I have to prove that $\frac1x $ with $x \in (0,\infty)$ is not uniformly continuous. I understand that the further you approach the $0$ the greater your $e$ and the smaller your $\delta$ becomes (in the limit even $\delta = 0 $ ?).  But I need help with the "technical" proof, can someone give me an instruction to do this?


creating many Shapefiles from from a single multi-polygonal shapefile using ArGIS tools

I have a country shapefile with many districts polygons which are administrative boundaries, I want to have a shapefile for each of the district, which tool in ArcGIS can I use to accomplish this


How to print a brochure on Photoshop CS6 without white borders?

I'm making a tri-fold brochure that will fit on a 8.5 x 11 piece of paper. I would like it to completely fill the paper, however it keeps printing with white borders around it. How can I fix this?


What is the difference between "the door opened" and "the door was opened"?  Are there subtle differences?


Ubuntu Nvidia drivers vs Nvidia drivers from the website

What is the difference?  I can see that the 'Additional drivers' section installed drivers that are older than the latest ones available on the website.  Are there any drawback to installing Nvidia drivers straight from the website with the .run file?


Lenovo thinkpad keeps disconnecting from wifi, but the icon shows connected

Device: Lenovo Thinkpad X1 Carbon (3rd generation) running Ubuntu 16.04  Problem: The wifi keeps disconnecting in my home network, which slightly weaker than the wifi at work. The wifi at work is more stable, still disconnects on occasion. At home however it disconnects repeatedly, every few seconds of connecting sometimes. My android phone however stays connected without problems.  Description: When it disconnects the wifi icon does not change, but the internet stops working in applications and browsing. If I disconnect and reconnect it works again for an amount of time before disconnecting again in this manner.  Attempts: Reading around solutions I've set IPv6 method to "Ignore" in network connections settings. This has had no effects, I am not sure at this point how to fix this issue.  Running lspci -knn | grep Net -A3 gives:  04:00.0 Network controller [0280]: Intel Corporation Wireless 7265 [8086:095b] (rev 59)     Subsystem: Intel Corporation Dual Band Wireless-AC 7265 [8086:5210]     Kernel driver in use: iwlwifi     Kernel modules: iwlwifi


How to divide circle multipart nodes in tikz

I would like to get multi part node with vertical line between lower nodepart. Something like this:    My code:     \documentclass{article}     \usepackage{tikz}   \usetikzlibrary{arrows}   \usetikzlibrary{shapes.multipart}   \begin{document}   \begin{tikzpicture}[->,>=stealth',shorten >=1pt,auto,node distance=3cm,   thick,main node/.style={circle,fill=blue!20,draw,font=\sffamily\Large\bfseries}]   \node [circle split,draw,double,fill=red!20]   {   $q_1$   \nodepart{lower}    {   test1   }   {   test2   }   };   \end{tikzpicture}   \end{document}   What should i add to this to get vertical line between test1 and test2?


soffice converted .ods file ,Failed to read .ods file using jOpenDocument API

I have converted .xls file to .ods by using below command in terminal  COMMAND : soffice --headless --convert-to ods abcd.xls   After conversion I am not able to read fileName.ods using SpreadSheet API of jOpenDocument1.3.jar. When ever I try to read .ods file it will throw NullPointer Exception .  I am working in Ubuntu platform, if I convert .xls file to .ods using LibreOffice then it is working fine but if I convert it using soffice terminal then it is throwing exception!.   Is there any way to convert file(s) using command line, so that Java code able to read it properly.    I am using below code to read converted fileName.ods file .  File file = new File(path); String sheetName = "SheetName"; // spread Sheet Name Sheet sheet = SpreadSheet.createFromFile(file).getSheet(sheetName);   "createFromFile" is giving NullPointer Exception  ava.lang.NullPointerException     at org.jopendocument.dom.ODPackage.getODDocument(Unknown Source)     at org.jopendocument.dom.ODPackage.getSpreadSheet(Unknown Source)     at org.jopendocument.dom.spreadsheet.SpreadSheet.createFromFile(Unknown Source)     at com.thales.dbtool.controller.DBManageController.getUiParamsFromExcel(DBManageController.java:1316)     at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)     at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)     at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)     at java.lang.reflect.Method.invoke(Method.java:498)     at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:221)     at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:137)     at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandl   Any help will be appreciated.


How do I cite authors in LaTeX?  I tried using natbib package  ---- doc.tex ----  ... \usepackage{natbib} ... \citeauthor{736184} ...   ---- doc.bib ----  @inproceedings{736184,      author = {Broder, Andrei Z.}, ...   but all I get is (author?) (in bold).


Python Class member variables initilialization?

Came across one Python Class and I am finding it hard to understand how and why its working . A simplified example of the class is :  class Test:   def __init__(self):     self.var = 1    otherVar = 2    def myPrinter(self):     print self.__dict__  # Prints {'var': 1}     print self.var     print self.otherVar  # Doubt !!     print self.__dict__  # Prints {'var': 1}  ob = Test() ob.myPrinter()   My doubt is with the self.otherVar call not throwing an error while self.__dict__ does not show reference to otherVar


A help in demonstration of $\lim$ 0f lebesgue integral

If $f\in L^p(\mathbb{R^n})$ $1\leq p < \infty$ then prove $\displaystyle\lim_{|h|\to 0} \|f(x + h) - f(x)\|_p = 0$.  I had tried to prove the continuity a.e. of $\|f(x + h) - f(x)\|_p$, then could pass the $\lim$. This way is good or there is other more simple?


Proof of "Dual normed vector space is complete"

As in the introduction of dual norm by Wiki, it says dual normed space $X'$ is always complete.  How to prove that? or at least explain that?  We all know the normed vector space is not always complete; if complete, all Cauchy sequences convergent. However, dual normed vector space is complete?


Assuming you're parents that see your young son doing something you don't like, and you want to avoid him to do it. What's of these following ways more natural?  Don't do it!  or  Don't do that!


How to determine contractor hourly rate and employee salary equivalents?

I am aware of the general differences between being an employee and being an independent contractor.  However, I am unable to easily compare the two when it comes to after-tax compensation.  Company A:  You're a contractor (1099).  You get paid $X/hour.  You genuinely act like a contractor and aren't secretly an employee.  Company B:  You're an employee (W2).  You also get paid $X/hour.  You genuinely act like an employee and aren't secretly a contractor.  If absolutely everything about the two companies are the same except your status as an employee/contractor, you'd be better off as an employee because you end up paying less taxes.  Your after-tax income will be higher.  But where's the dividing line?  Is there a simple formula that tells you the equivalent employee rate given a specific contractor rate?  I completely understand that this involves simplifications and won't be perfectly accurate.


How to search for installed packages which have dependancy on Python?

I am looking to make a list of packages which have dependancy on Python. How to search for it ?  Another two would be that the dependency would be in recommends (1) or suggests (2) . But when Python is in suggests then show suggests only, or if Python is in recommends then show only those packages which have Python in recommends.


Why is a 103Z capacitor use with N20 DC motor?

So capacitor 103z is used in parallel with N20 DC motor, I would like to know why?


Generate a 100 Hz Clock from a 50 MHz Clock in Verilog

I have a DE0 board with a 50 Mhz clock that am I trying to to bring down to 100 Hz in Verilog. Could anyone help me with the code to do this?


Out Of Memory Exception with custom GridView

I have this code of a custom grid view and each time I try to run it, it crashes caused by an OutOfMemoryException. I guess the solution is to resize the images in the array ...  main activity code :  public class AndroidGridLayoutActivity extends Activity {          @Override         public void onCreate(Bundle savedInstanceState) {             super.onCreate(savedInstanceState);             setContentView(R.layout.grid_layout);              GridView gridView = (GridView) findViewById(R.id.grid_view);              // Instance of ImageAdapter Class             gridView.setAdapter(new ImageAdapter(this));              /**              * On Click event for Single Gridview Item              * */             gridView.setOnItemClickListener(new OnItemClickListener() {                 @Override                 public void onItemClick(AdapterView<?> parent, View v,                         int position, long id) {                      // Sending image id to FullScreenActivity                     Intent i = new Intent(getApplicationContext(), FullImageActivity.class);                     // passing array index                     i.putExtra("id", position);                     startActivity(i);                 }             });         }    }   image adapter code :  public class ImageAdapter extends BaseAdapter {     private Context mContext;      // Keep all Images in array     public Integer[] mThumbIds = {             R.drawable.pic_1, R.drawable.pic_2,             R.drawable.pic_3, R.drawable.pic_4,             R.drawable.pic_5, R.drawable.pic_6,             R.drawable.pic_7, R.drawable.pic_8,             R.drawable.pic_9, R.drawable.pic_10,             R.drawable.pic_11, R.drawable.pic_12,             R.drawable.pic_13, R.drawable.pic_14,             R.drawable.pic_15     };      // Constructor     public ImageAdapter(Context c){         mContext = c;     }      @Override     public int getCount() {         return mThumbIds.length;     }      @Override     public Object getItem(int position) {         return mThumbIds[position];     }      @Override     public long getItemId(int position) {         return 0;     }      @Override     public View getView(int position, View convertView, ViewGroup parent) {                  ImageView imageView = new ImageView(mContext);         imageView.setImageResource(mThumbIds[position]);         imageView.setScaleType(ImageView.ScaleType.CENTER_CROP);         imageView.setLayoutParams(new GridView.LayoutParams(70, 70));          return imageView;     } }   full screen code :  public class FullImageActivity extends Activity {       @Override     public void onCreate(Bundle savedInstanceState) {         super.onCreate(savedInstanceState);         setContentView(R.layout.full_image);          // get intent data         Intent i = getIntent();          // Selected image id         int position = i.getExtras().getInt("id");         ImageAdapter imageAdapter = new ImageAdapter(this);          ImageView imageView = (ImageView) findViewById(R.id.full_image_view);         imageView.setImageResource(imageAdapter.mThumbIds[position]);     }  }   any advice please??


Will my USA iPhone work outside the USA?

We are planning to be in New Zealand for 10 months starting in August and currently are under contract with Verizon here in the USA.  I am thinking about suspending my Verizon account and getting local service in New Zealand.   The other option would be to switch to T-Mobile that has global roaming data.  Will our iPhones work in New Zealand?  Data is probably the most important part for us.


Array modifier and fit to curve does not work!

I am trying to add a chain to a bezier curve but when I hit fit to curve the chain is much shorter than the curve, and when I apply the curve modifier and parent it with the bezier curve it just places the chain above the curve and stretches the chain, distorting its geometry,  I have set the origin to the volume of the chain, I've set the chain right and where the 3D cursor is but nothing seems to help.


Books or papers on statistical mechanics, given information theory background?

What are some good books or papers on statistical mechanics, for someone who:   is familiar with information theory and statistics has a relatively weak physics background (1~2 year undergrad level) wants to learn key techniques in the stat mech literature doesn't care much about physical interpretations of such techniques


Could we get a clearer badge progress tracker for the Curious/Inquisitive/Socratic badges?

So I've asked 5 questions each with a positive score (and well-received, I guess) on 5 separate days. The badge indicator says that the task is complete (5/5), but I haven't been awarded that badge. Here's my profile:   After clicking on the badge, it says that I still need a "positive question record". I don't have any recently deleted or closed questions and I can't seem to remember any questions that have been closed or deleted in the past year.  It turns out , but there's no way for me to see it directly in the badge progress tracker, which is filled up entirely, giving the impression that the task is complete. You can only find out now that the task isn't complete by clicking on the badge progress tracker. I'm aware of  visible, but can we also have a better indication in the progress tracker that the task hasn't been completed yet?


How to set a font size in listing when I have these settings in the preamble?   \documentclass[12pt,a4paper]{report} \usepackage[most]{tcolorbox} \newtcbinputlisting[auto counter,list inside=lol,list type={lstlisting}]{\mylisting}[3][]{%   listing file={#3},   title=Listing,   colback=white,   colframe=gray!75!black,   fonttitle=\bfseries,   listing only,   breakable,   title={Soubor \thetcbcounter: #2},   #1 } \newcommand{\listingsfont}{basicstyle=\ttfamily\tiny}   \begin{document} \mylisting[label=s]{s}{s.txt}  \end{document}   File s.txt:  x = 5;
 y = 6;
 z = x + y;   I tried   \newtcbinputlisting[auto counter,list inside=lol,list type={lstlisting}]{\mylisting}[3][]{%   listing file={#3},   title=Listing,   colback=white,   colframe=gray!75!black,   fonttitle=\bfseries,   fontsize=\footnotesize,   listing only,   breakable,   title={Soubor \thetcbcounter: #2},   #1 }   There is an error and  \newcommand{\listingsfont}{basicstyle=\ttfamily\tiny}    that does not do anything - the font size remains the same.


How are the Unreal Development Kit (UDK) and Unreal Engine 4 (UE4) related?

I'm thinking of learning Unreal Engine 4, but it costs money, and I want to try and keep costs as low as possible while I'm learning. In contrast, the Unreal Development Kit is free.  How similar are the two? If I learn UDK first, how easily can I transition to UE4?


Ambiguous output redirect error in find command

Apologies if this is a repeated question, I am trying to search for a file in all the subdirectories in a given path. While doing so I also want to suppress any output messages, errors from the find command, so I am using the following command: find -L a/b/c/d/e -name file_name.xml -type f -print 2>/dev/null | xargs -l1 dirname  However, I am getting the following error: Ambiguous output redirect.  If I remove 2>/dev/null from my command I get the output message : a/b/c/d/e/my_folder/file_name.xml  Kindly give some guidance how to solve


What is the correct way of writing the support of a function in math mode?

So far i have been using $\text{supp} u$ but that is very cumbersome and probably wrong, do we have an equivalent of \lim for $\lim$?


I finally got fed up when wanting to read about bash's read and it's -s option with man bash. I found the right spot eventually (around line 4500), but it was a frustrating as usual, since both /read and even /\s-s\s searches have way too many matches.  So, the question is: How can I read long man pages efficiently, or get same information in other ways, locally? As a specific example, how to reach the relevant documentation after seeing read -s pwd in a shell script? A good answer could be a shell script snippet, or hint about some tool and how it is used, or something else entirely, as long as it helps in finding the right spot to read.  Note: I'm not tagging with  because I want the question to be about man page reading in general, even though that quite possibly is the most commonly encountered humongous man page.


I have a code that is testing a batch, I am creating a contact and an Account , but the contact isn't getting linked to the account (c.AccountId = null). The same code is tested in Async window and it is creating a contact linked to an account.      Account account = new Account();     account.RecordType = AccountUtilities.RecordTypes.get('Corporate_Golden_Record');     account.Name = 'test corp';     account.phone= '01123123';     account.billingcity='London';     account.billingpostalcode='SW1635HJ';     account.billingcountry='United Kingdom';     account.billingstreet='address 1';     account.retailer_email__c= 'corp@test1223.com';     insert account;       //Insert contact for Account     Contact c = new Contact();     c.AccountId = account.ID;     c.FirstName = 'test';     c.LastName = 'test';     c.email = 'test@test.com';     c.RecordTypeId = Schema.SObjectType.Contact.getRecordTypeInfosByName().get('Contact').getRecordTypeId();     c.Language__c = 'EN';     c.birthdate = Date.newInstance(1992, 04, 12);     insert c;       system.debug('-- Contact : ' + c.Account.Name);     system.debug('-- Contact : ' + c.ID);      Test.startTest();     ...     Test.stopTest();


How can I prevent an APP from using my phone's camera

I have some apps on my HTC One (M8) that want to have access to my camera and microphone (Yahoo Mail app).  I have seen on an iOS device that you can disable this access but still run the app.  Is there something similar in the Android world?


I've tried to write a graphic interface to my DataFrame project. I have to read DataFrame from file and then I want to count for example min for each column. I have an open button, so I can read a file, but I don't know how can I work on this file(if you know what I mean). When I tried to press min botton, there was a null pointer exception. I guess that the dataframe is empty. But what should I do to fix it? I also have to draw a graphs, but I totally do not know how to do it.  public class Graphics extends Application { private Text actionStatus; private Stage savedStage; DataFrame d; public static void main(String[] args) {     Application.launch(args); }  @Override public void start(Stage primaryStage) {     Button open = new Button("open");     open.setOnAction(new SingleFcButtonListener());     HBox open1 = new HBox(10);     open1.getChildren().addAll(open);     Button save = new Button("Save");     HBox save1 = new HBox(10);     save1.getChildren().addAll(save);     Button min = new Button("Min");     HBox min1 = new HBox(10);     min1.getChildren().addAll(min);      min.setOnAction(new SingleButtonListener());     actionStatus = new Text();        VBox vbox = new VBox(30);     vbox.getChildren().addAll( open1,save1, min,  actionStatus);     Scene scene = new Scene(vbox, 500, 300);     primaryStage.setScene(scene);     primaryStage.show();     savedStage = primaryStage;  } private class SingleFcButtonListener implements EventHandler<ActionEvent> {      @Override     public void handle(ActionEvent e) {         showSingleFileChooser();      }  }  private void showSingleFileChooser() {     FileChooser fileChooser = new FileChooser();     File selectedFile = fileChooser.showOpenDialog(null);      if (selectedFile != null) {          actionStatus.setText("File selected: " + selectedFile.getName());         ArrayList<Class<? extends Value>> arr2 = new ArrayList<Class<? extends Value>>();         arr2.add(Str.class);         arr2.add(DateTime.class);         arr2.add(com.projekt1.Double.class);         arr2.add(Double.class);         DataFrame d = new DataFrame(selectedFile.getName(), arr2, true);         d.showDatabase();     }  } private class SingleButtonListener implements EventHandler<ActionEvent> {      @Override     public void handle(ActionEvent e) {         showMean();      }  }  private void showMean() {     d.mindf().showDatabase();     }  }


Eclipse Luna update to 4.4.1 fails in Ubuntu 14 (32-bit)

With Luna running, I select the Help:Check for Updates option and am shown a list of updates, which are all checked except the one for Luna 4.4.1.   I hit "Select All" and try to update. It fails with this message:   An error occurred while uninstalling session context was:(profile=epp.package.standard, phase=org.eclipse.equinox.internal.p2.engine.phases.Uninstall, operand=[R]org.eclipse.platform_root 4.4.0.v20140606-1558 --> null, action=org.eclipse.equinox.internal.p2.touchpoint.natives.actions.CleanupzipAction). Backup of file /opt/eclipse-luna/notice.html failed. File that was copied to backup could not be deleted: /opt/eclipse-luna/notice.html


PrintWriter isn't writing to a file, but the split() seems to be working correctly?

import java.io.BufferedReader; import java.io.File; import java.io.FileInputStream; import java.io.FileNotFoundException; import java.io.IOException; import java.io.InputStreamReader; import java.io.PrintWriter; import java.io.Reader; import java.util.Arrays; import java.util.LinkedList;  public class ProjectTwoAccessControl{    // public static void fOrAAdd(String x,PrintWriter n){ //      n.write(x); //  }   public static void main(String [] args) throws IOException{     PrintWriter friends = new PrintWriter("friends.txt");      PrintWriter audit = new PrintWriter("auditlog.txt");    try { FileInputStream inputCommands;      inputCommands = new FileInputStream("test.txt");     BufferedReader br = new BufferedReader(new InputStreamReader(inputCommands));     String line;     while ((line = br.readLine()) != null){ //2         String[] command = line.split(" ");         System.out.println(Arrays.toString(command)); //      for(int i = 0; i < command.length;i++){ //1         if (command[0] == "friendadd"){             friends.write(command[1]);             audit.write("Friend " + command[1] + " was added.");          } //      } //1  } //2 }//try end catch (FileNotFoundException e) {     System.out.println("No file found by this name"); }     friends.close();     audit.close();  }          }   I am attempting to make a social media style of access control for a school assignment, and am going to continue working on this all evening, but I cannot figure out why the PrintWriters are not writing. I added in to print the array "command" out, and it seems to be working correctly, but nothing will print to my friends.txt or audit.txt.


The limit of $((1+x)^{1/x}-e)/x\;$ as $\;x$ tends to $ 0$

So, I have to solve the limit problem using a derivative.  The problem is as follows: $$\lim_{x\to0}\frac{(1+x)^{1/x}-e}{x}$$  I really don't know what to do. Can someone help?


Where does YouTube put videos on my device?

I want to know where YouTube stores the videos when I go offline. I know it's on my device somewhere, but I can't figure out where.


I was trying to solve the problem :   The function $f : \mathbb{R} \to \mathbb{R}$ satisfies $f(x) f(y) = f(x + y) + xy$ for all real numbers $x$ and $y.$ Find all possible functions $f.$   I started by substituting in $0$ for both, to find that $f(0) = 1$, as it becomes $f(0)f(x) = f(x)$ which can only mean $f(0) = 1$. However past this point, I started struggling, as setting both to $1$, or $1$ and $0$ doesn't reveal anything new about the problem. Trying to set both $f(x)$ terms equal to each-other didn't help either. Thanks!


math.stackexchange community. I have joined to inquire on a hypothesis a friend of mine has recently proposed. Please note: before posting this, I have repetitively told him that his logic is flawed in a plethora of ways. But I'll humor him, just this once.  This dear friend of mine claims that when [sic] divided by zero, infinity equals all real numbers, or as follows: ∞ / 0 = (-∞, ∞)  Oh, my fellow mathematicians and logicians, please inform my friend of either his grave error or his genius discovery. Thank you.


How do I find out what filesystem FUSE is using?

when I run mount, I can see my hard drive mount as fuseblk.  /dev/sdb1 on /media/ecarroll/hd type fuseblk (rw,nosuid,nodev,relatime,user_id=0,group_id=0,default_permissions,allow_other,blksize=4096,uhelper=udisks2)   However, fuseblk doesn't tell me what filesystem is on my device. I found it using gparted but I want to know how to find the fs using the command line utilities.


I recently purchased  from Amazon, and scroll lock key doesn't seem to work on Ubuntu, I am running Ubuntu 14.04 currently.  I tested the keyboard on Windows 8.1 as well, on the same computer, and scroll lock key works there. Is anyone else experiencing the same problem?


When can I say that $\cup H_i$ is a group?

Let $G$ be a group and $\{H_i\}_{i\in I}$ a family of subgroups. I would like to find a condition that will imply that $\cup_{i\in I} H_i$ is a subgroup. I know that it's not true in general, I need help to find this condition.  Any help is welcome.  Thanks a lot.


Speed difference in using inline strings vs concatenation in php5?

(assume php5) consider  <?php      $foo = 'some words';      //case 1     print "these are $foo";      //case 2     print "these are {$foo}";      //case 3     print 'these are ' . $foo; ?>   Is there much of a difference between 1 and 2?  If not, what about between 1/2 and 3?


How to get fragments of an exploded object to react more accurately to collisions with a plane?

Since a picture (or animated GIF in this case) is worth a thousand words, I will begin by providing an example of the problem I am trying to solve:    As you can see, the fragments of the monkey never change orientation as they fall and "bounce" off of the plane that they are colliding with.  I created this animation by adding a monkey to the scene and using the Object->Quick Effects->Quick Explode tool. The fragments never change their orientation, which is grossly unrealistic.  How do I fix this?


Is there any difference between run command in terminal & ALT+F2

For running direct commands, there are two ways.   Either run in Terminal Or run from the "Run Command" dialogue (screen shown below) obtained from Alt+F2     Then, Is there any difference between them? (working same & shell) or redirects to same?


Find MS Word docs by contents, not by extension

I believe there are MS Word docs on a Windows 10 system, but that their extensions have been changed to hide them. How can I search the file system, looking at file contents, not extensions, to identify any unlabeled Word docs?  Docs may be .doc or .docx, and may be password-protected.


(Safely) Disable dGPU on 2018 15" MacBook Pro?

Is there a way to safely disable the Radeon Pro 560X dGPU on the 2018 15" MacBook Pro?  I know I can go the other way (force dGPU only) via the 'Automatic graphics switching' check box in Energy Saver but that is the opposite of what I want to do :)  I know on older models it was possible via magic nvram options.  Is it even possible on the 2018 MacBook Pro?   Edit: I should mention I have tried gfxCardStatus (and a more up-to-date port) however this does not block the dGPU from becoming active it simply switches back to the iGPU if something does fire up the dGPU. I want to fully disable the dGPU so it cannot be activated.


How can I prove that a continuous injective function is increasing/decreasing?

If I have a continuous, injective function mapping the real numbers, then it is either increasing or decreasing.  This seems intuitively obvious but I can't come up with a neat proof for it.


Sometimes PowerShell stops sending output until I press enter. Why?

Periodically I notice PowerShell seems to take forever to finish doing whatever it is I told it to do until it occurs to me to "wake it up" by pressing enter. This is not the fault of any one process as best I can tell, as I have even run custom apps that just log their output to the screen every few seconds and even in these cases, PowerShell will stop doing anything after a while until I "give it a kick" by pressing enter.  Any ideas what might be causing this?


Java 8 method reference to class instance method NPE

import java.util.function.Function;  public class Playground {     public static void main (String[] args) {         Object o = null;         System.out.println(o);         Function<Object, String> toStringFunc = Object::toString;         String s = toStringFunc.apply(o);         System.out.println(s);     } }   This code will result in a NullPointerException being thrown, reported at the line containing toStringFunc.apply(o).  This is a trivial example, so it's easy to see that o == null, but how in general can we understand why this line of code would throw a NPE, as toStringFunc, the only variable being dereferenced in that line, is not null.


Get Exitcodes from WindowsForms Application in command window

I'm starting a Windows Forms application from the command promt and I need to get the exit codes that the windows forms application generates. The command promt starts the application and returns immediatly. But the application executes in the background. Is there a way to get the Exit codes?  Kind Regards  Christian.


To show $|(\mathbb{Z}/n\mathbb{Z})^{\times}| = \varphi(n)$

I know this question has been asked before, but this is (hopefully) not a duplicate. Dummit and Foote's Algebra asks us to show $$|(\mathbb{Z}/n\mathbb{Z})^{\times}| = \varphi(n)$$ using the following definitions, and nothing else:  $(\mathbb{Z}/n\mathbb{Z})^{\times} := \{\bar a \in \mathbb{Z}/n\mathbb{Z} : \exists \bar c \in \mathbb{Z}/n\mathbb{Z}, \bar a \bar c = \bar 1\}$  Here, $\bar a$ denotes the equivalence class of $a$ in $\mathbb{Z}/n\mathbb{Z}$, namely one of $\bar 0,\bar 1,...,\overline{n-1}$. $\bar a\bar c$ refers to the usual multiplication, i.e. we take any elements from the equivalence classes of $\bar a$ and $\bar c$, multiply them, and then reduce the result $\bmod n$. We have shown this works in an earlier proposition, i.e. modular multiplication is well-defined. So, $(\mathbb{Z}/n\mathbb{Z})^{\times}$ is just the collection of residue classes of $\mathbb{Z}/n\mathbb{Z}$ which have a multiplicative inverse in $\mathbb{Z}/n\mathbb{Z}$. $\varphi(n)$ is Euler's totient function, as is popularly known. It is not defined using $|(\mathbb{Z}/n\mathbb{Z})^{\times}| = \varphi(n)$ in this text. Rather it is defined as $\varphi(n) = |\{a\in\mathbb{N}: a\leq n, (a,n)=1 \}|$, i.e. number of positive integers less than and co-prime with $n$. $(a,n) = 1$ stands for $\operatorname{g.c.d}(a,n) = 1$. We have not yet shown that  $(\mathbb{Z}/n\mathbb{Z})^{\times} = \{\bar a \in \mathbb{Z}/n\mathbb{Z} : (a,n) = 1\}$  so please do not use this in your proof. Knowing this, it is trivial, but in a later exercise, we are supposed to prove this using $|(\mathbb{Z}/n\mathbb{Z})^{\times}| = \varphi(n)$ - so let's avoid circular arguments. Could someone please point me in the right direction? Thanks!


How to compress a file into zip format without having zip package installed? Pretty much what I need to do. I tried tar -czf loremipsum.zip but the format isn't a correct zip format when I try to uncompress it on windows. I'm limited and won't be able to install the package. Is there any work around?


Should I choose Web Site or Web Application?

When I want to start a new ASP.Net project in Visual Studio 2012 but I'm given the option to create an ASP.NET Web Application or an ASP.NET Web Site.  What's the difference between the two ASP.NET Web Application and ASP.NET Web Sites? I've developed Web Sites before but never tried a Web Application and would like to know more.


Why do some light bulbs remain on when the switch is off?

We have a situation in our bathroom where we can’t turn the lights off fully. If the switch is on, bulbs 1&2 are on. If switched off, bulb 3 is on. We’ve taken bulb 3 out for now but would like to correct the problem. Any suggestions? Diagrams very helpful.


I see minecraft seeds listed, and I started trying some of my own.  I have noticed using the same seed produces very similar styles of maps, i.e. start in a specific biome, very high mountains etc, but do they reproduce the maps exactly and you just spawn in the same place, or are they just a very specific set of rules for the area you first spawn?   If I have two maps of the same seed, and I walk 1000 blocks north, will the maps be identical/similar or totally random after the first spawn area?


I am new to using blender and have been watching youtube videos on how to use it. I copied the steps of how to create cracks in a surface. I can see what it looks like if it gets rendered but then when I go to render it I get the message "no render output node in scene". It's not an animation, it's just a single image. Here is a screenshot of all my nodes and the error after trying to get it to render.


I know how to create a view as a page or block and etc.  But The Displays seems meaning I can create lots of views?  This following is my guess:   Is it will group all kind of views to a single page? Does Displays just easily use the previous view configuration and just Put similar view together to manager easily?


Looking for a proof involving the Harmonic number

Prove that:  $\displaystyle \sum_{k=1}^{\infty} \frac{H_k}{k^q} = (1 + \frac{q}{2})\zeta(q + 1) - \frac{1}{2}\cdot \sum_{n=1}^{q-2}\zeta(k+1)\zeta(q-k)$  It looks tough just to start off with.   Any ideas on approach?


As of last night my Ubuntu 19.04 laptop won’t boot into its latest kernel. In the hours beforehand I had completed an apt-get upgrade and autoremove. The system continued along perfectly fine. After a reboot however, I reach an (intramfs) shell prompt.  Typing exit at this prompt I am then given the alert message:  ALERT! /dev/mapper/ubuntu--vg-root does not exist. Dropping to a shell!  I have discovered that I can successfully boot into an older kernel through the grub menu.  Latest installed kernel: 5.0.0-25-generic (not working  Backup kernel: 5.0.0-21-generic (working)  My system runs an LVM partitioned drive.  I found an old thread with the same symptoms that advised running ls /dev/mapper at the intramfs shell. All that returns is /dev/mapper/control  Any help would be greatly appreciated. Also, if there’s more info required please just let me know.  TIA


Java - Numbers aren't subtracting correctly?

So I've been starting to make a Cash Register program which will take in what the user is paying and how much the object costs.  This will tell the user how much coins (Toonies, loonies, etc.) they'll get in return.  Here's the part of the code that determines how much coins the user will get in return:  if(amountPayed >= amountToPay) {     remainder = amountPayed - amountToPay;      while(remainder > 0) {          if(remainder >= 2) {             toonies++;             remainder = remainder - 2;             System.out.println(remainder);         }          else if(remainder >= 1) {             loonies++;             remainder = remainder - 1;             System.out.println(remainder);         }          else if(remainder >= 0.25) {             quarters++;             remainder = remainder - 0.25;             System.out.println(remainder);         }          else if(remainder >= 0.1) {             dimes++;             remainder = remainder - 0.1;             System.out.println(remainder);         }          else if(remainder >= 0.05) {             nickels++;             remainder = remainder - 0.05;             System.out.println(remainder);         }          else if(remainder >= 0.01) {             pennies++;             remainder = remainder - 0.01;             System.out.println(remainder);         }      }   I've been having a problem with getting the correct amount, the loop ended up being infinite.  I thought to myself, this can't be true as I made sure that all the values would go through evenly.  I decided I should do some debugging so I made it output the remainder everytime it went through.  Here's what I got:  18.01 16.01 14.010000000000002 12.010000000000002 10.010000000000002 8.010000000000002 6.010000000000002 4.010000000000002 2.0100000000000016 0.010000000000001563 1.5629858518551032E-15   This was very weird to me because the numbers I entered only went to the second decimal.  I was subtracting the numbers from the remainder just fine.  So what's my problem?


Is there a way to find/track my plane's previous flight?

My current flight has been delayed 9 hours and the plane is nowhere in sight. The airline gives no information besides pushing back the departure date every few hours.  Is there an easy way to determine which flight should be arriving that's delayed so long?


How can I add JavaScript and CSS to my site?


I have recently started with a small company that is having pretty bad problems with mail ending up in peoples junk folders.   They used to send large bursts of newsletters from the one address every 2 months, but I have now convinced them to stop, and use MailChimp.  Ive checked our domain to make sure we are not Blacklisted anywhere and chased up with our mail service provider that we have reverse DNS and SPF set up.  I have started including Opt-Out options in newsletters to reduce the chance of more people marking them as junk.   But the problem seems to be persisting and we are not really in a position to keep on going like this, as several important mails are not arriving, even after people add us to their contacts.  So. onto the actual questions! Is there anything else that I can do to quickly repair our reputation, or reduce the risk of being flagged as spam?  Also, is there any credence to the suggestion to opt for a business package like those google offer? Would they make any difference to the problem?  Sorry for the wordy question!


If I block a 5/5 attacked with a 2/3 during my blocking step, could I then bounce my blocker with  and prevent it from being killed, while also having the 5/5 blocked? If so, why?


Images with absolute positions not working with overlay text

I'm trying to place an overlay text when hovered over an image but it's not working since the image is already in position absolute, so I can't use relative positioning. I tried to wrap them in a div but the image disappears and shifts from original location. Here's my code and screenshots:

This is a short description

     .image-2{     position: absolute;     margin-top: 3%;     left: 4%;     width: 30%; } .image-3{     position: absolute;     margin-top: 10%;     left: 30%;     width: 20%; } .image-4{     position: absolute;     margin-top: 30%;     right: 30%;     width: 30%; } .content {   position: relative;   width: 90%;   max-width: 400px;   margin: auto;   overflow: hidden; }  .content .content-overlay {   background: rgba(0,0,0,0.7);   position: absolute;   height: 99%;   width: 100%;   left: 0;   top: 0;   bottom: 0;   right: 0;   opacity: 0;   -webkit-transition: all 0.4s ease-in-out 0s;   -moz-transition: all 0.4s ease-in-out 0s;   transition: all 0.4s ease-in-out 0s; } .image-1{         position: absolute;         margin-top: 2%;         top: 0;         right: 0;         width: 35%;     } .content:hover .content-overlay{   opacity: 1; }  .content-details {   position: absolute;   text-align: center;   padding-left: 1em;   padding-right: 1em;   width: 100%;   top: 50%;   left: 50%;   opacity: 0;   -webkit-transform: translate(-50%, -50%);   -moz-transform: translate(-50%, -50%);   transform: translate(-50%, -50%);   -webkit-transition: all 0.3s ease-in-out 0s;   -moz-transition: all 0.3s ease-in-out 0s;   transition: all 0.3s ease-in-out 0s; }  .content:hover .content-details{   top: 50%;   left: 50%;   opacity: 1; }  .content-details h3{   color: #fff;   font-weight: 500;   letter-spacing: 0.15em;   margin-bottom: 0.5em;   text-transform: uppercase; }  .content-details p{   color: #fff;   font-size: 0.8em; }  .fadeIn-bottom{   top: 80%; }  How I display the images in absolute  Edit: As CBroe suggested positioning the wrapper instead of div worked.


Problem  I'm trying to sell the idea of organizational patch/update management and antivirus management to my superiors. Thus far, my proposition has been met with two responses:   We haven't had any issues yet (I would add that we know of) We just don't think it's that big of a risk.   Question  Are there any resources available that can help me sell this idea?  I've been told that 55-85% of all security related issues can be resolved by proper anti-virus and patch/update management but the individual that told me couldn't substantiate the claim. Can it be substantiated?  Additional Information  1/5 of our computers (the ones on the building) have Windows update turned on by default and anti-virus installed. 4/5 of our computers are outside corporate and the users currently have full control over anti-virus and Windows updates (I know this is an issue, one step at a time).


Part of simple proof of nontrivial center in p-group

I'm trying to understand the proof of a Burnside theorem (as stated in Beachy's Abstract Algebra p. 328): Let $p$ be prime number. The center of any $p$-group is nontrivial.  Now, In the proof they say that if we let $G$ be a $p$-group, then in the class equation $$|G| = |Z(G)|+\sum [G:C(x)]$$ for all $x$ that is not in the center and represent a conjugacy class, we see that every term in $\sum [G:C(x)]$ is divisible by $p$ since $x\not\in Z(G) \implies [G:C(x)]>1$. This last statement is what I do not understand, how do we know that $p \mid [G:C(x)]$ for any conjugacy class?  I know that the elements in the conjugacy class of $x$ is in bijection with the cosets of $C(x)$, i.e. $[G:C(x)]$, but how can we be certain that the number of elements in a conjugacy class of $x$/cosets of the centralizer of $x$ is divisible by $p$?  Best regards.


Examine rectified voltage before and after

I built a simple bridge rectifier.         – Schematic created using   I connected the output of the function generator with CH1 of my oscilloscope and  with the input of the rectifier (using a T-Piece). The output goes into CH2.   The original wave looks like this:    After connecting CH2 the picture looks like this:   While CH2 looks good,  CH1 now shows the wave I would expect without capacitator but not the expected original wave.   Could somebody explain why? I'm using a Gwinstek GDS-1072A-U Oscilloscope and a Gwinstek SFG-1003 function generator.


Why didn't Obi-Wan or Owen Lars change Luke's last name?

The novelization of Episode III makes it clear that Anakin was known as a galaxy-wide hero on the HoloNet, and that he had become a household name.  Why did Obi-Wan and Owen Lars, when making the handoff of Luke, change Luke's last name? Even on Tatooine, a lot of people would probably recognize the name Skywalker. Some especially curious people could have done some basic detective work and figured out additionally that Luke's guardians were related to Anakin Skywalker's family.


Why can't I increase to an outstanding bounty?

A friendly user placed a bounty on a question of mine:    The thing is, it's a pretty small bounty, and I want to augment it a bit. It doesn't seem I have an option of doing that; why?


Code for accessing windows registry throwing error

I have a chunk of code which is called at my application startup to find the ProgramData folder of the users PC and to create the application.log file for my app.  Problem is that in one of the users PC having windows 7, its throwing nullpoint error in the Java tracing pop up. I am not sure how to recreate or debug this issue, as this is the step to create the log file and put in ProgramData folder.  Any help is really appreciated!      final int HKEY_LOCAL_MACHINE = 0x80000002;     final int KEY_QUERY_VALUE = 1;     final Preferences systemRoot = Preferences.systemRoot();     final Preferences userRoot = Preferences.userRoot();     final Class clz = userRoot.getClass();     String appData = null;     try {         Method openKey = clz.getDeclaredMethod("WindowsRegOpenKey",                 new Class[] { int.class, byte[].class, int.class });         openKey.setAccessible(true);         Method closeKey = clz.getDeclaredMethod("WindowsRegCloseKey",                 new Class[] { int.class });         closeKey.setAccessible(true);         Method queryKey = clz.getDeclaredMethod("WindowsRegQueryValueEx",                 new Class[] { int.class, byte[].class });         queryKey.setAccessible(true);          int[] result = (int[]) openKey                 .invoke(                         systemRoot,                         new Object[] {                                 new Integer(HKEY_LOCAL_MACHINE),                                 toCstr("SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\Explorer\\Shell Folders"),                                 new Integer(KEY_QUERY_VALUE) });     int handle = result[0];     if(handle!=0){         byte[] bytes =(byte[]) queryKey.invoke(                 systemRoot,                 new Object[] {                         handle,                         toCstr("Common AppData")});         appData = new String(bytes,"US-ASCII");         closeKey.invoke(systemRoot,new Object[]{handle});     }     } catch (Exception e1) {         //log.error(e1.getStackTrace());     }


Adding number to a list and have it increase

I am having trouble storing multiple float values and adding them to a list to let it expand. I am getting the error "'float' object is not iterable"... while True:      #some code here      value_list = [value]     value_list.extend(value)     print("saving list", value_list)     print("max", max(price_list))      time.sleep(600)  value is scraping data from a website that I own with certain prices and it is converting it to float and the shared code is in a while True statement to show if the price changes overtime, then I want it to display the highest value from the stored list.


I've found ggmap's  function really useful over the years as it's got a 'fuzzy' search implemented by Google. However, I'm wondering if there are alternatives, because   geocode() seems unreliable sometimes overdependence on google it doesn't use/support open source API solutions   I've seen the   and  packages.   Has anyone else encountered this problem and discovered another solution, preferably using CRAN packages such as geonames?


Why is $\lim_{x\to\infty} \frac1x {x!}^{1/x} = \frac1e$?

I've tried various methods, but I couldn't get it equal to $\frac1e$. Please help!


What is sudo nautilus ? What does it do ? When do i use it?

Newbie here. I had to install adobe flash plugin and add it to firefox. I followed instructions of a youtube video and did that successfully. In one of the step it asked me to enter the command:   sudo nautlius.   I was wondering what does this particular step does and where else can I use it again?


I want to mess with , how do I get started?


"How long have you stayed there?" vs "How long did you stay there?"

I have a doubt about the difference between those two questions.  Could you guys give me an appropriate examples and explanation?  Thanks in advance!


How do I make a grid around all my points, and then convert it to a polygon

I want to make a grid around all my points, convert to a polygon and use this to clip the extent of my data. I am using Arc 10.2.  How do I make a grid and then convert it to a polygon? Or is there a way to miss some of these steps?


`console.log('Any way to format code in a question title?');`

I was just editing/improving a question and the original author had written a brief line of code in the title of their question.  Was just wondering if there may perhaps be some way to format the code.  I tried using backticks but that doesn't work.


How to center a node between two subtrees with `forest`?

I have the following tree, which I drew using the package forest:  \documentclass[border=2ex]{standalone} \usepackage{forest} \begin{document} \begin{forest} for tree={grow'=north, math content}     [u       [v_1]       [\cdots, no edge]       [f         [w_1]         [\cdots, no edge]         [w_m]       ]       [\cdots, no edge]% not centered :(       [g         [w_1']         [\cdots, no edge]         [w_n']       ]       [\cdots, no edge]       [v_k]     ] \end{forest} \end{document}    I hope my tree syntax is clear enough (it was originally a one-liner...). As you can see, the \cdots in the middle is not centered, which is what I would like. I'm not too certain how to approach this, as I'm sure there's something in forest that I do not know about which solves this problem for me. Could anyone point me towards a solution?  As a bonus, I would also be interested in understanding why this behavior occurs :)


Area51 SE is not available on the DE iOS app

Is there a reason for the fact that Area 51 is not available on mobile? Will Area 51 be available on the mobile version of the SE app soon?


What is the definition of rotation matrix?

From , it seems that rotation matrixes are orthogonal matrices with determinant 1. But is it definition of rotation matrix? I mean, are all orthogonal matrixes with determinant 1 rotation matrixes?


Period of oscillation through a hole in the earth

Special mention to the  that kicked this off:  Anyway, the host points out that a tunnel that connects a pair of points on the earth's surface can be thought of as a gravity train - where the force of gravity along the tunnel allows an object to fall through it and emerge on the other side. Any force perpendicular to the tunnel (in case the tunnel doesn't pass through the center of the earth) is ignored.   I worked it out and the equation is $a = -\frac{4}{3}\pi\rho G d$, where $d$ is the distance from the center of the tunnel and $\rho$ is the density of the earth.   Clearly, it is simple harmonic and therefore the period is constant and has no dependence on which two points were used to make the tunnel.   Does anyone have an intuition for why this should be the case? I imagine some Gauss' law type of argument should work here, but I cannot see it.  EDIT: More to the point, why even when the tunnel does not pass through the center, one obtains the same period. Is there any deeper explanation as to why this should be the case?


My worktops are treated with Danish oil, and I appear to have got some on the tiled splashbacks and not noticed until it's cured (it's not very obvious except in daylight, I oiled by artifical light).  Is there any way to get it off?  I don't want to use a blade until I've got an idea of how to get the residue off where the blade won't attack it.  It's not going sticky, so not a duplicate of .


How can I prove the maximum number of edges?

On my book it says that the maximum number of edges E, in a simply connected undirected unweighted graph $G(V,E)$ is $\dfrac{|V|(|V|-1)}{2}$.  How can I show that it is true? Thanks!


I wanna do a quick install into a usb that takes -60 minutes

I have a 32GB no-brand USB Flash drive, and I want to install the full Ubuntu onto it (excuse my bad English please); I'm trying to install it the right way (from a CD) but it is taking 6 hours, and I've just lost my patience. I need a way to just extract it on the USB as is, and to try it (like you'll do with any kind of portable software). Is there anything like this? And no, I'm not looking for the "live Ubuntu" I want "full Ubuntu"; and anyway, I'm planning to keep it on the same PC, not gonna use it on different ones.


$C$ is a square matrix and $\operatorname{tr}(C)=0$ are there matrices $A$ and $B$ in which $C=AB-BA$? I was thinking about the skew-symmetric matrix definition in which $A^T=-A$ so $a_{ij} = -a_{ji}$ .Anyways, I cannot sketch any sort of proof on a paper.


What is the title of this then future Cold War era book

I remember finding this book by chance on Wikipedia a long while ago. I'm writing a piece and want to reference this story.  In this book (published most likely around the 1970s and 80s) in the then future a Cold war divide became more intolerable. Someone has the idea to send a group of people (probably infants) out of Earth somewhere to isolate them from Earth to isolate them from the politics and cultures that fueled the war. The idea works. The resulting colony is a peaceful one with no attachments to any political ideology or religion on Earth. When explorers from Earth find this colony and try to make them join their cause it is an exercise of futility. No matter how much they try to convince them, the people of the colony can't fathom their logic. Through this exercise the explorers finally see their politics as nonsense and decide the rebel against their powers at be.  Two other things I remember about this book is that in it America became a dictatorship and that the author was inspired by the Troubles in Northern Ireland.  I have tried to look it up on Google, but only get junk, like "50 sci-fi stories you must read" and so on.


Installing a new HD purchased from ebay, would like to test it first. What is the best way to test it?

Installing 2Tb hybrid SSD/HD into Thinkpad T430. Bought it from ebay, not sure if NIB or ??? would like to test it before loading it up with Ubuntu 20 LTS. (Beginner) Currently running Ubuntu 16.04 LTS, I downloaded 20 and put it on a USB, it runs fine, AFAIK. No dual boot for the new install.


C++ what happen during 'object slicing' when casting derived class to base class

When I tried to assign a derived class object to a base class, the 'unique' part in the derived class will be sliced down. So what happen to those part that being sliced away?  Are they destroyed properly or they are just lost in memory? And if I alloc some memories on those derived part, when the object slicing happen, will the alloced memories be freed properly? I suppose it will lead to some undefined behavior, since we never declare an approach to destroyed those derived parts when object slicing.  And after all, what's a situation that we need to use object slicing? Or we should always avoid that ?


Child meta move makes the Stack Exchange app blow up

The child meta sites have been renamed for the move to https. As a side effect their names in the API changed, making the favorite sites in the app display "unknown site" in the list.  So far so good. Clicking that entry results in the standard crash message (Stack Exchange stopped working) and the app restarting.


When I look at  I see “26 Suggestions”:    When I look at the detail of any suggestion, and click on More, I get Editor Stats which says “Bill Woodger had 16 edit suggestions approved, and 11 edit suggestions rejected”:    The profile appears to be counting one less suggested edit than the sum of approved and rejected suggested edits. Why is the count different? In looking around, I noticed that suggestions on deleted posts are not removed. Might it be a deleted user? Or something else?  As can be seen from @animuson's Answer, I misunderstood the post I referred to (link in the comments). Although the Suggested Edit itself is not deleted, it is removed from my (or whoever's) list of Suggestions.


Why hasn't Music.SE's name changed on data.stackexchange?

Recently (~ November 6th), the name of Musical Practice and Performance was changed to Music: Practice & Theory.*  But, on data.stackexchange has not changed yet:    Will it be changed?  *


Replacing bibliography icons in beamer with biblatex bibliography

shows how to use a user-defined icon when using the thebibliography environment. How can I redefine the icons if I use \printbibliography from biblatex?  Edit:  In the answer I linked to, each bibliography item is set manually, and so you can add   \setbeamertemplate{bibliography item}{\includegraphics[width=1.5em]{ctanlion}} \bibitem{A} CTAN lion drawing by Duane Bibby.   in front of each seperate entry if you wanted to. With \printbibliography the whole bibliography is typeset. So if I were to say  \setbeamertemplate{bibliography item}{\includegraphics[width=1.5em]{ctanlion}} \printbibliography   it would appear in front of the bibliography as a whole, not even in front of the first entry.


should i install ubuntu 14.04 or wait for 15.04

my question as the title said, should I install Ubuntu (14.04.2 LTS) now ? Or should I wait for the 15.04 ?  Thanks for answering!


Why is $\operatorname{spec}(K[x,y])-\{(x,y)\}$ not isomorphic to $\operatorname{spec} K[x,y]$

Why is $\operatorname{spec}(K[x,y])-\{(x,y)\}$ not isomorphic to $\operatorname{spec}K[x,y]$? I cannot see why they can't be an isomorphism between? If both of these are infinite sets there can be a bijection between them. I might be missing some trivial argument, any help is appreciated. I was trying to prove $\{A_k\}^{2}-\{(x,y)\}$ is not affine and I complete the argument if I am able to show the above claim.


Why is Entity Framework including square brackets in my column name? '

I am working through a (simple)  in a Console Application just to learn the basics of Database Migrations in EF. All of the other Tables and Columns are being generated fine but this one Column is being created with angle brackets around it in SQL Server Express ( '[Content]' rather than 'Content').  I can't see any thing in the class declaration   public class Post     {         public int PostID { get; set; }         [MaxLength(200)]         public string Title { get; set; }         public string Content { get; set; }          public int BlogID { get; set; }         public Blog Blog { get; set; }      }   the Migration file   public partial class AddPostClass : DbMigration {     public override void Up()     {         CreateTable(             "dbo.Posts",             c => new                 {                     PostID = c.Int(nullable: false, identity: true),                     Title = c.String(maxLength: 200),                     Content = c.String(),                     BlogID = c.Int(nullable: false),                 })             .PrimaryKey(t => t.PostID)             .ForeignKey("dbo.Blogs", t => t.BlogID, cascadeDelete: true)             .Index(t => t.BlogID)             .Index(p => p.Title, unique: true);          AddColumn("dbo.Blogs", "rating", c => c.Int(nullable: false));     }      public override void Down()     {         DropForeignKey("dbo.Posts", "BlogID", "dbo.Blogs");         DropIndex("dbo.Posts", new[] { "Title" });         DropIndex("dbo.Posts", new[] { "BlogID" });         DropColumn("dbo.Blogs", "rating");         DropTable("dbo.Posts");     } }   or in the generated SQL script (I used the -Verbose flag)  CREATE TABLE [dbo].[Posts] ( [PostID] [int] NOT NULL IDENTITY, [Title] [nvarchar](200), [Content] [nvarchar](max), [BlogID] [int] NOT NULL, CONSTRAINT [PK_dbo.Posts] PRIMARY KEY ([PostID])   )  which would indicate why this particular column is being generated with the angle brackets included?  Can anyone help?


What does 'without password' mean in sshd_config file?

I just installed Ubuntu 14.04 on my server and I was setting up all my config files when I came across this in my sshd_config file:  # Authentication: LoginGraceTime 120 PermitRootLogin without-password StrictModes yes   This made me very worried. I thought that it was possible that someone could be logging into my server as root without a password.  I tried connecting to my server as root via:  johns-mbp:~ john$ ssh root@192.168.1.48 The authenticity of host '192.168.1.48 (192.168.1.48)' can't be established. RSA key fingerprint is 40:7e:28:f1:a8:36:28:da:eb:6f:d2:d0:3f:4b:4b:fe. Are you sure you want to continue connecting (yes/no)? yes Warning: Permanently added '192.168.1.48' (RSA) to the list of known hosts. root@192.168.1.48's password:     I entered a blank password and it didn't let me in, which was a relief. So my question is: what does without password mean and why is this a default in Ubuntu 14.04?


This query is returning multiple results.  In the bottom you can see there are two of each id number.  How do I distinct records where I still get 25 records of unique values?          SELECT *             FROM(                 SELECT                     DISTINCT cards.id, cards.name, cards.created_at, cards.updated_at                     FROM cards                         INNER JOIN card_process                             ON card_process.card_id = cards.id                             INNER JOIN processes                                 ON processes.id = card_process.process_id                                 INNER JOIN category_process                                     ON category_process.process_id = processes.id                                     INNER JOIN categories                                         ON categories.id = category_process.category_id                                         INNER JOIN series                                             ON series.id = categories.serie_id                                             INNER JOIN serie_user                                                 ON serie_user.serie_id = series.id                         AND `cards`.`type` NOT IN ('', 'libraries')                         AND NOT `cards`.`deleted`                         AND NOT `categories`.`deleted`                         AND NOT `series`.`deleted`                         AND `cards`.`type` IN ('forms')                         AND `series`.`id` IN (124,235,126,126,201,236,207,207,207,207,247,234,131,131,221,225,225,222)             UNION ALL                 SELECT                     DISTINCT cards.id, cards.name, cards.created_at, cards.updated_at                     FROM cards                         WHERE `cards`.`account_user_id`='9'                             AND NOT `cards`.`deleted`                             AND `cards`.`type` IN ('forms')             ) AS qry                 ORDER BY `updated_at` ASC                 LIMIT 0, 25


Does Time machine backup apps data and OS configuration?

Does Time machine backup apps data and OS configuration or just apps and files?  Coming from Windows with a 3rd party full disk image backup(Note :I mean a disk clone, not the Windows' default backup an restore and functionality) , I would expect to be able to use time machine to restore the mac as it was in the moment I made a time machine backup.  I am honestly not aware how apps store data on MacOS though


Simple Bayesian classification has me discouraged

My university is testing an intro Machine Learning (ML) course for us undergrads, and having been interested in ML since the beginning to understand what it was, I jumped at the chance to take it. But being someone who has not been back in school for a long time and much busier than I was in my first years long ago, I am finding that I need more info and examples than the class in its current form has. I am struggling to figure out what the attached question is asking. I am searching online for help with this particular topic, but I am also finding that everyone seems to have their own way of phrasing similar questions in such a way that I am finding it hard to link the info.  My understanding from stats way back when is that p(x|ω1) p ( x | ω 1 )  is stating the probability of x x  given ω1 ω 1 for 0≤x≤2 0 ≤ x ≤ 2  and zero other wise. Same obviously if given ω2 ω 2 . If I understand, the priors are the probability of ω1 ω 1  and ω2 ω 2  which are somehow obtained. And honestly that is as far as I am really comprehending. I am not sure what (a) and (b) are truly asking for or how to get them. If anyone is able to help me with some pointed info on the topic it would be greatly appreciated.


I am writing a cross-platform library for my own use. The library can be used in linux kernel, NT kernel, and many other environments, so I don't want to be dependent on any headers or libraries, even if they are standard headers. So, I cannot include stdint.h to use int32_t.  If I use VC++, I can typedef __int32 MY_INT32;, because __int32 is built in the compiler.  Is there a counterpart of __int32 in GCC?  My current practice is:  typedef signed char        KTL_INT8; typedef signed short       KTL_INT16; typedef signed int         KTL_INT32; typedef signed long long   KTL_INT64; typedef unsigned char      KTL_UINT8; typedef unsigned short     KTL_UINT16; typedef unsigned int       KTL_UINT32; typedef unsigned long long KTL_UINT64;  static_assert(1 == sizeof(KTL_INT8),  "sizeof(KTL_INT8) != 1"); static_assert(2 == sizeof(KTL_INT16), "sizeof(KTL_INT16) != 2"); static_assert(4 == sizeof(KTL_INT32), "sizeof(KTL_INT32) != 4"); static_assert(8 == sizeof(KTL_INT64), "sizeof(KTL_INT64) != 8");


Where are the slaughter arenas in the game and which one can I get to the earliest? I just finished the part where Sanctuary lifts off.


Force create nonexistent directory via vi or touch?

There are -p option in mkdir command to create parent directories as needed wolf@linux:~$ tree .  0 directories, 0 files wolf@linux:~$  wolf@linux:~$ mkdir dir1/dir2/dir3 mkdir: cannot create directory ‘dir1/dir2/dir3’: No such file or directory wolf@linux:~$  wolf@linux:~$ tree .  0 directories, 0 files wolf@linux:~$  wolf@linux:~$ mkdir -p dir1/dir2/dir3 wolf@linux:~$  wolf@linux:~$ tree  . └── dir1     └── dir2         └── dir3  3 directories, 0 files wolf@linux:~$   Are there similar features in vi or touch command? In this case, I would like to create file authorized_keys in nonexistent directory .ssh with vi or touch. authorized_keys is a file, and not a directory. Hence, mkdir -p .ssh/authorized_keys command is not applicable here as authorized_keys will be created as directory, not a file. wolf@linux:~$ ls .ssh ls: cannot access '.ssh': No such file or directory wolf@linux:~$   Would it be possible to do this without mkdir .ssh or mkdir -p .ssh? wolf@linux:~$ touch .ssh/authorized_keys touch: cannot touch '.ssh/authorized_keys': No such file or directory wolf@linux:~$


I came across an answer that we can check if number is between a given range by following method 10<=n<=100. I want to know how exactly this statement gets executed in python.I'm new to python and know how to code in java.  From the answers, I came to know that this feature is called chaining comparison operators. Thanks a lot for answers.


I was looking at   and I wondered if the following could be done from terminal. I did it in python, just want to see if it could be done from terminal, bash scripting or whatever.  Suppose I have a file that looks like so:  2,4,5,14,9 40,3,5,10,1   could it be sorted like so, by rows (lines)  2,4,5,9,14 1,3,5,10,40   or is it too complicated? I did it using python, I just want to know if it could be done so next time I might not use python. What I have done, is creating lists and sorting them.


Is there a way to boot from a USB on a MacBook Pro with disc drive?

I know that on certain models of MacBook you can only install Windows from the SuperDrive—is there a way to circumvent this limitation? My computer is a MacBook Pro 13" from 2010, it doesn't have a disc drive and I want it to boot from a USB with Windows.


How to prove that $\max\{f,g\}$ is Riemann integrable?

If f(x) and g(x) are Riemann integrable in [a,b], why $h(x)=\max\{f(x),g(x)\}$ is still  Riemann integrable in [a,b]?  Or maybe it is wrong?


Are Macs vulnerable to the Bash shellshock bug?

Red Hat recently  in the Bash shell. Some are calling it the "shellshock" bug. Since OS X is built off of Unix, is it vulnerable to attacks that exploit this bug?   As an end user, do I need to worry about an immediate fix? Or is it better for me to wait for an official software update from Apple?


I'm just curious about whether it is possible to build an ideal hexadecapole (16-pole) from point charges in 3D.  My intuition tells me no, because the point charge of a (electric) monopole "bound" a 0-dimensional region (a point), the 2 charges of a dipole bound a 1-dimensional region (a line segment), and so on (see picture below for magnetic multipoles, though I'm actually asking about either magnetic OR electric multipoles).  Then it seems like the highest dimensional object we could construct in 3D is a octupole.    But I didn't use any math (or really physics either) to make my conjecture.  So is there a way to prove that I'm right or is there actually a way to construct an ideal hexadecapole in 3-space?


Capturing multiple line output into a Bash variable

I've got a script 'myscript' that outputs the following:  abc def ghi   in another script, I call:  declare RESULT=$(./myscript)   and $RESULT gets the value  abc def ghi   Is there a way to store the result either with the newlines, or with '\n' character so I can output it with 'echo -e'?


Installed Ubuntu Studio, got standard version

I tried to install 13.04 alongside with Windows 7, but it completely fails and just reboots.  So now I tried to install 12.10, which I have had previous success, fail.  I ran the demo and it worked just fine. It was exactly what I expected.  I used Wubi in Win 7 to install Ubuntu Studio, everything seemed fine until I restarted and was booted into Ubuntu 12.10, not Studio.  I have none of the production software, and the interface is completely different.  How can I get the version of Ubuntu Studio?


I have no idea how to do this question. If you have a loaded dice such that the probability to obtain an outcome of 1 is 2p/3, the probability of obtaining 2, 3, 4 or 5 is p each, and the probability of obtaining 6 is 3p/2. Find p.   Any help would be much appreciated!


Share Document Root for Apache w/ SSL with two separate subdomains and certs

So, I'm running an Apache server on CentOS 7. I have two domains pointing to the same place:  and . In my cfg, I have three VirtualHosts; one for http (for both) one for the subdomain-less, and one for the www. I have the separate certs configured (one for each), but when I deploy, Apache just serves up the first cert it finds in the cfg. So if I have the VirtualHost for www first, it serves up the www cert for both  and   I have other domains being served on the same box and they get all the right certs.  Can somebody please explain what is going on here? It's driving me absolutely   # Abbreviated Main config file for example.com domain <VirtualHost *:80>    ServerAlias example.com   ServerAlias www.example.com    DocumentRoot "/var/www/example.com"  </VirtualHost>  <VirtualHost *:443>   ServerAlias example.com      DocumentRoot "/var/www/example.com"    SSLEngine on   SSLCertificateFile "/etc/letsencrypt/live/example.com/fullchain.pem"   SSLCertificateKeyFile "/etc/letsencrypt/live/example.com/privkey.pem"  </VirtualHost>  <VirtualHost *:443>   ServerAlias www.example.com    DocumentRoot "/var/www/example.com"    SSLEngine on   SSLCertificateFile "/etc/letsencrypt/live/www.example.com/fullchain.pem"   SSLCertificateKeyFile "/etc/letsencrypt/live/www.example.com/privkey.pem"  </VirtualHost>


Counting 2-partitions of $\{1, 2, \cdots, n\}$ of equal size and sum

The following question solves the existence of such a partition: . However, I'm trying to count how many such 2-partitions exist. Specifically,  Let $X = \{1, \cdots, 2n\}$. How many unique $S \subset X$ has cardinality $n$ and $\sum S = 2n^2+n$?  I'm trying to count the number of exact sequences on finite dimensional vector spaces $\mathbb R^1, \cdots, \mathbb R^{2n}$.


Where can I find information about past versions of iOS and code-signing windows?

I have an iPad 2 that is currently running iOS 5.0.1. I'm generally happy with it but some applications require a more recent iOS version. So I started to look into upgrading it, but the only upgrade that it offers is to iOS 7.  From the look of it I don't like the new design of iOS 7 too much and also upgrading to a version this fresh doesn't appeal to me. So my question is: is there a way to upgrade to some version of iOS 5.x or iOS 6.x instead of upgrading to iOS 7?


I'm using PHP. I want a safe and fast password encryption system. Hashing a password a million times may be safer, but also slower. How to achieve a good balance between speed and safety?  I want to know the best encryption method in php and how to apply it.


"Items cannot be installed or removed until the package catalogue is repaired."

I just installed Ubuntu 12.04 over 10.04. It seemed to go OK until I tried running my updates. When I launch Software Center I get the following error message:  Items cannot be installed or removed until the package catalogue is repaired. Do you want to repair it now? Once Update Manager has finished the repairs, you can close it and return to the store.  So I hit repair and then I get this message:  Package operation failed The installation or removal of a software package failed.  So I hit OK and it goes back to the first error message And it just continues repeating those two messages. How do I fix whatever is broken? I reviewed answers for similar questions. I tried the suggestions in that link but they did not work. I tried to post the results but, being new to this system I am not allowed to post more than 2 links. However, it seems the crux of the problem is this: (Reading database ... 742676 files and directories currently installed.) Removing libxml-libxml-perl ... /var/lib/dpkg/info/libxml-libxml-perl.prerm: 11: /var/lib/dpkg/info/libxml-libxml-perl.prerm: update-perl-sax-parsers: not found dpkg: error processing libxml-libxml-perl (--remove):  subprocess installed pre-removal script returned error exit status 127 Errors were encountered while processing:  libxml-libxml-perl E: Sub-process /usr/bin/dpkg returned an error code (1)


Does Windows log programs that have been run/called?

In Windows, is there a log that records what programs were run/called?  While browsing the internet, viewing a static page with no ads, mouse clicks, keypresses, or miscellaneous plugins/addons/scripts running, I just saw a spontaneous CMD.exe console pop open and then immediately close in a flash, fast enough that I wasn't able to see anything in the window -- and with no apparent triggering on my part.  I'm wondering if there is some type of Windows log that shows what programs have been run/called/activated? I'd like to see what was happening behind the scenes when this console window flashed, and hopefully determine it wasn't something rogue.  For reference, I'm running Windows 7 Ultimate x64.


Given $a>b>2$ both positive integers, which of $a^b$ and $b^a$ is larger?  I tried an induction approach. First I showed that if $b=3$ then any $a \geq4$ satisfied $a^b<b^a$.  Then using that as my base case I tried to show that given any pair of positive integers $a,b$ satisfying $a>b>2$ and $a^b<b^a$, then $(a+1)^{b+1}<(b+1)^{a+1}$ - but that is where I got stuck.  Any help would be appreciated.


How do I compute $\int_{-\infty}^{\infty}x^2e^{-x^2}dx$?

I arrive at the partial solution of $((x*e^{-x^2})/2)- (\pi^{1/2}/2)$ using double integration by parts.  How do I resolve the first part of the solution with e.  Is the solution even right?


I am a bit confused about these two forms For example :  John reads books all of the time/all the time All the students/All of the students have participated in march against smoking in the campus  are they both correct? or it depends on the context?


I' am getting the following characters on my website contact us form. How can I validate the message field so that such characters are not allowed.  Ð”Ð¾Ð±Ñ€Ñ‹Ð¹ Ð´ÐµÐ½ÑŒ! ÐžÐºÐ°Ð·Ñ‹Ð²Ð°ÐµÐ¼ Ð¿Ð¾Ð¼Ð¾Ñ‰ÑŒ Ð² Ð¿Ð¾Ð»ÑƒÑ‡ÐµÐ½Ð¸Ð¸ Ð³Ñ€Ð°Ð¶Ð´Ð°Ð½Ð°Ð¼ Ð¸ ÑÐ¾Ñ‚Ñ€ÑƒÐ´Ð½Ð¸ÐºÐ°Ð¼ Ñ„Ð¸Ñ€Ð¼ ÐºÐ°Ñ€Ñ‚Ð¾Ñ‡ÐµÐº Ð¼ÐµÑ‚Ñ€Ð¾ Ð² ÑÐµÑ‚ÑŒ Ð½ÐµÐ¼ÐµÑ†ÐºÐ¸Ñ…   This is the code am currently using  $message = sanitize_text_field($message); $message = str_replace("`","", $message);


Is there any documentation / definition of the operations within, crosses, intersects etc that can be found on the spatial query just like ArcGIS provide?


what is the advantage of declaring instance variable of collection (list, map) as final in java

What is the point of declaring instance variable as final  final List<Integer> intList = new ArrayList<Integer>();


I am a windows user, and I don't know nothing about Ubuntu and how does it works. I don't know how to access my computer, I don't know how to access command prompt nothing.   Just now I installed Ubuntu 14.04 LTS, due to wifi problem I reinstalled Ubuntu and now the wifi is working fine.   Now I am not able to install any of the exe file. I am trying to install file zilla,internet download manager, 7zip, and as a blogger I would like to install some other blogging related tools which install on Adobe Air.   Can any one please help me and instruct me in detail step by step on how to install wine on Ubuntu 14.04.   Or are there any other programs which makes to install windows related applications.


Prove that $\lim_{x\to\infty} f'(x) = 0$

Let $f(x)$ be twice differentiable on $(0,\infty)$ and let $\lim_{x\to \infty} f(x) = L<\infty$ and $|f''(x)| \le M$ for some $M>0$.  Prove that $\lim_{x \to \infty} f'(x) = 0$.  I've tried to use taylor with remainder in a lot of different ways and am still unable to crack this one.


Should I delete my own chatroom when done?

I opened up my first chatroom for help on a question. It can be found . Now I'm wondering, is it my responsibility to delete the chatroom? What is the proper etiquette?


How to enable Internet Connection Sharing using command line?

I can do it manually by right-clicking on a network connection, opening the Sharing tab and clicking on the "Allow other network users to connect through this computer's Internet connection" check box.  Now I need to automate this task. Is there a command-line tool or a Powershell cmdlet to accomplish this?


How can i round some vertex on a flat object?

I created this object but i want to make it round at the top like the screenshot. How can i make it? I know that bevel is one option but i am not sure how to use it in this object since it's flat.   Update: I created those cuts, how can i make them into a round shape now?


Showing that $[0, \omega_1]$ is compact.

I want to show that $[0, \omega_1]$  is compact, where $\omega_1$ is the least uncountable ordinal, and I have just been introduced to the concepts of ordinals.   The tips I have seen to showing this is that $[0, \omega_1]$:   contains a maximal element there are no infinite strictly decreasing sequences of ordinals.     Take an open cover of the desired set. My thoughts are that some open set must contain $\omega_1$, which in turn contains all ordinals smaller than it by the definition of an ordinal, and so this open set is a cover of the entire space. Any further insights appreciated.


Does non-mass-energy generate a gravitational field?

At a very basic level I know that gravity isn't generated by mass but rather the  and when I wave my hands a lot it seems like that implies that energy in $E^2 = (pc)^2 + (mc^2)^2$ is the source of gravity.  If the total energy of a particle contributes to the generation of a gravitational field, that seems to imply some strange things.  For example, you could accelerate a particle like an electron to such a high velocity that it has enough momentum / kinetic energy to collapse into a black hole.  An observer traveling with the electron would see an electron and stationary observers would see an arbitrarily massive black hole flying by.  These observations seem to be contradictory.  The same would be true of an extremely high energy photon.  Another consequence is that a stationary particle could appear to have so much mass that it could attract / deflect the trajectory of a rapidly moving observer.  It seems odd that at low velocities you wouldn't even notice a stationary electron as you pass it by but at high velocities the gravitational field you observe could be significant enough to alter your path.  Am I correct that non-mass-energy generates a gravitational field?  If it does, how are these strange observations like a particle looking like a black hole in one reference frame but not another reconciled?


Why does C++11 brace initialization work with stack-based class hierarchies?

I'm playing around with C++11 and I've compiled the below successfully on Mac OS X using c++ -std=c++11 main.cpp.  #include <iostream> #include <vector> #include <string> using namespace std;   class s { public:     s(const string& str) : value {str} {}     string value; };  class t : public s  { public:     t(const string& str) : s{"t: " + str} {} };  int main(int argc, const char** argv) {      vector<s*> ss1     {         new s { "hello" },         new s { "there" }     };      vector<s> ss2     {         s { "greeting" },         s { "father" }     };      vector<s> ss3     {         { "ahoy" },         { "matey" }     };      vector<s> ss4     {         { "bonjour" },         t { "mademouselle" }     };      for (auto &s : ss1) {         cout << "value: " << s->value << std::endl;     }      for (auto &s : ss2) {         cout << "value: " << s.value << std::endl;     }      for (auto &s : ss3) {         cout << "value: " << s.value << std::endl;     }      for (auto &s : ss4) {         cout << "value: " << s.value << std::endl;     }  };   The output is here:  value: hello value: there value: greeting value: father value: ahoy value: matey value: bonjour value: t: mademouselle   The thing that I don't understand is that ss4 is simply a vector<s>, and yet I am able to store the derived class t inside of it. How is this possible?


Diamond moderator privileges vs. 10k rep privileges?

As we are in election period, I don't get the difference between getting to 10k reputation point and the diamond. What additional controls do you earn with the diamond ?


resetPassword problem for enterprise users when called from a community?

I'm working within a custom application in a customer community that is used by both community-license users and Salesforce enterprise users.  There is a custom Visualforce page where an application admin can select a user and reset the password.  The VF Controller is using the standard System.resetPassword() method.  We are finding that when an enterprise user receives this password reset email, the user can't get to the expected password reset page.  Instead, it eventually redirects to the community login screen.  The password reset URL for these enterprise users is based on the community's URL, and it seems that these users cannot change password through the community -- it has to be through the enterprise URL, like what you get when you reset password via Setup.  Has anyone run into this and found a workaround?  (Of course community users have no trouble with password resets through this Visualforce page.)