How to find limit of function: $\lim_{x\to 0}\left(x{{\left\lfloor{ \frac{1}{x}} \right\rfloor}}\right)$

Find $\displaystyle \lim_{x\to 0}\left(x{{\left\lfloor{ \frac{1}{x}} \right\rfloor}}\right)$.   When $x\to0^{+}$ I have  $\left(x{\left\lfloor{ \frac{1}{x}} \right\rfloor}\right)\to 0\cdot \infty$.  When $\to 0^{-}$ I have  $\left(x{\left\lfloor{ \frac{1}{x}} \right\rfloor}\right)\to 0\cdot \infty$.  I have no idea,


I've tried so many different websites trying to find cheap lightroom film emulations.  I'd like to achieve looks like these:


Combinatorics Identity about Catalan numbers: $\sum_{k=0}^n \frac{1}{k+1}\binom{2k}k \binom{2n-2k}{n-k}=\binom{2n+1}n$

I need to prove this identity:  $\sum_{k=0}^n \frac{1}{k+1}{2k \choose k}{2n-2k \choose n-k}={2n+1 \choose n}$  without using the identity:  $C_{n+1}=\sum_{k=0}^n C_kC_{n-k}$.  Can't figure out how to.


Is it possible to find the present index in an enhanced for loop? If so how?  I am aware we can check it with an extra variable. But is there any other way.  public boolean cancelTicket(Flight f, Customer c) {     List<BookingDetails> l = c.getBooking();     if (l.size() < 0) {         return false;     } else {         for (BookingDetails bd : l) {             if(bd.getFlight()==f){                 l.remove()  // Index here..             }         }     } }


Are the following sentences correct?   1) They were dating for the longest time but then they broke up, because she cheated on him.   2) I've gone grocery shopping this morning.   3) I had never thought about it vs I have never thought about it. (which one is correct and why)   4) When I introduced my dad to my friend, they just laughed, and said they had already met each other/they have already met each other. (the second option sounds correct to me, but I would use present perfect rather than past perfect)  If there is the possibility to use both, please write some examples. It would be really really helpful.


GAP: how to work with elements of the group ring of the symmetric group $\mathbb{C}[S_k]$?

In GAP, working with elements of the symmetric group $S_k$ is straightforward. E.g. one can write  (1,2)*(2,3);   to obtain (1,3,2).  Is there a similar functionality to work with group rings, say $\mathbb{Q}[S_k]$? E.g., what would be the standard approach to evaluate expressions such as  [3*() - (1,2)] * [-(1,2) + 1/3*(2,3)]   I'm aware that one can create $\mathbb{Q}[S_k]$ by   G:= SymmetricGroup(k); KG:= GroupRing(Rationals, G);   After that step however I don't know how to create actual elements of $\mathbb{Q}[S_k]$.


Where did the Slytherin house go during the Battle of Hogwarts?

Now when the Slytherin students were able to escape, they were running and shouting, except for Goyle and Zabini who are grabbed by Malfoy.  Where did the House go afterwards? Did they fight the Death Eaters?


Suppose $\sum{a_n}$ converges. How do I prove that $\sum{\frac{\sqrt{a_n}}{n}}$ converges.  So I know that just because  $\sum{a_n}$ converges, do not mean I can say anything about the converges of its square root. So I know that I can prove that if  $\sum{\sqrt{a_n}}$ converges then $\sum{\frac{\sqrt{a_n}}{n}}$ converges by Abel's Test, but I do not know where to start for the case where  $\sum{\frac{\sqrt{a_n}}{n}}$ diverges


Background:  I want to travel to the USA.  I have dual citizenship (British + Brazilian).   I haven't applied to ESTA with British passport yet because I have B1/B2 Visa in the Brazilian passport valid until 2025.  I'm buying the ticket using British passport as I'm flying from the UK.  Question:  Can I enter the USA with Brazilian passport?


What packages do I need for ubuntu to read a bluray?

I have tried installing various packages suggested online such as libaacs0 libbluray-bdj and libbluray1. WIth these packages, ubuntu is not not able to read a bluray disc.


How to take ScreenShot & save it with different filenames by using Selenium & Java?

I have created screenShot() method to take the screenshot of the web page. When I used this method in my code first time it will capture the screen and it will save the image with image1 name. When I used the same method screenShot() to capture screens for other pages with the use of this.screenShot(); this will again capture the current web page screen but it stores With the same name image1 in the same folder (which overrides to previously captured screen image1).  Now, I have to take screenshots for the number of web pages & want to store it into the same folder with different names like image1, image2, image3...etc. by using the same method screenShot().  public void screenShot() throws IOException, InterruptedException {     File scr = ((TakesScreenshot)driver).getScreenshotAs(OutputType.FILE);     File dest = new File("filPath/image1.png");     FileUtils.copyFile(scr, dest); }   Any workaround to achieve this scenario?


OS X Terminal not recognizing any commands

I recently tried to install CoffeeScript on my mac and now am unable to use even the most basic of commands like ls, cd and so on. Something tells me that it's because the $PATH variable has changed. I remember having to do that when I tried to make the installation. I tried following the instructions found , but it doesn't work because the vi command isn't found.  Upon entering echo $PATH in the terminal, it reads /usr/local/bin:


Uni assignment requires that we build a pizza app in C# that derives Sauce from Ingredient. I have a List<Ingredient> that is storing objects of both types.  Pizza.cs calls the method GetInstructions() which is slightly different in the derived method. Unfortunately Sauce.GetInstructions() is never being called. As you can see, there's a debug line in there that should pop up a message box when the program is executing that routine but it's not popping up. Can anyone suggest why not?  Pizza.cs contains the following method:  public string BuildInstructionList()     {   // iterate through list of selected toppings and build a single string for display in the GUI     int count = 1; string instructions = "";     foreach (var i in toppings)         {         instructions = instructions += string.Format("Step {0}: {1}", count, i.GetInstructions());         count++;         }         return instructions;     }   Ingredient.cs contains:  public virtual string GetInstructions()     {         string instructionLine;         string qty = this.GetIngredientQuantity().ToString();         string unit = this.GetIngredientUnit();         string name = this.GetIngredientName();         instructionLine = string.Format("Add {0} {1} of {2} to the pizza.\n", qty, unit, name);         return instructionLine;     }   Sauce.cs contains:  public new string GetInstructions()     {         PizzaGUI.Message("I am here!");         string instructionLine;         string qty = this.GetIngredientQuantity().ToString();         string unit = this.GetIngredientUnit();         string name = this.GetIngredientName();         instructionLine = string.Format("Apply {0} {1} of {2} to the pizza.\n", qty, unit, name);         return instructionLine;     }


Ubuntu not finding file (permission 755)

Running ubuntu 15.10 64 bit. Extracted oracle's jdk and was trying to run java. Permission look ok, but why is it not finding java executable -  raj@raj-VirtualBox:~/jdk1.8.0_74/bin$ ./java -version bash: ./java: No such file or directory raj@raj-VirtualBox:~/jdk1.8.0_74/bin$ ls -l | grep java -rwxr-xr-x 1 raj raj   5730 Jan 29 22:08 java -rwxr-xr-x 1 raj raj   5881 Jan 29 22:08 javac -rwxr-xr-x 1 raj raj   5889 Jan 29 22:08 javadoc -rwxr-xr-x 1 raj raj   2293 Dec 22 15:58 javafxpackager -rwxr-xr-x 1 raj raj   5881 Jan 29 22:08 javah -rwxr-xr-x 1 raj raj   5881 Jan 29 22:08 javap -rwxr-xr-x 1 raj raj   2293 Dec 22 15:58 javapackager -rwxr-xr-x 1 raj raj   1809 Jan 29 22:08 java-rmi.cgi -rwxr-xr-x 1 raj raj 104523 Jan 29 22:08 javaws raj@raj-VirtualBox:~/jdk1.8.0_74/bin$ java -version bash: /home/raj/jdk1.8.0_74/bin/java: No such file or directory raj@raj-VirtualBox:~/jdk1.8.0_74/bin$ javac bash: /home/raj/jdk1.8.0_74/bin/javac: No such file or directory raj@raj-VirtualBox:~/jdk1.8.0_74/bin$ pwd /home/raj/jdk1.8.0_74/bin raj@raj-VirtualBox:~/jdk1.8.0_74/bin$ cp java java2 raj@raj-VirtualBox:~/jdk1.8.0_74/bin$ ./java2 bash: ./java2: No such file or directory raj@raj-VirtualBox:~/jdk1.8.0_74/bin$ java2 bash: /home/raj/jdk1.8.0_74/bin/java2: No such file or directory


Syntax highlight and MathJax is not rendered after reloading an edited post

I don't know how long this has been happening, but I recently noticed what seems to be a regression: after clicking the "An edit has been made to this post" banner that appears when a question or an answer has been edited while you're viewing it, any code syntax highlighting or math formatting in the post fails to render.  Steps to reproduce:   Open a question with highlighted code or MathJax markup that is likely to get edited soon. (The  or  is a good place to find some.) Leave the question open until someone edits it and the "An edit has been made to this post" banner appears. (For efficiency, open several questions in separate tabs and wait a few minutes until one of them gets edited.) Click the banner. Observe that the question gets reloaded, but it loses any syntax highlighting or math formatting.   (The bug also occurs for edited answers, but those tend to be harder to find on demand.  Unfortunately, editing a post yourself while having it open in another tab doesn't seem to work, since the banner never appears in that case.)    FWIW, the cause of this bug appears to be a missing call to styleCode() (or equivalent code) in the reloadPosts function in realtime-se.js, as included in the  bundle. (In particular, running styleCode() from the browser JavaScript console after reloading the post restores the missing syntax highlighting.)  I'm pretty sure this used to work automatically, so I suspect this is a regression caused by some recent code reorganization.


Is there any way to redownload games attached to another NNID?

I bought a used 3DS XL off Craigslist and the person had 3 digital copy games on the system when he sold it to me. He said I should be able to redownload at least 2 of them that he was pretty sure of when I reset it and set up my own account on it.    However, since doing the system reset and getting a NNID set up for myself they are not listed in redownload-able software. I contacted Nintendo support via chat line and they said that there was noting that can be done because the games still belong to the previous owner still.  Is there ANY way to get around this?  I have contacted the person I bought it from & they said they would try to find their NNID stuff and I just haven't heard from them yet. They were both great games & really want them back since they were included in the total price I paid for the system & all its stuff that came with.


SubjectID       StudentName ----------      ------------- 1               Mary 1               John 1               Sam   SubjectID       StudentName ----------      ------------- 1               Mary, John, Sam   Hi, i'm using SQL Server 2014. I would like to know if it's possible to use the STUFF() function to insert the result into one column. The examples i see online are all retrieving. I tried to do it based on the documentation by it doesn't seems to be correct.   Query   @"INSERT INTO ApplicationOtherInfo                          (ApplicationId, AppOptionCode                          ) values                          (@applicationId, @appCode                          )";  SELECT STUFF((SELECT ',' + AppOptionCode               FROM ApplicationOtherInfo                ORDER BY AppOptionCode               FOR XML PATH('')), 1, 1, '')


How to make special new folder in right click?

I want to create folder but it's name date of current day. I know how to make it in terminal by this command:  mkdir $(date -I)   How to add this to right click to be easy?


I want to change my link from usercp.php?do=our_pics&p=$i to usercp/our_pics/1.  I have this .htaccess code  RewriteEngine On RewriteRule usercp/(.*)/(.*) usercp.php?do=$1&p=$2   The problem is when I using the pagination to change the page to another, it doing redirect to main page or page 1, and that because there are problem in mod_rewrite code .  "Edit 1"    After enable RewriteLog and RewriteLogLevel 2, the following is the content of rewrite.log file When the problem occurs.  127.0.0.1 - - [06/Jan/2013:20:37:26 +0200] [localhost/sid#6828d0][rid#ec2180/initial] (2) [perdir C:/Program Files/wamp/www/ebdaa_v3/] rewrite 'usercp/our_pics/3' -> 'usercp.php?do=our_pics/3'  127.0.0.1 - - [06/Jan/2013:20:37:26 +0200] [localhost/sid#6828d0][rid#ec2180/initial] (2) [perdir C:/Program Files/wamp/www/ebdaa_v3/] strip document_root prefix: C:/Program Files/wamp/www/ebdaa_v3/usercp.php -> /ebdaa_v3/usercp.php  127.0.0.1 - - [06/Jan/2013:20:37:26 +0200] [localhost/sid#6828d0][rid#ec2180/initial] (1) [perdir C:/Program Files/wamp/www/ebdaa_v3/] internal redirect with /ebdaa_v3/usercp.php [INTERNAL REDIRECT]  127.0.0.1 - - [06/Jan/2013:20:37:26 +0200] [localhost/sid#6828d0][rid#724160/initial/redir#1] (1) [perdir C:/Program Files/wamp/www/ebdaa_v3/] pass through C:/Program Files/wamp/www/ebdaa_v3/usercp.php  127.0.0.1 - - [06/Jan/2013:20:37:26 +0200] [localhost/sid#6828d0][rid#ec6190/initial] (2) [perdir C:/Program Files/wamp/www/ebdaa_v3/] rewrite 'usercp/mainpage' -> 'usercp.php?do=mainpage'  127.0.0.1 - - [06/Jan/2013:20:37:26 +0200] [localhost/sid#6828d0][rid#ec6190/initial] (2) [perdir C:/Program Files/wamp/www/ebdaa_v3/] strip document_root prefix: C:/Program Files/wamp/www/ebdaa_v3/usercp.php -> /ebdaa_v3/usercp.php  127.0.0.1 - - [06/Jan/2013:20:37:26 +0200] [localhost/sid#6828d0][rid#ec6190/initial] (1) [perdir C:/Program Files/wamp/www/ebdaa_v3/] internal redirect with /ebdaa_v3/usercp.php [INTERNAL REDIRECT]  127.0.0.1 - - [06/Jan/2013:20:37:26 +0200] [localhost/sid#6828d0][rid#727158/initial/redir#1] (1) [perdir C:/Program Files/wamp/www/ebdaa_v3/] pass through C:/Program Files/wamp/www/ebdaa_v3/usercp.php


transfer files to local from remote machine A via remote machine B

I must transfer several huge files from a remote machine A to my local computer. The problem is that I can not access A directly, but instead I must access via another remote machine B. Unfortunately, machine B has a very limited amount of space, so I can not copy the files from A to B and then from B to local. Instead, I would need to use B as a kind of proxy. I was thinking in something as simple as possible that does not need to install or configure anything, hopefully simply using sftp, scp o ssh. Does anyone know how to do that?


I am studying linear regression lately and I notice this adjusted r-squared formula in a youtube video: $$adj. R^2 = \frac{\frac{SSE}{n-k}}{\frac{SSTO}{n-1}}$$ While the formula that I know is this: $$adj. R^2 = \frac{\frac{SSE}{n-k-1}}{\frac{SSTO}{n-1}}$$ I was about to comment in the yt vid that something is wrong but some people agree with it.  How come that both formula seems to be applicable? Why does the other one has a n-k degrees of freedom while the other has $n-k-1$?  I'm so confused. I don't think of a way that you can equate the other formula to another formula.


"A newer Command Line Tools release is available" but no updates in System Preferences or AppStore

When I upgrade a package, homebrew prompts this:  ==> Upgrading mysql@5.7 Warning: A newer Command Line Tools release is available. Update them from Software Update in System Preferences or https://developer.apple.com/download/more/.   I have XCode Version 11.3 (11C29) installed, and no updates in System Preferences or App Store      Opening Xcode does not prompt me to install command line tools either, how can I get the latest version?


How to prevent Exchange server from rebooting?

Every now and then our Exchange 2013 server (running on Windows 2008R2) will reboot during office hours, typically in the early afternoon (say, somewhere between 15:00 and 16:00) - apparently because the server thinks it wouldn't hurt anybody because nobody is really logged in. The reboots are always related to the server installing new upgrades automatically and users are annoyed because their Outlook makes problems (if they are lucky, it simply reconnects after a few minutes, but if they were in the middle of composing a longer mail the only way to save their work is by copy-pasting all to an empty Word doc, say, and restart Outlook).  The update settings are as follows:   install automatically (recommended) install daily at 06:00   So even if an update process should somehow take a whole hour, the reboot that might be necessary should happen at 07:00 in the morning and not nine to ten hours later, shouldn't it?  I would like to keep the update process as admin-friendly as possible, i.e., without the need to manually install updates off-hours or to manually schedule a reboot.  Q1: Why can it happen that the automatic reboot (always?) happens so many hours after the scheduled update installation time?  Q2: Is there any way to gobally prevent automatic reboots during office hours, i.e., to automatically delay an auto-reboot scheduled for between 08:00 and 18:00 to happen at 23:00 instead?


Making contextual filter conditions "OR" vs. "AND" in Drupal7

I have a view that needs to allow for the "OR" of a set of contextual filters (filtering on node references) rather than what appears to be the default of "AND". In the answer to a previous question here, someone suggested that there was a way to do this by changing the first filter group from OR to AND. My problem is that I am unable to find the menu to make this change.


Should I put job talks on my vita for positions I didn't get?

I have been on the social science academic market for a couple years, and I have been invited to interview and put together presentations ("job talks). I thought in both cases, the presentations were interesting and thought provoking and I wonder if i should include them in my vita.I have an "invited lecture" section already, so my thought is just to add them, but is that unorthodox? I would love to hear your thoughts on this.


When I try to access my hard disk on Windows I got the following error:  Error mounting /dev/sda2 at /media/debo/2290657790655279: Command-line `mount -t "ntfs" -o "uhelper=udisks2,nodev,nosuid,uid=1000,gid=1000,dmask=0077,fmask=0177"  "/dev/sda2" "/media/debo/2290657790655279"' exited with non-zero exit status 14: Windows is hibernated, refused to mount. Failed to mount '/dev/sda2': Operation not permitted The NTFS partition is in an unsafe state. Please resume and shutdown Windows fully (no hibernation or fast restarting), or mount the volume read-only with the 'ro' mount option.   Please can anyone help me on this?


I am searching google for answers but i could not get one module to convert doc/pdf/docx/rtf to text  Is there any python module to convert doc/pdf/docx/rtf formats to text?


How much brown sugar should I substitute for white sugar?

I'm making a cranberry sauce from fresh cranberries and want to substitute brown sugar for the 1 cup of white sugar without making the sauce sweeter.  What quantity of brown sugar do you suggest?


Output of a python script running as unit is out of order while shells seems unnafected

How would I get all outputs of systemd managed python2 script instantly into journal, just like it appears in terminal  I'm on centos 7, but seems to be same on arch  according to systemd manual, stdout and stderr should automatically go to journal  systemd config  #DefaultStandardOutput=journal #DefaultStandardError=inherit   Here is my unit /usr/lib/systemd/system/tick.service  [Unit] Description=Tick  [Service] Type=simple ExecStart=/home/stack/tick   script  #!/usr/bin/python import time import sys  print "Tick" sys.stderr.write('First error\n') time.sleep(10) sys.stdout.write("Tick\n") sys.stderr.write('Second error\n') time.sleep(10)   and here is the output from journal, notice the time and order  Oct 30 14:30:41 controller systemd[1]: Starting Tick... Oct 30 14:30:41 controller systemd[1]: Started Tick. Oct 30 14:30:41 controller tick[5020]: First error Oct 30 14:30:51 controller tick[5020]: Second error Oct 30 14:31:01 controller tick[5020]: Tick Oct 30 14:31:01 controller tick[5020]: Tick   With python3 even stderr is delayed until process ends  I tried similar c program, and seems to be same  but this does not seem to affect bash script  #!/bin/bash echo "Tick" echo "First error" 1>&2 sleep 10 echo "Tick" echo "Second error" 1>&2 sleep 10   journal  Oct 30 14:41:36 controller systemd[1]: Starting Tick... Oct 30 14:41:36 controller systemd[1]: Started Tick. Oct 30 14:41:36 controller tick[5084]: Tick Oct 30 14:41:36 controller tick[5084]: First error Oct 30 14:41:46 controller tick[5084]: Tick Oct 30 14:41:46 controller tick[5084]: Second error


On Android's root (/), what is the purpose of each folder? I want to learn the folder hierarchy structure. I would like to know the differences between Android 2.3 and 4.x, if they have different folders in "/".


I have Debian. I want to run Windows on the same hard drive, but in separate partitions. I don't want to start my computer "DualBoot" (DualBoot is causing problems for the computer). what should I do? Can I press a button (choose Windows partition) at boot and enter Windows?


View number of 'Up' and 'Down' Votes of a question/answer - Android App

This feature is missing in Android App and this  is same but in general (Mobile web).  Additionally, once this feature is implemented, we might accidentally hit the 'Up' or 'Down' vote (In smaller devices). The author might wonder why their post got downvoted.


I have a 2014 MacBook Pro experiencing . Catalina does not allow kexts to be deleted via this method. Unless I am able to delete or disable this kext my laptop will shut down randomly. Anyone know how to remove kexts in Catalina?


I found some questions and answers where one of the relevant words  contains a typo. (In my case the user wrote 'QlickView' instead of 'Qlikview'.)   I would like to change (edit) these questions and answers, so that the search finds them. But it is not possible to save one letter changes.   Should I flag these questions and answers or is there a better way to improve?


I'm new to Stack Exchange.  I've noticed time and time again, questions get little "clarification requests" in a shaded blue directly beneath. These comments are clearly not posted answers, but I don't see how to post them myself. My options are "answer" or "suggest edit" (I'm on the mobile app). The first posts an answer, the latter asks for me to change the question's content.  Are those comments edit suggestions? Do I need to visit the full website?


Question edit made answer off-topic - what to do with that answer?

Let's say there is a question. It was ambiguous. Only for one user it wasn't and he answered. And then question got clarified. It cannot even count as drastic edit. It left answer looking off-topic, low quality. So it's either upvoted by people who knows how the question looked earlier (bad for future readers), or downvoted by ones looking at "now" (bad for honest user who answered). Is there any way to deal with these situations?


I'm pretty sure the sentence "I'm quite an ambitious man" is standard English, but I wonder if the adverb 'too' can be used the same way. To put it another way, I'd like to know which of the following sentences are correct:  (1) I'm a too ambitious man  (2) I'm too ambitious a man  (3) I'm too an ambitious man (where too means very, not also)  Thanks in advance for any contributions


Table cells larger than they are meant to be

I've created a map system for a game that runs on the principle of drawing the picture of the map from tiles. There are many reasons for this which I won't go into here but if you really want to know then I'm sure you can find out how to contact me ;)  I have  so you can see exactly where the problem lies and the source. The issue is the line between the top 2 tiles and the bottom 2 tiles, I can't figure out why it's gone like this and any help would be appreciated.  In the source is a marker called "stackoverflow", if you search for "stackoverflow" when viewing source then it should take you to the table in question.  I have also uploaded an .


I have heard often that you should replace a worn chain, that a chain lasts somewhere between 800-1200 miles, and that if you don't replace the chain on time, you'll need to replace the cassette when you get a new chain.  My question is this: instead of going through 4 or 5 chains between cassette replacement, what is the downside of riding the same chain until the cog needs replacement? And, if you do that, how long would you be able to do so?


Why are flip-flops (bistable memory devices) called flip-flops?   says that the terms "trigger circuits" and "multivibrators" were used in the past but not the justification for the term "flip-flop".


Why isn't all of physics based on other rates of change

Define the  to be   $$J(f)={{d^3 f} \over {dt^3}}$$  Why don't we use the concept of jolt more often considering that the change in acceleration is most definitely an important characteristic in the universe. Is there some mathematical proof that essentially kicks jolt out of the useful units club? However, it seems like initial conditions relying on jerk/jolt should be the norm rather than the exception. I mean, the universe doesn't care about what's easy to measure...  In addition, what about the other neglected members of the rate of change community. Why isn't   $${{d^4 f} \over {dt^4}}$$  or  $${{d^{55} f} \over {dt^{55}}}$$  Used in physics? In fact wouldn't having a function that just gives all order derivatives of a function useful? You could presumably study the rate of change of the spread rates of change!  $$S(f(x),n)={{d^nx} \over {dt^n}}$$  In fact, on a more math intensive note, using fractional calculus, you could treat this Spread function as a real continuous function, since fractional calculus defines fractional order derivatives.  Of course, lets not leave out the integral. Shouldn't an expression that integrates the position with respect to time have physical meaning?  $$\int x \ dt$$  what about $$\iint x \ dt$$ or even $$\iiint x \ dt$$  In fact, it seems you could derive a function very similar to the one mentioned above.  Questions: So why don't we use these other forms of rate of change? In addition, isn't the integral of position important. I mean, it has units of $L \cdot M$ which seems to me at least to be very important. In addition, what about this Spread function, what physical significance does it have. In addition aren't initial conditions subject to the effects of jerk/jolt etc...!!


Motion tracking footage from 24 DSLR cameras fails, but why?

I am driving a bullet time rig with 24 cameras and now I want to put 3D objects into the scenery. The 24 frames were shot in a studio with a clean white cove where markers were put all over the walls, to make tracking easy. Now I manually added the tracking points to the footage but blender fails to solve the camera. I suppose with such markers it should be possible. However a lot of the markers cannot be solved. Now since the footage is made with a bullet time rig, a lot of the markers aren't visible in all frames. I'd really appreciate, if someone could give me a hint how to resolve the camera and which settings would be best when taking the shot.  Thank you so much!


New questions feed looks great, except the reputation identifier needs a space

Consider this:    We need a space there! Yikes. At first I thought the user's full handle was developingo31. Maybe if it was a different color too that might be neat? Like a slightly lighter (or darker) gray than the "asked xxx ago"?


It seems most of the questions tagged  on Stack Overflow are just intended to indicate "there's something wrong with my program", which would cover probably at least 80% of all questions on Stack Overflow.  There are some questions where it seems to refer to a possible bug in a framework or utility. I'm not sure the tag is really all that useful in that case either.  What does meta think?


Excel: Expand list to include duplicates

I am trying to dynamically expand a list to include duplicates. I managed to achieve this without VBA, but after condensing several columns containing intermediary functions I have tied myself in a knot of circular references. I'm not convinced I can get it working again, so I turn to SU for help.  I have a table as below:          APPLE  BANANA   CHERRY  DATES JOHN      x                x PAUL              x GEORGE    x       x RINGO     x       x        x      x   I need to create from this two columns containing the following:  JOHN         APPLE JOHN         CHERRY PAUL         BANANA GEORGE       APPLE GEORGE       BANANA RINGO        APPLE RINGO        BANANA RINGO        CHERRY RINGO        DATES   That is, each individual instance of Fruit is listed. I am able to create the second column, i.e. the list of fruits according to the Eater; I just can't get the first column.  From here the list will be expanded again. Let's say I have another table:  FRUIT    LINES APPLE      2 BANANA     3 CHERRY     1 DATES      2   The ultimate list I would like to end up with is:  JOHN         APPLE          1 JOHN         APPLE          2 JOHN         CHERRY         1 PAUL         BANANA         1 PAUL         BANANA         2 PAUL         BANANA         3 GEORGE       APPLE          1 GEORGE       APPLE          2 GEORGE       BANANA         1 GEORGE       BANANA         2 GEORGE       BANANA         3 RINGO        APPLE          1 RINGO        APPLE          2 RINGO        BANANA         1 RINGO        BANANA         2 RINGO        BANANA         3 RINGO        CHERRY         1 RINGO        DATES          1 RINGO        DATES          2   That is, each line is repeated according to the number in the "Fruit/Lines" table. I'm sure this second step is just a replication of the first step, rather than one complete set of functions.  Any help will be appreciated.  The duplicate question, , doesn't cover the dynamic element; steps 5 and 6 are "copy list and paste values" and "filter column and delete nulls" are not suitable for this application.


What's going on here?  It was previously occupied, but they all moved out and now they wont go back. I haven't touched it.    I'm on PC latest update. I tried replacing the table and chair and the blocks! If anyone else has this problem please tell me how you fixed it or if its something to do you the biome.


Is my pork Safe to eat after 3 hours sitting out??

So I put some pulled pork in the crock pot on low for about 5 hours when my boyfriend turned it off without me knowing.. Recipie said 7 hours total on low. So after about 3 hours of it being off we turned it on warm and left it on overnight.. In the morning I turned it back up to low and it cooked for about another 5 hours (I was told you can't really overcook pulled pork, just gets more tender) and I am wondering if it is safe to eat??


Should the question mark be in the middle of a sentence?

The goal is to answer questions of the form "is vertex v connected to w?" in constant time.   Should the question mark be there?  A related question is how this sentence might be made better?


Besides $ω_{(1)}$ what space has Stone-Cech compactification and one-point compactification the same?

For the ordinal space $ω_{(1)}$, the Stone-Cech compactification and the one-point compactification coincide. What is another such space?


OS X Keychain keeps prompting me for my SSH passphrase even though I save it (OS X 10.6.8)

Every time I log in to a remote server with SSH, OS X keychain prompts me to remember the SSH passphrase. I type in the passphrase and check the box to remember it. I then connect ok to the server but then the next time I get prompted again and so on...  I have a private key to ssh into my server and the connection works. In my hosts file I have:  Host myhost     HostName xxx.xxx.xxx.xx     GlobalKnownHostsFile ~/.ssh/known_hosts     port 22     User myuser     IdentityFile ~/.ssh/mykey_dsa     IdentitiesOnly yes   .. and then I type ssh myhost  This is only a recent problem so I suspect and issue with Keychain? To be clear, I can 're-add' to keychain every time and connect but this defats the purpose. The permissions on my dsa key are set at 600 or -rw-------@  I tried repairing disk permissions but that did no good. My Google-foo is also failing me, nothing of use came up. So I am not sure if this an OS X / keychain issue or an SSH issue.   update: When I try ssh -vvv myhost, I think it reveals the issue:  debug1: Trying private key: /Users/danny/.ssh/mykey_dsa debug1: PEM_read_PrivateKey failed debug1: read PEM private key done: type <unknown> debug3: Not a RSA1 key file /Users/danny/.ssh/mykey_dsa. debug1: read PEM private key done: type DSA Identity added: /Users/danny/.ssh/mykey_dsa (/Users/danny/.ssh/mykey_dsa) debug1: read PEM private key done: type DSA debug3: sign_and_send_pubkey debug2: we sent a publickey packet, wait for reply debug1: Authentication succeeded (publickey).   ... and after that I get connected. I think this crux of the matter is:  PEM_read_PrivateKey failed   Update 2: After trying the same key and settings on another Mac with 10.6.8 as well, everything worked fine so I think this is a Mac specific question, possibly a permissions keychain issue.   Update 3 I also tried a clean install of Mountain Lion (10.8.1) and alas the same issue which I totally don't get.   Possibly related:   Update 4


$f : S^1 \rightarrow  \mathbb{R}$ is a continuous map. Define $$A = \{(x, y) \in S^1 \times S^1: x \neq y, f(x) = f(y)\}.$$   We want to prove that $A$ has uncountably many points.    It seems very evident, but I want a rigorous argument. Thanks in advance.


QGIS: Join by Location: Option to retain all attributes of spatially related objects of my join layer

I am facing the problem that I want to join the attributes from one specific column of ALL intersecting features from my join layer to my target layer in case of an intersection (1:n relationship) using QGIS. I can´t find any option to do so having wasted all week on this problem. I am looking for a strategy, concatenating the desired attributes of my join layer in a column of my target layer.  Do you know if there is any way to do so without having to do too much scripting?


Can I have two similarly-named legendary creatures on the field?

If I have two different Ulamogs, can they both be on the field? They both share Ulamog as part of their name, but their entire names are different.     One is , while the other is . Does legend rule carry across instances like this, or would it only apply if I had two of either of them on the field?


Need help understanding simple FM transmitter

I made a simple FM transmitter following  and it worked! Now I need some help to understand how.  My coil is made of 1 mm copper wire has 6 turns and 8 mm wire diameter. According to this online calculator:  this means that: L = 3.9e-7 H  I did not have any 5 pF trim capacitor so I used a 3 pF capacitor instead.  Am I correct in assuming that the frequency this will transmit on can be found by looking at the L1 C2 as a LC oscillator and using the frequency formulae:  fR = 1/(2*pi*sqrt(LC))  ?  If so I should get fR = 147 MHz. Which is strange since I received the signal on 91.5 MHz on my radio.  In a LC circuit I understand that the signal decays exponentially over time. That is hopefully not happening here. Why? Because of C4 maybe?  Also what is the purpose of C1?  If I want to increase the range of this FM transmitter somewhat can I do this by simply replacing R2 with a 470 Ohm resistor?  Are there free simulator programs that let me see the resulting spectrum at the antenna?


Spring Config server: Truststore not found Resource location must not be null

I'm getting this exception:  java.lang.IllegalArgumentException: Resource location must not be null     at org.springframework.util.Assert.notNull (Assert.java:193)     at org.springframework.util.ResourceUtils.getURL (ResourceUtils.java:130)     at org.springframework.boot.web.embedded.tomcat.SslConnectorCustomizer.configureSslKeyStore (SslConnectorCustomizer.java:133)     at org.springframework.boot.web.embedded.tomcat.SslConnectorCustomizer.configureSsl (SslConnectorCustomizer.java:92)     at org.springframework.boot.web.embedded.tomcat.SslConnectorCustomizer.customize (SslConnectorCustomizer.java:58)     at org.springframework.boot.web.embedded.tomcat.TomcatServletWebServerFactory.customizeSsl (TomcatServletWebServerFactory.java:317)     at org.springframework.boot.web.embedded.tomcat.TomcatServletWebServerFactory.customizeConnector (TomcatServletWebServerFactory.java:300)     at org.springframework.boot.web.embedded.tomcat.TomcatServletWebServerFactory.getWebServer (TomcatServletWebServerFactory.java:166)     at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.createWebServer (ServletWebServerApplicationContext.java:179)     at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.onRefresh (ServletWebServerApplicationContext.java:152)     at org.springframework.context.support.AbstractApplicationContext.refresh (AbstractApplicationContext.java:544)     at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh (ServletWebServerApplicationContext.java:140)     at org.springframework.boot.SpringApplication.refresh (SpringApplication.java:759)     at org.springframework.boot.SpringApplication.refreshContext (SpringApplication.java:395)     at org.springframework.boot.SpringApplication.run (SpringApplication.java:327)     at org.springframework.boot.SpringApplication.run (SpringApplication.java:1255)     at org.springframework.boot.SpringApplication.run (SpringApplication.java:1243)     at com.tsystems.iberia.tdev.wsecsccs.WsecSccsApplication.main (WsecSccsApplication.java:12)     at jdk.internal.reflect.NativeMethodAccessorImpl.invoke0 (Native Method)     at jdk.internal.reflect.NativeMethodAccessorImpl.invoke (NativeMethodAccessorImpl.java:62)     ....   As you can see is telling me that:Resource location must not be null  My spring configuration related issue is:  server.ssl.trust-store: file:keystore.jks server.ssl.trust-store-password: secret   Obviously, keystore.jks exist and contains certificate. This is how I've built the ketstore:  $ keytool -importcert -trustcacerts -file ra-sec.pem -alias vault.ra-sec.svc -keystore keystore.jks   Any ideas?


I am trying to create a method that allows for a variable number of inputs. I was trying to implement  answer (see the code below) however, I got an error when I tried to run my code.  Code  header:  template<typename T, typename... Args> void vSend ( T tIn, Args... AArgs ); template <typename T> void vSend ( T tIn );   CPP  template<typename T, typename... Args> void Connector::vSend ( T tIn, Args... AArgs ) {     pPacketToSend << tIn;      vSend(AArgs...); }  template <typename T> void Connector::vSend ( T tIn ) {     pPacketToSend << tIn;      tSocket.send(pPacketToSend); }   Error  Undefined symbols for architecture x86_64:   "void Connector::vSend<int, int>(int, int)", referenced from:       Updater::Update(sf::Image*) in updatedirector.o ld: symbol(s) not found for architecture x86_64 clang: error: linker command failed with exit code 1 (use -v to see invocation)   Edit (Answer)  Turns out templates may only be implemented in the header file.


Reference for $\text{Var}(X)\le (b-a)^2/4$

I am not a statistician, but am working a proof for the upper bound of an expression which contains the variance of a variable which obtains its values from a closed interval, [0,1]. I have seen in several places (mostly forums and web pages) the result that $\text{Var}(X)\le \frac{(b-a)^2}{4}$ for $a\le X\le b$. I would like to use, and cite, this result but am having an unusually difficult time finding a solid reference. Could someone here recommend one for me?


Shell script options with parsing arguments

I have the shell script  CONTROLLER_IP="" if [ "$#" -eq 1 ] then     CONTROLLER_IP=$1 else     echo "Usage : create_endpoint.sh --controller-ip <Controller IP>"     exit 1 fi   but its executing like this ./create_endpoint.sh 10.10.10.1   I want to execute like this /create_endpoint.sh --controller-ip 10.10.10.1


I'm sure this question must have been answered before...  What's the difference between Modal window and a Popup? What to use when? Is there a good article I can read?  Thanks, Roland


I want to have two page.tpl.php on my site ..one for my front page and other for rest of pages ...now both have same name page.tpl.php what should I do to make one of them for Front page and other for rest of pages


I have an Excel spreadsheet that has this formula:  =IF(ISBLANK(B6),"",SUM(Sheet1:Sheet10!O6)+Sheet11!P6+Sheet12!T6)   I would like to use this spreadsheet in Google Sheets so I can get it on other devices and collaborate, etc.  When I imported the Excel sheet to a Google Sheet it changed the formula to:  =IF(ISBLANK(B6),"",SUM(Sheet1!O6)+Sheet11!P6+Sheet12!T6)   It removed the range of referenced sheets in the first set of brackets after the SUM.  Does anyone know if Google Sheets can do this?


Why didn't Harry's touch hurt Voldemort in "HP and the Deathly Hallows"?

I watched some of the Harry Potter movies today, and there is something I didn't understand.  In the first movie, Harry's touch hurts Professor Quirrell, but when Voldemort and Harry "fall-fly" during the last scene, the touch doesn't seem to affect him. Is there a canon reason as to why?


Experimental data for asymmetric Newton cradle

Using a "successive impact model" (as if each ball were seperated from the other ones), I produced the following animations:    You can see any combination of balls with masses of 1 or 2 (left) or 1 and 4 (right).  Unfortunately, I do not have any Newton cradle to make some experiments, and I'd like to compare my results with observations. I contacted the author of , which is the most instructive one I found about asymmetric Newton cradle. In particular, he writes that the "OoO" configuration behaves as the "ooo" one, which is not what I simulate. But the author is not sure whether who is wrong because he did the experiments a long time ago.  I am especially interested in asymmetric Newton cradle with simultaneous impacts: left and right balls collinding at the same time.   Please let me know if you have any idea on where to find such experimental data.  Edit Just of few general remarks to avoid extending the comments.    Energy and momentum are conserved. However, they are sufficient to ensure uniqueness of the post-impact velocities only when there are 2 balls. The successive impact model precisely consists in propagating the impact ball after ball, and therefore leads to a unique solution (which conserves momentum and energy globally). From the waves point of view, changing the mass of a ball can be done by increasing the diameter, or the density (or a combination of both). This simple model cannot account for such subtleties of course, but maybe it does not matter when the balls are "small enough". Even if I think it's quite basic, following WetSavannaAnimalakaRodVance's comment, I am ready to hand out my Mathematica code to anybody who wants it. I'll check for good ways to share it.


Are there any reputable studies on spanking?

Is there any scientific evidence that non-harmful spanking does or does not exist? Furthermore, is it ever effective (whether or not it is harmful)?


Suitability of topology book for self-study

Good day,  I have an engineering background and I recently took an interest in topology. I found this book Topology (2015) by Marco Manetti (ISBN 978-3-319-16958-3) and starting going through it.   Unfortunately I am experiencing a lot of difficulties with his definitions in the introductory chapter, which correspondingly means I can't quite do the exercises contained therein. Although I do understand the set-theoretic notation he uses, I find it difficult to understand the significance of these definitions and to develop a kind of intuition for them. Hence the question: is this book suitable for a beginner in this subject?  Best wishes


Why can't an electric field line suddenly break?

My book has the following question in it as an exercise:  An electrostatic field line is a continuous curve i.e. a field line cannot have sudden breaks. Why not?  I cannot seem to be able to reason for or against this statement.  Can somebody please tell me why they can't suddenly break and if that were to happen then what will be its outcome?


What is the rationale behind safely removing USB media from windows PCs?

Quite often when I'm in a rush, I automatically pull out a USB pendrive or USB cable from an external hard drive from my desktop PC or laptop, without right-clicking on the safely remove icon in the system tray and unplugging via this route. So far nothing untoward has happened every time I have "been in a rush".  What is the rationale behind right clicking on the safely remove icon and can I really lose information on USB media if this is not carried out?  Edit  Is the vunerability of losing such information greatly increased, if the usb media is still flashing at the time of pulling it out of the computer (as opposed to non-flashing)?


Prove a cancellation law for multiplication of numbers that is for 2 natural numbers b and c that if some natural number a we knew ab = ac prove b =c

The question also states that we dont have division and we have not proven any cancellation law, nor do we have 0.  I thought of proving this by induction:  Base Case: $n=1$.  $b$ x $1$ = $c$ x $1$ implies $ b = c$  I am stuck on how to do the induction part?


How to calculate days between two dates in JavaScript

How to calculate days between two dates by using JavaScript?        How to get only 'day' from the date.   How to get only 'month' from the date.   How to get only 'Year' from the date.   How to calculate 'year' from the 'days'      This type of questions are have Answer is below refer it


Why is the work done by someone pushing a cart not zero?

We know that when force is perpendicular to displacement, then the work done by it is zero. If this is true, then why do the vegetable vendor (who pushes the cart by applying perpendicular force) feels tired?


Is it possible to add a Stack Overflow user as a fav?


When the update with the pets came out I received a free pet. Since then I have opened a fair few lunchboxes with none entailing a pet. Is the only way to get more pets to buy them?


Why does Client Height value doesn't apply to other elements?

I want my sidebar to have spacing from top equal to header's height. When I use clientHeightin js, although it returns the right value when I print it via alert(), it doesn't apply to other elements as marginTop or top value. (Position was included while using top). HTML <body onload="sidenav_height()">  ... </body>  JS function sidenav_height(){   var height = document.getElementById("header").clientHeight;   document.getElementById("sidenav").style.marginTop = height; }


A variation on the induced topology (subspace topology)

One of the easiest ways to find a topology on a set is to used the Induced Topology. Induced Topology: Suppose you have a set $X$ and a topology on $X$ called $\mathcal{T}_X$. Suppose $Y \subseteq X.$ Then we can find a topology for $Y$ (call it $\mathcal{T}_Y$) as given by: $\mathcal{T}_Y=\{O \cap Y  \mid O \in \mathcal{T}_X\}$. My question is: does the induced topology still hold for sets $Y \not \subseteq X.$ Suppose $Y \cap X = \emptyset.$ Can we still inherit a topology on $Y$ if $X$ and $Y$ are disjoint? I'm going to say no. Here's my test: Let $X =\{1,2\}$ and $\mathcal{T}_X = \{\emptyset,\{1\},\{1,2\}\}$ Let $Y = \{5\}$ Then, following from our induced topology method, $\mathcal{T}_Y=\{\{5\} \cap \emptyset, \{5\} \cap \{1\}, \{5\} \cap \{1,2\}\} = \{\emptyset,\emptyset,\emptyset\}$ But this fails to satisfy definition of topology since $Y=\{5\}$ and $Y \not \in \mathcal{T}_Y.$ So it would seem that we need $Y \subseteq X$ so that $Y \in \mathcal{T}_Y$, otherwise we end up with a bunch of empty sets. Is my reasoning here correct?


When a photon escapes a black hole, why is it red shifted?

I think that is how astronomers hunt for these elusive objects using radio telescope and also gravitational lensing, I'm wondering how these photons lose their energy while encountering black hole or some massive objects and I remember energy cannot be created or destroy so what gives?


Continuous function with compact domain has continuous inverse

Let $A,B\subset\mathbb R$ and $f:A\to B$ be an invertible function (so 1-1 and onto). Prove that if $A$ is compact and $f$ is continuous, then the inverse $f^{-1}:B\to A$ is continuous. And give a counterexample when $A$ is not compact (no transcendentals).  If $f$ is continuous, then for every sequence $\{x_n\}$ in $A$ that converges to $L$, $\lim_{n\to\infty}f(x_n)=f(L)$. We need to prove that for every sequence $\{y_n\}$ in $B$ that converges to $K$, $\lim_{n\to\infty}f^{-1}(y_n)=f^{-1}(K)$ (Is this sufficient to prove that $f^{-1}$ is continuous?), I'm not sure how to proceed from there, and I'm having trouble coming up with a counterexample as well.


if $M$ is the midpoint of $BC$ then find the measure of $AMC$.    I tried to use the angles to find $AMC$ but I don't know how to use that $M$ is the midpoint of $BC$.


how to display a list of all unique words that appear four or more times in the text?

So far, i have figured out how to get all the words to show, alongside the number which indicates how many times each unique word appears in the text. However, i cannot figure out how to get another list which displays all the unique words that ONLY occur 4 or more times. Any idea on how i can achieve this because i think i have done the hard bit here, but i would just like to know how i can get this next part.


Should "Yes, delete it" be red, or green?

Designing an interface for a CMS (Content Management System), I stumbled upon a paradox and I'm a bit confused about what to do and why to do it..  Context  Before deleting an album, the user is asked to confirm the action.  Green "Yes"    Red "Yes"    Which option is more intuitive for the user?


Determine if the sequence $a_{n+1}=\arctan{a_n}$ is convergent and compute its limit.

Determine if the sequence $\{a\}_{n=1}^{\infty}$ defined by $$a_1>0\\a_{n+1} =\arctan{a_n}$$ is convergent and compute its limit.  Will Banachs Fixed Point theorem be of any help here?  My attempt.  We note that the recurrence relation is of the form $x_{n+1}=f(x_n),$ let's introduce the help function $f(x)=\arctan{x}.$ I know that the equation $f(x)=0$ has a root $x=0$, so I'll choose an interval $I=[0,\frac{1}{2}].$ In order to use the fixed point theorem, the following criterias have to be met:   $f(x)$ has to be defined and continuous on $I$ (OK!) $f(x)\in I$ for each $x\in I.$ (OK!) There should exist a $0\leq k<1$ such that $|f'(x)|\leq k<1.$   If all of these are met, it follows that $a_n$ converges to the unambiguous root of the equation $x=f(x)$.   The third criteria is where I run into problems. I get that  $$|f'(x)|=\frac{1}{1+x^2}\leq1,$$  So my $k$ is $1$, but I need it to be less than one! How can I go around this problem?


How to control the orientation of an Arrayed Mesh Object following a Curve (NurbsPath)

I'm trying to make the stairs railing poles with an Array following a Curve. Is there a way to control which way the Poles are facing? I want to point them all straight down (vertically).


What is the first number for in a 4-number chmod argument (such as `chmod 4555`)?

When I install a program, it recommends me to do chmod 4555. Okay, i know about values if I just use three numbers. For example  chmod 555 test-file   will give  -r-xr-xr-x   4 for write, 2 for read and 1 for execute. But, when I do this:  chmod 4555 test-file   it gives me  -r-sr-xr-x   So, x changed to s. What's that mean?


Large snap packages because of dependencies

Snap packages each have their own copy of dependencies. This means there are lots of packages in each snap, which would equate to large package sizes. Wouldn't this mean that snaps would be so much bigger than traditional debs? How can I make them smaller? I have limited space.


How to force a Bash word to reference an alias, function, file, etc?

When trying to add a bit more detail to a related , I realized I don't know how to specify which one of the available Bash word types to execute. According to help type there are five word types:   alias keyword function builtin file   It's possible for a word to have several types (true is just an example; a more commonly overridden word would be cd):  $ type -a true true is a shell builtin true is /bin/true   How do you force the execution of a specific synonym? So far, in order of precedence:   alias: This is a special case since it has precedence over all the other synonyms. Forcing this would only be useful when the command should fail if the alias is not defined.  $   keyword:  $   function:  $   builtin:  $ builtin true  file:  $ command true $ $(which true) $ /bin/true    :   Quoting a word excludes aliases and keywords. That is,  $ 'true'   will run only the function, builtin or file.


Getting notified when a question is put on hold

Is it possible in some settings to get a notification when a question is put on hold?  I normally don't look very often on SE even if I have posted a question. My questions normally don't get any answers, and I simply forget about these questions.  Now some of them are put on hold, and I don't even know it. I don't look at my questions daily, because I get notifications when I get a comment or an answer.  I also heard that if you don't improve on-hold-questions your account will be deleted some day or you can't ask any questions any more.  I know that there is a similar question, but it seems to me that the discussion of eight answers was ended about five years ago, so I don't know if this is up-to-date. And it doesn't provide any answer to me either.


The condition to receive flight compensation via EC261 are:  the person has:   a confirmed reservation on the flight, and arrived in time for check-in as indicated on the ticket or communication from the airline, or, if no time is so indicated, no less than 45 minutes prior to the scheduled departure time of the flight OR have been transferred from the flight for which he/she held a reservation to some other flight   In addition, if the delay is more than 5 hours, the passenger has a right to forfeit the flight and receive the ticket price back.  Does it mean that if the airline notifies about a long delay and passenger cancels the ticket, he still has to arrive in time for check-in to receive cash compensation?


Is it possible to prove  $f: \mathbb{R} \to \mathbb{R}$ is continuous everywhere iff it is sequentially continuous everywhere  without the axiom of choice?


Can't open synaptic package manager via command line

When I try to open synaptic via the command line, I got this:  user@hostname ~ $ sudo synaptic [sudo] password for user:  No protocol specified  ** (synaptic:4516): WARNING **: Could not open X display No protocol specified error: XDG_RUNTIME_DIR not set in the environment.  (synaptic:4516): Gtk-WARNING **: cannot open display: :0   What should I do?


I've refreshed the page after some time on stackoverflow and all my reputation is reset. I saw a "-4600" notification and I was back to 100 or something (I was around 4600 before).  Also the username and real names were different (something like user984398). The only thing I remember doing was I changed my real name.  I can see all my answers though and still have my badges. And the log in here:  looks fine.  My profile:


Why do we need $\sup$ and $\inf$ when we have $\max$ and $\min$.

In my analysis text, it seems that $\max$ and $\min$ are replaced by $\sup$ and $\inf$ for 1D single variable function, why is this the case?


I've created a SQL table with UTF-8 encoding (by using engine=MyISAM charset=UTF8;"). Now, after inserting the following input : אבג, the database contains a record with &#1488;&#1489;&#1490;.  I'd like to know whether there's another encoding issue I need to take care of in order to get Hebrew text instead of signs and numbers.


Would passing horizontally polarized light through a varying width vertical slit allow you to measure the positional (x) amplitude of light?

I have found closely related questions on StackExchange, but (surprisingly) not this exact question.  Seems some answers say individual photons do not have amplitude, only when traveling with other photons, forming a wave.  But even then, can't the amplitude be measured?  If so, what are the range of amplitudes and how do they vary?  Based on the frequencies and energies of the light?  Does higher frequency correspond to lower amplitude?  Moderators: This question is not a duplicate to this question:   That prior question is more about the formula for calculating electromagnetic energy amplitude of a single photon. My question is about an experimental way to MEASURE the positional (x) amplitude of the wave passing through a specific apparatus.  Two very different things.  Thanks.  I have updated my question to a more specific thought experiment:  If you had a vertical slit with a horizontal width that could be varied, and you passed horizontally polarized light through this slit, wouldn't the slit block any photons from passing through it if the width of the slit was smaller than the amplitude of the light waves?  Wouldn't we at least get a predicted or average amplitude, even with uncertainty principle?  Wouldn't the energy/frequency/wavelength of the wave also have some correlation to the amplitude?


How to make this unbreakable - Minecraft 1.14.2 replaceitem Command

I have the   replaceitem entity @a container.0 crossbow{display:{Name:"\"Paintball Cannon\"",Lore:["\"Put the fireworks in your offhand, and watch them go BOOM!\""]},Enchantments:[{id:quick_charge,lvl:3}]}"    command set up, but I do not know where to put the {unbreakable:1} tag to make the item unbreakable


Question  if we have matrices $A$ and $B$ which are symmetric. Both of these satisfy: $$  A=A^T$$ Is $AB=BA$ true ?  Attempt to solve  Now if $A$ and $B$ are symmetric then $AB$ most be symmetric too.  $$ AB=(AB)^T=B^TA^T=BA $$  problem is how do you proof that if $A$ and $B$ are symmetric also $AB$ is symmetric ?  If somone could provide some insight on this that would ge highly appreciated.  Thanks,  Tuki


How do I prevent new villager trades from spawning?

When making a custom adventure map, usually you only want the trades you programmed into a villager to show up. By default, however, the game will try to spawn new trades when the last one is made. The classic way I'm seeing in tutorials to prevent new trades is to make the last trade untradeable; however, with the release of 1.7, a lot of the old item IDs that were unobtainable have been removed from the game altogether, and following the tutorial I have crashes the game when the trade interface is scrolled to the last trade.   So there's two parts to this question:   Is there a better way to prevent new trades with the 1.7 mechanics? Or with the snapshots of 1.8 mechanics? If not, what is a safe data ID to use to prevent the last trade from being a real trade as of 1.7?


Why not the one-time pad with pseudo-number generator

I am very new to cryptography (so be kind), but I have a question that may seem silly.   If the one-time pad is the perfect cipher and impossible to crack, why would the following algorithm not be one of the strongest:  To encrypt:   generate a random bit array using a pseudo number generator with the key as the seed  The generated bit array is the size of the data use a simple XOR to encrypt using the generated bit array   To decrypt:   pseudo-random number generator will generate the same bit array with the same seed (the key) generate bit array the same size of the encrypted data run XOR on encrypted data using bit array that's generated   This is very simplified, but you can imagine how for larger encryption you could break down the data into blocks, and in order to ensure that the block bit arrays are random a new seed for each can be derived from the key. So, if $f(k)$ is the pseudo random number generator, and b is the block number, you can encrypt each block with $f(k+b)$. ($k$ is key)   Instead of using a pseudo-random number generator, you could use some hash algorithm to generate the pad.    (assuming you can use equivalently strong keys) would this not be a very strong cipher method? Perhaps it may be strong and heavy on memory since the pad needs to be the size of the data. So during encryption and decryption you need to generate a pad that's equivalent to the size of the data.   Is there a flaw in this algorithm, or would something like this not be practical and much slower than current standards?


Proof that Thomae's function doesn't have a limit as $\lim_{x\rightarrow x_0}$, $x_0\in \mathbb{Q}$

I'm trying to proof that the Thomae's function doesn't have a limit as  $\lim_{x\rightarrow x_0}$, $x_0\in \mathbb{Q}$.  I'm pretty sure, that I can solve this by using the $\epsilon-\delta$-critereon, but I cant figure out how. If a limit would exist, that would mean:  $\forall\epsilon>0 \exists\delta : |f(x)-L|<\epsilon, \forall x\in D, 0<|x_i -x|<\delta$  I'm pretty sure that you simply can't find a matching $\delta$ as in the environment of each rational number there are some irrational numbers where the Thomae's function is equal to $1/q$ and not $0$.   Could you help me to complete this proof by helping me arguing&writing this mathematicly correct?  Edit:  This isn't a duplicate because I'm looking for the limit and not discontinuity. I have to proof this with the $\epsilon-\delta$-critereon for the limit and not for the discontinuity (even though they are kind of similar, they're different!)


Using one group separator for integer part and another for decimal part (siunitx) (modified)

I found this link  the code from jfbu is almost perfect, except I need grouping of three on each side of the decimal.  So This code      %% GROUPING BY FOUR GOING FROM THE LEFT TO THE RIGHT     %% 1234567-->{1234}{567}      \def\aegroupbyfourR #1{\romannumeral0\expandafter\aegroupbyfourR@a                     \romannumeral-`0#1\relax\relax\relax\relax\dummy }      % we first check here if "short", for technical reasons     \def\aegroupbyfourR@a #1#2#3#4{\ifx #4\relax         \expandafter\@firstoftwo         \else\expandafter\@secondoftwo         \fi         {\aegroupbyfourR@short #1#2#3#4}{\aegroupbyfourR@b {{#1#2#3#4}}}}      % space to feed the \romannumeral0. We need to check for emptiness     %       \def\aegroupbyfourR@short #1\relax #2\dummy {\if\relax #1\relax         \expandafter\@firstoftwo          \else\expandafter\@secondoftwo         \fi { }{{#1}}}      \def\aegroupbyfourR@b #1#2#3#4#5{\ifx #5\relax         \expandafter\@firstoftwo         \else\expandafter\@secondoftwo         \fi         {\aegroupbyfourR@c {#1}#2#3#4#5}{\aegroupbyfourR@b {#1{#2#3#4#5}}}}      \def\aegroupbyfourR@c #1#2\relax #3\dummy {\if\relax #2\relax         \expandafter\@firstoftwo          \else\expandafter\@secondoftwo         \fi % Notice that #1 is never empty in this branch         {#1}{#1{#2}}}   Needs to be modified to only three spaces.  $\aenum{+12504.312423593}$ -->   +12,504.312 423 593


Network Render for one image using tiles?

Hi fellas is there a way to use network render for one image? Mean like for anim when idle computer start to compute next image but using tiles so the idle computer will start the next tile.  I know its possible on one computer using CUDA CPU + GPU that idle HW start next one but is there a way to use second computer? I mean in Cycles for sure.  I think there has to be a way because using SheepIt render farm You could divide every single image into multiple "instances" and these are rendered on different computers as far as I know.  I dont want to combine two images with different seeds and half samples like its answered in many different questions but wonder if someone know the system used on the farm mentioned above.  Sincerely, Jan  REM: If Im not mistaken V-Ray could be used like this? So Cycles?


How does one calculate the age of a Time Lord?   Is it the time since he was born until the canon present? Or is it the sum of the days he lives?  Because if it is the latter, he could live billion of years in five seconds.  So, do they really have an age? Does The Doctor really have an age? Or does he say he is 900 or 2000 years old just to prove a point?


After entering 'y' the code should again ask for the choice but it does not happen

import java.util.Scanner; public class SwitchCase {      public static void main(String[] args) {          Scanner sc=new Scanner(System.in);          String ch="NULL";         do          {             System.out.println("Enter your choice:");             String str=sc.next();             switch(str)           {              case "Add":             {             System.out.println("Enter 2 nos:");             int a=sc.nextInt();             int b=sc.nextInt();             int c=a+b;             System.out.println("Adiition is:"+c);             break;             }              case "Sub":             {                 System.out.println("Enter 2 nos:");                 int a1=sc.nextInt();                 int a2=sc.nextInt();                 int a3=a1-a2;                 System.out.println("Sub is:"+a3);                 break;              }             case "Multiply":             {                 System.out.println("Enter 2 nos:");                 int a1=sc.nextInt();                 int a2=sc.nextInt();                 int a3=a1*a2;                 System.out.println("Sub is:"+a3);                 break;             }              case "Divide":             {                 System.out.println("Enter 2 nos:");                 int a1=sc.nextInt();                 int a2=sc.nextInt();                 int a3=a1/a2;                 System.out.println("Sub is:"+a3);                 break;             }             case "Fib":             {                 System.out.println("Enter the range:");                 int n=sc.nextInt();                   if (n == 0)                  {                      System.out.println("0");                  }                   else if (n == 1)                   {                        System.out.println("0 1");                  }                  else                   {                        System.out.print("0 1 ");                        int a = 0;                        int b = 1;                        for (int i = 1; i < n; i++)                        {                            int nextNumber = a + b;                            System.out.print(nextNumber + " ");                            a = b;                            b = nextNumber;                        }                              }         }     }         System.out.println("Do you want to continue? y or n");       ch=sc.next();         }           while(ch=="y");      }  }   After the while loop,when "y" is entered by user,it should ask "Do you want to continue" but the same does not happen.I debugged the code,it runs fine till "Do you want to continue?" But after that :  source not found error comes, when debugged in eclipse


Prove that the series $a_n = $ $2^n \over n!$ converges to 0.  I am trying to find a variable that will be bigger than $2^n\over n$ , with no luck.  Any help, besides using binoms? Thanks in advance!!!


Riemann zeta function on the line Re(s) = 1

How can I prove that for $s \in \mathbb{C}$, with real part of $s$ being equal to 1,  \begin{equation} \sum_{n=1}^{\infty}\frac{1}{n^{s}} \end{equation} diverges?  Thanks a lot!


Negative correlation coefficient but positive regression coefficeint

In one of my research projects, I found a negative correlation between $X$ (a regressor of interest) and $Y$ (an outcome variable). In the regression model, I found that the coefficient of $X$ is positive after controlling for other variables in the regression model.   What could be the explanation of the negative correlation in the unadjusted model? I expected that a negative correlation would yield a negative regression coefficient in the multivariate model.


Batch script to resize height of all layers to same height but keeping their original aspect ratio

I have hundreds of product image layers and I am trying to resize them all to the same height (ignoring the width) and retaining their individual aspect ratio's.  Is there a script available that does this? Or a feature I am unaware of?  Thanks!


Function to modify struct does not update struct

I am trying to make a tic-tac-toe game. I made this function which supposed to update the board values (insert 'X' or 'O') but the struct simply doesn't update, it shows that the values stay the same as initialized.  #include <iostream>  struct Board {//initializes a struct     char A1 = ' ';     char A2 = ' ';     char A3 = ' ';     char B1 = ' ';     char B2 = ' ';     char B3 = ' ';     char C1 = ' ';     char C2 = ' ';     char C3 = ' '; };  struct Board InputSignInStruct(char num, char letter, struct Board b,char sign) {//a function which is supposed to update values in the struct     if (letter == 'A')     {         if (num == '1')             b.A1 = sign;         if (num == '2')             b.A2 = sign;         if (num == '3')             b.A3 = sign;     }     if (letter == 'B')     {         if (num == '1')             b.B1 = sign;         if (num == '2')             b.B2 = sign;         if (num == '3')             b.B3 = sign;     }     if (letter == 'C')     {         if (num == '1')             b.C1 = sign;         if (num == '2')             b.C2 = sign;         if (num == '3')             b.C3 = sign;     }     return b; }  int main() {     struct Board b;     char letter,num;     std::cin>>letter>>num;     char sign;     std::cin>>sign;     b = InputSignInStruct(letter, num, b, 'X');//should return the updated struct but it doesent update }


I want to place the n from the \sqrt[n]{\rho} command in a more visible position and make it bigger too.    MWE:  \sqrt[n]{\rho}


I just read this sentence and was wondering if it is okay to write it like this.     You can use your device worldwide, as if it was directly connected to your   PC.   Are there better alternatives for writing this sentence? Maybe:     You can use your device worldwide, just like it is directly connected to your   PC.


I have downloaded and burned the .iso on a MAC for installation on a Windows XP laptop that won't do much more than boot up. I am able to open the folder (from the DVD) on the XP laptop and it looks good (many folders and files). When I try to boot from the DVD, it gets caught up in repeating errors that say:  [###.###].[drm] nouveau 0000:01.00.0: Failed to idle channel 1   It will follow with the same message to channel 2. This is repeating until I power off the computer.  The computer on which I'm trying to boot the Ubuntu DVD is a Dell Inspiron E1705. The graphics card is not known. When I go into the display properties and look at the adapter type is says "VgaSave", manufacturer: Unknown. I do have obvious display issues but also can't connect to the Internet from this device either to attempt to load new drivers.  Is it possible that I have burned the wrong .iso file? Has anybody seen this?  It is a Dell Inspiron E1705. The graphics card is not known. When I go into the display properties and look at the adapter type is says "VgaSave", manufacturer: Unknown. I do have obvious display issues but also can't connect to the Internet from this device either to attempt to load new drivers.


In Fullmetal Alchemist when Ed goes to disprove to Rose the Sun God's "miracle" to bring humans back to life by proving that science (in the form of Alchemy) can create people by saying     Water (35 L), Carbon (20 kg), Ammonia (4 L), Lime (1.5 kg), Phosphorous (800 g), Salt (250 g), Saltpeter (100 g), Sulfur (80 g), Fluorine (7.5 g), Iron (5 g), Silicon (3 g) and trace amounts fifteen other elements.   I am wondering, is this composition true in real life? if so what are fifteen trace elements?


Limit $\lim_{n \to \infty} \frac{n!}{n^n}$

$$\lim_{n \to \infty} \frac{n!}{n^{n}}$$    Attempt:  $$n!=n\left( n-1 \right)\left( n-2 \right)...\left( n-\left( n-1 \right) \right)=n^{n}+...$$  $$\lim_{n \to \infty} \frac{n!}{n^{n}}=\lim_{n \to \infty} \frac{n^{n}+...}{n^{n}}=\lim_{n \to \infty} \frac{1+...}{1}=1+\lim_{n \to \infty} \ ...=1$$    I based this on the fact that $n$ is the highest power. The answer's meant to be $0$ though.


$$\sum_{i=0}^{n-1} ar^i = \frac{a(r^n-1)}{r-1}$$ for  $r \in \mathbb R, r  \ne 1, n \ge 1 $  i. Show true for $n=1$ $$\frac{a(r^1-1)}{r-1} = a$$  ii. I am stuck on how to do the second part of the proof, and the logic behind it.


Can you do Top-K frequent Element better than O(nlogn) ? (code attached)

Recently encounter an algorithm question which asked to do Top-K frequent Element better than O(nlogn). I implemented it using C++ and did some complexity analysis. I feel it is NOT possible to do better than O(nlogn). Attached my code and complexity analysis in lines. I used map. I think unordered_map in practice will do better but ,for worst case analysis, unordered_map is worse than map due to hash conflict. It would make the first block to O(n^2) in worst case.  Description: Given a non-empty array of integers, return the k most frequent elements. For example, Given [1,1,1,2,2,3] and k = 2, return [1,2]. Note:  You may assume k is always valid, 1 ≤ k ≤ number of unique elements. Your algorithm's time complexity must be better than O(n log n), where n is the array's size.  Many solutions from google search are using hash table and those solutions assumed inserting operation to a hash table is O(1) which, in my opinion, is not true. Because in worst case, hash table produce O(n^2) for insert operation when hash conflict happens. Big O notation is all about worst case analysis.  vector<int> topKFrequent(vector<int>& nums, int k) {         map<int, int> _map;         vector<int> result;          //complexity: O(nlogn)         for(auto n : nums) {             // map.find() has O(logn)             if (_map.find(n) != _map.end()) {                 // have seen before                 _map[n]++;             } else {                 // new one,                  _map[n]=1;             }         }          //complexity: O(n)         vector<pair<int,int>> v;          for(auto itr = _map.begin(); itr != _map.end(); ++itr) {             v.push_back(make_pair(itr->first, itr->second));         }          // complexity: O(n)  (build a heap)         auto f = [] (pair<int,int> p1, pair<int,int> p2)  { return p1.second < p2.second; };         make_heap(v.begin(), v.end(), f);           // complexity: O(k*logn)         while(k) {             result.push_back(v.front().first);             pop_heap(v.begin(), v.end(),f); // delete heap from binary tree O(logn)                                             //    1. swap root with last leaf O(1)                                             //    2. find right place for last leaf             v.pop_back();             k--;         }          return result;      }   Thanks in advance for your response.


How can I calculate $$\sum_{n=1}^{+\infty}\frac{1}{n\sqrt{n+1}+(n+1)\sqrt{n}}$$   ? Can someone help and explain too?


Can an electrolytic capacitor be charged reversed bias by a small voltage?

In this monostable circuit the C1 capacitor is reverse biased. When T1 is closed and C1 is discharged what will happen on the right side of C1?   Will it charge up to 0.6 volts so that T2 can be opened and then discharge again over the base-emitter line and than charge through R2?   That would mean that the polarized capacitor could be loaded reverse biased. Is that true?


Special characters not working inside where clause

This code, which is inside a Wordpress (Php Code Plugin) was working yesterday and suddenly today doesn't seem to work anymore. I can't see exactly what's wrong with it.  $sql = $db->prepare('SELECT id_loc FROM `brands` WHERE country = :country_name GROUP BY id_loc'); $sql->bindParam(':country_name', $country_name); $sql->execute();   When the given country is "España", it returns no result. Others like "Túnez" work pretty well even though it has an accent. If I write the query literally without binding the param, it also works. My tables collation is latin1_spanish_ci:  $sql = $db->prepare('SELECT id_loc FROM `brands` WHERE country = "España" GROUP BY id_loc');   Can somebody bring some light over this?


What's the difference between port status "LISTENING", "TIME_WAIT", " CLOSE_WAIT" and "ESTABLISHED"?

I use netstat to check my port status.  I was wondering what's the difference between port status LISTENING, TIME_WAIT, CLOSE_WAIT, FIN_WAIT1 and ESTABLISHED?


image of polynomial map is not an algebraic set

I am doing an exercise about algebraic geometry, where the exercise  tell us to provide example of the image of polynomial map $f:\mathbb{C}^{m}\rightarrow \mathbb{C}^{n}$ that is not an algebraic set. But I am thinking that the image of every polynomial is $\mathbb{C}$ thus every polynomial map is surjective. What have I misunderstand?


Best way to cut a hole through an object?

I need to create a cylinder, cut in half, with a hole cut out of it. I'm very new to Blender, and I'm sure that there are many ways to achieve the same thing, but I used a boolean modifier to remove the hole from the cylinder. The problem is that in the shape that I have, after selecting smooth shading, there are some unwanted diagonal lines above and below the hole that you may be able to see in the image.   My question is, is there a more efficient way to do this without a Boolean modifier? I have heard that Boolean modifiers are not a great tool as they can result in 'bad topology' so I would appreciate it if someone could suggest a better way to do this. I would also like to know if it is possible to have the smooth shading without these strange lines around the hole.  Thanks!


Why does a balloon filled with air weigh more than an empty balloon

A common experiment to demonstrate that air has weight is to weigh a deflated balloon and an inflated one. The deflated balloon gives a lower reading on the balance and hence we conclude that air has weight.   However, if we think about it, what we have done is just 'encase' a part of the atmosphere inside the balloon. When the air was outside the balloon it had no 'weight'. If we hold a weighing machine in the air, it reads $0$. Why does putting the air inside a balloon suddenly give it mass?  In other words, if the air inside the balloon exactly displaces its mass of air. So the force due to gravity on it must be cancelled with the upthrust due to buoyancy. How then does the balloon filled with air weight more?


Flagged needed mod attention, question closed by mod, but flag declined?

I couldn't find anything specific regarding this as all flag questions seem to address the flag in particular, that said:  I usually wouldn't post anything like this as it is just a flag, and the question was closed anyways - however, this seems to happen a bit with my declined flags.   For this exact case, the question was:   And I flagged it for moderator review. I then see that the flag was declined by "declined - a moderator reviewed your flag, but found no evidence to support it", and when looking at the question, I see:     closed as not constructive by tjameson, Álvaro G. Vicario, J. Steen, Rikesh, Andrew Barber♦ 19 mins ago   And while I can understand a question being closed by the close votes of users with enough rep, it was also closed by a moderator.  I flagged specifically "needs moderator attention".  Granted I chose other with "Asking to sabotage code" and then was slightly verbose as I wasn't quite sure how to mark it, but it shouldn't have affected the fact that it did need moderator attention, and was closed by a moderator as well.  My question in short is "What?" and "How does that happen?"  EDIT  Entire flag message:     Asking to help sabotage code. Not sure if I should have marked it this way or "Not Welcome in out community" as I believe it fits that title, though not really it's description. ^^   Flag decline reason:     declined - a moderator reviewed your flag, but found no evidence to support it    Flag type:     Need Moderator Attention -> other


How to capture all lines but avoid lines containing a particular word or pattern? Is capturing with negative lookaheads possible?

Data is from a table in a pdf which is extracted by converting to text(using pdftotext). This is an example of the kinda data that from which im trying to capture all lines in python starting with district1 till the line with Total(included), but doesn't include any empty lines(^\n) or lines with keywords like Call or Office.   Regex I've tried  Applied a DOTALL flag too.  I tried to capture in python like this : re.findall(r'District.*icts(.*Total.*?\n|\r)',input,re.DOTALL)  District.*icts(.*Total.*?\n|\r)   The above captures(not simply match) everything in between district1 and Total(inclusive). But I want remove the captured lines or don't capture lines which contains keyword Call or Office. So i tried to apply a negative lookahead, but it didnt work either:  District.*icts(((?!Call|Office|^\n).)*Total.*?\n|\r)   Been with this problem whole day. I'm not getting any other idea on ignoring those lines and capturing the rest. Any help would be appreciated.  POSSIBLE VARIATIONS OF INPUTS  ---dont capture this line----             District    No. of positive cases admitted        Other Districts district1                           7                        1 district4 district2                           6 district3                           7                         -                Call Centre:12323, 132123                                    Office:212332122 , 1056   district4                           131         Total                       263 ---dont capture this line----   ---dont capture this line----             District    No. of positive cases admitted        Other Districts district1                           7                        1 district4 district2                           6                Call Centre:12323, 132123                                    Office:212332122 , 1056 district3                           7                         -    district4                           131         Total                       263 ---dont capture this line----   ---dont capture this line----             District    No. of positive cases admitted        Other Districts              Call Centre:12323, 132123 district1                           7                        1 district4 district2                           6                                       Office:212332122 , 1056 district3                           7                         -    district4                           131         Total                       263 ---dont capture this line----   Required Capture  district1                           7                        1 district4 district2                           6 district3                           7                         -   district4                           131         Total                       263


Re-entering UK on ICT Tier 2 with four days left for visa to expire

I am in UK on a multiple entry short term ICT-Tier-2 visa which expires in mid-April 2017. My work assignment last day is 31st March 2017. After that I plan to go for a one week holiday to the Netherlands to meet my brother.  If my UK visa ends on 14th April and I return from the Netherlands on 8 or 9th April will I be barred from entering the UK?  The reason I want to return to UK is that my return travel from UK to India will be arranged by my employer.


I can change the command prompt string and color from the command line but not from a bash script

If I execute either of these commands from a command prompt, I get what I want, but from a bash script, it doesn't work: PS1="\e[0;34m${title} $ \e[m" # Prompt text Blue export PS1="\e[0;34m${title} $ \e[m" # Prompt text Blue  e.g.,  I can change the window title from a script but not the command prompt. How can this be done from a bash script?


Does Process Builder run with System permissions or User permissions?

Regarding field-level security, does Lightning Process Builder run as system-level permissions or user?  That is:   Can I trigger an update to a field that the current user cannot edit? Can I filter based on a field the current user cannot read?


Deriving Time Complexity from an algorithm

I am trying to learn about time complexity of an algorithm. My professor has pushed it beyond Big O and wants us to be able to derive an algorithm to a mathematical function. I am having a hard time conceptualizing how this is done and was looking for help. In my class notes, a selection sort algorithm was provided (as shown in the code below). The notes asked the following question: "Derive a function f(n) that corresponds to the total number of times that minIndex or any position of nums is modified in the worst case. Now the notes tell me the answer is f(n)= 1/2n^2 + 5/2n + 3. I was wondering if anyone could explain how this occurs.  My professor told us to count the operations in the inner loop and work our way out. so I believe that at worst case in the inner loop the if statement always executes, this would mean we run the loop n-i-1 times, I get these values by taking n (the boundary that the for loop has to be less than and subtracting it by the starting condition (i+1). Then I look at the outer loop and I see it goes from i until it reaches n-1, so it could be written as (n-1)-i or just like the inner loop, n-i-1. Looking further there are three modifications in the outer loop so we get (n-i-1)+3 ( could I write it as (n-i+2)?  The number of modification at the worst case for the inner loop: n-i-1  The number of modifications at the worst case for the outer loop: (n-i-1)+3  now I would like to know how do you go from counting the two different modifications done and becoming f(n)= 1/2n^2 + 5/2n + 3.   public static void selectionSort(int[] nums) {          int n = nums.length;         int minIndex;          for(int i = 0; i < n-1; i++) {             //find the index of themin number.             minIndex = i;              for(int j = i+1; j < n; j++) {                 if(nums[j] < nums[minIndex]) {                     minIndex = j;                 }                 int temp = nums[i];                 nums[i] = nums[minIndex];                 nums[minIndex] = temp;             }         } }


Does a cooling object lose mass as it radiates?

Assume we have a red hot cannonball in space. It starts off with mass M at 1000K. Later it has cooled by radiation to 100K. Has the mass decreased?


How to automatically start programs in specific workspaces on start up

I would like to add a command at the rc.d system by which, when ubuntu starts it will run different program at different workspaces.I.e:workspace 1: chrome,workspace 2:thunderbird.How could this be achieved?Is there any tool?


Why does len(grid) vs for i in range(len(grid)) make a difference?

For the code below, which is used for Leetcode #64 Minimum Path Sum, I tried to make the cache grid using " len(grid)" and it does not work for all test cases, but if I do "for i in range(len(grid))" it works perfectly. I'm wondering why this makes a difference if the grid has the same dimensions either way. My code works for the first 2 cases but fails at the third, the code that uses range is accepted in Leetcode. Thank you. class Solution:     def minPathSum(self, grid: list) -> int:         # cash = [[-1] * len(grid[0])] * len(grid)         cash = [[-1] * len(grid[0]) for i in range(len(grid))]         return self.recursion(grid, 0, 0, cash)      def recursion(self, grid, y, x, cash):          # first we check if the space is valid         if self.check(grid, y, x) is not True:             return 0          # then we check if that space has already been cached, if it has, we just return that space         if cash[y][x] != -1:             return cash[y][x]          # this is where the space currently is on the grid         current = grid[y][x]         # now check if we are currently at the rightmost or bottommost perimeters of the grid         if y == len(grid) - 1:  # if at rightmost, have to go down             cash[y][x] = current + self.recursion(grid, y, x + 1, cash)         elif x == len(grid[0]) - 1:  # at bottommost, have to go right             cash[y][x] = current + self.recursion(grid, y + 1, x, cash)         else:  # if the current value is not at a bottom or right perimeter, keep going             cash[y][x] = current + min(self.recursion(grid, y, x + 1, cash),  # compare the right block                                        self.recursion(grid, y + 1, x, cash))  # to the down block         print(cash)         return cash[y][x]      # check if this space exists in the grid using the grid boundaries     def check(self, grid, y, x):         return len(grid) > y >= 0 and len(grid[0]) > x >= 0   grid = [[1,3,1],[1,5,1],[4,2,1]] print(Solution().minPathSum(grid=grid))  grid = [[1,2,3],[4,5,6]] print(Solution().minPathSum(grid=grid))  grid = [[1,2],[1,1]] print(Solution().minPathSum(grid=grid))


Prove or give a counter example $ \sum_{n=1}^{\infty } a_{2n} \ and \sum_{n=1}^{\infty } a_{2n-1} $ converge than $ \sum_{n=1}^{\infty } a_{n} $

claim:  if$$ \sum_{n=1}^{\infty } a_{2n} \  and \sum_{n=1}^{\infty } a_{2n-1} $$ both converge than  $$ \sum_{n=1}^{\infty } a_{n}  $$ converge. I managed to prove that this claim is true if $a_n \ge0$ but, what about general series ?  I got the same issue with this claim :  $$ \sum_{n=1}^{\infty } |a_{n}| converge  $$ than  $$ \sum_{n=1}^{\infty } a_{n}\ ^ 2  $$ converge. again ,  managed to prove that this claim is true if $a_n \ge0$.  Thanks for helping.


Word for something that used to be popular but not anymore

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Not able to install packages in Ubuntu 11.04

I installed Ubuntu 11.04 (My PC is very Old and have low configuration 11.04 working well),but when i trying to install restricted extra codec,adobe flash getting error message "counld read from source"  i  software center.  Aslo when i am trying to install from command line it saying broken dependencies  The following packages have unmet dependencies:  When I executed the command apt-get -f install' i showing no packages to install  0 Installed 0 upgraded.  How to resolve the this issue


Should I disconnect my MacBook Pro's power cord when the battery is fully charged?

My friend told me that I need to disconnect the power cord when the battery is fully charged. Otherwise, I will shorten the life of the battery.  Other people say you should drain it once a month or point out that for long term storage, you should charge it to 50% and then periodically (3 to 6 months) bring it back to 50% and store it again.  I am going to use my laptop at home 90% of the time. So, I plan to have the power cord connected all the time.  I'd prefer to just plugging in my MacBook Pro and letting it be on charge long term and occasionally taking it away from the charger when I'm not at home or my desk.  Are these specific recommendations worth the inconvenience?


I have two operating systems, ubuntu and backtrack 5. I no longer need BT5. How do I remove/uninstall BT5 without losing any data of Ubuntu ?  Edit 1: After I delete the BT5 partition how do I extend the partition to use the empty space or does it happen automatically ?


number figures and tables together with one label name

I would like to label my figures and tables continuously using S.I, S.II, S.III, etc in the caption of both, figures and tables.  I can change the figure and table caption to S.I, ... by   \renewcommand{\tablename}{S.} \renewcommand{\figurename}{S.} \renewcommand{\thetable}{\Roman{table}} \renewcommand{\thefigure}{\Roman{figure}}   but this still counts figures and tables separately. S.I thus exists twice, once for the first figure and once for the first table.   How can I avoid this? Thank you!


Parse file length to user friendly format

I am using the following in C# to get the length of a file  long length = new System.IO.FileInfo(path).Length;   How can I nicely parse the file into same as Windows displays it:     2.92 MB (3,072,000 bytes)


Sierra Automator KeyboardViewer App Shortcut

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I'm taking a class in Probability Theory, and I was asked this question in class today:     Given disjoint events $A$ and $B$ for which $$ P(A)>0\\ P(B)>0 $$ Can $A$   and $B$ be independent?   My answer was:     $A$ and $B$ are disjoint, so $P(A\cap B)=0$.   $P(A)>0$ and $P(B)>0$, so $P(A)P(B)>0$.   $P(A\cap B)\not =P(A)P(B)$, so $A$ and $B$ are not independent.   However, I was told that I am wrong and we cannot know whether or not $A$ and $B$ are independent from the given information, but I did not receive a satisfactory explanation. Is my argument valid? If not, where do I go wrong?


Allow the author to delete their own question after closure, if other rules permit it

I've read through a few "I want to delete my own question" threads on  already, and haven't found any that particularly cover this case.  I asked a question recently on :    This was voted closed as a duplicate of this question:    Since the latter question was obviously an appropriate duplicate, and my question had no votes or answers whatsoever, I decided I would just delete it.  But then, I was greeted by this error:     To allow for possible reopening, you may delete in 2 days     This all happened within hardly 20 minutes of me posting the question in the first place.  I fail to understand the point of this.  Perhaps if there were some up-votes or answers to the question, it might make sense.  However, as it stands, we now have a question with:   No votes whatsoever (up or down). No answers. Only a single (and largely irrelevant) comment not made by the OP. Five 3k+ rep users agreeing it is duplicate and therefore superfluous. The OP expressly desiring the question to be deleted, implying:   The OP has probably reviewed the duplicate question, and found their answer there. The question holds no further value to the OP. The OP agrees (with the close-voters) that the question provides no added value to the community.    At this point, what good reason could there be for disallowing the OP to delete their own question?  Could the system be modified to permit this?


How can I create a "rain drops on camera lense" effect with the HDRP?

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Do Samuel Jackson, Natalie Portman, Idris Elba and Benedict Cumberbatch exist in the MCU?

In Captain America: Winter Soldier, Steve looks at a list of pop culture items to catch up on. Two of the items on the list are Star Trek and Star Wars. Let's say he and Thor would sit down together and binge-watch all the ST and SW movies. They would both be confused and surprised to see Mace Windu who looks and sounds uncannily like Nick Fury. Thor would find it a little disturbing to see Queen Amidala/Padme, and would also be troubled to see Idris Elba's character in Star Trek:Beyond (and would find it most distressing of all to see himself playing George Kirk in Star Trek!). And, depending on when they do this, they would both be shocked to see Doctor Strange as the villain of Star Trek:Into Darkness.  One could suggest that the in-universe explanation is that they live in a more ideal world where the Prequels never happened. Or perhaps the movies exist, but with different actors. What other possibilities are there, and has Marvel or Disney ever addressed this and given an official in-universe explanation?


What is the Difference between will resume and will be resumed?

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