Tell pgfplots to put tick labels between tick marks

Is it possible to tell pgfplots to put tick labels between the tick marks instead of at the tick marks?  MWE:  \documentclass[margin=5pt]{standalone}  \usepackage{tikz} \usepackage{pgfplots}  \begin{document}      \begin{tikzpicture}          \begin{axis}[             width=5in,             height=3in,             axis lines=middle,             scaled ticks=false,             xtick=\empty,             xmin=0,             xmax=3,             extra x ticks={0,1,2,3},             extra x tick labels={low,high,med},         ]          \addplot [mark=*,draw] coordinates {(0.5,2) (1.5,4) (2.5,3)};          \end{axis}     \end{tikzpicture}  \end{document}   Result:    I can do it manually by adding  xticklabel style = {xshift=1.9cm,align=center},     but this seems unsatisfying, unreliable, and requires too much trial and error.


Is sum of two square summable sequences is again square summable?

I am trying to prove the set $W=\{(a_n) | \sum a_n^2 <∞\}$ is subspace of vector space $V=\mathbb{R}^∞$ (vector space of all sequences of real numbers)  For this, clearly as $0^2+ 0^2+...=0 <∞$ Hence (0) is in $W$.   Further, if $(a_n), (b_n) \in W$ then we have $\sum a_n^2<∞$ and $\sum b_n^2<∞$.   How can I prove $\sum (a_n+b_n)^2<∞$


A word for feeling simultaneously happy & sad

I'm looking for a word that means feeling both happy and sad at the same time. Here's a sentence I'd like to use it in:     "At least we got one vote," she said with a (word I'm looking for) smile.


I am running a chroot on chrome os and my Ubuntu version is 16.04.6. Can I update to a newer version?

I am on a Chromebook and am running a chroot. My Ubuntu version is 16.04.6 I want to upgrade to a newer version. Is this possible? If I look online, it says to open a program called update manager. For me, that program does not exist and when I type in the command to get that program, it says HTTP quit unexpectedly. Can anyone help?


I am looking for a utility to dump the memory of a running process that I can then examine for strings.  In the past I have used pcat from The Coroner's Toolkit, but I am having a hard time finding a version that will work on RHEL 6.4 64bit. Given that TCT is in its twilight, is there a better utility to do this?  Edit: I am looking for a utility. I will use scripts to get what is needed if necessary, but I was hoping for a standalone tool that I could get from the standard repo that will allow an untrained user to grab the process's memory.


Unable to boot into Ubuntu 20.04.1, after installing along side Win 10

I just installed Ubuntu 20.04.1 LTS however the laptop boots up in Windows 10 without any option to boot into Ubuntu. I am newbie and do not get much technical side of things – is there anything that could help explain in simple language as to how I can fix the issue please ? Below is the current boot order Yes, see below is the ‘UEFI Boot Order’ USB Flash Drive/USB Hard disk OS boot manager USB cd/dvd rom drive ! network Adapter Secure boot is disabled.


$A$ is a matrix.  $$A^TA=0 \iff A=0$$How can I prove this?  Please help me.


Is it possible to use the align environment while suppressing the auto \newline?  I have a problem with the following command:  \begin{lemma}      \begin{align*}   a+b &= c \\\    &=d      \end{align*}   \end{lemma}   I want the first equation a+b=c to be on the same line as Lemma but instead TeXstudio put it on the next line. I tried using aligned enviroment instead but it gave funny result.  Could anyone please suggest me how to fix the problem?


Are international driving licences really necessary for any country?

When I first started travelling internationally about 20 years ago I was young and naive and bought an international driver's license for my trip to the United States.  Then I discovered that it was not at all needed. All that was needed was a licence from my own country with a photo. At that time photo licences were relatively new in Australia.  So my question is, is this the case everywhere or are there some countries which really do not permit foreigners to drive without an international licence?  (I don't need a full list of countries as an answer, just a yes or no with a couple of examples is fine)


$\operatorname{Supp}(M)=V(\operatorname{Ann}M)$ if $M$ is finitely generated

Let $A$ be a commutative ring with 1, set $V(\frak a)=$ the set of prime ideals of $A$ that contains $\mathfrak a$, and write $\operatorname{Supp}(M)$ for the support of the $A$-module $M$. We always have $\operatorname{Supp}(M)\subseteq V(\operatorname{Ann} M)$; if $M$ is finitely generated then the other inclusion also holds. Assume now $M$ is finitely generated. It is ok to show that if $M_{\frak p}=0$ then $\operatorname{Ann} M\cap A\setminus\frak p\ne\varnothing$, I was just wondering if the following procedure for showing this inclusion is flawed:  Suppose $\frak p$ contains $\operatorname{Ann} M$. Since $M$ is finitely generated we have the equality $(\operatorname{Ann} M)_{\frak p}=\operatorname{ Ann} (M_p)$, hence the annihilator of $M_{\frak p}$ is contained in maximal ideal of $A_{\frak p}$ and is therefore different from (1), so $M_{\frak p}\ne0$.


JavaScript scope chain: why is a * 3 = 5?

I could not understand the scope chain. Why does a * 3 equal to 5?   function doSomething(a) {   function doSomethingElse(a) {     return a - 1;   }    var b = 0;    b = a + doSomethingElse(a * 3);   console.log(b) }  doSomething(2)


Force on a test charge placed at the center of a 13-sided regular polygon?

Assume a test charge with charge $Q$ is placed at the center of a 13-sided regular polygon, the vertices of which are charges with equal charge $q$. What is the electrical force on the center charge?  To start we write this as our electrical force... $$ \vec{F}_{Q} = \sum^{13}_{n} \frac{1}{4\pi\varepsilon_{0}}\frac{qQ}{R^{2}} \left(cos\left(\frac{2n\pi}{13}\right)\hat{i} , sin\left(\frac{2n\pi}{13}\right)\hat{j}\right)  $$   and with some simplification we get... $$ \vec{F}_{Q} = \frac{1}{4\pi\varepsilon_{0}}\frac{qQ}{R^{2}} \left\{1-2cos\left(\frac{\pi}{13}\right) + 2cos\left(\frac{2\pi}{13}\right)-2cos\left(\frac{3\pi}{13}\right) + 2sin\left(\frac{\pi}{26}\right)-2sin\left(\frac{3\pi}{26}\right)+2sin\left(\frac{5\pi}{26}\right), 0\right\}$$ ...more simplification... $$ \vec{F}_{Q} = \frac{1}{4\pi\varepsilon_{0}}\frac{qQ}{R^{2}}  \left\{ 1.11022\times10^{-16}, 0 \right\} $$ Now we have an electrical force on the test charge, however, in a ring of equidistant charges such as the one mentioned above, shouldn't the $\hat{i}$ component be equal to zero? Does anyone have any ideas as to why I'm getting a non-zero number for my $\hat{i}$ component?


What can I include in 3rd-party content?

What WotC 5e D&D content am I and am I not allowed to use in published 3rd-party content? Core books? Books like Xanathar's and Volo's? Unearthed Arcana? How do I avoid plagiarism, copyright infringement, etc?  Right now, I want to provide on my site/blog short campaign settings for dungeon masters to use as starting ideas for their games. If I create enough, I'm considering package them together in a PDF and sell them on something like DriveThruRPG.


Unable to add elementaryOS repository its "insecure"

I am trying to add an elementaryOS repository on ubuntu 20.04 to install Pantheon but this is what it says: sudo apt-add-repository ppa:elementary-os/stable  E: The repository 'http://ppa.launchpad.net/elementary-os/stable/ubuntu focal Release' does not have a Release file. N: Updating from such a repository can't be done securely, and is therefore disabled by default. N: See apt-secure(8) manpage for repository creation and user configuration details.


which one is correct? said to not go VS said not to go

I learned "not to go" is right but sometimes I could find "to not go" what's correct? ex) She said not to go there. ex) She said to not go there.


I want to reinstall windows 7 on my machine.  I read this from      Windows, it’s up to the PC manufacturer to provide a recovery partition or recovery discs. Most manufacturers don’t include Windows installation discs with their computers.      partition, run your manufacturer’s recovery tool to reinstall Windows. On many PCs, you’ll have to press a key during the boot process to access the recovery tool. This key may be displayed on your screen. It should also be printed in your computer’s manual.      disc, you can also insert it in your computer’s optical drive and boot from it to begin reinstalling Windows. You’ll end up with the manufacturer’s like-new Windows system on your drive.   Do I have to find a windows 7 on piratebay in order to install it now? I don't have a windows disk.


Copying content from one directory to another

I'm copying a lot of folders/subdirectories from one network drive to another, however, the names of these files aren't known and I only want to copy the contents of the folders that have a name match.  Ex: srcdir has folders f1, f3, f4, f9 and destdir has folders f3, f5, and f9: since the names of folders f3 and f9 match, the contents (files and subdirectories) of f3 & f9 found in srcdir will be copied into their respective folders in destdir.   I've tried using xcopy but it only copies the files, and I've also tried   robocopy C:\test1 C:\test2 /u /s   but that skips over everything.  How would I go about copying the contents of a folder from the source network drive into its matching folder in the destination drive? Here's the code I have so far:  @ECHO OFF setlocal EnableDelayedExpansion for /d %%i in ("C:\test1\*") do (   for /d %%j in ("C:\test2\*") do (     set srcdir="%%~nxi"     set destdir="%%~nxj"     if !srcdir! == !destdir! ( robocopy C:\test1 C:\test2 ) else (echo Notsame!)     echo %srcdir%     ping 130.11.160.2   ) )


How can I install Ubuntu alongside Windows 7?

How can I install Ubuntu alongside Windows 7, because the option to install Ubuntu alongside Windows 7 does not show me? I want to install the hard disk partitioning manually. How can I do it?


I am writing a bash script to move all images into a central file.  I create the list of image files with:  img_fil='/home/files/img_dump.txt' locate -i image | grep \.jpg > "$img_fil" locate -i image | grep \.jpeg >> "$img_fil" locate -i image | grep \.gif >> "$img_fil" locate -i image | grep \.tif >> "$img_fil" locate -i image | grep \.png >> "$img_fil"   But when I start processing the dump file for this, most of the paths contain blanks so this does not work:  while read -r fline do    if [ ! -e "$fline" ]; then       echo "F=> $fline"       mv "$fline" "$img_dir"    else       fpath="$(dirname $fline)"       fname="$(basename $fline)"       echo "F=> $fname P=> $fpath"    fi  done   The dirname and basename always parse at the blanks so will not process right.  How do I get this to work?


Why not have the gears inside the bottom bracket?

Looking into an IGH it seems the biggest disadvantage is having a huge amount of rotating mass. I've seen one handmade bike where the IGH sits above the bracket, inside a carbon fibre shroud around the place some bikes have rear suspension. There are two chains, one driving the IGH and another to drive the rear wheel.   Why not have an internally geared bottom bracket where the cranks drive the input shaft and the crank ring rotates at a ratio selectable by the gear lever?   Then the rear wheel could have a single drive wheel driven by a chain or belt and a lightweight hub just solid enough to mount the spokes and disc. Then you could have mud-free gearing while reducing rotating mass even below what you have with a conventional cassette... and given that you have thrown out the bottom bracket the overall weight gain would be less.  Quite a job for the home builder to adapt an existing hub I guess but it should be possible.


how do you install ubuntu touch as a desktop environment?

On another question someone mentioned that you could install ubuntu touch as a desktop environment for laptops with touchscreens. I have not been able to find this option. Is there a way I could try this out?


"add feature" tool QGIS 2.0 - polygon fill blocks view of what I want to digitize

How can I change the settings on the vector "add feature" tool so the tool fill doesn't block my view of what I want to digitize?  This problem popped up after I upgraded to QGIS 2.0   QGIS 2.0 Macbook Pro  OS 10.9


Why is my animation not correctly keeping location and rotation?

I am sure that I set the keyframes location and rotation correctly, but it doesn't behave in that way. I can't find any solutions in Google nor Youtube.


Where to download .osm files and how to convert it to .xml?

I am new to deal with OSM data, and I want to download only .osm files not .pbf. I tried geofabrik.com but it provides .osm.pbf file format   where can I download .osm files? is there any recommended way to convert .osm files to .xml?


Hard drive shared between Linux and Windows

I have a dual boot system and an empty hard drive. I want to access this drive from both systems. How can I achieve this?


I am trying to retrieve list items using date range based on date column. It implicit both 'Fromdate' and 'Todate'.My CAML query is also querying on two other conditions as well. I am using the below query but it is not retrieving the data.when I remove the date range from query data is retrieved fine. But i want date range as well in my query how would i do this. Little help would work for me.   camlQuery.set_viewXml('<View><Query><Where><And><And><Neq><FieldRef Name="ID" /><Value Type="Number">0</Value></Neq><Eq><FieldRef Name="_ModerationStatus" /><Value Type="ModStat">0</Value></Eq><Geq><FieldRef Name="Created" /><Value Type="DateTime">' + fromDate + '</Value></Geq><Leq><FieldRef Name="Created" /><Value Type="DateTime">' + toDate + '</Value></Leq></And></And></Where><OrderBy><FieldRef Name="_ModerationStatus" Ascending="True" /></OrderBy></Query></View>');


How do I to copy files to flash drive in a recovery mode?

It seems like to deleted too much files by rm -r and now I have the error of "the system is running a low-graphic mode" in Ubuntu and I have to work in Windows because of that.  However I can load it in recovery mode. I need to copy the files from Downloads folder to a flash drive. Downloads folder has them as I can see by ls command.   When I plug in a flash drive, there will be some messages saying that everything is ok (as I understood) and it's plugged. But when I go to /media/my_name and do ls then I don't see anything. I don't see anything in /run/media/my_name either(I'm not sure if should though).  I can't connect to the Internet for some reason. Ubuntu was installed by wubi.exe file.  How do I save the content of my Downloads folder to a flash drive?


How to delete specific lines from a txt file

I have a Bash script that writes data into a log file, then from that I take out stuff I want using the sed command. That gives me a file data.txt. What I want to know is how I go about deleting specific line inside that data.txt file.  For example:  123 456 789   I want to remove the 2nd line, containing 456 so that I only have  123  789   I tried with sed '2d' data.txt but it doesn't work.  I use this command to create data.txt from log.log:  sed -nE '1s/.{1}(.{2}).*/\1/p;' log.log >> data.txt


When did Death Eaters learn Voldemort was Tom Riddle?

In Goblet of Fire, Voldemort tells the Death Eaters at the Little Hangleton graveyard how he needed his father's bone to regenerate. The fourth and sixth books imply that Little Hangleton is definitely a small, primarily Muggle community. The Death Eaters would have been able to reason out Voldemort's likely blood status from this information alone, if they wished. They could also easily have glanced at the gravestone Harry had been bound to and seen the name of Voldemort's father -- "Riddle" -- and, being mostly interrelated purebloods themselves, they would know that there was no pureblood Riddle family in Britain.  And more to the point, he outright tells the Death Eaters his father is a muggle.     "You think I was going to use my filthy Muggle father's name forever?   I, in whose veins runs the blood of Salazar Slytherin himself, through   my mother's side? I, keep the name of a foul, common Muggle, who   abandoned me even before I was born, just because he found out his   wife was a witch? No, Harry - I fashioned myself a new name, a name I   knew wizards everywhere would one day fear to speak, when I had become   the greatest sorcerer in the world!"   None of them seem surprised to hear this, so apparently they already knew.  Barty Crouch Jr. already knew Voldemort was Tom Riddle Jr. and could easily have learned that Tom Riddle Sr. was a muggle. He alluded to this when he spoke to Harry.     The Dark Lord and I", said Moody, and he looked completely insane now,   towering over Harry, leering down at him, "have much in common. Both   of us, for instance, had very disappointing fathers... very   disappointing indeed. Both of us suffered the indignity, Harry, of   being named after those fathers. And both of us had the pleasure...   the very great pleasure... of killing our fathers to ensure the   continued rise of the Dark Order!".   When did the Death Eaters learn the leader of their pure-blood ideology was a half-blood? Did they learn back when Tom was a student at Hogwarts? During the First Wizarding War? Some other time?


Why didn't Fred and George discover Pettigrew first with the Marauders Map?

In Harry Potter and the Prisoner of Azkaban Fred & George give the Marauder’s Map to Harry. And then suddenly Harry discovers that Pettigrew is alive and in Hogwarts. But it is very strange that Fred or George never even discovered a Peter Pettigrew staying with their brother always. Was it mere misfortune or is there any other explanation?


Where to find structure of objects that I can access in PHP snippets added to different parts of UI?

In views I can add PHP snippets for custom validation or when I want to provide default value for contextual filter. It is telling me that I can use $view or $argument - but where is documentation of these objects? Where can I read what are my possibilities in these areas (or how check this, by using debugger for example)?


I am trying to make a if statement that check's if a input number is in the existing array.   What I trying to achieve is that I can insert a number in the input field and remove this one from the array. I am wondering what is the best way to do this.     var nummers = [20, 14, 39, 192, 39]; toon();  // button's maken document.getElementById("addOneBtn").onclick = addNum; document.getElementById("removeOneBtn").onclick = removeNum; document.getElementById("sorteerBtn").onclick = sorteer; document.getElementById("sorteer2Btn").onclick = sorteer2;  function addNum() {   var num = document.getElementById("addOneInput").value;   //nummers.push(" " + num);   nummers.push(parseInt(num));   toon(); }  function removeNum() {   if (document.getElementById("removeOneInput").value in nummers) {     nummers.pop();     toon();   } else {     document.getElementById("removeOneError").innerHTML = "not a number or in the array"   } }  function sorteer() {   nummers.sort(vergelijk);   toon(); }  function sorteer2() {   nummers.sort(vergelijk2);   toon(); }  function vergelijk(a, b) {   return a - b; }  function vergelijk2(a, b) {   return b - a; }   function toon() {   document.getElementById("arrayOutput").innerHTML = nummers.toString(); //renault.gegevens() }

 <input type="input" id="addOneInput"> <button type="button" value="add one" id="addOneBtn">Add one number</button>

 <input type="input" value="" id="removeOneInput">

 <button type="button" value="remove one" id="removeOneBtn">Remove a number</button>

 <button type="button" value="sorteer" id="sorteerBtn">Sorteer</button> <button type="button" value="sorteer omgekeerd" id="sorteer2Btn">Sorteer andersom</button>


bad camera angle (or trackers?) with aerial footage

Got this drone footage to track of a big truck patio. Huge stuff. The drone is quarter-circling the warehouses, and I could get me 8 solid tracking points and the camera solved.  Set the floor with 3 trackers: ok. Set the origin tracker: ok. Set x and y axis: ok. Link empties to track: ok. Setup tracking scene: ok.   Alright, seems fine. I can see the trackers on the background image on my 3d viewport, they line up with the footage.  I can align the 3d model of the warehouses as well. but it won't keep aligned as I hit play.  Among other things, I tried, so far:  Rotating the setup; Changing the height of the camera; Changing the scale; Manually correct the rotation on all axis; Setting the solve method to tripod; Scavenging an answer to a similar problem here on the forums: no success.  The thing is that the markers position is accurate only from the top view (wich is not the camera's position). Footage was not captured top down, so it doesn't make any sense to me that the markers are top down. I don't even know if I'm making myself clear. Hehe. But here's the weird alignment on the trackers to the camera:  It's flat, almost. And it really doesn't look like the angle the drone was relative to the ground.  What am I doing wrong? What is being missed? The parallax exist, doesn't it? Is there another approach to this? I tried the plane tracking, but in my research I figured that it wasn't the proper scenario for it.  Looking at the trackers spreading like that it makes me think that this is all incorrect, but then how one can track such a camera movement from aerial footage? We do have other takes from the same place, different views, but same alignment problem. The trackers kinda look flat.


Need regular expression that matches url

Below is my regular expression that matches url in a text which contains regular text, url and email ids. Problem here is,it also picks up the domain part from email ids.   /(?:(?=[\s`!()\[\]{};:'".,<>?"'])|\b)((?:[a-z][\w-]+:(?:\/{1,3}|[a-z0-9%])|www\d{0,3}[.]|[a-z0-9\-]+[.][a-z]{1,4}\/|[a-z0-9\-]+[.](?:[a-zA-Z]{2,4}))(?:[^\s()<>]+|\(([^\s()<>]+|(\([^\s()<>]+\)))*\))*(?:\(([^\s()<>]+|(\([^\s()<>]+\)))*\)|[^\s`!()\[\]{};:'".,<>?"']|\b))/   Here is the text  Is there a way to filter out the entire email id  My text     Neque porro quisquam est qui dolorem ipsum quia dolor sit amet,   consectetur, adipisci vel  eque porro quisquam est qui dolorem ipsum quia dolor sit amet xyz@abc.com   Matches     , abc.com   It should not match abc.com in xyz@abc.com


Possible for left hand infinite limit with right hand 0

Is it possible for a function to have a limit from the left be infinite and the limit from the right be zero if both limits are approaching the same number? I am inclined to say yes, but I am not sure, and is there an equation I could use to demonstrate this?


I can not edit a question when there is an uncompleted edit in the queue

When I wish to edit  (to add some additional tags) then I am missing the 'edit tags' button like I normally have. When I press the 'edit' button then I do not go the the edit dialogue but to a screen where I have to approve a pending edit.    The question looks like this:   no edit-tags button  and there is a marking '(1)' next to the edit button (probably referring to the review queue)     When I press the edit button then I end up with a screen for approving the edit. But I can not continue make edits to the tags.      I consider this as a bug.   Or possibly it is made by design (to prevent errors with merging multiple edits), but it is not very useful.   If people have enough reputation points to edit questions, then why should they wait for others to approve an edit made by another person?   Does this have to do with the scoring system that approving edits is also giving points to the person that made the edit?    Based on the answer from Glorfindel I notice that it is made like this by design. People can edit questions with an uncompleted question by improving the edit. However, they must not have already have approved or rejected the edit. Then this "bug"-report would be turned into a feature request asking for the possibility to still add improvements to the edit, after already having voted on the question.


Mount disk image for all users, even guest

What is the correct way to mount a disk image so all users (guest included) are able to access it?  I'm currently stuck after mounting it with:  sudo mount -o loop,users,ro,offset=262145048576 '/path/Disk Image.img' '/media/guest-Folder/Disk'   My normal user session can access it, but on a guest session I get an error: "This location could not be displayed. You don't have the permissions necessary to view the contents of Disk" while trying to view the contents in Nautilus.


Deleting emails from a sender after x days?

I have a web application that sends me many emails that are only for notification purposes - and so, are not important. There can be a great deal of these per day, and I sometimes forget to delete them.    I am using a Microsoft Exchange mail server, and do not have administrator rights to it. Is there a way I can set up/configure from Outlook a procedure that deletes emails from a specific sender after an amount of time?


String name; String count; Scanner keyboardn = new Scanner(System.in); Scanner keyboard = new Scanner(System.in); System.out.println("Enter Full Product Name"); name = keyboard.nextLine(); count = keyboard.nextLine(); String [] p = name.split(" "); for(String s : p) {      if (count == "1"){  System.out.println(p[0]);}     if (count == "2"){  System.out.println(p[1]);}     if (count == "3"){System.out.println(p[1]);}     if (count == "4"){System.out.println(p[1]);}     if (count == "5"){System.out.println(p[1]);}     if (count == "6"){System.out.println(p[1]);}     if (count == "7"){System.out.println(p[1]);}     if (count == "8"){System.out.println(p[1]);}     if (count == "9"){System.out.println(p[1]);}     if (count == "10"){System.out.println(p[0]+", "+p[1]+", "+ p[2]+", "+p[3]+", "+p[4]+", "+p[5]+", "+p[6]+", "+p[7]+", "+p[8]+", "                 + ""+p[9]+", "+p[1]+p[2]+", "+p[1]+p[2]+p[4]+", "+p[1]+p[2]+p[4]+p[5]+", "  );     } }   the program is not out puting any response using if statments i thought would work the best let me know if there are any other sugestions


I'm running Ubuntu 16.04 with GNOME 3 on my laptop. I use my laptop for university work, so often times I find myself using the search function of Gnome to get to certain class folders quickly. I've run into the issue where I get "No Results" when searching for a folder I know exists and have searched for many times.   I went to Settings and found the Search tab. There is an option to check on/off the different results you want to show up, "Files" being one of them. Within the Files option, you can add what folders you want to show up specifically. Even after I put the folders I want in, the search bar continues to come up with no results.  I have "Files" selected:   I specifically want to search for my "scripts" directory, so I add it to the search locations:   I type in "scripts" and it doesn't show up:   What can I do here? Is there a simple fix I'm just missing?


Autoconvert site-internal-link-only answers to comments

When an answer consisting solely of a link to elsewhere in the Stack Exchange universe is posted, it should be converted to a comment prefixed with "See: ".  Perhaps this could be widened to cover any single-link answer.  Some sort of rubric, perhaps     Your answer consists solely of a   hyperlink, and will be posted as a   comment unless you add further   details.   could appear when the answer is being composed.


I have a little problem with Java string.replaceAll function with regex.   The string is like:  String s = "${start}textcontent${end}something else${start}textcontent${end}"   Now I try to use replaceall.   s.replaceAll("\\$\\{start\\}.*content.*\\$\\{end\\}", "Bla");   The result I expect is  Blasomething elseBla   But result I get is just   Bla


It bothers me a lot when I'm spending some time and effort trying to answer a question only to learn it got closed for any reason. It's just a lot of time wasted. So I have come up with a solution for it:  Create a new button on questions called "Working on it". The user is guaranteed 30 minutes to answer the question, even after it is closed.  This way, I think it is a greater motivation too to answer questions without the fear of having all my work wasted.


I recently installed Debian from a live 7.5-amd64 image (downloaded from Debian's site) to a new laptop.  I also apt-get install'ed a few additional Debian packages.  I would like to clone this installation in another machine.  I imagine that one way to do this, when the second machine has the same hardware, would be to create an image of it, burn it to DVD, and directly copy it to the new machine's hard drive.  This is just a guess; I would have to do a lot more research to fill in the details.  But, more importantly, this technique may break down if the hardware of the target machine differs significantly from that of the original machine.  Is there some some way to get a description of the current installation that I could "play back" at the time of installing Debian on a new system?  (This description would have to include the choices made during the initial installation, as well as all the additional packages that were installed subsequently.)  If not, is there at least a way to get a listing of all the packages installed after the initial Debian installation from the live image?


How do I change a file title?   Nautilus properties dialogue only allows me to rename the file name, not the title.


Undefined control sequence, title, math and newcommand

Deal all,  I have the following couple of new commands, using amsmath and relsize packages :  \newcommand*{\chiffraged}[2]{$\genfrac{}{}{0pt}{}{\mathlarger{#1}}{\mathlarger{#2}}$} \newcommand*{\sixcinqbarre}{\chiffraged{6}{\cancel{5}}}   which allow me to display, in a regular text, a musical chord notation like this (chord C) :    When I use my \sixcinqbarre in my text, no problem, everyting works (example in french, sorry):       On trouvera tout naturellement l'écriture \textit{do ré}\quartesixte~\textit{mi}6 précédée du \textit{si}\sixcinqbarre .      L'accord de passage est en général faible tandis que les deux accords de tonique sont     placés sur les temps forts.     L'accord sur la sensible est ainsi lui aussi en position faible. On a     donc \textit{si do ré mi}. Nous en donnons un exemple.   gives:    When I use it in a title with no toc reference, like \subsection*{\sixcinqbarre}, idem, no problem. But when I use it in a regular title, like this \subsection{\sixcinqbarre}, I have the following error :  ! Undefined control sequence. \rs@makelargerchoice ...displaystyle \rs@mathatom \m@th $}}{\displaystyle \l... l.197 ...\sixcinqbarre ~avec la basse descendante} The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined.   Does anyone have a clue about this?  Edit: After some tests, it seems that the use of the hyperref package is the cause of the error. Here is a code to test:  \documentclass[a4paper]{book} \usepackage[]{hyperref} \usepackage{cancel} \usepackage{amsmath} \usepackage{relsize}  \DeclareRobustCommand*{\chiffraged}[2]{$\protect\genfrac{}{}{0pt}{}{\protect\mathlarger{#1}}{\protect\mathlarger{#2}}$} \DeclareRobustCommand*{\sixcinqbarre}{\chiffraged{6}{\cancel{5}}}  \begin{document} \section{\sixcinqbarre} \end{document}   Comment the \usepackage[]{hyperref}, and it works! However I would like to keep it...any idea?


System Load Indicator only shows as a line unless hovered

I installed the  GNOME extension on my Ubuntu 18.04, but for some reason, instead of showing a proper graph for CPU usage, it only shows a very thin line that seems to be a small portion of the actual graph. If I hover over it, the proper graph shows. How to make it show the whole graph all the time?


Which form of this sentence is correct. "No one works as hard as him." Or should it be, "No one works hard as he."?


I have seen the Unsung Hero gold badge which is awarded on 10 accepted answers with total scores of zero.  My 10 answers have been accepted with score of 0. I have answered a total of 107 questions on which 13 are answers with 0 score. Out of these 13, 3 are answers to my own questions after research, but there are 10 questions which are accepted by other users.   I have still not been awarded the Unsung Hero gold badge. What is the reason?


What do you call a person who collects branded things?

What do we call person who buys or collects branded things like shirts, shoes, cars etc...


How do I get a random number with a negative number in range?

Consider the following code: int rand = new Random().nextInt((30 - 20) + 1) + 20  It will return a random number between 30 and 20. However, I need its range to include negative numbers. How would I include negative numbers in the generation? I have tried using math that would be negative, but that resulted in an error. Simply subtracting or adding the negative numbers would not yield the desired value.  Sorry, I am only half awake. The correct code is int rand = new Random().nextInt((30 - 20) + 1) + 20;.


Connectedness of the One-Point Compactification

This was a bonus question on a recent homework in my point-set topology class. I've since turned in the assignment but still don't have an answer to this question.     Let $X$ be a locally compact Hausdorff topological space. Let $X^+$ denote the one-point compactification of $X$. Prove or find a counterexample to the following claim: If $X^+$ is connected, then $X$ has no connected components which are compact.   The converse is true and straightforward to show. If we add the assumption that $X$ is locally connected, then the statement is true. And if we remove the requirement of local compactness, then it's false. But in its current form I haven't been able to make heads or tails of it.


How to install Win 8.1 to HDD as booting it from SSD?

I try to install Win 8.1 to my new computer with both SSD and HDD. I want to boot it from SSD but keep the all related files in HDD. Is it possible to choose such a scheme for the installation ?  If you know Linux, then what I want is pretty similar to create /boot partition at SSD and keep all /root /home partitions at HDD. However, in the installation process of Win 8.1, I cannot see any advance partition tool to define such detail schema.


I tried to do install yandex browser. Something went wrong and now i get this message:  N: Ignoring file 'yandex-browser.list.save.1' in directory '/etc/apt/sources.list.d/' as it has an invalid filename extension N: Ignoring file 'yandex-browser.list.save.2' in directory '/etc/apt/sources.list.d/' as it has an invalid filename extension E: Type 'andex.ru/yandex-browser/deb' is not known on line 1 in source list /etc/apt/sources.list.d/yandex-browser.list E: The list of sources could not be read. N: Ignoring file 'yandex-browser.list.save.1' in directory '/etc/apt/sources.list.d/' as it has an invalid filename extension N: Ignoring file 'yandex-browser.list.save.2' in directory '/etc/apt/sources.list.d/' as it has an invalid filename extension E: Type 'andex.ru/yandex-browser/deb' is not known on line 1 in source list /etc/apt/sources.list.d/yandex-browser.list E: The list of sources could not be read.   Can somebody help me? Im new to linux.When i tried to remove file from directory,it said i dont have permission to do that,i think. Thanks


Why do we say that elementary particles are pointlike?

When people discuss quantum field theory in a popular context, they say that fundamental particles, such as quarks and electrons, are pointlike, with zero size.  However, I don't think this is what QFT says at all. My impression is that a particle is an excitation of the field, and hence a wavepacket with finite size. Of course, you can have a spike in field value at a single point, like $|x \rangle$ in quantum mechanics, but this state is pathological, and it's definitely not what we mean when we say 'particle'.  Interactions between fields are local and hence only happen at a single point. But to calculate the result of a scattering, you have to integrate this over the positions where the incoming wavepackets overlap. So it doesn't make sense to say that interactions occur at a point either.  If field excitations are not pointlike, and interactions of fields don't occur at points, then what do people mean when they say particles are pointlike?   Edit: I don't think  answers mine. The top voted answer just reiterates that the Lagrangian is local, but most of the time people seem to be making the much stronger statement that particles are perfectly localized. As argued above, these are not the same thing. I'm wondering if there's any justification for the latter, or if it actually doesn't make sense.


Questions voluntarily deleted by their authors, who later delete their accounts show to <10k users as "removed for reasons for moderation"

was voluntarily removed by its author. The author then deleted their account.  Generally, when the author deletes their own question, the "not found" error message shown to <10k users says:     This question was voluntarily removed by its author.   However, if the author deletes their own account sometime after deleting their own post, the notice changes to:     This question was removed from [site name] for reasons of moderation. Please see the help center for possible reasons why a question may be removed.   ...which is shown on questions deleted for any reason other than by their author.  Screenshot:        I believe this is incorrect; it should continue to show the former error page on voluntarily deleted questions even after the author's account gets deleted.


Explain why $E(|X|^p)=p\int_{0}^{\infty}y^{p-1}P(|X|>y) dy$

I'm trying to understand a passage from the book: A Basic Course in Probability Theory, Rabi Bhattacharya Edward C. Waymire, in the page 21. The calculation is the following:  If $X$ is a random variable on $(\Omega,\mathcal{ F}, \mathbb{P} )$, then for any $p > 0, x ≥ 0$, writing $x^p=p\int_0^x y^{p−1} dy$ in the formula $\mathbb{E}|X|^p = \int_Ω |X(\omega)|^p \mathbb{P} (d\omega)$ we  obtains:  $$ \mathbb{E}|X|^p=\int_{\Omega}\left(p\int_0^{|X(\omega)|}y^{p-1}dy   \right)d \mathbb{P} ~~ {\color{red}=^{??}}~ p\int_{0}^{\infty}y^{p-1}\mathbb{P}(|X|>y) dy $$ I do not understand how the left side of the above equation became the right hand side. I know that the Fubini's theorem should be used but do not know the complete details.


Deploying Profiles from one sandbox to another sandbox using ANT Tool or any other tools

I have 5 profiles in my test sandbox. Now i am planning to move these profiles to another sandbox. What is the best tool to deploy these profile. I seen lot of people don't deploy profiles using deployment process, they do it in post deployments.  If i do in post deployment it will take lot of time to configure manually everything. Please suggest me the safe way to deploy the profiles!!  Thanks in Advance


What is the prefered method for creating a byte array from an input stream?   Here is my current solution with .NET 3.5.   Stream s; byte[] b;  using (BinaryReader br = new BinaryReader(s)) {     b = br.ReadBytes((int)s.Length); }   Is it still a better idea to read and write chunks of the stream?


I am trying to use a php variable in my javascript code, but i cant seem to get it working. Here is my js and php code:  <?php $s = "woo"; ?> var images = <?=$s?>;   What i want to achieve, is a php variable in javascript ENCLOSED with ['']; With other words, so that the javascript code reads it like this: ['woo']; I could really need some help, as i am very new to javascript. Thanks in advance.


I'm pretty sure I couldn't earn 200 rep recently, moreover I'm an inactive user for years, just occasionally returning here to have a look


What happens if a user uses a copyright image as a profile image on SO or any other site?  Is it ok to use such images because according to law it is illegal to use anything which has a copyright?  My question is just related with User Profiles on SO not other social media sites.  If a copyright issue is occurred then who is responsible for it?


I just installed the latest version of Ubuntu next to my Windows 7 system. After I restarted my computer, it started Windows 7. I looked under Computer if I can start Ubuntu under Windows 7, but it does not show me the partition where I installed Ubuntu with 3 partitions. I restarted again, went to boot menu, but wasn't able to start Ubuntu. What can I do?


Unable to use Stack Overflow chat despite having enough reputation

I have 24 reputation points, but SO chat is still giving me the message "you must have 20 reputation...." Why can't I join the chat?


let $a,b,c$ be postive real numbers ,and such $$ab+bc+ac=3$$   show that   $$\dfrac{a^2}{a+2b^2}+\dfrac{b^2}{b+2c^2}+\dfrac{c^2}{c+2a^2}\ge 1$$   This problem is from Secrets In Inequalities volume 1  page 30,example 1.24. the comment.the  author this case is a bit more diffcult,But this author can't post solution.Thank you


I've got a new notebook with freeDOS as only OS

I've got a new Asus x550V notebook without OS preinstalled. The only thing on this laptop is FreeDos. For some reason Installation though USB stick does not working.   I followed all of the steps I found to try and get the usb drive to boot. I've change my Bios boot option priority to USB and it still does not give me the option to install though USB.   I can only enter Freedos. So I burned a DVD with a downloaded .ISO file from ubuntu. I changed my boot options to give the DVD ROM priority but it still does not want to install ubuntu. I always end up booting FreeDos.   Do I need some kind of command to start booting linux? I am sorry for my english, I am kinda frustrated.


In a math textbook I found a statement that every empty set is equal. There are such sets that it is impossible for them not to be empty:  set of all natural numbers between 10 and 11. There are such sets that it is possible for them not to be empty:  all the people from the Earth, who are on the Mars now. In future it can be possible. Quesstion: can sets mentioned in 2 be equal to sets mentioned in 3. If yes, why not to take in account the difference examples above?


Install Numpy for Python3.4.0 on Ubuntu 14.04.01 LTS

Python3.4.0  on Ubuntu 14.04.01 LTS. We can use it by typing on Terminal `python3.  I want to use Numpy for Python3.4.0. I run import numpy  but I had anImportError.So sudo apt-get install python-numpy. Then I typed on Terminal:python3`. Then import numpy. I got this error:  >>> import numpy Traceback (most recent call last):   File "<stdin>", line 1, in <module> ImportError: No module named 'numpy' >>>    Nevertheless, Numpy is now working for Python-2.7:  begueradj@begueradj-Bill:~$ python Python 2.7.6 (default, Mar 22 2014, 22:59:38)  [GCC 4.8.2] on linux2 Type "help", "copyright", "credits" or "license" for more information. >>> import numpy >>>    How can I make Numpy work for Python 3.4.0 ?


I wanted a Django model with 2 foreign keys from the same table.  It's an event table which has 2 columns for employees: the 'actor' and the 'receiver'. But I get this error:      Error: One or more models did not validate: tasks.task: Intermediary   model TaskEvent has more than one foreign key to Employee, which is   ambiguous and is not permitted.   Is there a better way to model this? Thanks  I think I'm going to add a TaskEvent_to_Employee table.  There will be two records in it, one for each of the two employees related to each TaskEvent.  Anyone know an easier workaround?


Reset keyboard shortcut for changing language

I upgraded to 21.04, then a message appear to set shortcut for changing languages (RO - EN). For some reason I set Left Shift + Left Ctrl. Now I realized I can't open a new tab in terminal anymore (with Ctrl + Shift + T) because the language is changing instead. I opened the Region & Language settings, then Input Sources: Keyboard Shortcuts. Here the message is: These keyboard shortcuts can be changed in the keyboard settings. Ok, I opened the Keyboard Shortcuts and I have Typing: Switch to next input source: Super + Space. But I can't see the Ctrl + Shift shortcut I want to remove. So, where can I fix this?


There is a new trend on some Universities (in engineering and science majors), that professors show lecture slides over a video projector on the screen instead of writing on the chalkboard. They enter the hall, stay two hours totally passive before the students and read the slides aloud without explaining it. I even have had a mathematics course, in which the professor read the slides like a textbook without explaining them on the board or working examples.   Are you also affected? Which method do you think is more effective? What are the advantages and disadvantages of each? (I myself believe the chalkboard is much more effective.)


Are contributions to conference proceedings considered to be "archival" publications?

While technical papers are generally considered to be "non-archival" and journal papers "archival", I couldn't find a clear statement about papers that appear in conference proceedings. Does it matter in which for the proceedings are published, e.g. only online, on CD/USB drive, or printed with/without ISBN?


Word for a male that prefers female companions (no slang such as "pimp")

I am looking for a word describing a man who has a lot of female friends, and who prefers female friends.   I was "Wikipedia surfing" (going through Wikipedia pages and clicking on links found within the wiki), and I came upon the page of a man who had a lot of female friends, and there was a word that described that attribute succinctly.   I do not remember any details about the bloke. I looked up the word (I seemingly immediately forgot it), and, to tell the truth, I am unsure whether the word defined "someone who has a lot of friends of the opposite sex" (which, if true, means in my memory I incorrectly paired the word's definition to his gender), or more specifically, "a man who has a lot of female friends (and/or) prefers female companionship", where companionship does not insinuate sexual relationships.  If there were two words for the two definitions I just gave that'd be all the better! I have tried to remember for quite a while to no success.    An update: perhaps an example for some clarification is necessary. Imagine a scenario where you have a gay man (who has never had sexual interests in women) who has all female friends, who know he is gay, and no male friends. Here he prefers the companionship of women, and not of men; thus, he could be a "ladies' man", but only speciously, since I believe the word implies some yearning, from either the women or the "ladies' man", to copulate, which doesn't exist here. The word would also apply for a lesbian who only has male friends (who she has no desire to copulate with), and who thus prefers them as companions. So, generally, we'd get: "someone who prefers the company of members of the opposite sex". I hope this clarifies the request some. Thank you.


wc -c not working in a loop in the script

So I'm writing a simple script that checks if the size of the file is less than the given argument and if its true then its suppose to echo "YES"  #!bin/bash  Function () {     cd $1     lista=`ls`     for item in $lista     do         if [ ! -d $item ]         then             size=`wc -c $item | awk '{ print $1 }'`             if [ $size -lt $2 ]             then                 echo "$item"             fi         else             Function $item $2         fi         cd ..     done }  Function $1 $2   And the bash:  bash test2.sh /home/161161 300   However something is wrong with the wc -c because it gives me the error that no such file or exist after running through the second loop.  Any ideas?


Help a DND noob out? Proficiency and how it is used?

I am extremely new to D&D and I'm filling out a 5th edition character sheet for the first time. I chose my race as elf and it says, "You have proficiency in the Perception skill." What's proficiency? How do I fill it out, what do I write? And also how would it be used in combat..?  Just explain it to me as if I am five years old. A scenario would be nice.. Sorry for the trouble, first time with RPG games as well


Understanding of "inline" in C++ class constructor?

I read a source code of class address_v4 in boost library and there are several constructors declared with BOOST_ASIO_DECL (defined as inline)  /// Construct an address from raw bytes. BOOST_ASIO_DECL explicit address_v4(const bytes_type& bytes);  /// Construct an address from a unsigned long in host byte order. BOOST_ASIO_DECL explicit address_v4(unsigned long addr);   (from here )  # define BOOST_ASIO_DECL inline   (from here )  So, what the purpose of specifing "inline" for c++ constructor ? Is it the same meaning as for functions or it has a different meaning ?


Difference between speed of light and of bullet after passing through a barrier

I just read that, when a ray of light traveling in vacuum at $c$ strikes a glass slab, its speed decreases and then when it re-emerges it gets back to its original speed i.e $c$.  If I draw a comparison with a bullet fired at a metal sheet, then when it re-emerges its speed is drastically reduced.   So, why hasn't the same principle been applied in both the situations? Doesn't the first case violate any energy principle?


How to find which edition the SQL Server installation media belongs to

Without installing SQL Server media 2008 and 2012, how can we know that the media belongs to a certain edition (like Developer, Standard or Enterprise)?


Intuitive description of what a topological space is?!

I have read several texts that give a very technical description of what a topological space is, but I can't find any notes that really give an intuitive description of what it is and I'm really struggling to get my head around it. Is the idea behind a topology the notion that we wish to be able to have a notion of "nearness" of elements to one another in a set, without introducing a notion of "distance"? By "nearness" is it meant that two elements are within the same neighbourhood (i.e. they lie within the same open subset)? Given this, is the idea that two objects are topologically equivalent, e.g. a coffee cup and a doughnut, that the neighbourhoods that elements "reside" in are unaffected under a continuous deformation from one object to the other, such that "nearby" elements remain "nearby" (relative to one another)?  I would really appreciate it if someone is able to give me an intuitive notion of a topological space, and also a motivation for such a concept. Thanks.


Copy the property values to another object with C#

To copy the property values from one object to another, we usually achieve with following syntax:  ca.pro1 = cb.pro2; ca.pro2 = cb.pro2;   where ca and cb are of the same class.   Is there any simpler synatx or utility method to help us to achieve the same effect?  Thank you.


Drupal 7 drupal_add_tabledrag dragging but not dropping

I am trying to use the drupal_add_tabledrag in a form table, the dragging is added fine, but dropping is not working  $entity_ids = range(10,20); // Loading dummy data  $entities = entity_load('node', $entity_ids); $rows = array();  foreach ($entities as $id => $entity) {     $rows[$id] = array(         'data' => array($entity->title),     'class' => array('draggable', 'entity-weight'),     ); }  $form['settings']['entities'] = array(     '#tree' => TRUE,     '#theme' => 'table',     '#header' => array(t('Title')),     '#rows' => $rows,     '#attributes' => array('id' => 'entity_table') );  $form['settings']['title'] = array(     '#type' => 'textfield',     '#title' => t('Find entity'),     '#autocomplete_path' => 'list_bean/autocomplete', );  drupal_add_tabledrag('entity_table', 'order', 'self', 'entity-weight');  return $form;   I can rearrange items using drag, but I cannot drop the item I drag, it sticks tot he cursor.


I am trying to multiply decimal value with 10 in Javascript:  console.log(1000.56 * 10); console.log(100.56 * 10);   It is printing.  10005.59999999999 1005.6   Why?


How do I get the latest GIMP version available?

I understand that there is a new version of the GIMP available, although it appears that the only way of doing this is by compiling from source :P  Is there another way of getting it, or if I have to compile can I do that through the terminal or better still; a GUI?


I want to install Ubuntu 14.04 on my laptop and it has amd e2 vision  processor  I don't know know if my machine is 64-bit or 32-bit so I am having confusion downloading the UBUNTU version (64 or 32 bit)  Can anybody help??


I'm doing a project, but when I decided to do an animation this happened! I don't know what to do. you can see through  the screenplay of the problem. I need help!


I have a HTML report, which needs to be printed landscape because of the many columns. It there a way to do this, without the user having to change the document settings?  And what are the options amongst browsers.


I read information , and in other places. But I can't come up with the perfect example that move away my doubt.  I found this in  which help me a little bit. But no really entirely.  so as to do something  In order to do something: She had put her hair up so as to look older.  So, if I understood well, I think that I can use so as for get accomplish something. Right?  I mean, Can I ,literally, replace so as by in order?


Why does System Properties display two different frequencies?

My System Properties window has the below text (also see screenshot). What does the "1.20 GHz " refer to?     Hewlett-PackardHP Compaq dc7700p   ConvertibleIntel(R) Core(TM)2 Duo CPU   E4400 @ 2.00GHz   1.20 GHz 3.50 GB of RAMPhysical Address Extension


I installed applications such as : Stacer,Latte,Sweeper,ONLYOFFICE,easyTAG,Files,etc. through software center Discover. I noticed that some of them are not updated to the latest stable version. My question is if these applications will update automatically ? (or i will have to uninstall them and install again with the latest version)


I've heard "from whence it came" said many times, often when the writer is attempting to be formal (or is in fact formal). But the  of whence is "from what place, source, or cause" (with "from" being the key word). So is it wrong to say "from whence it came"?


Can a spaceship increase velocity "infinitly"

This keeps me awake at night, and i can't seem to find the solution.  Introduction: Suppose an observer is currently at rest, and a space ship accelerates close to the speed of light (current velocity of spaceship from observers point of view = 0.99c). The observer can now see that the spaceship travels close to the speed of light, however, the spaceship still see light passing the spaceship with the speed of light.  Now the question is: Due to the fact that the spaceship still see light passing at "c", does that mean that the spaceship would be able to increase its velocity close to what the spaceship now perceive to be the speed of light? And would the observer only see that as a small increase in velocity (current velocity of spaceship from observers point of view = 0.9999c) of the spaceship?


How can I implode this array into a url string

I have an array like this:  $aSample = [    'productName' => [         'sample',         'sample2'     ],     'productNumber' => [         'numberOne',         'numberTwo'     ] ];   How can I make this array look like this one:  productName=sample,sample2&productNumber=numberOne,numberTwo   Thank you for the help in advance!


I have $f:\mathbb{R}\rightarrow \mathbb{R}, f(x)=\sin(4x)+\cos(x\sqrt{2})$ and I need to find the period of this function. I found that the period of $\sin(4x)=\pi/2$ and the period of $\cos(x\sqrt{2})=\pi\sqrt{2}$. Why doesn't this function have a period and how can I  approach the exercise?


Can I award user with special bounty after accepting his anwer?

I have a , and I haven't start a bounty for this question. After I got my answer I'd like to give a user a special bounty, because I consider his answer very helpful and it saved me a lot of time. I've already accepted the answer. Is there a way how can I give him some bounty?  Thank you


How to avoid shift of position of nodes when new children are added in slides using tikzpicture with beamer? (MWE available)

The whole diagram shifts up when more children are added in the second level. Is there a nice way to adjust this automatically, so that the top nodes do not change their position from one slide to the next? For example, see slide 1 and 2 in the following code: (Thanks in advance) \documentclass{beamer} \mode<presentation>{\usetheme{Madrid}}   \usepackage[style=verbose]{biblatex} \usepackage{tikz} \usetikzlibrary{shapes.geometric, arrows} %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% \tikzset{startstop/.style = {rectangle, rounded corners, minimum width=3cm, minimum height=1cm,text centered, draw=black, fill=red!30}} \tikzset{io/.style = {trapezium, trapezium left angle=70, trapezium right angle=110, minimum width=3cm, minimum height=1cm, text centered, draw=black, fill=blue!30}} \tikzset{process/.style = {rectangle, minimum width=3cm, minimum height=1cm, text centered, text width=3cm, draw=black, fill=orange!30}} \tikzset{decision/.style = {diamond, minimum width=3cm, minimum height=1cm, text centered, draw=black, fill=green!30}} \tikzset{arrow/.style = {thick,->,>=stealth}} %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% \title[tikzpicture with beamer]{}  \begin{document} \begin{frame}{tikzpicture}{} \begin{tikzpicture}[node distance=3cm]  \node (root) [process] {root}; \node (child1) [process, below of=root, xshift=-4cm] {child1}; \draw [arrow] (root.south) -- (child1.north);  \node (child2) [process, below of=root, xshift=0cm] {child2}; \draw [arrow] (root.south) -- (child2.north);   \node (child3) [process, below of=root, xshift=4cm] {child3}; \draw [arrow] (root.south) -- (child3.north);  \node<+(1)-> (child21) [process, below of=child2, xshift=-3cm] {child21}; \draw<.(1)-> [arrow] (child2.south) -- (child21.north);  \node<+(0)-> (child22) [process, below of=child2, xshift=3cm] {child22}; \draw<.(0)-> [arrow] (child2.south) -- (child22.north);  \end{tikzpicture}     \end{frame}  \end{document}


Why was Frodo able to go to the Blessed Realm?

All along, I had the impression that, as reward for resisting the One Ring and contributing towards the journey to its ultimate demise, Bilbo (for finally abandoning it), Frodo (for having done the most to carry the burden for the actual journey) and Sam (for carrying it when Frodo couldn't and successfully resisting temptation to take over as the main bearer) were granted passage to spend the remainder of their mortal days in the Undying Lands, where the Blessed Realm can help heal/protect their souls from the dark taint of the Ring until the end of their days.  I just found Arwen's wiki article, though, and a passage quotes thus:     After marrying Aragorn, she bestowed upon Frodo Baggins a gift: Her place on the ships to Valinor.   This implies that Frodo was originally ineligible for entry into the Undying Lands, until Arwen gave him her ticket.  Is my prior impression wrong? I think it came from many years ago, the one time I read RotK. If I am correct, then why does the quoted passage seem to conflict it? Did I misinterpret it, or is it a movie vs book thing? If I am wrong and the quoted passage is correct, then:   Why can Bilbo and Sam go to the Undying Lands? Whose place on the ships did they take? Arwen already gave up her immortality to be with Aragorn. She is known to have told her father Elrond: "There is now no ship that would bear me hence". I don't think the choice of abandoning immortality can be walked back once made, so why did she have a seat to offer to anyone by that point? Even if she still held a place on the ships to the West, is it her place to offer it to anyone?


Forcing subfigures to have same height and take overall X% of linewidth in LaTeX

I want to make a figure composed of two images that have different sizes. I want to put them side by side so that they have the same height and that they overall take, say, 90% of the line width.  It is easy to make them have the same fixed height (say in cm), but how to let this common height be automatically adjusted to fulfill the desired overall width? Manual trial-and-error is time-consuming, approximate and non robust.  A solution with or without subfigure or another LaTeX package is OK.


Declare a generic type instance dynamically

Is it possible to declare an instance of a generic without knowing the type at design-time?  Example:  Int i = 1; List<typeof(i)> list = new List<typeof(i)>();   where the type of i could be anything, instead of having to do:  List<int> list = new List<int();


How can I find the roots of $x^3-3x+1$ using Cardano's formula?  So far, I found that   $$x = \sqrt[3]{\dfrac{-1+\sqrt{-3}}{2}} + \sqrt[3]{\dfrac{-1-\sqrt{-3}}{2}}$$ $$x = \sqrt[3]{\dfrac{-1+i\sqrt{3}}{2}} + \sqrt[3]{\dfrac{-1-i\sqrt{3}}{2}}$$ $$x = \sqrt[3]{\frac{-1}{2}+\frac{i\sqrt{-3}}{2}} + \sqrt[3]{\frac{-1}{2}-\frac{i\sqrt{-3}}{2}}$$  I am now trying to express each cubic radicand in their exponential form.  Euler's formula : $e^{i\theta} = \cos \theta + i\sin \theta$.  I have $r = |z| = 1$.  However, when I try to find the angle, I get  $$\theta = \arccos \frac{-1}{2} = 2\pi/3$$  but at the same time  $$\theta = \arcsin \frac{\sqrt{-3}}{2} = \pi/3$$  Shouldn't the two angles be the same for one radicand?  Plus, once I will have expressed the two radicands in their exponential form, what is the next step?  $$x = \sqrt[3]{e^{i2\pi/3}} + \sqrt[3]{e^{i4\pi/3}}$$ $$x = e^{i2\pi/9} + e^{i4\pi/9}$$  Am I on the right track?


Word with the same meaning as "good moments" or "pleasant memories"?

Is there a single word with the same meaning as "good moments" or "pleasant memories"? I'm looking for a word which describes good thing(s) that happened to someone. The only word I can think of is "joy".  Some examples might be:   Wayne has many pleasant memories of the days spent with the family. She could remember many good moments from the last weekend.


why two decimals add together there are so many zeros in the result, just curious

I just run this in the console, and this is the result I get, I am just curious why it happened. 6.12+9.3 15.420000000000002


File in Use: The action can't be completed because the file is open in Windows Explorer

I checked my Windows Explorer and I don't see the file so I am wondering if there is a way to find a particular file or program that is stopping the deletion process from taking place.


The  came with a driver CD for Mac OS and windows but not ubuntu(linux). I recently switched from Windows to linux and  . I did as the instructions were given AND the printer seems to work, but scanning doesn't work. The error message says "USB can't connect" in the PC and "Can't connect to PC" in the scanner's LCD display. What should I do?  I would have contacted their support but their form keeps popping error messages and I can't even register, but I seriously need to use the scanner.


Why can I get a virus or trojan from visiting a website?

I have seen these a lot lately. You click the link, and instant trojan. No need to download or anything.   How is this possible? Is there a way I can scan the links before visiting to make sure I won't be infected?


Numberphile: Vi Hart's favourite number, $*$. What is it?

I apologise if this is a duplicate in any way. I couldn't find anything here.  In  Numberphile video at about six and a half minutes in, Vi Hart chooses the "number" $*$ as her favourite number. She says it's less than all the positive numbers and greater than all the negative numbers, but is not zero.     What is a formal definition of this "number" (if the above doesn't qualify as one)?   She says it's used in Combinatorial Game Theory. What is it used for exactly?


It looks like the spacing for the last modified tagline lost its right justification

This feels wrong in my brain, so I think it's a new change... If the tag list is short, the line showing last modification and the user+rep loses its right-justification (red), but if the tag list is long enough to cause a linewrap, it is properly right-justified (green).  This happens here on MSE as well as the main page of Physics.SE and Physics Meta. I suspect it is global, but I haven't looked at any other sites. This is Firefox 89.0 (64 bit) on Windows 10, and I haven't tried other browsers or OSes.


After a race, at least a Grand Prix race, you can hit x to star the race. What's unclear is what that does.


Calculating logarithm without calculator

I have a short question. How can I calculate a logarithm without a calculator?  For example:  Log base 8 of 4, log base 16 of 2.. Thanks.


What is the meaning of an autoregressive parameter greater than one?

I have created a AR(2,1,0) model with the first two parameters equal to -1.08 and -0.33. I understand that a autoregressive parameter equal to 1 implies non-stationarity and a random walk process so I'm assuming the effect is the same if the parameter is a -1. So what does it mean when the parameter is greater than one?  This model performs pretty well so I'm not sure if something is incorrect.


I'm following  and I've set my compositor up in the exact same way as he did, except my background is like a slightly light grey and I don't know why.  In his video's he's getting a bright white as his background and I can't see where I'm going wrong.  Here's the render:   Here's the compositor window:    file.  Please help! I really want to know why it's not happening.


Sum of all residues of $\frac{P(z)}{Q(z)}$ is zero

Let $P(z)$ and $Q(z)$ be two polynomials such that $deg(Q) ≥ 2 + deg(P)$. Suppose {$z_{1}, . . . , z_{n}$} is the set of all distinct poles of $\frac{P(z)}{Q(z)}$. Show that $\sum{Res(\frac{P(z)}{Q(z)}; z_{j})} = 0$. I know we can take a contour that contains all the poles and use $Res(\frac{P(z)}{Q(z)},\infty)=0$ to show the sum of Res above is zero. I just wonder if there is another to prove it?


Python: How can I know which package I am importing?

I would like to have this info during run-time or in ipython. For example,   import matplotlib   How do I know which matplotlib.py is used if I have multiple versions or I just want to know where the file located.  Thanks


Deleted .aae files and now the related photos are gone

I was manually copying my photos from my iPhone 6 running iOS 9.3.1 onto my Windows 8 laptop and deleted all the .aae files associated with the various JPEGs before copying them over. I immediately found that the JPEGs associated with the .aae files were rendered unmovable and inaccessible.  I understand that .aae files are used to keep a history of photo modifications so that one can revert if one wants in the future, but I didn't think they were integral to accessing my JPEGs as I've been able to delete them AFTER transferring them to my laptop before without issue.  So now, I have a load of great pics I can't transfer and can't access.  I also tried unplugging and replugging my iPhone to my laptop, but now the once-inaccessible JPEGs seem to have totally gone.


Find the general solution for this equation sin5θcos3θ = sin6θcos2θ.

I have tried to solve it but my is wrong. I did the following-  using $$2\cos b\sin a = \sin(a+b) + \sin (a-b)$$  $$2\sin5\theta\cos3\theta = 2\sin6\theta\cos2\theta$$  $$\sin 8\theta+ \sin 2\theta = \sin8\theta+\sin4\theta$$  $$\sin2\theta - \sin4\theta = 0$$  $$\sin2\theta - 2\sin2\theta\cos2\theta=0$$  Case $1-$ $$\sin2\theta=0$$  $$\sin2\theta=\sin0$$  $\therefore$ $\theta = \frac{m\pi}{2}$  Case $2-$  $$2\cos2\theta =1 $$ $$\cos2\theta=\frac{1}{2}$$  $\therefore$ $\theta = n\pi \pm \dfrac\pi{6}$  So where I did wrong ????


How to improve English quality of my paper?

I am in phase of writing 2nd paper. Previous paper is rejected. The one of the main objection in previous paper was English quality. As English is not my native language and reviewers only say "there are some mistakes, paper quality needs to be improved". This puts me doubt in myself and my major concern becomes writing instead of doing research. I spend a lot of time to read my paper again and again and re-write sentences. But how do I know that it is good now. It is infinite loop for me. What should I do to enhance quality of English. I have nobody available to review my paper for me. Kindly give me some suggestions:   What about online proofreading software i.e. grammarly, language tool, perfectit etc? which one do you use especially for scientific writing form computer science domain? What about online copy-editors and proofreaders that are available to read my paper. I have checked some websites but the charges were too high. Do you have used any service like this that had affordable cost any other options?


Order of multiplication and division, is there an official consensus?

Lately, equations such as X=8/2(2+2) have begun being presented on social networks as "very hard problems that will divide the audience just like the striped dress optical illusion". Of course, most of people coming at different results are blindly following the BODMAS or PEMDAS mnemonic incorrectly, saying that multiplication always goes before division or the opposite, where in reality most sources I've found say "multiplication and division" and "addition and subtraction" are single steps. I thought those were easy to disprove, but then someone stated that the "left to right" rule is only spelled out for sums and subtractions, and not for multiplication and division, and people writing expressions always needs to use parentheses or horizontal fracional bars to disambiguate an otherwise unknowable order, making 8/2*2=? Someone else said that implicit multiplications like 2(2+2) must be done first, and that 8/2*(2+2)=4*4=16 but 8/2(2+2)=8/2(4)=8/8=1. Is there a true consensus on what the correct order is?


Should I ever do "sudo apt-get dist-upgrade" on a mission critical server?

I'm pretty sure the answer is "no," but there's more to this question.  If dist-upgrade often downloads kernel upgrades, will my Ubuntu server always be stuck at a certain kernel if I always just do sudo apt-get upgrade? Or do I not really need the kernel upgrades? I assume I'll still receive security patches and other software updates?


How to prove $\lim \limits_{x \to 1^-} \sum\limits_{n=0}^\infty (-1)^nx^{n²} = \frac{1}{2} \ $?

$\lim \limits_{x \to 1^-} \displaystyle \sum_{n=0}^\infty (-1)^nx^{n²} = \frac{1}{2}$  The power $n^2$ is problematic. Can we bring this back to the study of usual power series?  I do not really have any idea for the moment.


Does a humming bird eating flower juice in an accelerating train, need to fly forward or just fly to remain at the same place?

Does it need to fly forward? Or just need to fly to keep at the same position as usual?


My book, in mechanics, claimed that the normal forces were actually a result of electromagnetic force and that the "hand of the strongest weightlifter will crumble under the weight of a feather" if electromagnetic forces did not exist.  I imagine that it was due to some kind of attraction or repulsion between charges in the bodies. But I still cannot understand what exactly the statement tries to say. It also considers friction as a kind of normal reaction, so, I don't understand how the force actually sets up


i need some help with a java code,  This is my code:  public void showData() {          int pass = 0;          /* For first list */         for(int i = 0; i < first_list.length; i++) {              if(first_list[pass].toString() != second_list[i].toString()) {                 System.out.println(first_list[i]);              } else {              }          }          pass++;     }   The output:   Porto  Algarve   But i dont want this and i understand that by doing this way, my for ends and dont do other passes.. i want to get all possible combinations without repeat words, the output that i want is this one:   Porto Algarve Lisboa Algarve Lisboa Porto   This is a draw to help understand:   How can i do such thing? Thank you!  EDIT: Im not asking how to compare strings... if someone can point me a topic with what i want, it would be nice, if not.. well some advices would be great


What specifically does the "awakens" in "The Force Awakens" refer to?

I checked the Wikipedia article and some interviews, and haven't found any specific answer.  What specifically does the "awakening" of the Force in the title refer to?  Was the Force somehow asleep or dormant? (which would, since it Binds The Galaxy Together, explain the Inflationary cosmological models).  Or that there were no active Force users since Vader and Sidious offed every Jedi and then each other? We know Luke's still around.  Or something else?  Canon or word-of-god answers only, please.


How do you use character variables in Bash for if statements?

For example I have something written like this read -p "Enter a character: " variable if [ $variable -eq 'A' ];  I'm getting an error that says integer expression expected, but I don't want to use an integer variable I want to use a character?


Suppose $f : [0,1]\mapsto R$ is continuous, $f$ is differentiable on $(0,1) $and $f(0)=0$.

Assume $|f'(x)|\le |f(x)|$ for all $x\in(0,1).$ Prove that $f(x)=0$ for all $x\in[0,1]$.  I thought maybe I could use the limit but since there is no equation it won't work.


What should I do when a professor is teaching inaccurately?

I have a professor who is teaching an upper class man renaissance art history course. I am very passionate about this subject so I already have lots of prior knowledge. I found some inaccuracies in her lectures and tried to confront her about them, providing sources and all. She still insists she is correct and graded me unfairly. Again, this is an upper class course and she teaches it like an introductory level course. The information she provides is inaccurate and she teaches by asking us to a memorize each picture and its statistics (name, date, medium, size, location), and covers none of the historical elements of the piece artist or era. I'm very frustrated with her and I'm not sure what to do.  Any advice would be greatly appreciated. Thank you.


What does InitializeComponent() do, and how does it work in WPF?  In general first, but I would especially be interested to know the gory details of order of construction, and what happens when there are Attached Properties.


getTypeName() of NetworkInfo returns mobile eventhough connected to WIFI on mobile device

In the following code, the activeinfo.getTypeName() returns mobile even when connected to wifi. I read somewhere that wifi will not be detected on emulator so I even tried it on my device. But it still returns either mobile - when connected to wifi or mobile data (I even tried turning off the mobile data and just using the wifi instead of turning on both)- and "not connected" when i turn off both the wifi and mobile data.  ConnectivityManager conmgr = (ConnectivityManager)getSystemService(Context.CONNECTIVITY_SERVICE);     NetworkInfo activeinfo = conmgr.getActiveNetworkInfo();     WifiManager wifi=(WifiManager) getSystemService(Context.WIFI_SERVICE);     Log.e("sometag", activeinfo.getTypeName());     String ssid;      if(activeinfo!=null && activeinfo.isConnected())     { //eventhough the following comparison is wrong, the next else should return "wifi" right? well, it doesn't.          if(activeinfo.getTypeName()=="WIFI")            {              WifiInfo w=wifi.getConnectionInfo();             ssid= w.getSSID();           }         else         {             ssid = activeinfo.getTypeName();         }     }     else         ssid= "not connected";


iPhoto had it's own trash, and when you've emptied it, files moved to the system trash. I cannot find this in the new Photos app. When I delete files, they don't appear in the system trash.


Which JDK version is compatible with Netbeans on Ubuntu?

I'm trying to install Netbeans on my Ubuntu. It was successfully installed but was unable to create new projects or new files. I have installed JDK 12 and then I removed it because I found here a solution that recommended removal of latest versions of JDK and set JDK 8 as default. I did what solution said but now I can't install JDK 8. It is showing me this error message:   E: Package 'oracle-java8-installer' has no installation candidate    So I started searching on the Internet about the solution and I found that "Oracle Java (JDK) 8 Installer PPA (DISCONTINUED)".   What should I do now?


Why a brain's hemisphere controls the opposite side of the body?

As a physics student with very little understanding of biology, in a course about physics foundations diagnostic techniques I have come up with this question. I don't even know if it does make sense or not; in the latter case, please excuse me.   As far as I know, in the human brain the right hemisphere controls the motion of the left side of the body, while the left hemisphere controls the right side. Moreover, the part related to sight is on the back of the brain.  To me, it seems that there is a sort of opposition between the part of the body considered and the area of the brain that have to control it. Is this statement right? Only for human beings or also for animals? Are there any exception to this sort of pattern (if there is anyone)? Is there a logical reason to the fact that we show this characteristic and it couldn't be different from how it is?


apt update shows neon kde repo link error

Recently I use apt update on my machine and it gives me the following error: E: The repository 'http://archive.neon.kde.org/user xenial Release' does not have a Release file. N: Updating from such a repository can't be done securely, and is therefore disabled by default.  Here is my lsb_release -a output: No LSB modules are available. Distributor ID: Ubuntu Description:    Ubuntu 16.04.7 LTS Release:    16.04 Codename:   xenial  I went to that link no file was found there. What should I do now?


I have to draw function with \plot but it says "Dimension too large", this is my code:   \begin{tikzpicture}  \begin{axis}[grid=major, xmin=0, xmax=3, ymin=-1.5, ymax=1.5, xlabel=$t$, ylabel=$x(t), y(t)$, scale=0.3]  \plot[blue] plot[samples=100, smooth] expression{(1 + 2 * x)*exp(-2*x) * sin(280* 3.14 * x)};  \plot[red, dashed] plot[samples=100, smooth] expression{ (1+2*x) * exp(-2*x)};  \end{axis} \end{tikzpicture}   Hope you can help me because I need it in few days, there are picture how it should look:    and this are functions:


How would I create a text file and fill it with sudo permission in bash

I'm trying to create and fill a file in a directory that requires sudo permission.   EDIT: It seems that based on tested the suggested similar post.  sudo su -c "echo 'put in file' > file_name" echo "Some text" | sudo tee /etc/file   will both create a file within the directory that requires sudo permission


How to restore MacBook Pro to factory settings? Prohibited sign on boot

Because I am selling my old MacBook Pro (13-inch, 2011) and, for this reason, restore it to the factory settings. I have followed the steps for this. First the discs were erased which only partially succeeded. In the next step "reinstall macOS" I now get a gray screen and I can't get out (even after I turned off the laptop).   How can I proceed from here?


Can I have my sound muted when head phones are not plugged in?

On my Macbook, I could have different "audio profiles" depending on whether or not headphones were plugged in.  I'd have my speakers on mute, and when I plugged in my headphones it would unmute.  This was great at the office in case any web pages I wasn't supposed to be on suddenly popped up with some video of cats playing piano or what not.  I switched to a new Windows laptop that runs Windows 8.1, however there doesn't seem to be a way to do this.  My mute status and volume stays the same regardless of whether or not I have head phones plugged in.  Is there a way to configure Windows to mute the sound unless headphones are plugged in?  Seems like a basic feature.  Update:  I have a Realtek HD Audio driver (Stock Windows 8.1 driver).  I've already checked, and the driver does not remember volume levels so I can't just turn the volume all the way down.  However, it does pop up a notification when I plug in headphones telling me that I just plugged in headphones, thus the hardware is capable of telling the difference.  Update 2:  I installed the latest drivers from Realtek.  I now have a Realtek HD Audio Manager that pops up when I plug in headphones.  However, it still does not remember audio levels or mute status when I plug in or unplug headphones, nor can I find any features in the Audio Manager for that sort of thing.  From what I can tell, this is a driver feature and not an OS feature, and my drivers simply don't support that.  Bummer.


Insert command with keyboard shortcut in TeXstudio

For inserting dashed lines inside matrix structures, I have to use the command \hdashline from the package  arydshln prodominantly. I am wondering whether TeXstudio supports assigning a specific command or statement to a certain keyboard shortcut.  So more explicitly:  assign \hdashline[2pt/2pt] to the key combination Alt+Shift+0 (any combination will do).


Parsing an Int from a string in javascript

In javascript, what is the best way to parse an INT from a string which starts with a letter (such as "test[123]")?  I need something that will work for the example below.  My JS:  $(document).ready(function() {      $(':input').change( function() {         id = parseInt($(this).attr("id"));  //fails for the data below         alert(id);     }); }   My generated HTML:  <select id="attribute[123]"> <!-- various options --> </select> <select id="attribute[456]"> <!-- various options --> </select>   Thank you!


I am helping a retired professor to migrate from his old computer (old Mac OS), that has TeXtures installed. The company that created TeXtures is gone, so I am looking at MacTeX, combined with TeXShop, which seems to be a good replacement.  He has an extensive amount of TeX documents and I am testing the workflow.  Everything looks good except for one minor issue: he uses a lot of custom macros, he wrote and accumulated over the years. His workflow in TeXtures depended on these macros along with higher level macros.  Here is my question.  Is there a user directory, where these macros can be placed, so TeXShop will find them?  It seems there is a user library structure created in ~/Library/TeXShop/Macros. Is that the correct location?


What is the command in the terminal to update Vim on Ubuntu?

I'm on Ubuntu 12.04 and want to know how to update Vim via the command line. What is the command to update this?


How do you remove a specific revision in the git history?

Suppose your git history looks like this:  1 2 3 4 5  1–5 are separate revisions. You need to remove 3 while still keeping 1, 2, 4 and 5. How can this be done?  Is there an efficient method when there are hundreds of revisions after the one to be deleted?


'No Such File or Directory" Error When Working with Shared File

I'm attempting to open a file on a Linux computer through file sharing. The file is stored on a Macbook Pro and both computers are running Blender 2.77. However, when I try to open the file on the Linux computer, I get an error of, "No Such File or Directory." I don't think this is a file permissions error as my permissions settings are set so that "Everyone" can read and write my file. What can I do to solve this?


Wifi drivers won't work after I upgraded kernel to 3.4 for ubuntu 12.04

My wifi support got broken after I upgraded my kernel from 3.2 to 3.4 for ubuntu 12.04. I know I need to use sudo apt-get install firmware-b43-installer but whenever I type it into terminal, I get:  Reading package lists... Done Building dependency tree        Reading state information... Done E: Unable to locate package firmware-b43-installer   I also tried using synaptic package manager but when I search for firmware-b43-installer I don't see any options. Check box for Proprietary drivers for devices (restricted) has also been selected from Settings->Repositories but I still don't see firmware-b43-installer.   Running lspci -vvnn | grep 14e4 command on the terminal gives:   02:00.0 Network controller [0280]: Broadcom Corporation BCM4331 802.11a/b/g/n [14e4:4331] (rev 02)   I am worried that I may have deleted some important package while trying to fix wifi. Please help I am very new to Ubuntu.


This issues had been in my life for 2 weeks and I was unable to figure it out.  My domain name was hosted by 1&1 and my website is hosted by my own Ubuntu 18.04. I have no issue to ping anywhere and my website has no issue to visit.  However I can't update or upgrade my Ubuntu server with the following error message:  my nameserver shows this:  nameserver 127.0.0.53 options edns0   Thank you in advance for help.  sudo -E apt-get update Err:1 http://archive.ubuntu.com/ubuntu bionic InRelease   Cannot initiate the connection to archive.ubuntu.com:80 (2001:67c:1560:8001::1                                                                                1). - connect (101: Network is unreachable) Cannot initiate the connection to ar                                                                                chive.ubuntu.com:80 (2001:67c:1360:8001::21). - connect (101: Network is unreach                                                                                able) Cannot initiate the connection to archive.ubuntu.com:80 (2001:67c:1360:800                                                                                1::17). - connect (101: Network is unreachable) Cannot initiate the connection t                                                                                o archive.ubuntu.com:80 (2001:67c:1560:8001::14). - connect (101: Network is unr                                                                                eachable) Could not connect to archive.ubuntu.com:80 (91.189.88.162), connection                                                                                timed out Could not connect to archive.ubuntu.com:80 (91.189.88.24), connection                                                                                timed out Could not connect to archive.ubuntu.com:80 (91.189.88.149), connectio                                                                                n timed out Could not connect to archive.ubuntu.com:80 (91.189.88.31), connectio                                                                                n timed out


Problem: Find the number of twelve-card hands containing four cards in each of three suits.   My solution:   pick a suit : 4 ways. choose 4 cards from the 13 in that suit: ${^{13}}{C}_{4}$ ways. pick another suit: 3 ways. choose 4 cards from the 13 in the new suit: ${^{13}}{C}_{4}$ ways. pick the final suit: 2 ways. choose 4 cards from the 13 in the final suit: ${^{13}}{C}_{4}$ ways.   Hence, total number of ways is $4\cdot{^{13}}{C}_{4}\cdot3\cdot{^{13}}{C}_{4}\cdot2\cdot{^{13}}{C}_{4} = {^{4}}{P}_{3}\cdot\left({^{13}}{C}_{4}\right)^3 $ total hands.   This is the incorrect answer. Why?


Prove that in an ordered field, $0\cdot x=0$ for every $x$

Prove that in an ordered field $0\cdot x=0$ for every $x$.   I'm not sure how to go about proving something is true in an ordered field. What are the steps involved?


what should be placed in the blank and why?

He as well as his friends _____ going to play cricket in that playground.


In Star Trek: Deep Space Nine, how is Odo able shapshift his comm badge?

In Star Trek: Deep Space Nine, one of the characters, Odo is able to shape-shift into other forms, including his humanoid form. When he is in his humanoid form, he is able to form clothing. That makes sense, but what about the comm badge? That is technology and is fully functional. I don't remember that being explained in the series, so this bothers me. Other changelings also pulled this off, like when a changeling impersonated Dr Bashir for a while. To my understanding a changeling should not be able to produce technology when they change shape. But how is that possible?


I have vague recollection of a book (possibly a short series) that involved a bottle trap. When you interacted with the bottle, you were sucked into it and found yourself in a multi-level 'dungeon'. I think there might of been a bottle at that bottom to get yourself out. The same book might have had something about having slow conversations with stones, but it might not and I am really just interested in the bottle concept. It certainly was not written this century. If I had to guess, I would say the 80's, but that is only a guess.


On click of a dynamically created element

I added a div element into a variable and appended it to the document:  var faceDiv = $("<div class='dropDownJsFace dropDownJsArrowDown' />");   Now I'm attempting to reference that div within the .on() function via e.target like so  $(document).on("click", function(e){     if(e.target == faceDiv)     {         alert("done");       } });   To clarify, I want it to specifically reference that dynamically created div, as apposed to the class .dropDownJsFace.


How to print a regular file to pdf from command line

In gedit, printing a file gives an option of printing to file where the file can be saved as a pdf. How can I do the same thing from the command line?


Why would Windows 7 say I'm low on memory when I appear to gave 2GB+ free?

Why would Windows 7 say I'm low on memory when I appear to gave 2GB-3GB of free RAM? (on a 12GB machine)  Surely 2.2GB+ is quite a lot of free RAM and it shouldn't be warning me at this stage?  Also what's the difference between "Free" and "Available"?


Set Hyperlink Field Using SPD 2010 Workflow

I've been doing a LOT of research to try to figure out how to do this, but nothing is working. I have a column named "Update Item" that I want to be a link to start a workflow. I have workflow setup that will populate that field. The first step sets a workflow variable to   "https://www.mysite.org/site/_layouts/IniWrkflIP.aspx?List={f5c87ae4-1796-4310-aeb0-1e57edef6f87}&[%Current Item:ID%]&TemplateID={5773b102-16f1-4d45-9767-cb26db3bd72c}&Source=https://www.mysite.org/site/"    without the quotations. The second step updates the current item's "Update Item" field to the value of the workflow variable. When running the workflow, it errors out saying "The workflow could not update the item, possibly because one or more columns for the item require a different type of information." The only thing I can think is that since the variable is set as a string, the hyperlink column can't be updated to that value.   I've tried replacing   [%Current Item:ID%] with {ItemID} per the suggestion of another site.    The workflow didn't fail, but the URL did not render correctly. Please help.


Why is $\operatorname{Div}\big(\operatorname{Curl} F\big) = 0$? Intuition?

Why is $\operatorname{Div}\big(\operatorname{Curl} F\big) = 0$? Is there an intuitive explanation to what this means as well as an algebraic proof?  Also I understand that $\operatorname{Curl} \operatorname{Grad}F =0$, I interpet this as the gradient not having any rotation since its the direction of steepest ascent and if this formed some sort of loop this would not make sense? Is this somewhat correct? Any explanations would be appreciated.


Suppose $G$ is a group of order 4. Show either $G$ is cyclic or $x^2=e$.

I've figured out that if I know $G$ is not cyclic, then it for any $a \in G, o(a) \neq 4$ (or the order of any element in group $G$ is not 4).  I know ahead of time that the elements in the group ($\forall x \in G$) must have order $o(x)=k$ where $0 < k \leq 4$ where $k \in \mathbb{Z}$, so $k = 1, 2, 3, 4$.  If $G$ not cyclic, then we know $k \neq 4$ so we have $k = 1, 2, 3$ left.  I know how to show that $k \neq 3$ but I am not sure if I am supposed to do it for all possible $k$ because obviously if our order was higher (let's say $n$) then it would get messy. It ends up being in this case that $k = 2$ is good and $k = 1$ is trivial. I have looked up online and it says using Lagrange's Thm we know it has to be $k = 1, 2$ since $3 \nmid 4$, but I cannot use that theorem as we have not have learned it in class. How can I show that $k = 1$ or $2$ in another way?  However working from using the result that if we have $x \in G$ and $H = \langle a \rangle$ and knowing that $\left\vert{H}\right\vert=1$ or $2$, then $x^2=1$ for either case. Then I am done right?  What is another, cleaner, better way of trying to answer the question in the title?  I apologize if my formatting is poor since I am new at LaTeX and extraordinarily bad at algebra it seems. Thank you in advance.


How to detect the desktop environment in a bash script?

I am writing a bash script that needs to know which desktop environment (XFCE, Unity, KDE, LXDE, Mate, Cinnamon, GNOME2, GNOME3,... ) is running.  How can I obtain that information?


Is there a regular expression that matches valid regular expressions?   (I know there are several flavors of regexps. One would do.)


Are features that allow −5 to attack to get +10 to damage mathematically sound?

Some class features, monster traits, and feats allow you to take a −5 to your attack roll in order to gain a +10 to your damage roll. At first glance this looks really good, but when will it deal more damage than not using it on average?  For instance if you have a total attack bonus of +8 and you deal 1d12 damage. You have to roll a 7 to hit an AC of 15. If you take the −5 that makes it where you have to roll a 12. That's going to reduce your average damage by a lot.


Collect data with central management servers and keep them in local table

I have 50 servers. I manage them from a central management server.   I could open a query and get result for each one at the same time. But I want to do it in an automated way, like a job, to collect data from each server and store/handle it locally.  Is this possible and if so, how?


How to convert "animated" text in a document to static text?

When I analyze the output from Racon, which I got on GitHub, it has dynamic "animated" text as the output from the STDERR.  For example, when I cat the file, it looks like this:     [racon::Polisher::initialize] aligned overlap 624/2265116   The text then "animates" and overwrites itself to say the next number:     [racon::Polisher::initialize] aligned overlap 1954/2265116   The end result is that there are 220 megabytes worth of data stored in 7 lines.  I would like to get each of these steps listed individually, but when I analyze the text with any text editor, it crashes.  The only tools I have available to me are command line tools.


I have two newly set up Minecraft 1.8.9 servers.  With both servers when I point my Pocket Edition clients to them I receive an "Unable to connect to world." message.  1) Debian 8 2) CentOS 7  [root@minecraft Downloads]# java -version openjdk version "1.8.0_65" OpenJDK Runtime Environment (build 1.8.0_65-b17) OpenJDK 64-Bit Server VM (build 25.65-b01, mixed mode)   Both servers behaving the same way, I did a packet capture on each and can see UDP traffic reaches each them.  And both servers respond with ICMP Port Unreachable.  No surprise since the UDP port is not open I found.  Minecraft server is only opening the TCP port...  [root@minecraft Downloads]# netstat -anp |grep 25565 tcp       0      0 0.0.0.0:25565           :::*                    LISTEN      21202/java   I looked through Minecraft's server.properties documentation and see nothing pertaining to the protocol being configurable, only the port.


Can we omit "who is" in relative clauses? (noun + noun)

I went down yesterday to the Piraeus with Glaucon the son of Ariston, that I might offer up my prayers to the goddess (Bendis, the Thracian Artemis.); and also because I wanted to see in what manner they would celebrate the festival, which was a new thing. - The Republic of Plato.   Glaucon is the son of Ariston, right? I suppose it should be Glaucon who is the son of Ariston. Can we omit that?


Holomorphic functions: is it true that $f(\bar{z})=\overline {f(z)}$?

Is it true that  $ f(\bar{z})=\overline {f(z)}$, Where z is complex?  I think it holds when $f(z)$ is holomorphic since we have $f(z)=p(x,y)+iq(x,y)=p(z,0)+iq(z,0)$ Any help...


Have Biblatex display only the first of first names for an author

I am looking for a way to force biblatex to strip all first names except the very first one. I am actually using only initials, but even that gets messy when the author has 3-4 first names in a row and is known only by the first one.  Say I am citing this guy:  John Paul Peter Julian Doe   the output will be:  J. P. D. J. Doe   which is already quite long. Removing the dots and thin-spaces is not really an option. I would like it to just end up being J. Doe for the in-text (cbx) part of the reference.  Based on , I suppose it is possible with biblatex+biber and it is the solution I would favour.


Change the color of the "remark" environment in Beamer

I would like to change the color (bg and fg) of the remark environment in a Beamer document. I have setup my document using:  \usetheme{AnnArbor} \usecolortheme{crane}   I read in some other question that I should use something like:  \setbeamercolor{theorem text}{fg=black}   or something like  \setbeamercolor{block title example}{bg=orange,fg=white}   I have tried both, using remark or rem instead of theorem or example to no avail. I have to make it clear that I don't want to create a new environment, as I use Lyx and I need to stick to the default "remark" environment, only modified through the preamble.  UPDATE  I have checked that Lyx adds the following definitions to the preamble:  \theoremstyle{definition}      \newtheorem*{defn*}{\protect\definitionname}   \theoremstyle{remark}   \newtheorem*{rem*}{\protect\remarkname}   \theoremstyle{definition}   \newtheorem*{example*}{\protect\examplename}   \theoremstyle{plain}   \newtheorem*{fact*}{\protect\factname}   \theoremstyle{definition}   \newtheorem*{problem*}{\protect\problemname}   \theoremstyle{definition}   \newtheorem*{xca*}{\protect\exercisename}   Is this a Lyx related question instead of a Beamer one?