How to connect to remote X-Server (logged in via ssh)

When I'm logged on to another host (e.g via ssh), how do I connect to the XServer of that machine (same user is logged in and is running a desktop (gnome))?  You may ask way I wish to do that: There are commands that don't open an X-Window, e.g. xinput, xhost, etc.. and there are situations where you want to run them from remote.


How to scale all fonts (in the whole document) by certain factor or percentage?

Is there a way to scale the font size of all text in a LaTeX document by a certain factor, something like \scalealltext{factor=0.95}?  Edit: Text should reflow, so as to fit (a bit) more text on a page and ultimately trim down the number of pages.  Edit2: Apart from wanting to apply it to a specific problem, my question is more general. So giving specific fonts for the specific document I had when this question was raised is IMO not of much use.


Does Ubuntu 18.04 ARM miniiso work correct as main OS on Teclast T8 4/64 Gb ? I am primarily interested in touchscreen functions

IDK anything about this brand, but people on forum says that GNOME works good with touchscreen


Is it possible to slow down system clock?

I'm playing a game that is using JavaScript to get system time, and I need the best time in the game I can get, I tried Cheat Engine but, as I said game uses JavaScript, so it is of no help to me. I tried SleederXP, but it didn't help either. I have Ubuntu installed so I tried libfaketime but I didn't know how to use it on Firefox. So is there a way to slow system time on Windows, for example that 5seconds real time is shown as 1sec?


Looping through a custom query makes WordPress assume another template

I am calling this code from my custom sidebar, in order to get related postings from the same category:  query_posts(array(    'cat' => get_category_id(),    'showposts' => 5,    'post__not_in' => array(get_the_ID()) ));  get_template_part('article-list'); // outputs the posts   This works. The have_posts()-loop inside of my article-list.php now only outputs 5 other postings from the category.  But this also causes a problem: No matter on what kind of page I am (single.php, index.php, ...), WordPress always assumes that I am in the category template. So is_category() always returns true after calling query_posts('cat=...'). Thus is_single() returns false, although the single.php-template is used.  What can I do to tell WordPress that it is still using the single-template? Or: What other function can I use to detect which (main) view is loaded?


If I counterspell with subtle metamagic, can my counterspell be counterspelled?

BBEG casts a spell, I counterspell, and the mob has a chance to counterspell my counterspell under normal circumstances, leading to a wasted slot and some hurt from the incoming spell.  If however I cast counterspell with subtle metamagic, am I right in thinking that this counterspell itself cannot be counterspelled as there is no way to identify that i'm casting this spell?  Subtle casting: "When you cast a spell, you can spend 1 sorcery point to cast it without any somatic or verbal components."


The text xticks are not placed on the same line, rather the same height counting from the highest letter (zero is much higher than high and low).    How can you fix this?  MWE:  \documentclass[class=scrartcl,14pt]{standalone} \usepackage{fontspec} \usepackage{luatex85} \usepackage{unicode-math} \usepackage{tikz} \usepackage{pgfplots,pgfplotstable} \usepackage{calc} \usepgfplotslibrary{groupplots} \pgfplotsset{compat=newest}  \begin{document}  \begin{tikzpicture} \begin{groupplot}[group style={group size=1 by 1, horizontal sep=2cm, xlabels at=edge bottom }, %~ yticklabel style={/pgf/number format/fixed}, %~ xticklabel style={/pgf/number format/fixed}, scaled y ticks = false, scaled x ticks = false, xtick pos=left, ytick pos=left, %xlabel=time (week) ] \nextgroupplot[xmin=0.5,xmax=3.5,xtick={1,2,3},ymin=2.43,ymax=3.05,xticklabels={zero, low , high}, xlabel={label}]  \end{groupplot}  \end{tikzpicture}  \end{document}


White rectangle covering hot question in Android app feed

I noticed a small white rectangle over the title of the hot question displayed in the feed:        Can this please be fixed?


Let $H\le G$ and suppose that $[G:H]$ is the least positive prime factor of $|G|$. How to show that $H\triangleleft G$? I am confused in how to establish relation between the number of cosets of $H$ and its normalization. What does the condition "least prime factor" restrict for? Where should I begin?


I'm trying post base64 code to save as an image but I can't post the value of textbox when I try submit my base64 code.  Is there limit send to codes via posting form?  I get an error due to can't get the value of textbox below:     ADODB.Stream error '800a0bb9'      Arguments are of the wrong type, are out of acceptable range, or are in conflict with one another.   My HTML code  <form method="POST" action="?X=1" id="myForm">     <input type="text" name="img_val" id="img_val" value="" />     <input type="submit" value="Submit Largest Code" /> </form>   My ASP codes:  <%  IF LEN(Request("X"))>0 THEN  base64String = Trim(Request.Form("img_val")) Set tmpDoc = Server.CreateObject("MSXML2.DomDocument") Set nodeB64 = tmpDoc.CreateElement("b64") nodeB64.DataType = "bin.base64" nodeB64.Text = Mid(base64String, InStr(base64String, ",") + 1) set bStream = server.CreateObject("ADODB.stream") bStream.type = 1 call bStream.Open() call bStream.Write(nodeB64.NodeTypedValue) caminho=Server.MapPath("/SS/imagem.png") call bStream.SaveToFile(caminho, 2) call bStream.close() set bStream = nothing  END IF %>   Sample Base64:  data:image/png;base64,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


Is there any theorem related to this statement that $ac= qn +1$ is true for some $q \in \mathbb{Z}?$

This is a problem taken from chapter $1$ of Dummit and Foote book Show that  if $n$  is not prime  then $ \mathbb{Z} / n \mathbb{Z}$ is not a field My attempt : I got this answer from solution manual of Dummit and Foote  written by James Ha Consider  the set $\mathbb{Z}/n\mathbb{Z}$ for $n$ is not prime then there exist  positive integer  $a, b$ such that $ n= ab$ and $ a, b >1$ . Suppose there exist a multiplicative inverse $\bar c$  of $\bar a $.Then it must  be true  that $ac= qn +1$  for some  $q \in \mathbb{Z}$ .However  ,$n=ab $ so $ac= qn +1 = q ab +1$ from which it follow that  $a(c-qb)=1$ .This is impossible  because  $a> 1!$ So $\bar a$ has no inverse  in $\mathbb{Z} /n \mathbb{Z}$ and $\mathbb{Z} /n\mathbb{Z} - \{0\} , .)$ is not a group. we  must conclude that  $\mathbb{Z}/n \mathbb{Z}$  is not field  for $n$  not prime My Doubt: I'm not getting this line  then it must  be true  that $ac= qn +1$  for some  $q \in \mathbb{Z}$ My confusion is that why  it is written that $ac= qn +1$  is true for some  $q \in \mathbb{Z}?  $ Is there any theorem related to this statement? I was searching this related statement in Dummit  Foote book  but didn't found its


"Not with a whimper, but with a roar of triumph!"

Looking for the title of an old sci-fi book, pretty sure it is a Baen or Del Rey imprint. Basically, mankind has reached the stars and expanded throughout the galaxy. Suddenly, an unknown race appears and begins a war of extermination against man. Finally, the galaxy is desolate, and one man remains. He is in a starship with an AI and becomes injured in the battle.  The ship's AI takes over and speeds out into the unknown, followed by the last remaining member of the unknown alien race. As all speeds are at tremendous multiples of the speed of light, the man cannot get away, but the alien cannot catch up.  Finally, communication is opened, at which point the man asks "why?" The alien tells him that man had discovered immortality, but that it required the death of a member of a race known as the Flower People for every human who achieved immortality. The alien says that Man would have found the answer eventually, but that genocide was so intolerable that the aliens came from another dimension, to which they could never return, to stop Man, which resulted in the war of extermination.  Finally, the light speeds become so great that the two remaining living beings in the universe approach the Big Crunch. As the Man begins to dive into the singularity, with the alien hot on his heels, he says that maybe there will be room in the next universe for both races to live in peace, and the final line is "not with a whimper, but with a roar of triumph"!


After two visa refusals, how do I explain why I want to go to Portugal?

I was refused a French visa and now I got a refusal from the Latvian Embassy. I do not understand the reason:      The information submitted regarding justification for the purpose and conditions of the intended stay was not reliable.    When I apply to the Embassy of Portugal, how do I explain? Is the previous refusal letter necessary in a new file or not?


Does the mass of an electron change with its "energy state"?

When an electron absorbs a photon, it gets into a higher energy state and goes into the upper orbit/shell.  Does (rather should) this absorption of energy also have an impact on its mass (although incredibly small)?  Can we even measure the mass of an electron while it is it still bound to the nucleus?


Organize desktop icons on Windows into categories or sections

I want to organize my Windows desktop icons by categories. Multimedia, system tools, editors, etc. I need to define rectangular areas of the desktop, then place the shortcut icons. They would stay locked into place forever in the category until I moved them. The standard windows desktop won't do this, and folders aren't going to do what I want either.   How can I set this up on my desktop on Windows?


Is there a better way to transfer my "\newcommand"s from document to document?

I do physics and math, and so I have accumulated many different "\newcommand"s that make my life much easier that depend really only on the three packages amsmath, amsthm, and amsfonts.   My question is this:   What is the best way for me to carry them from document to document, other than merely copy and pasting all of the new commands into one huge, disgusting preamble? Ideally, I would like to be able to do something as simple as just having a single text file that I call, but it seems a bit more involved than that.


Why does blender allow me to rotate an HDRI?

I can take a plane, cover it in grass and drop it into an HDRI meadow for background lighting. Parts of the meadow are dark others not. Awesome... Except, my plane is tiny and my HDRI meadow is huge. Blender allows me to rotate the HDRI so that I can put the dark bits on the left, or the right. But what I really want is to stretch the plane, or shrink the HDRI, so that the plane really looks like it is at the same scale dropped into the background HDRI. If I type in two scale values then the HDRI stretches unpleasantly, but as soon as I type in three identical scale values it takes me right back to the start again. Why is rotation of the HDRI allowed but not scale or translate. Or maybe it is allowed and I'm just messing up?


Are there other interjections to substitute for "jeez", "good grief", "oh my god", "and other interjections containing religion?

I would like to know if there are interjections expressing exasperation, annoyance, anger, frustration without connection to religion. Preferably doesn't originate from it either. No euphemism too. Much appreciated.


find the point of convergence of sequence {$a_n$}

Let $\displaystyle a_n= \sum_{k=1}^{n} \frac{n}{n^2+k}$, for $n\in \mathbb{N}$. Then what is the nature of sequence $\{a_n\}_{n\in\mathbb{N}}$.  I tried using the Cauchy's general principle of converges for a sequence. But I think that this won't help me as because:  $\displaystyle a_{n+p}= \sum_{k=1}^{n+p} \frac{n+p}{{(n+p)}^2+k}$ and $\displaystyle a_n= \sum_{k=1}^{n} \frac{n}{n^2+k}$  And now if I do $a_{n+p}-a_{n}$ then this won't even cancel a single term.  $a_1$ will have one term.  $a_2$ will have two terms, and so on.  But here the first term in $a_2$ is not the term of $a_1$.  and due to this problem I was unable to use any results of convergence of series of positive terms.  Any help/hint will be appreciated.


Why “characteristic zero” and not “infinite characteristic”?

The  (with unity, say) is the smallest positive number $n$ such that $$\underbrace{1 + 1 + \cdots + 1}_{n \text{ times}} = 0,$$ provided such an $n$ exists. Otherwise, we define it to be $0$.   But why characteristic zero? Why do we not define it to be $\infty$ instead? Under this alternative definition, the characteristic of a ring is simply the “order” of the additive cyclic group generated by the unit element $1$.   My feeling is that there is a precise and convincing explanation for the common convention, but none comes to mind.  I couldn't find the answer in the Wikipedia article either.


Have a Malformed Sources.List line and Don't Know How to Correct It

I recently upgraded to Ubuntu 20.04. I tried about 4 different commands to install Tor browser and the first 3 failed. Finally I found step-by-step instructions from HowToGeek.com and they worked perfectly. The problem seems to be that one of my botched installation attempts messed up my list file. The error message I get when I try to install, reinstall or remove ANYTHING, including ubuntu-software (which does not launch at all), is: E: Malformed entry 2 in list file /etc/apt/sources.list.d/tor-project.list (Component) E: The list of sources could not be read.  I read many of these Q&A's and managed to find the actual line that is corrupted. The two lines read: deb [arch=amd64] https://deb.torproject.org/torproject.org focal main deb [arch=amd64] https://deb.torproject.org/torproject.org  main  How do I know what to change line 2 to? I thought maybe the issue was just an extra space between .org and main that I can see in the code but doesn't show up in the HTML above, but I changed it and still could not apt update. Is it possible to just delete both lines since Tor itself is working perfectly already?


When will my device get the Android 7.0 update (Nougat)?

Android Nougat .  It adds features such as multi-window support.  You can review the high-level changes at .  Of course, not all devices will get this update right away, even at release; others won't get it at all. Manufacturers and carriers often choose to add their own custom modifications, which tend to delay the official release.  When will each device get Nougat, either officially or unofficially, if ever?  See also:


How do I get curly brackets to show in the output file on share latex? I tried putting them in the input file, but they disappear in the output.


In a for loop, because the last (update) expression cannot involve assignment, is it trivial whether it uses prefix or postfix increments/decrements? For example: for (int i=0; i < 10; i++) {...}  vs. for (int i=0; i < 10; ++i) {...}  Would there ever be a case where doing a prefix or postfix would matter in the update expression of a for loop?


Today, I answered to many questions and I won points with up votes or validated answers. But, when I go in the , I can see some up votes are not counted.  For example, I answered to a question and, until now, my answer has been validated and got 7 up votes. So I should win, if I'm not wrong, 7x10 + 15 = 85 points. But, if I look the reputation tab, I see I only won 15 points.  So I would like to know why points are not counted ? The problem comes, probably, from me, but I don't know from where.


When updating, is using "sudo apt-get update" the same as using the GUI update on desktop?

Is using sudo apt-get update the same as using the GUI update on the desktop?


I am the current maintainer of a biggish legacy wx python app. It was a community work and although had quite a bit of engineering thrown in, it was developed without any tests. I want to set up a testing repository to amend this situation so at least some critical parts of the code as well as new code can be developed with unit tests. My question is how to set up the test package. The  repository is structured as:  .git/ Mopy/   bash/  # all the code is here     package1/     package2/     ...     module1.py     module2.py     ...   Seems simpler to have it in another repository - but how would I structure it ? How am I to import the classes to test ? Are there any standard conventions in python (as in src/test/java for maven) ?  I am familiar with JUnit etc - so this is not about how to write the tests - only about how to structure the testing package and importing the classes/bootstrapping it.


How to WRITE to ext4 partitions on windows?

I've tried many of the answers found here. Even the ones that supposedly could write to the SD card, won't work. When I eject the card and put it again the file is like it was before the write.  So how to write to SD cards in windows? I just need to edit a text file with notepad++.


Out of the three, which is the best option and with which grammatical rule:        I have four dozens of mango.   I have four dozen of mangoes.   I have four dozens of mangoes.


Which packages can be using for writing authors names and affiliation?                      thank you in advance


I've seen that some words in English are pronounced with the /ɪ/ sound when the vowel is not stressed.  Some examples include: pocket /ˈpɒkɪt/, comet /ˈkɒmɪt/. But hundred /ˈhʌndrəd/.  Is there any pronunciation rule here when the words end in /t/?


I know that both "more" and "else" can be used in the meaning of "besides". Well, at least I think so. Here are examples:   I have told you all I know. What else do you want with me? I have told you all I know. What more do you want with me?   As far as I am aware, the later is less common but carries the same meaning as the former sentence.  For this not to sound like a duplicate, here's the main question: Can "else" and "more' work in an identical way in the following sentences with the words "anything, something, whatever, whenever, wherever, whomever, whoever, someone, somebody, and everything"?   I've already helped your mom and sister. Is there anyone more you want me to help? That's it. I can't help him. There's nothing more I can do!   Edit: It's not a duplicate. I'm not asking about the difference between "what else" and "what more". I'm asking about using "else" and "more" with words "anything, something, whatever, whenever, wherever, whomever, whoever, someone, somebody, and everything".


Handler return null Exception and sending null in message

Here is my handler code in which i set my progressbar in oncreate() method       progressBar = (ProgressBar) findViewById(R.id.progressBar);      thread = new Thread(new MyThread());      thread.start();      handler = new Handler() {          @Override         public void handleMessage(Message msg) {             progressBar.setProgress(msg.arg1);                            }        };        if(progressBar.getProgress()==99)     {         Intent i = new Intent(SplashScreen.this,MainActivity.class);         startActivity(i);         finish();      }   And here is the MyThread Class through which i sending message to handler  class MyThread implements Runnable{       @Override     public void run() {          for (int i=0;i<100;i++){              Message message = Message.obtain();              message.arg1 = i;             handler.sendMessage(message);               try {                  Thread.sleep(100);              } catch (InterruptedException e) {                 e.printStackTrace();             }           }     } }//mythread   I want to start my main activity when progressbar complete its progress. but mesage.arg1 returns null Tell me where i am making mistake


On 18.04, package "virtualbox-guest-utils" does not exist

In the past, I've managed to get the virtual box shared folder via the command on trusty and xenial boxes.  $ sudo apt-get install virtualbox-guest-utils   But now on the bionic version - the packages does not even exist yet.  So my question is, how do we share the folder on ubuntu 18.04?


USB flashdrive can't be formated, detected but no disc


Why, specifically, does this binary Fibonacci algorithm have an exponential runtime complexity?

Here is the PDF I will referring to.:    The algorithm I'm referring to (which can also be found in the PDF file, above) is the following.:  public static long fibonacciBad(int n) {     if(n <= 1)         return n;     else         return fibonacciBad(n-2) + fibonacciBad(n-1); }   I'm trying to understand why fibonacciBad is O( 2^(n/2) ), assuming that I'm correct in that being what the PDF is implying.   I suspect that it has to do with using B for every second numbers of calls in A, but the specifics are unclear to me. Also, could someone please give me an intuitive explanation as to why it's okay for it to be every second number of calls in order to be considered exponential (instead of every single number of calls being at least double the previous one)? (I'm making up this alphabetical notation, A and B, for below. This notation isn't used in the PDF linked to here.)  A:  c_0 = 1  c_1 = 1  c_2 = 1 + c_0 + c_1 = 1 + 1 + 1 = 3  c_3 = 1 + c_1 + c_2 = 1+ 1 + 3 = 5  c_4 = 1 + c_2 + c_3 = 1 + 3 + 5 = 9  c_5 = 1 + c_3 + c_4 = 1 + 5 + 9 = 15  c_6 = 1 + c_4 + c_5 = 1 + 9 + 15 = 25  c_7 = 1+ c_5 + c_6 = 1 + 15 + 25 = 41  c_8 = 1 + c_6 + c_7 = 1 + 25 + 41 = 67   B:  1 + 2 + 4 + ... + 2^(n-1) = 2^n - 1


Linux executable fails with "File not found" even though the file is there and in PATH

I want to launch the wine executable (Version 2.12), but I get the following error ($=shell prompt):  $ wine bash: /usr/bin/wine: No such file or directory $ /usr/bin/wine bash: /usr/bin/wine: No such file or directory $ cd /usr/bin $ ./wine bash: ./wine: No such file or directory   However, the file is there:  $ which wine /usr/bin/wine   The executable definitely is there and no dead symlink:  $ stat /usr/bin/wine   File: /usr/bin/wine   Size: 9712            Blocks: 24         IO Block: 4096   regular file Device: 802h/2050d      Inode: 415789      Links: 1 Access: (0755/-rwxr-xr-x)  Uid: (    0/    root)   Gid: (    0/    root) Access: 2017-07-13 13:53:00.000000000 +0200 Modify: 2017-07-08 03:42:45.000000000 +0200 Change: 2017-07-13 13:53:00.817346043 +0200  Birth: -   It is a 32-bit ELF:  $ file /usr/bin/wine /usr/bin/wine: ELF 32-bit LSB executable, Intel 80386, version 1 (SYSV),  dynamically linked, interpreter /lib/ld-linux.so.2, for GNU/Linux 2.6.32,  BuildID[sha1]=eaf6de433d8196e746c95d352e0258fe2b65ae24, stripped   I can get the dynamic section of the executable:  $ readelf -d /usr/bin/wine Dynamic section at offset 0x1efc contains 27 entries:   Tag        Type                         Name/Value  0x00000001 (NEEDED)                     Shared library: [libwine.so.1]  0x00000001 (NEEDED)                     Shared library: [libpthread.so.0]  0x00000001 (NEEDED)                     Shared library: [libc.so.6]  0x0000001d (RUNPATH)                    Library runpath: [$ORIGIN/../lib32]  0x0000000c (INIT)                       0x7c000854  0x0000000d (FINI)                       0x7c000e54  [more addresses without file names]   However, I cannot list the shared object dependencies using ldd:  $ ldd /usr/bin/wine /usr/bin/ldd: line 117: /usr/bin/wine: No such file or directory   strace shows:  execve("/usr/bin/wine", ["wine"], 0x7fff20dc8730 /* 66 vars */) = -1 ENOENT (No such file or directory) fstat(2, {st_mode=S_IFCHR|0620, st_rdev=makedev(136, 4), ...}) = 0 write(2, "strace: exec: No such file or di"..., 40strace: exec: No such file or directory ) = 40 getpid()                                = 23783 exit_group(1)                           = ? +++ exited with 1 +++   Edited to add suggestion by @jww: The problem appears to happen before dynamically linked libraries are requested, because no ld debug messages are generated:  $ LD_DEBUG=all wine bash: /usr/bin/wine: No such file or directory   Even when only printing the possible values of LD_DEBUG, the error occurs instead   $ LD_DEBUG=help wine bash: /usr/bin/wine: No such file or directory   Edited to add suggestion of @Raman Sailopal: The problem seems to lie within the executable, as copying the contents of /usr/bin/wine to another already created file produces the same error  root:bin # cp cat testcmd      root:bin # testcmd --help Usage: testcmd [OPTION]... [FILE]... Concatenate FILE(s) to standard output. [rest of cat help page]  root:bin # dd if=wine of=testcmd   18+1 records in 18+1 records out 9712 bytes (9.7 kB, 9.5 KiB) copied, 0.000404061 s, 24.0 MB/s  root:bin # testcmd bash: /usr/bin/testcmd: No such file or directory   What is the problem or what can I do to find out which file or directory is missing?    uname -a:  Linux laptop 4.11.3-1-ARCH #1 SMP PREEMPT Sun May 28 10:40:17 CEST 2017 x86_64 GNU/Linux


How can I expand a quoted variable to nothing if it's empty?

Say I have a script doing:  some-command "$var1" "$var2" ...   And, in the event that var1 is empty, I'd rather that it be replaced with nothing instead of the empty string, so that the command executed is:  some-command "$var2" ...   and not:  some-command '' "$var2" ...   Is there a simpler way than testing the variable and conditionally including it?  if [ -n "$1" ]; then     some-command "$var1" "$var2" ...     # or some variant using arrays to build the command     # args+=("$var1") else     some-command "$var2" ... fi   Is there a parameter substitution than can expand to nothing in bash, zsh, or the like? I might still want to use globbing in the rest of the arguments, so disabling that and unquoting the variable is not an option.


I have a database in SQLite that I'll be using to store restaurants information for a website.  The website will allow users to insert new restaurants in the dabase (through php).  My question is, given that each row in a table in the database has its id attribute (which is the primary key), how can I know what id should the next item I'm going to store in the database have?  If the last item added to the database has the id 50, then the next restaurant a user tries to add should have the id 51, but how can I have access to this?  Here's my SQLite Restaurant table:  CREATE TABLE Restaurant (   id NUMBER PRIMARY KEY NOT NULL,   name NVARCHAR2(20) NOT NULL,   description NVARCHAR2(20),   address NVARCHAR2(20) NOT NULL,   priceRange NUMBER NOT NULL REFERENCES PriceRange(id) ON DELETE SET NULL ON UPDATE CASCADE );   Thanks in advance!


How can I parse in java specific text from a website? For example if the site has this in their webpage: <meta property='ABC' content="DEF" />. I would like to search for 'ABC' and find 'DEF'. How can I make a function like this? I've got no experience with html, nor parsing information.  Thanks


Closed form for integral of integer powers of Sinc function

(Edit: Thank you Vladimir for providing the references for the closed form value of the integrals. My revised question is then to how to derive this closed form.)     For all $n\in\mathbb{N}^+$, define $\mathcal{I}_n$ by the definite integral,   $$\mathcal{I}_n:=\int_{0}^{\infty}\frac{\sin^n{(x)}}{x^n}\mathrm{d}x.$$   Prove that $\mathcal{I}_n$ has the following closed form:   $$\mathcal{I}_n\stackrel{?}=\pi\,2^{-n}\left(n\sum_{k=0}^{\lfloor\frac{n-1}{2}\rfloor}\frac{(-2)^k(n-2k)^{n-1}}{k!(n-k)!}\right),~~\forall n\in\mathbb{N}^+.$$     Integrals of small positive integer powers of the $\operatorname{sinc}$ function come up on a regular basis here, but it occurred to me that while I probably know the derivations for the $1\le n\le 4$ cases like the back of my hand, I can't recall ever working the integrals wfor any value of $n$ higher than that. The values of the first four integrals are,  $$\mathcal{I}_1=\frac{\pi}{2},\\ \mathcal{I}_2=\frac{\pi}{2},\\ \mathcal{I}_3=\frac{3\pi}{8},\\ \mathcal{I}_4=\frac{\pi}{3}.$$  So I set out to first calculate $\mathcal{I}_5$ to see if any obvious pattern jumped out (and see if the trend of being equal to rational multiples of $\pi$ continued). I wound up getting frustrated and asking WolframAlpha instead. It turns that while the first four cases hinted very much at the possibility of a simple pattern relating the values of $\mathcal{I}_n$ for different positive integers $n$ (or possibly two separate patterns for even and odd $n$), the next few values most definitely did not:  $$\mathcal{I}_5=\frac{115\pi}{384},\\ \mathcal{I}_6=\frac{11\pi}{40},\\ \mathcal{I}_7=\frac{5887\pi}{23040}\\ \mathcal{I}_8=\frac{151\pi}{630}.$$  So my questions are, 1) is there a systematic way to compute these integrals for all $n$?; and 2) is there an elegant way to represent these values in closed form for general $n$?


Let $A, B, C, D$ will be square matrices $n  \times  n$ over $R$.  Suppose that with $AB ^{T}$ and $CD ^{T}$ are symmetrical and $AD ^{T} - BC ^{T} = I$.  Show that: $A ^{T} D - C ^{T} B = I$:  I'm trying to transform the last equation, but it comes to me something like this: $A^{T} C   = C ^{T} A$ I do not know I can prove it. maybe I do it not as it should be, I would ask for any hint.


How to keep up with packages and know which ones are obsolete?

I'm an on and off user of LaTeX so I'm not familiar with every package out there. Having said that, whenever I use LaTeX and need to accomplish a certain goal (i.e. ), I search around and find some kind of solution that involves a package that I didn't know about. I think that's great, I learn something new, and it goes in my template file.  Every now and then, though, my search comes up with a package that, after much wrangling, I find out that it's obsolete. An example of this is just recently I came across the subfigure package and wanted to try it out. Soon after I found out from here that it has become . I usually keep my TeX up-to-date because I like keeping up with new XeLaTeX features.   My question is, is there a map or timeline of what TeX packages should be avoided because there are better ways of doing things? An idea I have is some kind of list of all packages split by what they accomplish, then cancelling out packages whose features are incorporated into and improved upon by newer packages.  Edit: another example is lscape versus pdflscape. The latter implements rotating pages in the final PDF not just for pdftex but also for other drivers such as xetex. The only way I found out about this was Googling latex lscape rotate xelatex, for which the second link leads to the  (PDF).  Great answers so far. I'll check them out and see which one works best for me.  Edit 2: Turns out that my question is a bit of a dupe in the sense that a great answer came up on an unrelated question. The nag package . Gotta try it!


Adding timestamp into log file via cronjob command

I try to run git pull command with loging output message to file every 5 minutes.  But i got error like this,  (root) CMD (cd /var/www/sites/ && git pull origin master | sed -e "s/^/$(date +\") (CRON) error (grandchild #1111 failed with exit status 2)   My cronjob command as follows.  */5 * * * * cd /var/www/site/ && git pull origin master | sed -e "s/^/$(date +\"%d-%m-%y\ %T\"), /" >> /var/log/crond/site.log   How can fix it?


How to connect a SAS expander like RES2SV240?

I'm afraid this is going to be a very noob question, sorry.  I am looking at the  card from Intel. I have never used SAS or an expander, and I'm a bit confused about how it works.  First, the description on their website says the card has 8 SFF-8087 connectors. The picture next to it only shows 6 connectors. Is that a mistake in the description?  Second, and really my main question, how does one connect this up? From other discussions I've read, the PCIe connector is only for power. So if I connect the 6 connectors to 24 HDDs, how do I connect the RAID/JBOD controller? Or do I have to keep at least one SFF-8087 to connect to the controller and therefore be limited to 20 HDDs?


I am new to Ubuntu. I am running 15.10. I'm trying to launch Steam but it doesn't do anything.  I saw that it still runs without showing anything on the screen.  What can I do?


How do I check the battery's status via the terminal?

I would like a command that displays the battery status in the terminal.


If I buy a tube of liquid yeast from my local homebrew store and throw it in the fridge, how long before it's no good?  How 'bout dry yeast?


Why didn't Sauron give the Hobbits any rings?

In the movie The Lord of the Rings it said that Sauron somehow gave (presumably by proxy) several rings to Elves, Dwarves, and Men. There's also another race called Hobbits, who became quite important in the story. Why didn't he give them any rings so that he could control them as well?  Forgive my ignorance here; I never read the books and I'm only watching the movie for the 2nd time in 16 years.


What is the ICM profile and how it is managed in Windows?

I have download the ICM profile for my monitor but Windows XP shows me colors in a way, Firefox and GIMP in another.  So my question is what really is an ICM profile and how Windows and other application software manage it?


Why Doesn't the Ministry Ever Modify the Dursleys' Memories?

Thinking about it while I was writing up my other question about Dudley's pig's tail, it occurred to me that I cannot think of a single instance in which the Dursleys -- Verrnon, Petunia, and Dudley -- had their memories modified, even though they have witnessed numerous incidents of a witch or wizard performing magic.   They witnessed Hagrid giving Dudley the pig's tail. They've witnessed numerous owl post deliveries. They've noticed that wherever they go, or Harry goes, they can always be found. They witness Dobby dropping the pudding on Mrs Mason in CoS (they think Harry did it, though) and of course there's the incident with Aunt Marge. Marge seems to be the only Dursley whose had her memory modified by the Accidential Magic Reversal Squad; meanwhile, the Ministry allows Vernon, Petunia, and Dudley to keep their memories of what happened to Marge. They're allowed to keep their memories of the Dementor attack, and when George, Fred, Ron, and Arthur come to Privet Drive to collect Harry in, I believe, GoF, and one of the twins feeds Dudley Ton-Tongue Taffy and Dudder's tongue grows about six feet long, there is no consequence from the Ministry, it seems. There are plenty of other examples.  Why doesn't the Ministry ever modify the Dursleys' memories?  ★ I don't prefer an answer from the HP Wikia or the Wikipedia.   ETA: I really do get what people are saying about Muggle families with witches in wizards in them, and how they cannot be Obliviated for every little thing. That makes sense now that people have explained it. But I still wonder about Dudley's piggy tail because that would have essentially been introducing a magical pig's tail into the Muggle world via a Muggle hospital, to Muggles doctors who have no familial connection to the Dursleys. Would the Ministry want that happening? It truly surprises me that no one had their memory modified as a result of the pig's tail incident.


I an array like this  @observable data = [{a: 1}, {b: 1}, {c:1}];  @observable sampleData = [];   I want to do a slice   this.sampleData = this.data .slice(0, 1);  this.sampleData[0].a = 2;    I want "2" to effect the the record in "sampleData" not in the "data" array what is happening now.


How to calculate the different combinations of an N×M grid with 3-valid values

I have 3 valid values: a,b,c I can insert them in a N×3 grid in such a way that no row or column contains cells that are the same values. How can I calculate the number of valid patterns that can be created using N rows? For example, if N = 4, the total number of valid pattern is 296490.  This is my attempt: def countPatterns(n):      dp1, dp2 = 6,6     mod = 10 ** 9 + 7          for i in range(2, n+1):         dp1, dp2 = (dp1 * 3 + dp2 * 2) % mod, (dp1 * 2 + dp2 * 2) % mod     return (dp1 + dp2) % mod  When N = 4, the output should be 174 but I'm getting 54.


One of my oracle database columns needs to have the value 'user.password&user.user_name' When I execute the query, I see a popup, because the query has '&user' in it. How do I get around it?  Example query:  update Table A set value = 'user.password&user.user_name' where id = 1;


Is the omission of the verb "To be" in informative sentence

I have the following sentence:  File (is) larger than allowed.  Is the verb "to be" required here?  Is it correct English to use "File larger than allowed."?


my question is about creating objects which inherit from a "superclass".  I came up with a few different ways:  function PersonClass_1() {     this.age = 0;     this.gender = "female"; }  PersonClass_1.prototype.doAge = function () {     this.age++; }  // create a new Object that inherits from Person.prototype var p1 = Object.create(PersonClass_1.prototype);  // Call constructor function, with |this| set to the newly // created object |p1|. PersonClass_1.call(p1);    function PersonClass_2() {}  PersonClass_2.prototype.doAge = function () {     this.age++; }  PersonClass_2.prototype.age = 0; PersonClass_2.prototype.gender = "female";  // create a new Object that inherits from Person.prototype var p2= Object.create(PersonClass_2.prototype);  // Call constructor function, with |this| set to the newly // created object |p2|. PersonClass_2.call(p2);    function PersonClass_3() {     this.age = 0;     this.gender = "female";     this.doAge = function () {         this.age++;     } }  // create a new Object that inherits from Person.prototype var p3 = Object.create(PersonClass_3.prototype);  // Call constructor function, with |this| set to the newly // created object |p3|. PersonClass_3.call(p3);   So what I end up with is three objects. The only difference seems to be the actual location of their attributes.  PersonClass_1 has the age and gender in the object itself, and the doAge in its prototype.  PersonClass_2 has the age, gender and doAge all in its prototype.  PersonClass_3 has the age, gender and doAge all in the object itself.  But the behaviour of the three Persons seems to be all the same. Or is their any major difference?


I came across this equation   $$\sqrt a-\sqrt b=\sqrt 7-\sqrt 5$$  And you have to find the value of '$a$' and '$b$' when both of them are primes. The solution was $a=7, b=5$.  Now, my question is, can't there be any other primes?


On most Stack Exchange sites, when I visit them I am already logged in if I have logged in before. Why isn't it the case with ?


Do I have to repeat a verb before and after "and"?

I am writing an essay and I am stuck with this sentence      The citizens cast their votes choosing Mark as president and choosing me as vice-president.   is this correct or should it be      The citizens cast their votes choosing Mark as president and me as vice-president.


I'm trying to write a document using a .bib as a database of entries, and then formatting them. However, I need to have some entries in multiple languages.  So, is there an easy way to localize fields in a .bib entry, such that I can extend the model.  For example, now I'm using a really straightforward way to change between languages of each entry  \documentclass{article}  \usepackage[utf8]{inputenc} \usepackage[spanish]{babel} \usepackage{filecontents}  \begin{filecontents}{\jobname.dbx} \DeclareDatamodelEntrytypes{localized}  \DeclareDatamodelFields[type=field,datatype=literal]{   description-english,   description-spanish, }  \DeclareDatamodelEntryfields[localized]{   description-english,   description-spanish, } \end{filecontents}  \begin{filecontents}{\jobname.bib} @localized{entry1,   description-english = {this is english},   description-spanish = {esto es español} } \end{filecontents}  \usepackage[datamodel=\jobname]{biblatex} \DeclareFieldFormat{description-spanish}{#1} \DeclareFieldFormat{description-english}{#1} \newbibmacro*{langfield}[1]{%   \expandafter\iffieldundef\expandafter{#1-\languagename}{}{\expandafter\printfield\expandafter{#1-\languagename}}% } \DeclareBibliographyDriver{localized}{%   \usebibmacro{langfield}{description} }  \addbibresource{\jobname.bib}  \nocite{*} \begin{document} \printbibliography \end{document}   However, this becomes really hard to manage if I have several entries that should be in multiple languages, as I need to declare each in the data model. Also, it does not support some spelling changes. For example, if I want to put a university field, in Spanish it is spelled "Universidad X" while in English it should be "X University", or in some cases "University X".   Thus, having a way to default some fields or macros would be useful. Is there something that I can use to achieve such behavior from biblatex?


$R$ is PID, so $R/I$ is PID, and application on $\mathbb{Z}$ and $\mathbb{N}$

I'm supposed to show in a part of an exercise that if we have a ring $R$ that is a principal ideal domain, then for any ideal $I$ in $R$, $R/I$ will also be a PID.  So $I=(i)$ for some $i \in R$, and $R/I$ is $\{rI |r\in R\}$, and we know:   An ideal $J$ in $R/I$ will be an ideal $J$ in $R$ containing $I$.  So if $I \subset J$ and $I=(i)$, then $J$ should be $(j)$, where $j|i$. but wherefrom do I get the necessity that $J=(j)$, so that $J$ is also principal? and there will be several $j$ that divide $i$, but should it not be only one?  And then I shall use this to show a 1-1 correspondence between ideals of $\mathbb{Z}$ and $\mathbb{N}$.  Can someone support with with the proofs?


what is the best practice to create a scheduled task to access a URL?

I have an application deployed on AWS on a linux instance running LAMP. Programming language of choice is PHP.  I have a process or a function that needs to be executed every 30 mins.  What is the best way to achieve this?  In an IIS environment, I would be able to create a scheduled task, but was looking to see if I can get a serverless solution since I am using AWS.  an example is: I have a script that can be accessed via http://. 30 mins goes to  the URL request should respond with a JSON with either success or fail, if fail with proper error.  Any help is appreciated.  Rick


I am currently living in Geneva. I lost my Indian passport with US visa and I am wondering if I should apply for the Visa from Bern or from India. I contacted the Indian consulate and they told me they will get me a new passport in a couple of weeks. Has any body been in this situation before? How did it go?


Sudden decrease in pages crawled per day

During the last few days, Googlebot has crawled much less page in my site than it normally does. I'm not seeing any new errors, and haven't identified a reason for this. Is such a hugh and sudden decrease a sign there is a problem? Can this be just a temporary thing?    Update: The Time spent downloading a page (in milliseconds) graph remained steady.


Transparency of whole image at the position of an object

Is there a material or render setting which makes the whole rendered image transparent at the spot of an object? I.e. not to create only a transparent object where the background is visible, but a transparent „hole“ with Alpha=0? I know that this can be achieved post-rendering by the Compositor and e.g. Cryptomatte, but I would like to define the transparent areas before rendering. Greetings from Germany, Tschöbbel


Why Did Anakin Skywalker Believe that Turning to the Dark Side of the Force Would Save Padmé?

Just as the question asks: Why did Anakin come to believe that Padmé could be saved if he embraced the Dark side of the Force? Padmé clearly didn't believe it. Why was Anakin so driven to save Padmé through the dark side?


Creation and validation of directory using try/except or if else?

This is only a question regarding which one would be more "pythonic"  using if:  import os somepath = 'c:\\somedir' filepath = '%s\\thefile.txt' % somepath if not os.path.exists(somepath) and not os.path.isfile(filepath):     os.makedirs(somepath)     open(filepath, 'a').close else:    print "file and dir allready exists"   or using try/Except:  import os somepath = 'c:\\somedir' filepath = '%s\\thefile.txt' % somepath try:     os.makedirs(somepath) except:     print "dir allready exists" try:     with open(filepath):         // do something except:     print "file doens't exist"   As you can see on the examples above, which one would be more correct on python? Also, On which cases should i use try/except instead if/else ? I mean, should i replace all my if/else tests to try/except?  Thanks in advance.


Can $(\Bbb N,\leq)$ have an $\aleph_0$-categorical theory (in a larger language)?

One of the nicer consequences of compactness is that there is no statement in first-order logic whose content "$\leq$ is a well-order". So we can show that there are countable structure $(M,\leq)$ which are elementarily equivalent to $\Bbb N$, but not isomorphic to it.  What about adding $S,+,\cdot$ and $0$? Well. Also not very good. The theory of the structure $(\Bbb N,0,S,+,\cdot,\leq)$ has $2^{\aleph_0}$ non-isomorphic countable models. This shows that none of these additions get us any closer to finding an $\aleph_0$-categorical theory for $\Bbb N$.     Question. Is there a finite (or countable if needed) first-order language which includes $\leq$, and an $\aleph_0$-categorical theory $T$ whose countable structure is order isomorphic to $(\Bbb N,\leq)$?


Why am I getting NullPointerException for this code?

import ddf.minim.*; AudioPlayer player; Minim minim;  Table t1= new Table(300, 300); float power=0; float dx=0; float dy=0;  void setup() {   size(1000, 600);   frameRate(20);   minim= new Minim(this);   player=minim.loadFile("ballsound.mp3"); }  void draw() {   strokeWeight(1);   stroke(0, 0, 0);    strokeWeight(10);   stroke(255, 0, 0);   fill(26, 218, 35);   rect(0, 0, 1000, 600);   noStroke();   fill(0);   ellipse(0, 0, 80, 80);   ellipse(1000, 0, 80, 80);   ellipse(0, 600, 80, 80);   ellipse(1000, 600, 80, 80);   strokeWeight(1);   stroke(0, 0, 0);   fill(255);   ellipse(t1.cue_ball.center.x, t1.cue_ball.center.y, 20, 20);    t1.cue_ball.center.x+=dx;   t1.cue_ball.center.y+=dy;    dx=friction(dx);   dy=friction(dy);     stroke(40);    strokeWeight(4);   line ( mouseX , mouseY , mouseX + cos (atan2 ( mouseY -t1.cue_ball.center.y , mouseX - t1.cue_ball.center.x) )*300 , mouseY +  sin( atan2 ( mouseY - t1.cue_ball.center.y , mouseX -t1.cue_ball.center.x ))*300);    if (mousePressed)   {     power+=4;    }    if (t1.cue_ball.center.x+20 > 1000 || t1.cue_ball.center.x-20 < 0 )   {      dx*=-1;     player.rewind();     player.play();   }   if (t1.cue_ball.center.y+20 > 600 || t1.cue_ball.center.y-20 < 0)   {     dy*=-1;     player.rewind();     player.play();   }    if( (t1.cue_ball.center.x < 40  && (t1.cue_ball.center.y < 40 ||t1.cue_ball.center.y > 560 ) )  ||  ( t1.cue_ball.center.x > 980 && ( t1.cue_ball.center.y > 580 || t1.cue_ball.center.y < 40)))   {     dx=0;     dy=0;     fill(255);     textSize(25);     text("GAME OVER" ,500,300);     player.pause();   }   if (t1.cue_ball.center.x +20 == 1000)  {    t1.cue_ball.center.x=979;  }  if (t1.cue_ball.center.x -20 == 0)  {     t1.cue_ball.center.x =21;   }  if(t1.cue_ball.center.y -20 == 0)  {    t1.cue_ball.center.y  =21;  }       }    void mouseReleased() {   dx=t1.cue_ball.center.x-mouseX;   dy=t1.cue_ball.center.y-mouseY;   float n= sqrt(pow(dx,2)+pow(dy,2));    dx*=power/n;   dy*=power/n; }  float friction (float c) {   c*=0.9;   return c; }  class Ball  {   float rad;   Point center;   Point contact_point;   color col;    Ball ( float a, float b)   {     center = new Point (a+=dx, b+=dy);   } }   class Table {   Ball [] b_arr;       Stick st;   Ball cue_ball;    Table ( float a, float b )   {      cue_ball= new Ball( a, b);   } }  class Point {   float x;   float y;    Point(float a, float b)   {     x=a;     y=b;   } }  class Stick {   Point start_p;   Point end_p;   color col;   int length; }   Since the stick was added it has stopped being able to bounce off the walls and I can't understand why.  It was working before it was added, and then it just stopped and when it gets close it gives NullPointerException.  I don't see how to stick would change anything though.


While doing a fresh ubuntu install (dual boot with XP using resize), I somehow managed to install grub to the source usb instead of to the harddrive. Normal harddrive boot goes straight to XP. Booting from USB leads me to grub. From there i can boot into ubuntu. Pretty cool actually, but not what I had in mind.  How do I install Grub to HD?   How do I recover my USB?


Assume that $f : A \to A$ is a function such that $\forall x, y \in A,\|f(y)-f(x)\|=\|y-x\|$. Prove that $f(A)= A$

Good morning, I'm trying to solve this problem:        My attempt:  Assume the contrary that there is $z \in A - f(A)$. Because, $f$ is Lipschitz continuous and $A$ is compact, $f(A)$ is compact. As such, $A-f(A)$ is open and thus there is $\mathbb B(z,r) \cap f(A) = \emptyset$.   After that, I'm stuck and unable to proceed. Could you please shed me some light? Thank you so much!


How to add Generic class in Exception class handler?

what i want to achieve is add Generic  in my exception class which is looked like this before : @ResponseStatus(HttpStatus.NOT_MODIFIED) public class ResourceGeneralErrorTest extends RuntimeException {          public ResourceGeneralErrorTest(String message){         super(message);     }  }  and i use it like this : throw new ResourceGeneralError("Some error string " + errorTransDoMsg.toString());  but i only can pass string value inside this class. I want to pass Object class in this, so i try to add this : @ResponseStatus(HttpStatus.NOT_MODIFIED) public class ResourceGeneralErrorTest<T> extends RuntimeException {      private T data;          public ResourceGeneralErrorTest(String message){         super(message);     }  }  which is give me error when i extends the RuntimeException class, here is the error message Generic class may not extend 'java.lang.Throwable' how can i keep extends RuntimeException and i can pass some object into it with my String message?


OEM installation 18.04 personal files lost

I am new to Ubuntu.  I Had installed Ubuntu LTS 18.04 but I went with OEM installation.   At that time after installing Ubuntu I copied some personal files on HDD.   2 Days later I clicked "Ready to be shipped" Icon, now I can’t locate my personal Files on HDD.   It did be kind of you guys to please help me out retrieve my data


Importing photos finds all image files, not just camera pictures

When trying to import photos from my Galaxy S2 in Windows, it tries to import all image files on the phone (including application data), not just those in DCIM.   The system is Android 4.0.3. The phone is set to connect as a camera (but Windows Explorer can still see the full directory structure on the phone and SD card.)


How fast does a black hole appear to decay from infalling observer's perspective?

Black holes eventually decay by emitting radiation. It can take a long time. But from an outsider's perspective.   How long does it take from the perspective of someone falling into it?   I understand that time passes faster for someone closer to it, so would the rate at which it decays also appear to speed up?  Could it be so fast that the person falling into it sees it decay before it even reaches the surface?


How do I suspend a whole process (like the Process Explorer does when I click Suspend) in C#.  I'm starting the Process with Process.Start, and on a certain event, I want to suspend the process to be able to do some investigation on a "snapshot" of it.


Ubuntu 20.04 error on install gimp : Depends: libgimp2.0 (>= 2.10.18) but it is not going to be installed

I have this issue when I search to install Gimp:  $ sudo apt-get install gimp  Reading package lists... Done Building dependency tree        Reading state information... Done Some packages could not be installed. This may mean that you have requested an impossible situation or if you are using the unstable distribution that some required packages have not yet been created or been moved out of Incoming. The following information may help to resolve the situation:  The following packages have unmet dependencies:  gimp : Depends: libgimp2.0 (>= 2.10.18) but it is not going to be installed         Depends: libgimp2.0 (<= 2.10.18-z) but it is not going to be installed         Depends: libgegl-0.4-0 (>= 0.4.22) but it is not going to be installed E: Unable to correct problems, you have held broken packages.   Nothing change after apt update & upgrade. Do you have a solution for me? Thanks to  Best,


Generating random results by weight in PHP?

I know how to generate a random number in PHP but lets say I want a random number between 1-10 but I want more 3,4,5's then 8,9,10's. How is this possible? I would post what I have tried but honestly, I don't even know where to start.


$\lim \limits _{n \to \infty} (3^n+1)^{\frac{1}{n}} = ?$  The help tip says I should use squeeze theorem but somehow still can't figure it out :/


Basically I need to convert centimetres to inches which I am trying to do by diving the area in centimetres by 2.54.   But I just cannot get this to work.   echo "please enter width and then height"  read width read height  area=$(($width * $height)) inchesarea=$((area / 2.54))  echo $area echo $inchesarea   Should I be using bc for this?


How to choose where the software is stored when installing via Ubuntu Software Center

I want to choose where on a hard drive the application is stored when installing it via Ubuntu Software Center. I am not looking for a general setting for all applications, but rather I would like to set the exact folder on hard drive where the currently installed applications will be stored. Also is it a problem to store the application to a NTFS partition?


evaluate $\int_{0}^{\infty}\cos(t) t^{z-1}dt=\Gamma(z)\cos(\frac{\pi z}{2})$

I need to prove $\int_{0}^{\infty}\cos(t) t^{z-1}dt=\Gamma(z)\cos(\frac{\pi z}{2})$ for $0<Re(z)<1$. I tried $\cos t=\frac{e^{it}+e^{-it}}{2}$ and to integrate it along the contour from $\epsilon $ to R, then to $Ri$ via a quarter of a circle, then downward to $\epsilon i$, finally back to $\epsilon$ via a small quarter of a circle. However, I find that $e^{-it}t^{z-1} $ does not converge when $R\to \infty$, can anyone give a correction of my integration or offer another method to evaluate the integral?(would be better if using complex contours) thanks in advance.


Inconsistent text on user's tag badge page and on tag badge tooltip

See these three pages:          All three of them say:     Earned at least X total score for at least 20 answers in the  tag.   This same text also appears on the tooltip for the tag badge:   Also note the double colon after 'gold badge'  As well as on these pages:          But the  clearly states:        Bronze Badge:  You must have a total score of 100 in at least 20 non-community wiki answers to achieve this badge.   Silver Badge: You must have a total score of 400 in at least 80 non-community wiki answers to achieve this badge.   Gold Badge: You must have a total score of 1000 in at least 200 non-community wiki answers to achieve this badge.        Edit:  It has been noted in the comments that other users see different numbers in these pages, but in all cases it appears they see the same number of answers are required for all tag badge description, regardless of the badge's type.


When adding 1 to one variable in a 2d array, it adds one to that position on all the arrays. Can someone explain to me why?

I'm working on this website called codefights.com, and the task given in one of the coding challenges is described in this .  I'm trying to take add 1 to a specific position in a 2d array.  I use the following line to do so: newMatrix[i+1][j] += 1 but when I do that it, for some reason adds 1 to every array inside the array at that same position, not just at the one position I specified (Example below)  I would call the function with this array:   minesweeper([[true,false,false], [false,true,false], [false,false,false]])  def minesweeper(matrix):     rowlen = len(matrix[0])     columnLen = len(matrix)      newMatrix = [[0]*(rowlen+2)] * (columnLen+2) #grid of zeros with padding     truePosArray = []     y = 0     for x in matrix: #calculate the positions of the true instance(s)         try:             truePosArray.append([y+1, x.index(True)+1])         except ValueError:             pass         y += 1     if truePosArray == []:         return [[0]*(rowlen)] * (columnLen)      for y in truePosArray: #run once for every true instance         i = y[0]         j = y[1]         newMatrix[i+1][j] += 1         print(newMatrix)   When I print the first result of newMatrix during the last, the output is: [[0, 1, 0, 0, 0], [0, 1, 0, 0, 0], [0, 1, 0, 0, 0], [0, 1, 0, 0, 0], [0, 1, 0, 0, 0]]  Note: there are a padding of zeros around the array.  Why do you guys think this is happening, when I try to perform a similar action like this:  newMatrix = [[0, 0, 0, 0, 0], [0, 0, 0, 0, 0], [0, 0, 0, 0, 0], [0, 0, 0, 0, 0], [0, 0, 0, 0, 0]]  i = 0 j = 1  newMatrix[i][j] += 1 print(newMatrix)   The output is [[0, 1, 0, 0, 0], [0, 0, 0, 0, 0], [0, 0, 0, 0, 0], [0, 0, 0, 0, 0], [0, 0, 0, 0, 0]]  Can anyone help me understand why this is happening? It has been confusing me for such a long time.   Thanks for your help!


There is this story I read years ago about a world where the wealthy created VR worlds for themselves to live in. These virtual worlds were extremely realistic and the 'masters' of those worlds could essentially live like gods in those worlds. 'Of course' at one point they figure out how to 'upload' their consciousnesses into these virtual worlds leaving behind their physical bodies. Each has his own world and is the only human being in it and some of them do not decide to live a god-like existence whilst others do.   Now the protagonist isn't wealthy and he has this entire story of his own I forgot about entirely (shame on me), but I have been lately 'quoting' concepts from the book, so I would like to properly attribute them (plus I fear I am attributing some things to this story which weren't from this one, so I would love to check).


Admob crashes app with NullPointerException in DeviceMotionService

Our app gets lots of NullPointerExceptions in DeviceMotionService. We don't have a WebView in our app; it seems this is related to the Admob SDK. How can I work around the problem to prevent crashes?  java.lang.NullPointerException at android.webkit.DeviceMotionService$2.run(DeviceMotionService.java:103) at android.os.Handler.handleCallback(Handler.java:605) at android.os.Handler.dispatchMessage(Handler.java:92) at android.os.Looper.loop(Looper.java:137) at android.webkit.WebViewCore$WebCoreThread.run(WebViewCore.java:734) at java.lang.Thread.run(Thread.java:856)   DeviceMotionService.java is part of the Android SDK. This doesn't appear to be something I can fix using the answers at


A "one time pad" can be thought of a Vigenere cipher with

A "One Time Pad" can be thought of a Vigenere cipher with...    An infinitely long key  A secure symmetric key  Multiple ciphertext alphabets  A columnar transposition    I had this question come up today in one of my mid-terms and to be honest it caught me off guard a little, I chose (2) but I'm having doubts and now thinking its (3). I'm pretty sure i'll get a quick response to this because its quite a basic question, this is from an initial test on intro to cryptography and I felt I did pretty well on the rest of the test but this is bugging me.   I know one time pad can have infinite period and can be truly unbreakable but that doesn't mean it has an infinitely long key! (does it). (4) is surely a null consideration which leads me to think its (2) or (3)!


when 7 is degree and when it is radian what will be the behaviour?Is in both the cases it is algebraic over Q or not?


I know how to spawn bots with the command tf_bot_add, but when I spawn the bots, they just stand there. How do I get them moving?


The only idempotent element in $\Bbb Z_{51}$ are $0$ and $1$.

True or False: The only idempotent elements in $\Bbb Z_{51}$ are $0$ and $1$.  Here $\Bbb Z_{51}$ is not an integral domain, but I am guessing that it is tricky so how to approach this problem?


Change the Ubuntu program that runs when a command can't be found

When I type a command not found in a PATH in ubuntu, I get something like this:  $ rdesktop The program 'rdesktop' is currently not installed.  You can install it by typing: sudo apt-get install rdesktop   I believe it's a script that looks up the APT archives and suggest an installation package. I'd like to change it so that it offers me to download it at the press of a 'y'. Two questions:  1) Where is the file located?  2) If I just add the install line in the trivial way, it's going to complain that I'm not a root and will fail (because the rdesktop was ran as a mundane user). How do I make it ask for a password and use it to get root access?


I'm trying to figure out how to assign higher priority to one PPA over another PPA. I had a look on bunch of the answers on this forum but none of them solves my problem.  We have two PPA sources on some of our servers which we stick into separate files in /etc/apt/sources.list.d . Some of these repos provide same packages (in terms of names) but different versions and possibly different binaries. Is there a way how we can PRIORITISE one repo over another ?  I read apt_preferences tutorial but it could not be more obscure and didn't find the answers for my question. Here is the situation. WE have the following sources:  $ ls -l /etc/apt/sources.list.d  total 12 -rw-r--r-- 1 root root 66 Jan  2 16:50 nginx-source.list -rw-r--r-- 1 root root 84 Jan  2 16:49 ruby-ng-experimental-source.list   where nginx-source.list content is:  deb     http://ppa.launchpad.net/nginx/stable/ubuntu precise main   and ruby-ng-experimental-source.list content is:  deb     http://ppa.launchpad.net/brightbox/ruby-ng-experimental/ubuntu precise main   Both of these sources provide nginx-full package of different versions etc. When I list the priorities ruby-ng-experimental-source.list is on top of output hence nginx-full is installed from that repo:  $ apt-cache policy nginx-full                                  nginx-full:   Installed: 1:1.2.3-1~38~precise1   Candidate: 1:1.2.6-1~43~precise1   Version table:      1:1.2.6-1~43~precise1 0         500 http://ppa.launchpad.net/brightbox/ruby-ng-experimental/ubuntu/ precise/main amd64 Packages  *** 1:1.2.3-1~38~precise1 0         100 /var/lib/dpkg/status      1.4.1-1ppa0~precise 0         500 http://ppa.launchpad.net/nginx/stable/ubuntu/ precise/main amd64 Packages      1.1.19-1ubuntu0.1 0         500 http://mirror.rackspace.co.uk/ubuntu/ precise-updates/universe amd64 Packages      1.1.19-1 0         500 http://mirror.rackspace.co.uk/ubuntu/ precise/universe amd64 Packages   How do I prioritize repo listed in nginx-source.list over the one which is on top of the list now ? I tried something like this:  $ cat /etc/apt/preferences Package: nginx-full Pin: origin http://ppa.launchpad.net/nginx/stable/ubuntu Pin-Priority: 1000  Package: nginx-full Pin: origin http://ppa.launchpad.net/brightbox/ruby-ng-experimental/ubuntu Pin-Priority: 100   But that has changed priorities of both sources to the same number - or something like that ? So this has NOT changed the priorities and nginx-full is still being installed form the brightbox PPA  $ apt-cache policy nginx-full   nginx-full:   Installed: 1:1.2.3-1~38~precise1   Candidate: 1:1.2.6-1~43~precise1   Package pin: (not found)   Version table:      1:1.2.6-1~43~precise1 1000         500 http://ppa.launchpad.net/brightbox/ruby-ng-experimental/ubuntu/ precise/main amd64 Packages  *** 1:1.2.3-1~38~precise1 1000         100 /var/lib/dpkg/status      1.4.1-1ppa0~precise 1000         500 http://ppa.launchpad.net/nginx/stable/ubuntu/ precise/main amd64 Packages      1.1.19-1ubuntu0.1 1000         500 http://mirror.rackspace.co.uk/ubuntu/ precise-updates/universe amd64 Packages      1.1.19-1 1000         500 http://mirror.rackspace.co.uk/ubuntu/ precise/universe amd64 Packages   Anyone has any idea how to achieve what I'm trying to do ?


Mongodb Standalone Performs better than Replica Set

I am currently using a standalone mongodb with high read operations. Since replica sets could provide high read performance, I setup a 3 node replica set on 3 vms with read preference as "secondary preferred". However I could not see any performance improvement, in fact the replica set runs a little slower(~2 secs) than the standalone.The configuration is as follows, 4GB of RAM, 7GB of data, 50 GB of hard disk on all 3 vms and for the standalone db and We are using aggregate queries. I would like to know what could be the real reason for the replica sets to function slower compared to the standalone db.


Why is it “Who do you help?,” not “Whom do you help?”?

I happened to watch a lecturer was explaining word order of English in the beginners’ English learning course in NHK’s - Japan’s largest and publicly-owned broadcasting network – educational TV program (aired on July 23rd). He showed four cubes, each of which showing the word, “Who”, “You” “Help” “Do” placed at random, and asked students to put the cubes in the right order:   Right answer: Who Do You Help?   I was comfortable with “Who do you help (speak / give / write, and so on) too, but a question arose:   Is “Whom do you help?” grammatically wrong or, obsolete? If so, why is it wrong, how and around when it became obsolete?  I’ve never seriously thought of such question as the declension of a dative pronoun in interrogative form until I hit upon the above TV scene. Taking advantage of this opportunity, I ventured to post a beginner’s question.


Does serial-downvote-reverse refunding affect the daily cap?

I read , but I don't get it. And  seems to fit better; but ... well, no answers there.   Yesterday, I was victim to some ; so Achievements has a long list of -2 entries for yesterday.  Today, as to be expected, Achievements, shows many +2; all fine.  But what I am wondering: right now I got a daily total of 103; and now I am wondering if all those +2 will count for the daily cap today or not.


If $A$ and $B$ are $n\times n$ complex matrices , then $AB-BA=I$ is impossible.

If $A$ and $B$ are $n\times n$ complex matrices , then $AB-BA=I$ is   impossible   I understand this by any example. But how can one explain it generally?


Trying to identify a fairly old (fifty -sixty years) star ship novel

In this novel humans live in an almost jungle like sealed in environment providing for their needs. A few of the inhabitants begin to question where they are and begin to more carefully explore. Eventually a control deck is discovered and they realize where they are at nearly the exact time of the arrival of the star ship at it's destination. If I remember correctly as the ship enters orbit around a planet, it begins to separate into segments in preparation for some sort of transfer to the planet's surface and the story ends there. There were no references to marital status that I remember tho that should not rule it out. I also remember a possible mention of the size of the surviving travelers having deminished over time tho given how much sci fi I read over the years that fact could be bleeding across from another story but maybe not.


How to trigger a script when the systme is idle for certain time?

As the title mentions, is there any way to trigger a script or start/stop an app when the system has been idle for certain time? Similar to how screen is turned off from power settings etc.


Prove that $k[x,y,z,w]/(xy-zw)$, the coordinate ring of $V(xy-zw) \subset \mathbb{A}^4$, is not a unique factorization domain

I want to show that $k[x,y,z,w]/(xy-zw)$, the coordinate ring of $V(xy-zw)\subset\mathbb{A}^4$, is not a unique factorization domain.    Morally, all we need to do is find some nonzero element that can be written in two distinct ways as a product of irreducible elements, but nothing is coming to mind immediately. Thoughts?


package com.reducer.wc; import java.io.IOException; import java.util.*; import org.apache.hadoop.conf.*; import org.apache.hadoop.fs.*; import org.apache.hadoop.io.*; import org.apache.hadoop.mapreduce.*; import org.apache.hadoop.mapreduce.lib.input.*; import org.apache.hadoop.mapreduce.lib.output.*; import org.apache.hadoop.util.*; public class WordCount extends Configured implements Tool {   public static void main(String args[]) throws Exception {     int res = ToolRunner.run(new WordCount(), args);     System.exit(res);   }   public int run(String[] args) throws Exception {     Path inputPath = new Path(args[0]);     Path outputPath = new Path(args[1]);     Configuration conf = getConf();     Job job = new Job(conf, this.getClass().toString());     FileInputFormat.setInputPaths(job, inputPath);     FileOutputFormat.setOutputPath(job, outputPath);     job.setJobName("WordCount");     job.setJarByClass(WordCount.class);     job.setInputFormatClass(TextInputFormat.class);     job.setOutputFormatClass(TextOutputFormat.class);     job.setMapOutputKeyClass(Text.class);     job.setMapOutputValueClass(IntWritable.class);     job.setOutputKeyClass(Text.class);     job.setOutputValueClass(IntWritable.class);     job.setMapperClass(Map.class);     job.setCombinerClass(Reduce.class);     job.setReducerClass(Reduce.class);     return job.waitForCompletion(true) ? 0 : 1;   }   public static class Map extends Mapper<LongWritable, Text, Text, IntWritable> {     private final static IntWritable one = new IntWritable(1);     private Text word = new Text();     @Override     public void map(LongWritable key, Text value,                     Mapper.Context context) throws IOException, InterruptedException {       String line = value.toString();       StringTokenizer tokenizer = new StringTokenizer(line);       while (tokenizer.hasMoreTokens()) {         word.set(tokenizer.nextToken());         context.write(word, one);       }     }   }   public static class Reduce extends Reducer<Text, IntWritable, Text, IntWritable> {     @Override     public void reduce(Text key, Iterable<IntWritable> values, Context context) throws IOException, InterruptedException {       int sum = 0;       for (IntWritable value : values) {         sum += value.get();       }       context.write(key, new IntWritable(sum));     }   } }   I am running this in eclipse it gives following error !  Exception in thread "main" java.lang.NoClassDefFoundError: org/apache/commons/cli/ParseException     at org.apache.hadoop.util.ToolRunner.run(ToolRunner.java:59)     at org.apache.hadoop.util.ToolRunner.run(ToolRunner.java:79)     at com.reducer.wc.WordCount.main(WordCount.java:17) Caused by: java.lang.ClassNotFoundException: org.apache.commons.cli.ParseException     at java.net.URLClassLoader.findClass(Unknown Source)     at java.lang.ClassLoader.loadClass(Unknown Source)     at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)     at java.lang.ClassLoader.loadClass(Unknown Source)     ... 3 more      What is the actual reason for this error. Do, I have to make the jar   and run it in hadoop to see the output ? or else i can see it in   eclipse. I am using a hadoop plugin in eclipse.   Thanks in advance.


I'd like to rollback a change I made recently in TFS. In Subversion, this was pretty straightforward.  However, it seems to be an incredible headache in TFS: Option 1: Get Prior Version  Manually get prior version of each file Check out for edit Fail - the checkout (in VS2008) forces me to get the latest version  Option 2: Get TFS Power Tools  Download Team Foundation Power Tools Issue rollback command from cmd line Fail - it won't work if there are any other pending changes  Option 3: Manually Undo Changes  manually undo my changes, then commit a new changeset  Question How do I rollback to a previous changeset in TFS?


Is there a tool that can be used for batch checking images for corruptions such as these (in this case, occured due to error while moving file),


How come it always says \tikzlibrary{calc} is missing?

Whenever I put 2 trees onto a document, the system always tells me I am missing \tikzlibrary{calc} on the second tree (I have the same line for both trees) on this line \draw[dashed,rounded corners=10]($(1-1) + (-.2,.25)$)rectangle($(2-2) +(.2,-.25)$); even though I have it right above it.


Is always true that $\partial Y$ is a closed set?

Let $(X, d)$ be a metric space and $Y\subseteq X$.   Is $\partial Y$ always a closed set?


Trying to install hercules, unable to access url for install

I am using Ubuntu 16.04. I am following this guide to install hercules:    This URL gives 403 error (forbidden):


Tricky Curved Hardsurface, suggestions? (mandalorian helmet)

I'm stuck trying to figure out how to model this part of the mandolorian hemlet without sculpting.  any help, tips, references is greatly appreciated!


If Java is pass by value, how does this swap method work?

OK so I understand that Java is pass by value (including for References, it passes the Object by the VALUE of the reference - i.e. the address).  If so then why does the swap(int[] array) method - passing an array of primitives - work?  public class TestArraySwap {      public static void swap(int a, int b) {         int temp =b;         b=a;         a=temp;     }      public static void swap(int[]a) {         int temp = a[1];         a[1]=a[0];         a[0]=temp;     }      public static void main(String[] args) {         //Test Primitive swap         int a=1;         int b=2;         System.out.println("a="+a +" b="+b);         swap(a,b);         System.out.println("a="+a +" b="+b);          //Test array swap         int[] array = new int[2];         array[0]=1;         array[1]=2;         System.out.println("a[0]="+array[0] +" a[1]="+array[1]);         swap(array);         System.out.println("a[0]="+array[0] +" a[1]="+array[1]);     } }   The output is  a=1 b=2 a=1 b=2 a[0]=1 a[1]=2 a[0]=2 a[1]=1   The second swap works - I would expect it not to but perhaps I am missing something?


I'm looking for this really cool music video that involved monsters and kids

The video starts off with two kids a boy and a girl—both are speaking Spanish. They wake up and find that not only are their parents gone but also everyone in their town, so they pack up and try to find people.  I know there's a scene where they destroy a car.  When they're traveling they come across a big furry Totoro-like monster in a cave, and the monster is cool. Then it shows us that there's a bunch of kids and they're all running around having a blast and there's also a bunch of other alien looking monsters, but they must be good 'cause they're not attacking anyone.  And that's all I really remember. I've looked everywhere for it and if you can help it would be awesome.  I watched the video 5 or 6 years ago at least. I don't remember any females singing; I'm pretty sure it was a band of guys. It wasn't heavy metal or anything; it was more like pop. I don't remember much about the actual sound of it to be honest.


I want to process a large XML-File, but when I start my Script I get a      Fatal Error: Allowed Memory Size of *** Bytes Exhausted   Does PHP not clear/override the memory when I start my script again?


What is the error with equating a value in an ArrayList to a String? **The ArrayList is type String**

I am trying to create a quiz type thing for Math 30-1. I just started and have already run into an issue that I have never had before, (or can't remember how to fix it). Below is a piece of the code where the error is happening, however I also have a GitHub repository with the entire file of code, and the specific lines of code that have the error are in the README.txt file.  public static void askQuestion(int question_number) {     getQuestion(question_number);     getReply();     if(input == answer.get(question_number)) {         print("Yay, that is the correct answer!");     } else {         print("Sorry, the correct answer is: " + answer.get(question_number));         print("You put: " + input);      } }   GitHub Link:


How to get available view modes per content type?

I am looking for an function that returns all view modes per content type. I already tried to use mobile_theme_entity_view_mode_alter but this function will return all available view modes for a node entity. What I need are the available view modes per node type...  any suggestions?


My document should be letterpaper and my attachments should be a4paper. I had high hopes for the \newgeometry command from the geometry package, but the documentation says      \newgeometry is almost similar to   \geometry except that \newgeometry   disables all the options specified in   the preamble and skips the   papersize-related options: landscape,   portrait and paper size options (such   as papersize, paper=a4paper and so   forth).   Any help is appreciated!


Upper bound on the number of charts needed to cover a topological manifold

If $M^n$ is a compact topological manifold (not necessarily with additional structure), is there an upper bound on the number of charts needed to cover $M$ ? Does this bound depend on the dimension of $M$ ?  Thanks in advance...  Cheers


Is there a way - using key commands - to select all?  I have a sphere that has some vertices deep inside that only appear when I move the ball, and they are not selected no mater if I use the C or the B select keys.  If I could "select all" the program should be able to get these little rouge vertices that I can not seem to collect when I try either C or B.   Thank you


When I entered the value $$\frac{1}{i}$$ in my calculator, I received the answer as $-i$ whereas I was expecting the answer as $i^{-1}$. Even google calculator shows the same answer (Click  to check it out).  Is there a fault in my calculator or $\frac{1}{i}$ really equals $-i$? If it does then how?


Non-uniqueness of Lagrangian and quantization

As far as I understand, in classical (not quantum) physics the equations of motion are established experimentally (e.g. Newton's three laws and Newton's gravity law, Maxwell's equations). Then sometimes it turns out to be convenient  to rewrite them as Euler-Lagrange equations for suitably chosen Lagrangian $L$. However $L$ is not determined uniquely by the equations of motions, and  may be chosen in any convenient way  without affecting the physical results. The situation changes when one considers the quantum version of the equations. Usually one has to choose a particular form of $L$ and either substitute it to the path integral, or construct a Hamiltonian out of it, guess a quantum version of the Hamiltonian, and substitute into the Schroedinger equation, sometimes using further analogies (e.g. so it worked with the Pauli equation, I think).  In all the literature I know it is never explained how to choose the right $L$ for quantizing a problem. All textbooks just ignore this step. I realize that the final criterion of correctness of a theory is its consistency with experiment, but still I am wondering whether there are more theoretical arguments to choose a specific $L$?


I need to be able to save my data on my Ubuntu on USB

I run Ubuntu on a USB, but it doesn't save my data. Is there a way to save my data?


Polynomial rings in infinitely indeterminants

How can we prove that (the set of all polynomials in infinitely non commutative indeterminants over $k$) is a ring, where $k$ is a ring with unity?   Adding two polynomials is a polynomial, but for commutativity  How can we show the following: $ax_1+bx_2=bx_2+ax_1$ (commutativity of addition) If we have finite number of variable it is easy to prove it, (we take the $n-1$ variables...), but what about the infinite number of variables?  Can someone give me a hint?


Do we really need polynomials (In contrast to polynomial functions)?

In the following I'm going to call   a polynomial expression an element of a suitable algebraic structure (for example a ring, since it has an addition and a multiplication) that has the form $a_{n}x^{n}+\cdots+a_{1}x+a_{0}$, where $x$ is some fixed element of said structure,     a polynomial function a function of the form $x\mapsto a_{n}x^{n}+\cdots+a_{1}x+a_{0}$ (where the same algebraic considerations as above apply) a polynomial an element of the form $a_{n}X^{n}+\cdots+a_{1}X+a_{0}$ with indeterminates $X$ (these can be formalized, if we are in a ring, with strings of $0$s and a $1$).   Note that when we are very rigorous/formal, polynomial expressions and polynomials are something different (although in daily life we often use them synonymously). Polynomial functions and expressions are also different from each other although in this case the relationship is a closer one, since every polynomials expression can be interpreted as a polynomial function evaluated at a certain point (thus "polynomial functions" are something more general than "polynomial expressions").  My question is: Why do we use polynomials ? It seems to me that every piece of mathematics I have encountered so far, one could replace every occurrence of polynomials with polynomial expressions/functions without any major change in the rest of the proof/theorem/definition etc.  The only reasons that I can see to use polynomials are the following two:$$ $$ 1. After one makes the idea precise that one can plug "suitable" elements into polynomials (which may lie a ring containing the ring in which the coefficients live in), one can save time in certain setting, by handling the "plugging of suitable elements into polynomials" more elegantly: For example in case of the theorem of Cayley-Hamilton, which in its "polynomial function" version would look like:  Let $A$ be an $n\times n$ matrix over $K$, whose characteristic polynomial (function) is $x\mapsto a_{n}x^{n}+\cdots+a_{1}x+a_{0}$. Then  $$ a_{n}A^{n}+\cdots+a_{1}A+a_{0}I=0. $$  whereas the "polynomial" version looks more elegant:  Let $A$ be an $n\times n$ matrix over $K$, whose characteristic polynomial is $p_{A}\in K\left[X\right]$. Then  $$ p_{A}\left(A\right)=0. $$ 2. The only thing that polynomials can "do", but algebraic expressions/functions can't, is to be different, when the algebraic expressions/functions are the same (i.e. there's a theorem that tells us that the mapping of polynomials to polynomials expressions/functions isn't injective, if the field is finite). Maybe this small difference makes a big enough difference to consider polynomials after all, but as I said, I haven't encountered any situation in which this difference could manifest itself. (I'm guessing that maybe cryptography or higher number theory really needs polynomials and not just polynomial expressions/functions. Since I don't know anything about these subjects, I would be very happy with an example of a theorem (whose content isn't merely technical as it is the case with the theorem above) involving polynomials, where these absolutely cannot be replaced by polynomial expressions/functions. Conversely I would also be happy with an authoritative statement from someone knowledgeable that indeed we could dispense of polynomials, if we wanted to.)


To reproduce the problem, on a brand new fresh organization I have created two records  insert new List<Account>{     new Account(Name = 'FDD App'),     new Account(Name = 'FDD MatureApp') };   Now, SOQL query select id, name from Account where name like '%app%' returns both records     while SOSL query FIND {*app*} IN ALL FIELDS RETURNING Account (Id, Name) returns only the first record but doesn't return the second record even if I put asterisks around the search term   Why does this happen? Is SOSL Full text search broken in Salesforce and why? Why SOSL fails to find the record with search term in it?  I am not asking about , am I asking how do I find records like "FDD MatureApp" using SOSL. Is this possible to get full text search results to find "FDD MatureApp" record using SOSL by search term "App"?


Adaptation of Regular Bike to Disc brakes

I have a DUNLOP SPORT DS 26 Bike. Here is a similar bike:    I would like to add hydraulic disc brakes at both front and rear.  But the frame or forks do not have anywhere I can mount the Calipers, and the wheels I have are regular ones.   How can I convert my regular wheels to adapt to the Disc brake wheels, and how can I mount the calipers to the frame?


How to remove the last character in the loop

I was trying to remove the last comma in the loop so it wouldn't show the extra comma on the last part. Already tried experimenting bunch of times on the code but it does not work at all.  System.out.println("--Unsorted Array--");   for(int i = 0; i < mergeS.length; i++){     System.out.print(mergeS[i]);     for(int j = 0; j < 1; j+=mergeS[i]-1){       System.out.print(", ");   } }   My expected output is 95, 85, 75, 65, 55 but the actual output is 95, 85, 75, 65, 55,


Adjust vertical alignment of checkmark for obtained badges

This is a view of the badge description and checkmark for a specific badge (say, ):    Here is the same badge description from the :    Could we adjust the vertical alignment of the checkmark in the former display to match that of the second? I suspect adjustments would have to be made for both the checkmark and the badge.   As a side-note: Why would there be a period at the end of the first display, but not the second?


While in an audit, you can't add a comment

Just got to decide if an answer should be deleted. It was only a link, no comments. So I wanted to add a comment explaining why link only answers aren't welcome, and got "This is an audit". This defeats the whole audit process, I could randomly try to add a comment to see if I'm being audited.  Is it that hard just to accept the comment, maybe even allow to edit it, and discard it afterwards? The machinery to do so is surely extant.


Full reinstall of Windows 10 that came with laptop?

I have a Lenovo IdeaPad laptop that came with Windows 10.  It has 4 Gb RAM, which was plenty just a few years ago. But on this machine Windows 10 was pretty slow to start with. Adding a 16Gb flash drive dedicated to ReadyBoost helped matters somewhat.  But now, after half a year of use, it became very slow even with ReadyBoost - so slow even YouTube videos can stutter. I did install Avast which does not detect anything, so I don't think it's malware. It is probably the usual "Windows rot", which I am familiar with since Windows 9x and which requires a fresh reinstall. Yes, half a year is a bit too soon - Windows tended to last over a year until it rotted like that. Perhaps it's those huge updates...  Anyway - HOW can I do that fresh reinstall thing if no installation media came with the device?  An alternative would be installing Windows 7 and I even have some OEM packs, but I'm not sure I can find Windows 7 drivers for everything on the machine, including the touch screen, etc. Also, I wonder if Windows 7 will keep working in "tablet mode" which this thing has.  (Another alternative is Linux and it is seriously being considered but I am asking here so I can look at WIndows options. Also not sure about "tablet mode" on Linux).


Book about a boy that controls plants by whistling?

I am trying to remember the name of a fiction book about a boy that could manipulate plants just by whistling.  I think it's a bit of an older book, but I can't seem to find it by searching for those terms.  If it helps at all I think the title had something about green in it, but I can't be certain.  Does anyone have any idea what it is?  I seem to recall that the book was probably close to 20 years old when I read it and that was nearly 10-12 years ago.  The boy first realized he could manipulate plants by using a toy whistle and moved on to being able to make the noises to control the plants with his tongue.  I remember that there was some kind of conflict with bad people and he used his ability to fight them and I think it was in a jungle. I think he made one of the bad guys bite off his own tongue by hitting him with a vine.  It was in English and a soft cover I believe.


What I don not understand is why Java allows this  Generic<Integer> lonelyObject=new Generic<Integer>();  and not this:   Genericd<Integer>[] arrayObject= Generics<Integer>[10];   If the second one looses type safety due to invariance, shouldn't the first be the same?  Thanks for all the replies! I understand why it does not allow arrays to be created, because they contain type info at runtime and due to type erasure there are none for Generics at runtime, but how does this violates type safety and creating a simple object doesn't?  Could somebody please explain.


How do I autohide the top panel in Unity?

When windows are not maximized, the top panel is basically wasted space for me in Unity.  Is there a way to make it autohide? i.e. make it appear on mouse over.


Evaluate$\int_0^1 \frac{x^{m-1} + x^{n-1}}{(1+x)^{m+n}}dx$ in terms of Beta function

I have no idea of Beta functions. Based on some properties of beta functions like, $B(m,n) = \int_{0}^\infty \frac{x^{m-1}}{(1+x)^{m+n}}dx \;\; ;B(m,n) = B(n,m)$  I arrived at $2B(m,n) = I+ \int_{1}^\infty \frac{x^{m-1}+x^{n-1}}{(1+x)^{m+n}}$ where I is my required integral. How to express the 2nd integral in terms of Beta function or is there any other way of solving. Need help. Thank You.


How do I respawn the Ender Dragon when not running a server?

When my brother and I were playing on LAN for one of my worlds we defeated the ender dragon and wanted to refight it. I looked at a few online helps but they only tell me how to do it on a server.


eth0: ERROR while getting interface flags: No such device

I set up CentOS yet.   it's no network connection. eth0 is not device list.   I take a message network is unreachable while ping 192.168.0.1    How can I do reachable network?


Efficient maths algorithm to calculate intersections

For a game I am developing I need an algorithm that can calculate intersections. I have solved the problem, but the way I have done it is really nasty and I am hoping someone here might have a more elegant solution.  A pair of points represent the end points of a line drawn between them. Given two pairs of points, do the drawn lines intersect, and if so, at what point?   So for example call the lines (A.x, A.y)-(B.x, B.y) and (C.x, C.y)-(D.x, D.y)  Can anyone think of a solution? A solution in any language will do.  Edit: A point I should have made clearer, the algorithm must return false if the point of intersection is beyond the lengths of the line segments.


Getting full URL of action in ASP.NET MVC

Is there a built-in way of getting the full URL of an action?  I am looking for something like GetFullUrl("Action", "Controller") that would return something like http://www.fred.com/Controller/Action.  The reason I am looking for this is to avoid hardcoding URLs in automated emails that are generated so that the URLs can always be generated relative to the current location of the site.


How do spacecraft gain kinetic energy by passing near planets?

When a a spacecraft like Voyager travels close to Jupiter, it somehow gains kinetic energy. I'm not sure how this energy isn't simply lost again as it moves away from Jupiter. I'm also hoping this will explain how stars can be ejected from galaxies!


Arthur C. Clarke story about a matrioshka brain

Arthur C. Clarke wrote a short story about a huge matrioshka brain that sends out probes to the far reaches of the Universe to find out more information.  I cannot recall the title, and was hoping someone else knew.


Just want to set viewport to wireframe from script

Not sure how best to do this...  I have a very simple question. When I click on the solid view icon in the window I see the console shows:  bpy.context.space_data.shading.type = 'WIREFRAME'   But when I add that to the Text Script window:  import bpy bpy.context.space_data.shading.type = 'WIREFRAME'   It of course doesn’t run because it doesn’t have the proper context. I also tried:  import bpy  prev_type = bpy.context.area.type bpy.context.area.type = 'VIEW_3D' bpy.context.space_data.shading.type = 'SOLID' bpy.context.area.type = prev_type   which doesn’t throw an error, but doesn’t work either. I know it must be something simple, but how to fix this? Thanks!


I am quite interested in learning topology from the basics, I would like to find a book that is quite detailed and has a large number of examples. What are the best books to easily understand topology? Thanks.


How to set class weights for imbalanced classes in Keras?

I know that there is a possibility in Keras with the class_weights parameter dictionary at fitting, but I couldn't find any example. Would somebody so kind to provide one?  By the way, in this case the appropriate praxis is simply to weight up the minority class proportionally to its underrepresentation?


How to use PC internet in to android phone using usb cable

I want to use my PC broad band Internet in my android device using USB cable because my pc has not any Fifi or blue-tooth so I want to connect with standard USB cable and Used my pc Internet. if any suggestion then let me know.


Face loop select options. Selecting faces between two faces

When I clicked Alt and select the face its select all the faces in the horizontal direction , which is not not what I required I want to select the faces in the vertical direction. Is there anyway to do it. In other software I can shift select two faces and the faces in between automatically gets selected. How can it be done in Blender?


Sum indices besides the sign in math mode?

How can I get the indices of a sum sign to appear besides the sum in math mode?  I know that this is default for inline mode, how can I set this for math mode locally (preferably w/o additional packages etc.)?


There is a mashine called "BIE" visible in my network surrounding of my dolphin File manager (Ubuntu 14.10).  I cannot access that device in dolphin and also don't get an answer pinging it.  How can I find out the IP of that device to do an intense scan with nmap?


What is the minimal possible length of an $n$-universal word?

Suppose $A$ is a finite alphabet. Let's call a word $w \in A^*$ $n$ -universal iff it contains every word from $A^n$ as a subword. What is the minimal possible length of an $n$-universal word over $A$? $|A| = m$.  It is definitely $\geq m^n + n - 1$ , because a word of length $m \geq n$ has $m - n + 1$ subwords of length $n$.   I think, that $|A|^n + n - 1$ is quite likely to be the exact answer, but do not know how to prove it.   It holds, however, for the following particular cases:  $m = 1$: $a^n$  $n = 2, m = 2$: $abbaa$  $n = 3, m = 2$: $abbbaaabab$  $n = 2, m = 3$: $ccacaabbcba$


PHP PDO statement with named parameters and bindParam is not working

This seems so stupid.  This works:  $db = "nameone"; $coll = "utf8_bin"; $sth = $this->dbh->prepare("CREATE DATABASE $db COLLATE $coll"); $sth->execute();   But this gives the following errors: $sth->errorInfo[0] => 42000. $sth->errorInfo[2] => You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near ''nametwo' COLLATE 'utf8_bin'' at line 1.  $db = "nametwo"; $coll = "utf8_bin"; $sth = $this->dbh->prepare('CREATE DATABASE :db COLLATE :coll'); // Changing to double quotes does not matter. Get same error. $sth->bindParam(':db', $db); $sth->bindParam(':coll', $coll); $sth->execute();   What am I missing that would cause the second code with the named parameters and bindParam to error like that. Please note that I'm using database name and collation type, not table name and column name, and that the errors are syntax related. Is there a module that needs to be enabled in php.ini?  Thanks,  Steve


Extruding the camera block for my phone model

I want to do in my 3D model a bulging camera block. Of course, I know this can be done using the "extrude" tool. But I can't use subdivide modifier, consequently I can't do that. And I want to do a "notches" (It's Google Translate, not me) for power button (like power button in Moto Inc. Smartphones)      So, I hope you understand me, because I'm not good in english. Please, don't throw tomatoes at me :) And remember, I don't want to steal someone's design of smartphone, I'm just learning to do something like this.   This is my .blend file:


How come the Tesseract was with Von Strucker?

If the Tesseract was in Asgard after the Avengers (Thor took it along with Loki) how come Von Strucker had it at the end of Captain America: The Winter Soldier? Even more at the end of Thor: The Dark World they said that they took the Aether to the Collector since they already had the Tesseract in Asgard. And didn’t want to Infinity Stones be together.


Getting data from text box and converting to byte array in specified format

How can I convert an input if 16 characters to a byte array with the following format. E.g. From textBox.Text = 4a4de6878247d37b    to      byte[] esk_bytearr = { 0x4a, 0x4d, 0xe6, 0x87, 0x82, 0x47, 0xd3, 0x7b };   The method I'm using is not working and is the below.  static byte[] GetBytes(string str) {     byte[] bytes = new byte[str.Length * sizeof(char)];     System.Buffer.BlockCopy(str.ToCharArray(), 0, bytes, 0, bytes.Length);     return bytes; }   The byte array is an input to an decryption method using DES. The method is working but the decrypted message is different from when I use directly the esk_bytearr directly as parameter to decryption method. Thanks