I am trying to work with lists of objects that all come from the same base class.  I have my base type (question) and derived types (3TQ, 2TQ)  Depending on the situation the list will all be of one or other derived type.  So all my interfaces deal with a list of the base type question.  But once I have the list in my grasp, I cant access the derived types.  So long story short - how does one extract a usable derived object from the list of the base objects?  I feel this should be easy and that I am missing something really obvious.

In C#, what is the best way to access a property of the derived class when the generic list contains just the base class.  public class ClassA : BaseClass {    public object PropertyA { get; set; } }  public class ClassB: BaseClass {     public object PropertyB { get; set; } }  public class BaseClass { }  public void Main {     List<BaseClass> MyList = new List<BaseClass>();     ClassA a = new ClassA();     ClassB b = new ClassB();      MyList.Add(a);     MyList.Add(b);      for(int i = 0; i < MyList.Count; i++)     {         //I would like to access PropertyA abd PropertyB from the derived classes             } }


I'd like to mention that this is not the first time that I've encountered this.  The issue is that if I attempt to review a low quality post that I've flagged earlier, I will not be available to review it unless I press "Looks OK", which makes no sense. If I click "Recommend Close", it simply says that I've already flagged it, as shown in this screenshot:    In the first post reviews, if I've already upvoted/commented/flagged on a post, I will be available to press on "I'm Done", which should also be possible in the low quality post reviews.

I just discovered that it is possible to get a post in the Low Quality Posts review queue that you have already flagged for closing, making reviewing that item impossible. Obviously, I don't want to 'Looks Good' something that I know should be closed, but at the same time I cannot 'Recommend Close' something I have already flagged leaving the only option being to skip the post.  Can the queue be changed so that it does not show posts which you have already flagged?


Prove the following product formulas for separability and inseparability degree: If $F\subseteq L\subseteq K$ are fields, then show that $[K : F]_s = [K: L]_s[L: F]_s$ and $[K: F]_i = [K: L]_i[L: F]_i$  This question has already been posted twice here   , and here  , but in one they do not answer and in another I do not understand the answer because they use another definition for this grade. I am following another book and in that book they define it in the following way:  Let $K$ be a finite extension of $F$. If $S$ and $I$ are the separable and purely inseparable closures of $F$ in $K$, respectively, we define the separable degree $[K : F]_s$ of $K/ F$ to be $[S : F]$ and the insepaTable degree $[K : F]_i$ to be $[K : S]$. With these definitions, we see that $[K: F]_s[K : F]_i = [K : F]$.  I then have that $[K: L]_s[L: F]_s=[S_1:L][S_2:F]$ where $S_1$ and $S_2$ are the separable closure of $L$ in $K$ and $F$ in $L$ respectively, how can I relate this to $[K:F]_s=[S:F]$?

This is a problem from Patrick Morandi's Field and Galois Theory: Chapter I.4, exercise 15.  Let $K$ be a finite extension of $F$. If $S=\{x\in K \mid x \text{ is separable over } F \}$ and $I=\{x\in K \mid x \text{ is purely inseparable over } F \}$ are the separable and purely inseparable closures of $F$ in $K$, respectively, we define the separable degree $[K:F]_s = [S:F]$ and the purely inseparable degree $[K:F]_i = [K:S]$.   Now using these definitions,     Prove the following product formulas for separability and inseparability degree: If $F \subseteq L \subseteq K$ are fields, then show that $[K:F]_s = [K:L]_s [L:F]_s$ and $[K:F]_i = [K:L]_i [L:F]_i$.   Proving just one of the equality will be enough (thanks to Tower law and the property that $[K:F]_s [K:F]_i = [K:F]$).  I started proving:   $[K:F]_s=[K:L]_s[L:F]_s$. Suppose $[K:L]_s=[S_1:F]$ and $[L:F]_s=[S_2:F]$ where $S_1$ and $S_2$ are separable closures of $K/L$ and $L/F$ respectively. And if we take $\{a_i \mid i=1,\dots,m\}$ and $\{b_i \mid i=1,\dots,n\}$ are the basis of $K/L$ and $L/F$ respectively. Is it true that $\{a_ib_j \mid i=1,\dots,m, j=1,\dots,n\}$ is a basis of $S/F$? Then for $x \in S$ how do we proceed?


I'm a little bit confused over the difference between the following sentences.   I went home. I went to home.  Could someone please explain the difference.

Why is this sentence wrong?     He went to home.   is it correct in this way?     He went home


Inspired by the question   I understand the simple out of universe answer is likely "they hadn't come up with the ideas of the newer models yet". But I was wondering if there was some official in universe answer to explain why this would be. Would it not have been better for Skynet to send back a T-1000 first? Maybe a T-X or something? Surely they would have succeeded without Arnold to stop them.    My best guess is that the T-800 was more easily accessible in the shortest amount of time possible, as I imagine Skynet had to rush to use the time machine as quickly as possible once the Resistance had basically won. But is this addressed at any point?

I have seen only the first three movies, so I don't know whether the other movies/TV series deal with this question or not. My main point is that in the movies, the terminator that travels back furthest in time is of the worst quality, and the quality increases with the time travel (meaning they travelled from a later time). What is a good explanation for this?  Note: I am not interested in the obvious not-in-universe explanation that they wanted something better and bigger for each new movie.


I came up a problem with for one of the question. I have to proof if the following statement is true/false.  $$C\setminus(A\setminus B) = (C\setminus A)\cup(C\cap B)$$  I am a little confuse $C\setminus(A\setminus B)$. I am not sure where to start.   Thanks guys.

Show that  $A \setminus ( B \setminus C ) \equiv ( A \setminus B) \cup ( A \cap C )$  This is an exercise I was trying to do ( not homework ) and I got stuck as follows:  Working from $A \setminus ( B \setminus C )$:  $x \in A \wedge x \notin ( B \setminus C )$ $x \in A \wedge ((x \in B \wedge x \in C) \vee (x \notin B \wedge x \in C) \vee (x \notin B \wedge x \notin C) )$  At this point I'm not sure how to proceed.  Working from the other side $ ( A \setminus B) \cup ( A \cap C ) $:  $ x \in ( A \setminus B) \cup ( A \cap C ) $  $ x \in ( A \setminus B) \vee x \in ( A \cap C ) $  $ ( x \in A \wedge x \notin B ) \vee ( x \in A \wedge x \notin C ) $  $ x \in A \wedge (x \notin B \vee x \notin C ) $  $ x \in A \wedge x \notin ( B \cap C ) $  $ A \setminus ( B \cap C ) $  I could also use some formating tips like how display logical not and how to get the lines to display properly without blank lines inbetween. :-)


Niman seems to be the most Force centric style but I believe that it's lacking in both offense and defense, and it doesn't have a good record either, most of Niman's specialists died on the first battle of Geonosis.

I heard that most of the Niman specialists on the first Battle of Geonosis died in the arena. Why is it that they couldn't  train more? Apparently it's idea is to have everything in moderation. If one trained enough, then the form could probably turn from good at everything to awesome at everything. You might not have as much precision as Makashi, or speed as Ataru, etc., but you'd have no apparent or major weaknesses and a very well rounded strength.


According to p. 881 of the TikZ & PGF manual for version 3.0.1a, the following LaTeX manuscript:  \documentclass{article} \usepackage{pgfkeys} \begin{document}     \pgfkeysdefargs{/my key}{#1+#2}{\def\a{#1}\def\b{#2}}     \pgfkeys{/my key=hello+world}     |\a| is \a, |\b| is \b. \end{document}   should typeset as follows (sans background color):    In other words, it appears the vertical bars serve as verbatim. (This is not the first time that I come across this usage. So far I've ignored it whenever I came across it, but I feel now's a good time to get to the bottom of it.)  However, when I compile this manuscript with pdflatex, the body of the resulting PDF document looks like this:    Why aren't the vertical bars recognized as verbatim markers? And why do they show up as dashes?    This is not a duplicate of . This is not about the font but about the fact that the vertical bar is not interpreted as verbatim.

When I try to use one of the more "hacky" methods of getting a literal "special character" (such as backslash or a brace) then I get a different character: backslash seems to be an open quote, left brace a dash, and right brace a close quote.  What happened to my special characters?  \documentclass{minimal}  \begin{document}  \char`\\ \char`\{ \char`\}  \end{document}   produces: "-" (only the two "s are different).


I was reading this script someone wrotte and there is this line:  comm -23 <(grep cat access.log) cats | mailx -s subject address@gmail.com  I understand it to mean convert this output as if it was a file but I just don't understand this syntax and I haven't seen it anywhere else.   Does this mean, execute grep in a sub shell and pipe the output back?

I was wondering how to understand the following:     Piping the stdout of a command into the stdin of another is a powerful   technique. But, what if you need to pipe the stdout of multiple   commands? This is where process substitution comes in.   In other words, can process substitution  do whatever pipe can do?   What can process substitution do, but pipe cannot?


Background  I want to pass a list of filenames (listed via find) containing spaces to my custom python script. Therefore, I set up find to add quotes around each result:  find ./testdata -type f  -printf "\"%p\" "  Result:  "./testdata/export (1).csv" "./testdata/export (2).csv" "./testdata/export (3).csv"   For the sake of this question, let's suppose my custom script (test.py) does the following:  #!/usr/bin/python3 import sys    print(sys.argv)   Observations  Case 1:  Manually listing the quoted arguments.  Input: ./test.py "./testdata/export (1).csv" "./testdata/export (2).csv" "./testdata/export (3).csv"  Output: ['./test.py', './testdata/export (1).csv', './testdata/export (2).csv', './testdata/export (3).csv']  Case 2:  Using xargs  Input: find ./testdata -type f  -printf "\"%p\" " | xargs ./test.py  Output: ['./test.py', './testdata/export (1).csv', './testdata/export (2).csv', './testdata/export (3).csv']  (I.e., output is the same as case 1)  Case 3:  Using backticks.  Input: ./test.py `find ./testdata -type f  -printf "\"%p\" "`  Output: ['./test.py', '"./testdata/export', '(1).csv"', '"./testdata/export', '(2).csv"', '"./testdata/export', '(3).csv"']  Two things have changed:   "./testdata/export and (1).csv" are now two separate arguments. the quotes remained part of the arguments   Questions   Why does the version with backticks behave differently? Is there a way to still include the quotes with the backticks? I.e., make them behave the same as with xargs?   Remark  I really can't imagine what is going on here. One logical explanation could have been, that the output of the command in backticks will be treated as one big argument. But then, why is it splitted at the white spaces?  So the next best explanation seems to be that every white-space separated string is treated as a separate argument, without any regards to quoting. Is this correct? And if so, why do backticks have this strange behaviour? I guess this is not what we would want most of the time...

I want to pipe file names to other programs, but they all choke when the names contain spaces.  Let's say I have a file called.  foo bar   How can I get find to return the correct name?  Obviously I want:  foo\ bar   or:  "foo bar"   EDIT: I don't want to go through xargs, I want to get a correctly formatted string out of find so that I can pipe the string of file names directly to another program.


Let's say I have $n$ fair (six-sided) dice ($n>=6$) and I want to figure out the probability of getting each side at least once. I figured out a formula through elementary combinatorial reasoning: $$\frac{6!\cdot\binom{n}{6}\cdot6^{n-6}}{6^n}$$  First, of all, is this formula correct?  Second, somewhere I read that I could do this with the sieve formula. How do I use the sieve formula for this one?

Possible Duplicate:             Im pretty new to the stackexchange, and posted this is statistics, and then discovered this site, and thought it was much more appropriate, so here I go again:  It is fairly easy to figure out what is the average rolls it would take to roll all faces of a die [1 + 6/5 + 6/4 + 6/3 + 6/2 + 6/1 = 14.7], but that got me thinking of a seemingly more complicated problem.  Say you roll a die 1-5 times, the is the odds of ALL faces showing, is obviously 0. If you roll a die 6 times, the odds of all faces showing can easily be calculated like so:  1 * (5/6) * (4/6) * (3/6) * (2/6) * (1/6) = .0154 or 1.54%  Now is where I get stuck. How to do 7, or more times, and calculate it with n.  Any tips is helpful!


Example:  \begin{equation}     \lor_{j=1}^n \end{equation}   shows up like    and  \begin{equation}     \sum_{j=1}^n \end{equation}   shows up like    Is there a way to make the \lor look like the \sum symbol with its limits?

I know what my symbol or character looks like, but I don't know what the command is or which math alphabet it came from. How do I go about finding this out?


I am currently following a tutorial that asked to open a file with "sudo vi /..." first and formost I have half an understanding of how to type but I managed and now I need to save the file but how do I do that? I tried to use ctrl x but that doesnt work and there is no other means in the file/ edit section of the terminal. Please help.  kind regards coolxm

I can't save changes after editing   sudo vi /etc/network/interfaces   Text before editing:    auto lo iface lo inet ...   Edited to:  auto eth0 iface eth0 inet dhcp   What key combination or sequence must I press to save this?


Look  to see what I mean? Should I ask one of these guys to delete their answer (and merge whatever detail is missing into the other answer)? I'm aware of this , but it's a little different.

Duplicate questions are "solved" — it's clear what to do with them, there're tools to deal with them... but what happens when two users post the same answer? This happens a fair bit, particularly on questions with simple answers ("Click this button"-type ones).  Do we upvote both answers, since they are both correct? Do we upvote the first one (although if the answers were posted within a few minutes of each other, after an hour it's impossible to tell as they both show up as "answered 1 hour ago")? Do we upvote the currently highest voted one? Do we upvote one and downvote the other? Do we flag one (seems a little excessive)? Something else?


Show that $(n!)^2>n^n$ for $n \in \Bbb Z_+$. I tried induction but I was getting stuck in the last step. Please help.  Hints only, please.

Show that if $n>2$, then $(n!)^2>n^n$.     My work: I tried to apply induction. So, at the induction step, I need to prove, $n^n>(n+1)^{n-1}$ Here, I tried to use induction again without any luck. I also took log of both sides, but I did not get anything. Please help!


I am roaming between several access points.  How do I know to which of them I am connected at any given moment?  Command line way is preferred.

I'm reposting  I asked on the  SE, bacause I have been redirected to Super User.  I have successfully set up two Linksys routers running DD-WRTv24 to do WDS. They have the same SSID, but different static local IP addresses. There is no security: it's just for testing; no Internet connection.   When I open my notebook, I see the SSID shared by the routers in the list of WiFi access points, and I can connect to it. Once connected, I can ping both routers' local IP addresses, so I know that the WDS is working. But I can't find a way to find out which of them I have actually connected to.  I wouldn't like to have different SSIDs, because I plan to have the access points hand-off users to one another, and I want it to be transparent for the users. I configured one AP to distribute DHCP IP addresses in one range, and the other in another range, so I can discover which AP I connected to at first, but I want a way to discover which AP I'm connected to now, so that I can find out whether the hand-off actually occurred.


I’m troubleshooting a standard user’s account. She has forgot her password and I’m trying to change the password but there’s no options   My method was   Home > Control Panel > User Accounts > User Accounts (Change account type) > person’s name Account > Change account password  But Change account password is not available. Is there any other way to change the person’s password that I’m troubleshooting in order to get her stuff back?

I got a brand new Windows 7 machine, installed the operating system, created one account and forgot its password. What can I do?  There is no external CD, the operating system is loaded from somewhere inside the machine.  I already tried to remember passwords and tried all candidates with all possible combinations of caps lock, num lock etc.


Each agar.io run awards experience. I know of a few things that grant XP:  Time survived Acquiring mass Number of splits Position on the leader board  But what are the precise numbers? Are there any more factors?

I've been playing Agar for some time now, and lately I've noticed there was a new XP system in Agar. Since then I've been wondering what variables chance the XP gained. I've tried googling it, but with no luck.  I'm looking for how the XP system works in these game modes:   FFA Teams Experimental


Yesterday I posted about wanting to leave my PhD and I've definitely decided that it's the healthiest choice for me. Now comes the hardest part- telling them that I plan to leave the program once I find an alternative role. I'm not a very confrontational person and I hate to feel that I am wasting anyone's time so I want to be as polite and direct as I can be. Is it as simple as emailing to say that I wish to discuss my progress and long term goals and then inform them during the meeting that I've been offered a job?

When needing to ask a professor about something important and potentially delicate, what is an appropriate way to phrase the question or write the email?  Examples include:   Requesting a recommendation letter Asking for exceptions to policy (e.g., ignoring a course prerequisite, rescheduling an exam) Asking if you can do research with them, join a group, get into a program Scheduling a meeting, exam, or defense Letting them know about a change of plans Letting them know about a life event affecting your work or studies (e.g., wedding, funeral, sickness, vacation)


I have seen a restaurant that has chili pepper in the olive oil bottle, it gave the oil a delicious chilli taste. I am planning to do the same at home.   I wonder how to choose the chilli I will be using. What difference do the different types (jalapeno, red chilli, etc.) have on the finished product?  I am aware of the safety issues as discussed in , they are not part of the question.

I am making chilli oil using light olive oil, crushed chilli, dried garlic, dried fennel seeds and parsley.  I have been making this for years. I am concerned about this Botulinum business. Should I be concerned? And what can i do to avoid this?  Currently, I heat the olive oil before putting it into the mixture, jar it, and normally keep it in the cupboard for months, with no problems with taste.  Another thing I am wondering is, how does one measure the expiry date on homemade chilli oil? Can someone help?


I've created a cylinder object which is fine at first. But as modeling goes by I've decided to change some properties,like number of vertices, of the cylinder just to see it in real-time. But cannot find the solution. Search the internet only come up as using "Adjust Last operation". I know I can just add new one. But for the sake of knowledge and future work flow. Thanks in advance.

When you first add a cylinder, you have the option to change the number of vertices, etc, but once you do anything else in blender, it seems you no longer can edit those parameters.   Is there a setting anywhere or an add-on that allows these parameters to be edited later on? If not, how easy would such an addon/feature be to create for anyone reading this?


What is the role of "*" inside of a print function in Python?  print ("Hello World!\n") print (*"Hello World!\n")   Output of the first print function is   Hello World!   Output of the second function is    H e l l o   W o r l d !    But in python 2.7 it does not work!

Does * have a special meaning in Python as it does in C? I saw a function like this in the Python Cookbook:  def get(self, *a, **kw)   Would you please explain it to me or point out where I can find an answer (Google interprets the * as wild card character and thus I cannot find a satisfactory answer).


I'm trying to open a page, and the function does not return. When I click on the button, the function works, but the render_template does not happen and I remain on the previous page

I have an HTML page with a typical structure:  <html>   <head>    <script src="..." ></script>    <style>...</style>   </head>   <body>    content   </body>   <script>     var success_callback = function(data) {       // REPLACE PAGE CONTENT & STRUCTURE WITH "data"     }     ajax(url, params, success_callback);   </script> </html>   Do you think it is possible ?  I've already tried to give the html tag an id and doing $(id).replace(data); with no success.  Don't ask me why, but that is what I need (I'm working with a special "mashup builder" site... it is a long story).  EDIT : I forgot to say that scripts in the received content have to be executed, even external scripts included using <script src="...">.


I just noticed this    How does that come?    The question was spam. Though I'm wondering how I could see these stats? A caching issue maybe?

Two close votes and only one person has viewed the question?    How did this happen?


I ran into some troubles when creating a list of 3 lists. Here is the code:  >>> li = [[]]*3 >>> li [[], [], []] >>> li[0].append(1) >>> li [[1], [1], [1]]   Why is the result not [[1], [], []]?

I needed to create a list of lists in Python, so I typed the following: my_list = [[1] * 4] * 3  The list looked like this: [[1, 1, 1, 1], [1, 1, 1, 1], [1, 1, 1, 1]]    Then I changed one of the innermost values: my_list[0][0] = 5  Now my list looks like this: [[5, 1, 1, 1], [5, 1, 1, 1], [5, 1, 1, 1]]    which is not what I wanted or expected. Can someone please explain what's going on, and how to get around it?


I'm doing a rest GET callout to an external open database. But I'm getting max size limit error. I know this error is due to 12 MB Heap Size limit.  I'm getting the data from "CPSC Recalls Application Program Interface (API)"  I want to know, what should be my approach to handle the error or reduce the size of data returned from the database.

Trying to figure out how best to build interfaces that retrieve external files between 1-10 MB and display them in the UI.  Right now I have a Lightning Aura Component that calls a web service via HttpRequest and retrieves file metadata, so that users can browse externally stored files.  A second HttpRequest allows the user to either preview or download these files, depending on file type.  Both methods are synchronous currently.  This works, but the current version has to cap file sizes for preview/download at around 5.7 MB, based on the  of 6 MB.    We have also been concerned about the , which we could easily hit if there are multiple users requesting files larger than 1 MB at the same time that other long-running synchronous processes are executing in our org.  Needless to say, I was enthused when I heard that asynchronous processing was coming to Aura Components in Summer '19 in the form of support for Continuations ().  But as I began to test this, I realized my callouts were failing at much lower file size thresholds than 6 MB.  Apparently continuations have specific limits listed in the  whereby callouts and responses can't exceed 1 MB.  Bummer.  Is there a special architecture whereby I can retrieve files of up to 10 MB and display them in the UI, which can be deployed to users at scale?  EDIT OCTOBER 2019  No longer concerned about these types of synchronous concurrent transactions due to a Winter '20 change from Salesforce, .  While the file size cap of 6 MB is still a minor frustration, we no longer have to worry about hitting governor limits due to the volume of requests for external files.


I have a citation that is transliterated from Russian Cyrillic.  @book{kondratyev_radiation_1969,     address = {New York},     series = {International geophysics series},     title = {Radiation in the atmosphere},     volume = {12},     publisher = {Academic Press},     author = {Kondratyev, K. Ya.},     year = {1969},     keywords = {Atmosphere, Solar radiation, Transport theory}, }   This means that the authors second initial is 'Ya' yet when using bibtex the a gets cut off.    I even tried this with no success:  @book{kondratyev_radiation_1969,     address = {New York},     series = {International geophysics series},     title = {Radiation in the atmosphere},     volume = {12},     publisher = {Academic Press},     author = {Kondratyev, K. {Ya}.},     year = {1969},     keywords = {Atmosphere, Solar radiation, Transport theory}, }   Does anyone know how to force bibtex to treat the two letters Ya as one?

BibTeX can abbreviate first names, e.g. change Smith, John to J. Smith.  In some languages, certain (not all) first names must be abbreviated  (it's not optional as in the case of Ch. for Charles).  How can I force BibTeX to do this for particular first names?  EDIT:  I encounter this all the time, including for my own name which should be abbreviated Sz rather than S.  I used to work around the problem by hand editing the reference list in the final version of the paper, but I'd prefer using BibTeX for everything if possible.  Requested example:  .tex file:  \documentclass{article} \begin{document} Text \cite{kovacs, smith}.  \bibliographystyle{abbrv} \bibliography{references} \end{document}    .bib file:  @Book{smith,   author  = "Peter Smith",   title   = "Title 1",   year    = 1980,   publisher = "Addison-Wesley" }  @Book{kovacs,   author  = "Csaba Kov\'{a}cs",   title   = "Title 2",   year    = 1986,   publisher = "Addison-Wesley" }   The output I get:     Text [1, 2].      References       [1] C. Kovács. Title 2. Addison-Wesley, 1986.      [2] P. Smith. Title 1. Addison-Wesley, 1980.   I need to tell bibtex that for Csaba Kovács I need to get Cs. Kovács in the output, and not C. Kovács, as this is incorrect.  The document is in English, so this is not a babel-issue.  This applies only to certain author names, and it's because in Hungarian C and Cs are considered to be distinct units of the alphabet.


I would like to ask this question again since it's passed a long time since the original post and many things have changed since then.   In my case I am using amazon cloud drive app on my macbook pro and when it's running pretty much I can't do anything else with the internet. Preferably I would like to be able to control the upload speed and download speed separately.

I notice that iTunes seems to suck up all my bandwidth and doesn’t play nice with other applications that use the web when it's downloading.  In fact, it doesn't even give itself enough bandwidth when browsing the iTunes Store while downloading large or many files (podcasts, TV shows, large apps, etc).  I'm not concerned with getting all my downloads as soon as possible, they're really low priority, and I'd rather not have to do this while I'm awake, but I can't hit the refresh button if I'm in bed and forgot it already.  Is there an application or tool via the Terminal to limit the download bandwidth that iTunes gets without also hindering web browsers or other applications?  FOSS/GPL software is preferable, but pay software might be acceptable too.


As a part of me learning Japanese I want to eventually make my computer completely in Japanese, however there is one problem, in all the Japanese calendars I have the week starts on Sunday as opposed to Monday, however even when changing the language of the calendar (the built-in one accessible through the top-bar), the week still is displayed as starting on Monday. I am sure that I have seen an option to change this before, I just can't seem to find it now, but maybe I saw that option on another DE.  I am running Ubuntu GNOME 16.04 with GNOME 3.20, how can I set it so that the built-in calendar shows the week starting from Sunday?

What is the recommended way to change the first day of the week to Monday (instead of Sunday, as in the screenshot below)?     I couldn't find anything related in Clock Preferences, nor in System -> Preferences, or System -> Administration.  This probably has something to do with tweaking locales, so here's (possibly relevant) output from locale:  LANG=en_US.utf8 LC_CTYPE="en_US.utf8" LC_NUMERIC="en_US.utf8" LC_TIME="en_US.utf8" ... LC_ALL=   NB: I want to keep English as the UI language both in GNOME and on command line. Dates are currently displayed like this (e.g. ls -l): 2010-10-06 15:32, and I also want to keep that as it is.


I have a Minolta MC Macro Rokkor-X  QF  1 : 3.5 f = 50 mm lens along with a set of extension tubes (12 mm – 20 mm – 36 mm) and auto bellows 1 – all Minolta. Is there a digital camera body that these would work on? I would like to use these for various types of macro photos.  The body they came with is a film SRT 101 – I am not interested in film – I would like to go digital. Any suggestions would help.

I am looking at some older lenses for sale.  There are a lot of Minolta MC and MD mount lenses out there.  Can they be used on an AF mount body at all (as a fully manual lens)?  Will either of the MC or MD lenses have any automatic features (aperture, focus, etc)?  I am looking to update a 1990's era Minolta film camera, so it is not clear whether these older lenses will work or not.  I see from this question, , that it appears that older lenses do not work with the AF mounts?  Will they not fit at all?


I've installed hplip-3.19.3.run on my Ubuntu 16.04 to use my LaserJet M1132 MFP and the driver was installed, but it keeps asking for an installation of proprietary plugin. I downloaded the plugin from the HP site and passing it through a existing location but the installation always fails:      I tried to run the plugin file through the terminal:   root@pc:/home/user/Downloads# sh hplip-3.19.3-plugin.run Verifying archive integrity... All good. Uncompressing HPLIP 3.19.3 Plugin  Self Extracting Archive..............................................................  HP Linux Imaging and Printing System (ver. 3.19.3) Plugin Installer ver. 3.0  Copyright (c) 2001-18 HP Development Company, LP This software comes with ABSOLUTELY NO WARRANTY. This is free software, and you are welcome to distribute it under certain conditions. See COPYING file for more details.  Plug-in version: 3.19.3 Installed HPLIP version: 3.19.3 Number of files to install: 64   Done.   But I'm still getting the installation required plugin message.     Still no printing... It seems that the printer getd the print command  but the paper is blank.  Can anyone can help me?

Let's assume that one has some modern HP printer and/or scanner which is  supported by HPLIP package from official repository. Or supported by newer version of HPLIP package (see  about installation).  From official documentation () it is known that device needs proprietary/binary driver or plugin.  How should one install such plugin?


In python I can't match all character including newline. This is the string     <ebl:NotificationSignature xmlns:ebl="urn:ebay:apis:eBLBaseComponents">   4tzL1OLLe3eEchFIDFFJbA==</ebl:NotificationSignature>   This is the regex I've used  re.findall('<ebl:NotificationSignature xmlns:ebl="urn:ebay:apis:eBLBaseComponents>"(.*?)</ebl:NotificationSignature>', body)   I tried with this one:      re.findall('<ebl:NotificationSignature xmlns:ebl="urn:ebay:apis:eBLBaseComponents>"(.*?|\n*)</ebl:NotificationSignature>', body)   They return nothing. I am using python 2.7.

For example, this regex  (.*)<FooBar>   will match:  abcde<FooBar>   But how do I get it to match across multiple lines?  abcde fghij<FooBar>


I have the following problem. Here's the code I use  \documentclass[11pt,reqno,oneside]{report}  % openright \usepackage{t1enc} \usepackage[latin1]{inputenc} \usepackage[italian]{babel} \usepackage{graphicx} \usepackage{epstopdf} \usepackage{setspace} \usepackage{hyperref} \usepackage{amsmath,stmaryrd} \usepackage{verbatim} \usepackage{amsmath} \usepackage{amsfonts} \usepackage{float} \usepackage{caption} \usepackage{amsmath,amsthm, amsfonts, amssymb, amscd, enumerate,mathrsfs, color} \usepackage[all]{xy} \usepackage{amsmath} \usepackage{filecontents} \usepackage{hyperref} \begin{document} bla bla bla (see \ref{fig1}) \begin{figure}[H] \includegraphics[scale=0.5]{example-image} \caption{Description.}\label{fig1} \end{figure} \end{document}   Before the beginning of the figure, I write "bla bla bla (see \ref{fig1})" but, once compiled, in \ref{fig1} appears "??" instead of the number of the figure (which is 0.0.1)..  Can someone help me to solve this issue?  Thank You

I have some charts embedded in figures, and I want to be able to refer to them easily using the "Figure x" notation. I'm doing it like this (in this order):  \documentclass[12pt,letterpaper]{article}  ...  \section*{Results} ...we performed a linear regression to obtain a standard curve  (Figure~\ref{0:stdcurve})....  \pagebreak \section*{Results (Graphs)} \subsection*{Construction of Standard Graph for PNP} \begin{figure}[h]   % Figure 1     \centering     \includegraphics[scale=1]{kinematics-res/graph0-1}     \caption{The standard curve for PNP.}     \label{0:stdcurve} \end{figure}   However, instead of getting the output "...to obtain a standard curve (Figure 1)...", I just get "...to obtain a standard curve (Figure ??)..."  I also noticed that the PDFLaTeX compiler is generating warnings saying that it couldn't find the reference of the name 0:stdcurve. Why am I getting these warnings?


How can we use npm modules in LWC? I'm trying to use  library in my LWC component. This library is also available in CDN, can we use it in a static resource?

I'm trying to use an external javascript library in my lightning web component, this include two external CDNs one css and one js.  How can I load them in my component?


Almost everything about Rey is purposefully left a mystery. The film strongly hints that she’s related to one of our main characters—but since we get very little indication from Leia, most people think she’s related to Luke. That’s bolstered by the fact when Kylo Ren reads her mind, he sees an island with water. This is a huge clue. Is he seeing Rey’s future, from the end of the film, or her past, when she was with Luke before?

In an  about The Force Awakens, the author suggests that:      Rey is Luke’s daughter.   I’ve missed any indicators of any such relationship while watching the movie.       For instance, I took neither Luke’s lightsaber calling out to Rey, nor her hug of consolation with General Organa as such. Is there any evidence that Luke is Rey’s father?    Is it known who Rey’s parents are?


>>> sample = "asdf" >>> sample[-1:0]   I thought it would start with the last character up to the first position (but not including). However, it returns '' when I expected f. Why is this happening?

I need a good explanation (references are a plus) on Python's slice notation.   To me, this notation needs a bit of picking up.   It looks extremely powerful, but I haven't quite got my head around it.


I'm not a professional photographer and I have an NX3000. I found an analogic N50 that is no longer working, but is there any way i can still use the lens, an AF Nikkor 35-80 Mm F4, on my NX?   Thanks :)

I've got some lenses of brand X, but I've just got a new camera of brand Y. How can I tell if it's possible to use my lenses on my camera? I accept that I may lose a lot of automatic functionality like autofocus, aperture control and metering when using an adapter to connect the two.


I was wondering if anyone knows any link to an iso of 18.04 Desktop (not server) without a desktop environment. Sure i could install ubuntu and uninstall the desktop environment, but that would be too much work.

I would like to install Ubuntu without the GUI so that it's all command/text based?


I know we will have to use double integration. But I need some help in making and solving the equation. The example of these scenarios is the time taken for an object falling towards Earth from Infinity. PS: I have formal mathematical knowledge till Calculus BC only. So, if you use higher level mathematical tools, please name them so I can look them up.

My friend and I have been wracking our heads with this one for the past 3 hours... We have 2 point masses, $m$ and $M$ in a perfect world separated by radius r.  Starting from rest, they both begin to accelerate towards each other. So we have the gravitational force between them as:  $$F_g ~=~ G\frac{Mm}{r^2}$$  How do we find out at what time they will collide?  What we're having trouble with is this function being a function of $r$, but I have suspected it as actually a function of $t$ due to the units of $G$ being $N(m/kg)^2$.  I've tried taking a number of integrals, which haven't really yielded anything useful.  Any guidance?  No, this is not an actual homework problem, we're just 2 math/physics/computer people who are very bored at work :)


I have a data directory has has three sub-directories and each sub-directory has three different sub-directories. And I need to read two different files from the last sub-directory. How can I accomplish this? I tried this using the below code and I am not able to navigate through all the sub-directories. cd $datadir  for dirs in *;      do      cd $dirs               for folders in *;               do               echo $folders;                file1=$(find "$folders" -name '*regADNI.nii.gz');             file2=$(find "$folders" -name '*0.25mm-Crop.nii.gz');              echo $file1             echo $file2               fname=$(echo "$file1" | sed 's|\(.*\)/.*|\1|');             #echo $fname              echo "***************"                      done      cd .     pwd   Following is the folder organization  Can anyone help me with this? Thanks Anandh.

How do I work recursively through a directory tree and execute a specific command on each file, and output the path, filename, extension, filesize and some other specific text to a single file in bash.


Officially, proficiency in the German language is not required for assistant professor positions. However, it is clear that the assistant professor is supposed to teach bachelor students (most probably in German). What are the unpublished requirements regarding language skills? For someone with basic to intermediate level, is it worth applying for this position?

I am a Computer Science PhD student aiming for an Academic career. One of the options I am considering after I receive the degree is to apply for a W1 professor position in Germany (Junior professor).   My question is very specific to Germany. Is there a chance I can become a Junior professor without being fluent in German? Most of the job postings I come across are actually written in German. Some of them do not mention German knowledge as a requirement, but it could be that it goes without saying.   I know that many courses, particularly in master programs, are taught in English. So I am sure there is a capacity to teach in English. But I am wondering if there is a culture of preferring and only accepting German speakers. Because if that's the case, I should start putting back up options.   Obviously I could work on my German. But my question is assuming I did not reach the required level of German until the time I start applying for Junior professorship.


Why am I so bothered when a topic is being explained, the speaker interrupts the flow and inserts "but more importantly..."  This usage is very, very common. But is it consistent with English grammar? My inclination would be to say "but more important..." and then proceed to explain what I wish to insert. Am I incorrect?

I was always under impression that "most important" is correct usage when going through the list of things.     We need to pack socks, toothbrushes for the trip, but most important is to pack underwear.   However watching  Apple presentations I've noticed they always say "most importantly".  Could you please explain how to use this correctly?     But most importantly, Gallo said, it's evident that Cook cares deeply about Apple.


What functions satisfy $f \circ g = g \circ f\ne \text{id}$ and $f \ne g$?   Some thoughts: This is fulfilled for $f(x) := \alpha x$ and $g(x) := \beta x$ for $\alpha, \beta \in \mathbb{R}$ such that $\alpha \beta \ne 1$ and $x \in \mathbb{R}$ because of commutativity of real numbers, but are there other not so trivial examples and how can they be characterised?  Edit to reflect how this shouldn't be a duplicate. The accepted answer on the suggested duplicate is very interesting and informative but only deals with polynomials / rational functions and there are a lot of other functions that could fit this description (and if not, why?).

Today I was thinking about composition of functions.  It has nice properties, its always associative, there is an identity, and if we restrict to bijective functions then we have an inverse.  But then I thought about commutativity.  My first intuition was that bijective self maps of a space should commute but then I saw some counter-examples. The symmetric group is only abelian if $n \le 2$ so clearly there need to be more restrictions on functions than bijectivity for them to commute.  The only examples I could think of were boring things like multiplying by a constant or maximal tori of groups like $O(n)$ (maybe less boring).  My question: In a euclidean space, what are (edit) some nice characterizations of sets of functions that commute? What about in a more general space?   Bonus: Is this notion of commutativity important anywhere in analysis?


I am looking to buy a book that my father read as a boy, for his next birthday.  I know very little about it except the protagonist is able to bodily trans-locate in a manner referred to specifically as a 'Jaunt' or 'jaunting'.  My father's childhood was in the late 1930's through the 40's, so I would guess this is relatively early SciFi.

There's a story my grandpa use to tell me when I was younger, about the sole survivor of of an attack on a mining vessel in space. The man lives in space for months/years, ignored by the company he worked for and never rescued. Then when he thinks he is being rescued, it's actually another set of raiders who attack him and kidnap him.  He then wakes up in captivity in some sort of prison inside of an asteroid, and has a word tattooed on his forehead. My grandpa called him Ronin (that's what the tattoo on his forehead said) but I don't know what the character's real name is. Anyways, he learns that he has the ability to teleport after having a brush with death and decides to make his way back to Earth so that he can exact revenge on the mining company who abandoned him and left him floating to die.  Does anyone know what this story or book may be? My grandpa told it to me when I was little, he said that he got it from a book he use to love reading when he was younger. I'm assuming the book is very old (possibly pre 1940's as he was born in the 20s). I can't ask him as he is no longer alive. I'm also unsure as to whether or not all the details in the story he told me, are the same as in the original.


Let $p(x)$ be polynomial with integer coefficients, such that $p(0)$ and $p(1)$ are both odd. What is the maximum possible number of integer roots this polynomial can have?

This came up an a training piece for the Putnam Competition and also in Ireland and Rosen.  The question posed was basically:  Let $p(x)$ be a polynomial with integer coefficients satisfying that $p(0)$ and $p(1)$ are odd. Show that $p$ has no integer zeros.  I&R give an example:  $p(x) = x^2 - 117x + 31$  and show (no problem) that for any $n$ whether even or odd, $p(n)$ will be odd. And claim that this shows $p(n)$ will never be $0$.  I can see, e.g., that $x^2 + 2x + 1$ will be odd substituting an even $n$ and even for an odd $n$.   But would appreciate help in understanding the underlying math and what is happening here.  Also, as a second part, can a general statement about the existence of an integer solution be made if $n$, even and odd, generates an even and an odd as in the last example.  I can see that if you look at these equations (mod $2$), you can distinguish whether there is an integer solution. And I would guess this is intimately connected with the question.  Thanks as always.


I planned to upgrade from Ubuntu 18.04 to Ubuntu 19.10. I run Ubuntu on a separate partition from Windows, so my laptop has a dual boot with Windows 10 and Ubuntu. Upgrading it turned my Ubuntu 18.04 into a CLI version instead of the GUI/Desktop.   I still have the files there, however, I want to go back to desktop environment mode. I already upgraded to 19.10 while taking advantage of the CLI mode in Ubuntu, but it was still tono avail. I still cannot install ubuntu-desktop because of unmet dependencies.   When I tried to install the unmet dependencies, it kept getting worse. It looks like the packages that were installed were broken when I upgraded it using CLI.

After upgrading from 10.04 to 12.04 I am trying to install different packages.  For instance ia32-libs and skype (4.0).  When trying to install these, I am getting the 'Unable to correct problems, you have held broken packages' error message.   Output of commands:  sudo apt-get install -f Reading package lists... Done Building dependency tree        Reading state information... Done 0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.   After running this:  sudo dpkg --configure -a foo@foo:~$ sudo apt-get install -f Reading package lists... Done Building dependency tree        Reading state information... Done 0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.


The 's 20th-level Emissary of Redemption feature (XGtE, p. 39) gives you resistance to all damage dealt by other creatures and automatically does radiant damage to creatures that attack you. However, it states:     If you attack a creature, cast a spell on it, or deal damage to it by any means but this feature, neither benefit works against that creature until you finish a long rest.   Does attempting to grapple, shove, or disarm a creature without actually damaging it count as attacking it, and therefore cancel the effect of Emissary of Redemption where that creature is concerned?

The  feat enables you to not get opportunity attacks from creatures you try to attack.  Does it still apply if the attack you made was a Grapple or Shove ?


I made the mistake of upgrading OTA to Lollipop (5.0.2) since then have been considering flushing the device down the toilet:   Unable to answer incoming calls half the time. Unintuitive UI update. Regular drop outs when using as data hotspot.   Has anyone managed to get there phone back to KitKat and if so how did you do it?  My phone is the Australian Dual Sim unlocked retail version.  Apologies to anyone that thinks it is lazy for me not to wade through every generic answer and roll the dice on bricking the phone without at least asking if someone has succeeded (or failed) with identical circumstances.

I am having a problem while gaming on my new android update on moto g (2nd gen). So, i want to downgrade the android version please help me out.


On the same computer, I have two user accounts, one for work and the other personal. On Ubuntu 18.04 I can access, for some reason, files from one account if I am logged in in to the other (from the command line, or programs just open them). How can I prevent this? How did this happen?

I just added a new, underprivileged "desktop user," and I was surprised to discover that it can see the files in my home folder.  What is the rational for setting up such lax permissions?


I try to prove that $[0,1]$ is connected.I have to  follow  the next steps: $R$ is complete using the construction of $R$ with Cauchy sequences $\Rightarrow$ $[0,1]$ is connected.How can I prove that?

I don't understand the following proof of that every interval is connected in $\mathbb{R}$.     Let $Y$ be an interval in $\mathbb{R}$ and suppose that $Y$ is not connected.      Then $Y=A\cup B$, where $A,B\subseteq Y$ are open in $Y$, $A,B\neq\emptyset$ and $A\cap B=\emptyset$. Let $a\in A$ and $b\in B$. Without loss of generality, $a<b$.       Let $\alpha=\sup\{x\in\mathbb{R}:[a,x)\cap Y\subseteq A\}$.      Then $\alpha\le b$ and $\alpha\in Y$. It is clear that $\alpha\in Cl_{Y}(A)$, and $A$ is closed in $Y$, then $\alpha\in A$. Since $A$ is open in $Y$, $Y$ is an interval, $b\in Y\setminus A$ and $\alpha <b$, then there exists $r>0$ such that $(\alpha-r,\alpha+r)\cap Y\subseteq A$. We can conclude that $[a,\alpha+r)\cap Y\subseteq A$, which is a contradiction.   I don't understand why $\alpha\le b$ and $\alpha\in Y$. Can anyone explain this to me?  Thanks.


I wanted to know if I buy something off the pre-installed Ubuntu Amazon App does canonical or the Ubuntu project get commission from it? 16.04 version of the app has significantly improved since the 14.04 version but it's still has a few odds and ends that make me use the web browser instead, when I am ready to make a purchase I go to the Ubuntu Amazon app to finalize it because I am hoping they get some commission from the sale. Do they or am I just wasting my time?

Ubuntu 12.10 has a new feature to search and buy from Amazon, either from the Dash, or from a unity WebApp. This is quite controversial, but for my part, I quite ok with it. So when I buy something from Amazon (which I did before, and I'll do tomorow), I'd like to make sure the affiliate revenue are really given to Ubuntu/Canonical: I would have bought anyway, so financing my prefered OS by doing so makes sense to me.  How does it work, and how can I know my order get accounted to Ubuntu/Canonical affiliate program ? What if I navigate the amazon site before I buy ? What if I login or logout from Amazon, does Ubuntu still benefit from my order ?


I'm using bmatrix environment from the amsmath package, and I'm trying to do something like this:  \documentclass{article} \usepackage{amsmath}   \begin{document}      \begin{equation}          \begin{bmatrix}              1 & 2 & 3 & 4 & 5 & 6 & 7 & 8 & 9 & 10 & 11\\          \end{bmatrix}     \end{equation}  \end{document}   However, pdfLaTeX returns an error: "Extra alignment tab has been changed to \cr", and in the output the extra element is moved to the next row. (If I remove one element, then it works perfectly fine). I guess this means that I've hit some hard limit on the number of tab stops in a matrix. Is there a way to change this?  The elements in the matrix are short and could fit perfectly on a single row.


How should units be written in a phrase like 50-100 (fifty to a hundred).  Would it be 50-100cm or 50cm-100cm?

When specifying a range of values that have a unit of measure associated with them, what is the best practice for where to include the unit of measure?      1lb - 20lb   Or     1 - 20lb   And how would this apply when using metric prefixes?     1KΩ - 20MΩ   Or     1K - 20MΩ


Writing a long document, compilation with Texmaker becomes too slow, so when I want to see how it looks, I loose time (not too much, but it is getting worse because of document's size).  Is there any way to compile faster?

Usually I don't mind about LaTeX's compilation speed, because a paper of less than 20 pages is compiled rather fast.  However, I am working on a large document - A report with more than 80 pages.  Compilation times are starting to slow me down.  I saw the couple of answers here on this topic, but most of my graphics are external and I don't use Tikz.  As a matter of fact, I'm not sure what's slowing the compilation down, other than the amount of text and required layout.   What's your best speeding-tex-up trick, other than externalizing graphics and pre-compiling the preamble? How can I know what's slowing TeX down?


So learning how to navigate and edit in VI but the tutorial I'm following on Udemy (using Ubuntu) shows a slightly different Vi where if they are in command mode or insert mode, the terminal window will show which mode they're in.  Where can I configure this?  Basically what I would like to know is how can I display terminal to tell me which mode I'm in.  EDIT: using vi, version 8.0.1453 on Kubuntu at the moment  EDIT2: I installed VIM and that'll do what I need, thanks anyway mates

When I open up the Vim editor, it's supposed to show at the bottom of the screen whether I'm in Input mode or not. But it stays blank whether I'm in Command mode or in Input mode.  Also, vimtutor doesn't work. All I get is a blank screen without any instructions.  It's the same whether I open up a terminal or use a virtual console.  Any ideas what might be wrong?


I am aware that it may be a duplicate question, but I spent over an hour trying to find a proper proof and I failed. One may define inner product of polynomials $p, q$ as integral: $$\langle p, q \rangle = \int_a^b p(x)q(x) dx.$$ Inner product should satisfy following constraints:    for each polynomials $p, q$: $\langle p, q \rangle = \langle q, p \rangle$ - this is quite obvious linearity - also easy to prove for each polynomial $p \neq 0$: $\langle p, p \rangle > 0$ - that's what troubles me   If I take any polynomial $p$, how can I be sure that the integral of $p^2$ is not $0$? I don't really see any argument that such a non-zero polynomial doesn't exist.

Prove that $\int_a^b f(x)\,dx  \gt 0$ if $f \geq 0$ for all $x \in [a,b]$ and $f$ is continuous at $x_0 \in [a,b]$ and $f(x_0) \gt 0$  EDIT. Please ignore below. It is very confusing actually -.-    Note: After typing this all out, I think I realized that my proof is complete, but I'll just post it to make sure :)  Attempt:   Find a partition $P = \{t_0,\ldots,t_n\}$ of $[a,b]$ s.t. $f(x)\gt f(x_0)/2$ for any $x \in [t_{i-1},t_i]$  Thus, the lower sum, $L(f,P)\geq x_0 (t_{i}-t_{i-1})/2 > 0$  [Basic Idea: since f is continuous at $x_0$, in the worst case scenario (i.e. $f=0$ at all points except in a nbhd of $x_0$) there must be some "bump" at $x_0$, which prevents the integral from actually equaling $0$. If we can find just one lower sum of a partition to be $> 0$, we will be done (I think...)]


Mordenkainen's Private Sanctum says that  planar travel is blocked within the warded area  and the portable hole's description states that  the cylindrical space within the hole exists on a different plane.  Does this mean that portable holes' contents can't be accessed within a private sanctum?

Private Sanctum states:  • Planar Travel is blocked within the warded area.  Rope Trick states:  ... an Invisible entrance opens to an extradimensional space that lasts until the spell ends. The extradimensional space can be reached by climbing to the top of the rope.  Would Private Sanctum prevent Rope Trick from being used? RAW it does not seem like it.


I have log files like this:  tmp_1_2_3_4_5.LOG ...   I need to change name like this:  1_2_3_4_5.LOG   I try:  rename 's/^tmp+_//' *   It's working on Debian, but not working on Red Hat.  How can I do this with mv command?

I need to rename files names like this  transform.php?dappName=Test&transformer=YAML&v_id=XXXXX   to just this  XXXXX.txt   How can I do it?  I understand that i need more than one mv command because they are at least 25000 files.


I recently came across this interesting fact:   Take some (pseudo)random numbers between $0$ and $1$.  Now sum these numbers and count how many are needed in order for the sum to be greater than $1$.  If you repeat the experiment $n$ times, you will see that, on average, you need $\mathrm{e}$ (Euler's number) numbers!   My mind is blown! But why? How does this work?

I define $X_i$ as a random variable that is uniformly distributed between (0,1). What is the expected number of such variables I require to make the sum go just higher than 1.  Thanks


What I want to achieve is very similar to , but the solution offered seems not to work in precisely the cases I need it to work! I'm placing enumerate and itemize environments inside a theorem, definition, proposition, or example environment, and I want the first item to be in a new line after the label.  Here's a working example with multiple situations I have so far.  \documentclass{article} \usepackage{amsthm}  \theoremstyle{plain} \newtheorem{theo}{Theorem}%          Regular theorem env.  \newtheoremstyle{break}% name   {\topsep}%   Space above, empty = `usual value'   {\topsep}%   Space below   {\itshape}%  Body font   {}%          Indent amount (empty = no indent, \parindent = para indent)   {\bfseries}% Thm head font   {.}%         Punctuation after thm head   {\newline}%  Space after thm head: \newline = linebreak   {}%          Thm head spec \theoremstyle{break} \newtheorem{enumtheo}{NTheorem}%    Theorem env. for lists  \begin{document}  \begin{theo}[No list with theo environment] A little bit of text. \end{theo}  \begin{enumtheo}[No list with enumtheo environment] A little bit of text. \end{enumtheo}  \begin{theo}[List with theo environment] \begin{enumerate} \item A little bit of text. \item A little bit of text. \end{enumerate} \end{theo}  \begin{enumtheo}[List with enumtheo environment] \begin{enumerate} \item A little bit of text. \item A little bit of text. \end{enumerate} \end{enumtheo}  \begin{enumtheo}[List with enumtheo environment and a newline]$ $\newline \begin{enumerate} \item A little bit of text. \item A little bit of text. \end{enumerate} \end{enumtheo}  \end{document}   The output is the following:   I want something like NTheorem 3 but without the horrible gap. NTheorem 2 should have worked as intended, but apparently the enumerate environment messes it up and disables the linebreak.  I don't mind having to create an alternate environment for theorems, definitions, examples, and propositions, but I also want to have different labels for items (e.g. numbers, letters, itemize,...), so ideally there would be a solution that wouldn't involve creating over 4*3 different custom environments.

I'm currently writing up some solutions, and I like to rewrite the problem before answering it.   I've set exercise to be a theorem environment, and the code I'm using is  \begin{exercise}  \begin{enumerate}  \item Show that $R$ is symmetric iff $R^{-1}\subseteq R$. \item Show that $R$ is transitive iff $R\circ R\subseteq R$. \end{enumerate} \begin{proof} \end{proof} \end{exercise}   However, when I build, the first item (a) appears immediately to the right of the Exercise heading, and the second item (b) appears below and indented:    I've tried using \newline and \linebreak, and even skipping a line before typing \begin{enumerate} after the \begin{exercise} command but those don't work. Is there a way to push (a) down below Exercise 3.32. so that it's lined up with (b)? Thank you.  As requested, my preamble is:  \documentclass[11pt]{article} \input{other/packages.tex} \input{other/theoremdef.tex}   where packages.tex is  \usepackage{amsthm} \usepackage{amsmath} \usepackage{amscd} \usepackage{url} \usepackage[top=1.3in, bottom=1.3in, left=1.3in, right=1.3in]{geometry}  % header and footer \pagestyle{headings}  \usepackage{amssymb} \usepackage{amsfonts} \usepackage{stackrel} \usepackage{mathrsfs} \usepackage{verbatim} \usepackage{enumerate} \usepackage{hyperref} \usepackage{xy} \input xy \xyoption{all}   And theoremdef.tex is:  \newtheorem{exercise}{\bf Exercise} \newcommand{\dom}{\text{dom}\ } \newcommand{\ran}{\text{ran}\ } \newcommand{\fld}{\text{fld}\ } \newcommand{\op}[2]{\langle #1,#2\rangle} \newcommand{\ot}[3]{\langle #1,#2,#3\rangle} \newcommand{\ms}[1]{\mathscr{#1}}


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

Whenever I do camera tracking in Blender the reconstruction is always zooming out or not on the axis. I have a great quality camera, but the end results of the camera tracking always has the model sliding. If you have a solution please tell me.


I just bought my first DSLR camera Nikon D5300 and currently I only have the kit lenses. I am looking to get some new ones soon to use them to take pictures of the moon and maybe even the stars. As the options out there are countless, can anyone suggest to me the best price for value sense for this purpose? I am looking for something around £100 or less.   Thanks

In optimal world I would buy a lens that is good in every way. But I'm on a budget and have to find a balance in quality and price. I'm looking for a lens for star photography, so in my case it will be a wide angle lens with good characteristics for capturing points of light in a dark sky. What would those characteristics be?  So far I've learned about , which seems like a thing to note when comparing different lenses for star photography. It would be quite disappointing if stars turned into long teardrops on the edges of a photograph even when every precaution was taken to make all stars sharp round points of light.  Vignetting would be an example of lens characteristic not so important in this use.  Many characteristics of a lens turn better when aperture is slightly stopped down, but I suppose I'd be wanting to use a lens with wide open aperture when trying to capture the stars in a dark night sky.  I'm not asking for lens recommendations. But, as an example of what kind of lenses I've been looking at, I name  manual focus lens. Its price level is $350'ish in Amazon and seems to run with name Rokinon too. It seems to be reasonably sharp even when wide open - my camera is an APS-C sensor camera.


I upgraded from 11.10 to 12.04 and now my launcher is missing. I opened terminal using CTRL+ALT+T and the menu shows but the GUI (bar) window decorations above that is missing.  Things like CTRL+TAB and image previewer don't work. I've tried whats mentioned  but no luck.  Another Screenshot of my GUI looks :

When I login, nothing happens.   I am presented with my desktop wallpaper.    No Dash, no Launcher, nothing.


Disclaimer: I don't have a whole ton of experience with Java Generics, but my colleagues and I just spent a solid hour trying to decipher an interface that was structured like this:  interface HasAttributes<A extends HasAttributes<A, B>,                          B extends HasAttributesType<B>> extends Identification<B> {   What exactly does it mean when an interface generic takes a type parameter that is itself?  What does this do?

I thought I understood Java generics pretty well, but then I came across the following in java.lang.Enum:  class Enum<E extends Enum<E>>   Could someone explain how to interpret this type parameter? Bonus points for providing other examples of where a similar type parameter could be used.


I have  bla $ H $ bla bla $ 2 \times 2 $ . blabla: \begin{equation} H = \theta \textbf{I} + \textbf{ \tau } \cdot \textbf{a}, \end{equation}   Why does it give me the following error:  ! Missing $ inserted. <inserted text> $ l.206 H = \theta \textbf{I} + \textbf{ \tau } \cdot \textbf{a},   Can anyone help?

To make Latin-letter variables bold I can use e.g. \mathbf{a}, but while putting Greek letters or symbols such as \nabla inside \mathbf doesn't cause any errors or warnings, it also doesn't do anything else.  What is the best way to make bold math symbols, in particular Greek letters and \nabla?


Since a post is only considered spam if the user is associated with the product promoted, mods need evidence of the association, and .  As such, the flagging user needs to provide that evidence with the flag -- otherwise, they're forced to use a custom flag as suggested in the linked question, which defeats the purpose of a dedicated spam flag.    The justification for rejecting the previous such request, , turned out  so it may no longer apply. (That post has been updated since, with new reasoning. I updated this post with the new figures, and also gave an update at the bottom.)  It's questionable in the first place: there's no statistics on how many flags were mishandled (, rather high to really say anything) or how much time the mods wasted looking for evidence -- so there's no way to estimate the magnitude of the problem with just the data. Maybe the SO mods themselves can provide feedback here.  The previous suggestion to use comments to show evidence sort of works --    if both users and mods know to look there for evidence   which is totally not obvious due to inconsistency: the only comments to a mod flag currently possible come with the flag and are private, unlike post comments   which is reasonable 'cuz a mod flag comment exposes others' wrongdoings and thus can get people into trouble; and   if it doesn't get lost/buried among other comments   quite possible is self-promotion wasn't detected early    So, it does provide a way, but that way is far from being intuitive, convenient or, if privacy is a concern, even acceptable.    , @JonEricson now argues that obvious and non-obvious spam are significantly different things and should be handled differently.   If that's the case, the note near the spam flag entry needs to say something along the lines of: "if the fact the post is spam is not obvious, use a custom flag instead and provide incriminating evidence":   so that the users know that they should be using this workflow -- this is completely non-obvious this workflow will give hard numbers to find out if such cases really are frequent enough to warrant a more streamlined mechanism

, where a user had taken the time to look at the link on a post and realized that the post wasn't just off-topic, it was actually half-decently-disguised spam. So he flagged it as spam, and an overworked mod declined it, giving the questioner the benefit of the doubt. And we probably want mods to be giving the questioner the benefit of the doubt.  We also want to get rid of spam ASAP, and make the lives of mods easier. I'd like to suggest a feature the mod in question mused might be useful: An optional textbox where you can add a note saying why you think it's spam, so the mod can see it easily. In this case, the helpful user who went the extra mile could have written "Site linked doesn't relate at all to the question, instead solicits BitCoins" or similar.  One can leave a comment on the question, but:   People sometimes leave...unhelpful...comments on spam questions, and we don't want mods to have to take the time to read through them hoping for something useful It allows the user flagging the spam to do so and say why without calling attention to themselves publicly     Update: We may well want this for all flags, but in particular I had reason to want it for an NAA flag, so I've posted .


I've read that all items in a freezer are at the temperature at which the freezer are set to (obviously items have to be in the freezer long enough). So, if I put normal tap water in a freezer which is set to -26C (which is what mine is set to) and it freezes, and I leave that ice long enough, it will eventually reach -26C.  What really bothers me is, if I put a +/- 20% saltwater solution in my freezer, and it eventually freezes (by which time regular water have long time been frozen, and according to the statement above should be at the same temperature as the saltwater ice), it feels much more colder than the regular tap water which was left to freeze.  If the statement is true that the regular ice and 20% saltwater ice is both at -26C, why are the saltwater ice feeling so much colder then. Are the online sources I've checked out lying?  I have no physics background, so this makes no sense to me that both ice are at the same temperature

(I apologize for this elementary question. I don't know much about physics.)  Let's say that I put a metal pot in the refrigerator for several hours.  At this point, I guess, the pot and the air (in the refrigerator) have the same temperature.  Now, I touch this pot. It feels very cold. But when I "touch" the air (that is inside the fridge) it doesn't "feel" as cold. I don't feel the same "ouch!" that I feel when I touch the pot.  Why is that? Why does the metal seem colder than air although they both have the same temperature?  (I know that gas has less particles in it in one unit of volume compared to solids and liquids, but since "temperature" means "the average kinetic energy", these fewer air particles are supposed to hit my hand in a velocity that's going to compensate for their lower number, aren't they?)  A related question, for clarification:  If I use a thermometer to measure the temperature of the pot & air (let's assume it's a thermometer that has a probe that can touch objects), will it show the same reading for both? If so, what makes the thermometer different than my hand? I mean, my hand is sort of a thermometer, so why would it fail whereas a non-human thermometer would work?


There was a comic that told the story of a society based in Iceland. The one story line featured an oil tanker stranded in a desert that a military force was extracting oil from. The militay force was from a militaristic group that the Iceland based society was resisting. I recall there were 2 brothers, one belonged to the Icelandic society and the other was the head of the fascist society. At the end, it was revealed that their father had escaped to an orbiting space station.  Trying to recall the name of the comic or the story itself. I am thinkng mid 80's when I read this but could be an earlier time when it was written.

There was a comic that told the story of an underground society. A nuclear war was still going on. Radiation was seeping down into their caverns. A scientist was tasked to find a safer location deeper down. However, he found the mutated remnants of an earlier human society that experienced a previous nuclear war. Trying to recall the name of the comic or the story itself.  I am thinking mid 80's when I read this but could be an earlier time when it was written.


I need to develop a web-based map using existing shapefiles.   Using the web-map, we must be able to select a region and produce contours for that selected region.   Can any one suggest the best open source solutions for this?

I want to start working on a web map at work to map some of our statistics by city.    I have an idea, but I'm not exactly sure where to start.   Are there any definitive resources that provide step by step guidance on how to do this?


I am trying to compile tex document using biblatex to handle references with no success. I am aware of the cycle Latex > Biber > Latex. I always use pdflatex, therefore it should be  pdflatex main.tex biber main[.bcf] pdflatex main.tex   In the first step, I get e.g. Citation 'citekey' on page 53 undefined which is normal as I have not generated the proper reference text. But upon running biber main I get error  Undefined subroutine &Biber::Config::biber_error called at /var/folders/zv/ds3zw_xs2dv4c1jp7m1t44f80000gt/T/par-6973776168797574616d61/cache-ec7adafccc6b3891989ad6eb09778d44c1fecb97/inc/lib/Biber/Config.pm line 640. Any idea how to fix this?

I'm trying to use biblatex and when I compile my document I get an error like the following:  Windows  data source C:\Users\<username>\AppData\Local\Temp\par-5061756c\ cache-890efc00b3ca6b775c7d44a325c1349fb2a3a3bd\inc\lib/Biber/LaTeX/recode_data.xml not found in .   Mac  data source /var/folders/v2/rld0ls7d2935gkvqv5hfr1x00000gn/T/par-616c616e/ cache-cdd483146f82a9655ce063f848d5139480fbf872/inc/lib/Biber/LaTeX/recode_data.xml not found in .   Linux  data source /tmp/par-6963617269756d/cache-f37ab610b7d79b2720a8ee3732849c6821705520 /inc/lib/Biber/LaTeX/recode_data.xml not found in .


You're watching TV or something, and you hear a word1 that you've never heard before. You look up the meaning of this word. This new word is suddenly popping up everywhere!   You're now seeing the word on social media People you know are now saying it It suddenly seems like its popping up everywhere but didn't even exist a day ago!    Is there a word for that?    1 "word" - it can be a word or a phrase (etc.)

For example, when you buy a car, you start becoming more aware of cars with a similar make and model. The number of that type of car hasn't increased, but your awareness of it has.  Similarly, when you learn a new word, you start hearing the same word used in different places. You probably just filtered the word out previously, but now you've become aware of it.   How do you describe the phenomenon when you become more aware of something after an initial or significant exposure or experience with that thing? What term or word can you use?


Sebastian (arrive) ... at Susan's house a little before 9:00 PM, but she (be, not) ... there. She (study, at the library) ... for her final examination in French.   Could you explain, please, what and why verb tenses should be used in the above sentences? If it possible tell me please what 'use' from the following site determines verb tense:

I've been noticing in conversations that people often use past or present or future progressive where I would normally use past, present or future simple. I know some rules about interrupted actions that are always described by progressive tenses. But today during listening some podcast, the lecturer said      Initially I was planning to make this podcast...   So my question is why to use progressive tense here? Could we use simple here? I suppose there is some difference in meaning, but have no idea where to start digging.


I have a menu button, and if you click it, a menu drops down. Then, if you click anywhere on the HTML except for the menu or the button, the menu disappears. I achieved this by using jquery stopPropogation to prevent the $("html").click event from being triggered if the menu or button are clicked.  However, I added a link to my menu that uses method: :delete, and since jquery is disabled within the menu, the method: :delete is ignored as well, and the link sends a GET request.  Is it possible to achieve a menu that closes if you click anywhere but inside the menu or the menu button, but also have a method: :delete link?
BUTTON

   <%= link_to "LOG OUT", logout_path, method: :delete %>

I have some HTML menus, which I show completely when a user clicks on the head of these menus. I would like to hide these elements when the user clicks outside the menus' area.  Is something like this possible with jQuery?  $("#menuscontainer").clickOutsideThisElement(function() {     // Hide the menus });


If we pass a reference variable to method and modify the object's state, the modifications are permanent (Please correct me if I am wrong). Consider the code:   class CardBoard {     Short story = 200;     CardBoard go(CardBoard cb) {                        //....(1)     cb = null;     return cb;     }     public static void main(String[] args) {     CardBoard c1 = new CardBoard();     CardBoard c2 = new CardBoard();     CardBoard c3 = c1.go(c2);       //pass c2 into a method ....(2)     c1 = null;     // do Stuff     } }   When in the above code, we say cb=null and return cb, shouldn't c2 (and also c3) now have null reference? (PS: The original question asks for the objects that are eligible for gc after "//do stuff". The answer is given to be 2, but I am having problem in understanding it.)

I always thought Java uses pass-by-reference. However, I've seen a couple of blog posts (for example, ) that claim that it isn't (the blog post says that Java uses pass-by-value). I don't think I understand the distinction they're making. What is the explanation?


Recently I brought up the idea that $\bar{.9} = 1$ with some friends and asked why or why not. One friend suggested that since $\bar{.9}$ is distinct from 1 in $\mathbb{R}$ they must not be equivalent.  Thoughts?

I've ended up in a debate on a proof for .999˜ being equal to 1 (in the real number system.)  I think the arguments have boiled down to whether or not we can preform variable substitution on one side of the equation, while keeping that variable rather than substituting it on the other side of the equation.  What we are looking at:  Given: x = 0.999˜ (Using the ˜ symbol to represent repeating)     .. A     10x - x     = 9.999˜ - x     9x          = 9.999˜ - x     9(.999˜)    = 9.999˜ - (.999˜)     8.999˜      = 9     ..     OR     .. B     10x - x     = 9.999˜ - x     9x          = 9.999˜ - (0.999˜) // Preform a substitution on ONLY the RHS     9x          = 9     x           = 1     ..  What's so confusing is that both should be right...since 8.999˜ IS equal to 9.  But, since this is a proof you should expect the same representation of the number at the most simplified step (I believe?)  So for simplicity sake my questions are...:   Is the algebra valid in both examples A and B? Does example A act as proof regardless of giving different representations of the same number at the most simplified step?


I was watching Batman Beyond with my daughter and was wondering why there is a giant penny in the bat cave.  I've seen it before in other Batman shows/comics but I was curious what it's origins are.

In Batman #1 in the New 52, when we visit the Batcave for the first time, we see a dinosaur:     What... is up with that? It is a completely awesome cave decoration - but what else is it? Is it a non sequitur or is it a call back to an earlier storyline? I imagine it's the latter – a life-size T-rex model is an expensive piece of decor, even for Bruce Wayne.  Bonus points: are there any other relics from past storylines visible in this Batcave?  Update: here's a shot of the other panel that gives us a view of the "showroom" (including the huge dice).


I'm trying to create a calculator for one of my first projects in java. I ask the user for two number inputs and a symbol to choose the operation. It asks for the inputs then stops once it reaches the if statements to calculate the answer.  import java.util.Scanner; class Calculator{      public static void main(String args[]){         double a;         double b;         double answer;         String symbol;         Scanner in = new Scanner(System.in);         System.out.print("Enter an operation");         symbol = in.nextLine();         System.out.print("Enter the first number");         a = in.nextInt();         System.out.print("Enter the second number");         b = in.nextInt();          if (symbol == "+"){             answer = a+b;             System.out.print(answer);          }         else if (symbol == "-"){             answer = a-b;             System.out.print(answer);          }         else if (symbol == "/"){             answer = a/b;             System.out.print(answer);          }         else if (symbol == "*"){             answer = a*b;             System.out.print(answer);          }     } }   Here is my output  Enter an operation + Enter the first number 4 Enter the second number 5

I've been using the == operator in my program to compare all my strings so far. However, I ran into a bug, changed one of them into .equals() instead, and it fixed the bug.  Is == bad? When should it and should it not be used? What's the difference?


I want to loop over a sequence of numbers in a BASH script, but the bound values are not constants. I know this syntax:  for year in {2000..2010}; do   echo ${year} done   But the values of 2000 and 2010 are changing in my case, so what I am doing right now is this:  for year in `seq ${yeari} ${yeare}`; do   echo ${year} done   Is there a bash-native way to do the same, without using seq?

How do I iterate over a range of numbers in Bash when the range is given by a variable?  I know I can do this (called "sequence expression" in the Bash ):   for i in {1..5}; do echo $i; done   Which gives:     1    2    3    4    5   Yet, how can I replace either of the range endpoints with a variable? This doesn't work:  END=5 for i in {1..$END}; do echo $i; done   Which prints:     {1..5}


Once upon a time on one fortuitous conference, I stumbled upon one of the most outstanding and revered academician in my field. I had a nice question nicely formulated in my head, but when I finally met this towering intellectual figure I was struck with nigh-religious trepidation and lost my marbles for a brief moment. So my question is: When meeting the Einsteins/mega-stars of your subject how do you secure your composure?

I know that they are "just as human as we are", but I feel somewhat uncomfortable to talk nonchalantly with the top-notch math researchers and professors in my department because of their social position, their extremely superior knowledge and talent, and also because of their age.   Still, I feel that it is like a waste to have such interesting mind-expanding people around and not to interact properly and talk about maths when I meet them in the department (outside the lecture hall).    So my question is: according to your experience, what is the best (where best means: most polite, appropriate, acceptable, but also profitable) way to interact and make the most of the presence of such awesome professors? Can I discuss "lower" [mathematical and non-mathematical] subjects with them even though their actual (research) interests lie in much more abstruse topics?  Any suggestion (even in the form of a comment) is really appreciated.


I have a phrase which I want to write, but I'm not sure of the correct grammar.  I want to say:     He sat (dramatic pause) and I (beat) nervous of what he was about to say...   Would I write this as:     He sat. And I, nervous of what he was about to say...   Or     He sat, and I, nervous of what he was about to say...   Or are both wrong and there's a better way?

Since I first learned English, I have been holding this understanding that "and", as a conj. but unlike "but",  can only connect two clauses, not two sentences ended with periods.  But recently, I have seen so many prints, either in entertainment or in academia, where "And" is popularly used in the beginning of a sentence. It seems like the author is trying to connect the sentence just right before and the sentence following "And" in some intended meaning which I don't quite get.  I was wondering if I have been wrong all the time, or if there is a new trend that I fail to understand and accept? How to understand such usage of "and" in rigorous English grammar? If I am right, why it is used differently from "but" in terms of what I mentioned at the beginning of this post?


Examples of appliances I want to protect are: monitors, computers, and printers. I have looked everywhere and I cannot find a solution where I can simply buy a box in the market. These are often times very small and will not fit the appliances I need to be protected. Assumption is that the container will be used for home use in case there is a great flood. So the water pressure isn't likely to be too strong--not like submarines where they dive down to deep altitudes. I can say that a submarine is a massive watertight container that can allow many people and equipment to live inside it. So, creating a watertight container should be possible with similar concepts. I wonder what materials and techniques I should look into to build one myself.

Our home is prone to occasional flooding during the rainy season. There was only one time in 26 years where our home was devastated by the flood reaching up to half of the 2nd floor. This destroyed so much of our things such as our car, electronics, furniture, documents, and etc. Other than that, there are a few instances of flooding that reaches only a few inches into the home but it was also rare. I am considering buying quite an expensive monitor, CPU, and printer but I am thinking that rainy season just arrived and I am afraid they will just get destroyed. The only way I can be reassured I can buy these if I can find some kind of storage solution that if I place my appliances/electronics in them, there is an almost 100% certainty that water will not be able to enter and damage the objects in case it gets submerged (assume the entire thing is submerged for hours to days). I have looked for flood bags, but all I can see everywhere are either sandbags or sandbag-like fibres that absorb water and create a barrier to prevent water from entering, but these are surely only for mild flooding. If it is on the scale where it will reach the items of value,  it will be a massive flood thus a watertight storage solution is the answer. I have been looking but I cannot seem to find any good solution. I am thinking of something like a garbage bag, but I know garbage bags are not the best choice as they are not watertight despite having several layers of them


$$\sum_{n=1}^\infty \frac {(-1)^n|\sin(n)|}{n}$$  I was helping a friend edit a Sequences and Series test for an upcoming state math competition and was recently given this problem. I'm not quite sure how to prove how this series converges, given that most tests that I know (Alternate, Dirichlet's, etc.) are hard to utilize, simply because this series is most likely going to converge conditionally. The tricky thing is that I can't use powerful tests like the ratio or root test because this series does not absolutely converge, yet intuition tells me that it does not diverge either as its plot on Wolfram shows that it tends to $\approx -0.4$ as $x$ approaches infinity (). Any help would be appreciated.  Edit: This problem remains unsolved. Is there any way to prove it's convergence using ?

Study the convergence of $$\displaystyle \sum_{n\geq 1} \frac{(-1)^n|\sin n|}{n}.$$   I am stuck with this series, we need probably some measure of irrationally of $\pi$, unfortunately I am unfamiliar with this. So here is my attempt :  Let $f(x) = \sum \frac{|\sin{n}|}{n} x^n, |x| < 1$  It's not difficult to compute the Fourier series of $|\sin(x)|$ :  $$ \displaystyle|\sin(x)|=\frac{2}{\pi}-\frac{4}{\pi}\sum_{n=1}^{+\infty}\frac{\cos(2nx)}{4n^2-1} $$  Then Fubini's theorem () works very well (because the previous series converges absolutely at $x$ fixed ) and all calculations made, we find that for all $x\in( -1,1)$:  $$ \displaystyle f(x)=\frac{2}{\pi}\sum_{n=1}^{+\infty}\frac{x^n}{n}-\frac{4}{\pi}\sum_{p=1}^{+\infty}\frac{x^2-2x\cos(p)}{(4p^2-1)(x^2-2x\cos(p)+1)} $$  However, the second sum I have not been able to show the convergence. I feel the series diverge because the following series $$ \displaystyle\sum\frac{1}{p^2\sin^2\left(\frac{p}{2}\right)} $$  diverge because  $0$ is an accumulation point of $\displaystyle (n\sin(n))$ sequence.  Any ideas (for the original series) ?


I'm investigating once more my ANSI escape rendering scripts and I've found weird behavior. The output color is defined by background or foreground by both mixed together. Example: echo -e "\x1b[1;30;47m█████▀\x1b[0m" # or printf "\33[1;30;47m█████▀\33[0m\n"  it's a light gray and darker gray, even that the ANSI codes are bold black and white. If I remove white (47) I get black foreground, so it's kind of blending two colors 30 and 47 together. First of all, am I right, is this some kind of blending of colors? Is this behavior some kind of documented and explained in detail and every possible color how to blend two colors? Does it happen for all colors or only black & white? The reason why this is maybe the case is that I have a perfectly fine script for generating ANSI artwork but it's somehow broken for white or gray colors. The code is created based on Wikipedia articles, other similar resources, and also answers on this Q&A that help a lot. EDIT: This is not duplicate, I'm asking about behavior that colors and background mixing have 3 states, one both (BG and FG) apply or either one applies. I'm asking if this is documented somewhere because it seems that this is how ANSI Artwork is rendered. An example is this one:  That renders fine in XFCe terminal but fails to render properly in my code.

I have a problem with colors in my terminal emulator. I am using LXTerminal as my terminal emulator and LXDE as my desktop environment.  The following command is supposed to print red text on grey background:  printf "\n\033[1;31;40m"hello"\033[00m\n\n"   but that does not work. The grey background is missing (red text is OK). On my older machine (Gnome/Gnome Terminal) everything works fine  I have tried installing several other terminal emulators, but the problem persists. I am not even sure whether this issue is related to terminal emulator, or something else. In Console (CTRL+ALT+F1) the background grey color does not work on either machine)  This problem is limited to grey background only. All other colors work OK, for instance the following prints red text on green background.  printf "\n\033[1;31;42m"hello"\033[00m\n\n"   I would appreciate any help. I don't even know where to start troubleshooting.


On a geometry test I forgot the formula for the surface area of a sphere so I derived it and ended up being right. But it seems like my derivation is wrong. I got the surface area formula by taking the derivative of the volume formula, $\frac{4}{3}\pi r^3$. My reasoning was that taking the derivative is equivalent taking the volume of a sphere with radius $r+h$ minus the volume of a sphere with radius $r$ and then dividing by $h$ as $h$ goes to $0$. I figure that if you took the part of the larger sphere that is not in the smaller sphere and laid it flat it would be a prism with height $h$, so its base area (i.e. surface area of the sphere) would be the volume divided by $h$. So my questions are: First, why must $h$ go to $0$? First I tried it with $h = 1$ thinking, since the height is $1$, the base area (i.e. surface area of sphere) would equal the volume. But when $h=1$ you get the wrong formula. Secondly, is the rest of the reasoning correct? Thanks,  Elliot

When differentiated with respect to $r$, the derivative of $\pi r^2$ is $2 \pi r$, which is the circumference of a circle.  Similarly, when the formula for a sphere's volume $\frac{4}{3} \pi r^3$ is differentiated with respect to $r$, we get $4 \pi r^2$.  Is this just a coincidence, or is there some deep explanation for why we should expect this?


I understand that if you want to cash out your HSA you are expected to pay tax and some penalty on that money. The tax part I understand. But what is this penalty exactly and how much would it be? And if a person is leaving the country permanently why should they have to pay  penalty for withdrawing their own contributions from the HSA? Can it be avoided? Just curious. Thanks.

I have lived in US for 5 years, and I (still) have an HSA account with BoA. Now I am living in Europe, and there's a fat chance I'll ever go back to live in US, so I would like to withdraw the money from my HSA, pay the due taxes, of course, and just be able to use them. How exactly I go about that?  Thanks in advance.


I have submitted a paper for a conference organized by the IRES. (details here: ) they accepted my paper within one day and instructed me to register. How will I know it is scam or not? Thanks in advance!

I recently received an invitation to a conference and I'm trying to determine how reputable it is. Is there a good way to go about this?


Let $$l^2=\left\{(x_n):\sum_{n=1}^{\infty}x_n^2<\infty\right\}$$      equipped with the norm   $$\|(x_n)\|=\left(\sum_{n=1}^{\infty}x_n^2\right)^{1/2}.$$      Prove that $l^2$ is complete with respect to the norm $\|\cdot\|$.   Can somebody please check my working?  Here is my working and some of my doubts:  We need to show that every Cauchy sequence in $l^2$ has a limit in $l^2$.   I first define the metric as (am I correct to define it in this way?): $$d((x_n),(x_m))=\|(x_n)-(x_m)\|=\left(\sum_{k=1}^{\infty}((x_n)_k-(x_m)_k)^2\right)^{1/2}$$  Pick any Cauchy sequence and we write it as $d((x_n),(x_m))\to0$.  So $d((x_n),(x_m))=\sqrt{\sum_{k=1}^{\infty}((x_n)_k-(x_m)_k)^2}$ $=\sqrt{\sum_{k=1}^{\infty}(x_n)_k^2-2\sum_{k=1}^{\infty}(x_n)_k(x_m)_k+\sum_{k=1}^{\infty}(x_m)_k^2}$   Since $\sum_{k=1}^{\infty}(x_n)_k^2$ and $\sum_{k=1}^{\infty}(x_m)_k^2$ are both finite, so the sum is finite.  But here are the parts that got me stuck:  Is $\sum_{k=1}^{\infty}(x_n)_k(x_m)_k$ finite? If it is finite we are done isn't it? We have shown that there is a limit.  And my last doubt is how can we show that the limit lies in $l^2$? Do we have to show that it can be written as $\sum_{j=1}^{\infty}x_j^2$ for some $(x_j)$?  EDITTED: I think it is not a duplicated question, I asked some different points.   I really need some help. Many thanks!

Let $l^2$ be the space of square summable sequences with the inner product $\langle x,y\rangle=\sum_\limits{i=1}^\infty x_iy_i$.   (a) show that $l^2$ is H Hilbert space.    To show that it's a Hilbert space I need to show that the space is complete. For that I need to construct a Cauchy sequence and show it converges with respect to the norm. However, I find it confusing to construct a Cauchy sequence of sequences?


I've a question with my homework, I need to do a project in C++, and I need to use Object-oriented Programming, it's a vocabulary with a Binary Search Tree, and I finished it. But I use a struct... with it I break the OOP rules? If yes, how can I convert the struct in an inherited class?  template <typename T> struct BinaryNode {     T key;     BinaryNode<T>* left;     BinaryNode<T>* right;     BinaryNode<T>* parent; };  template <typename T> class BinarySearchTree { private:     BinaryNode<T>* root;     BinaryNode<T>* newNode(T key); public:     BinarySearchTree();     ~BinarySearchTree();      void insert(T key);     BinaryNode<T>* search(T key);     void distance(T key);     void inorderTreeWalk();      void insert(BinaryNode<T>** node, T key);     BinaryNode<T>* search(BinaryNode<T>* node, T key);     void distance(BinaryNode<T>* node, T key);     void inorderTreeWalk(BinaryNode<T>* node);     BinaryNode<T>* remove(BinaryNode<T>* node);      BinaryNode<T>* minimum(BinaryNode<T>* node);     BinaryNode<T>* maximum(BinaryNode<T>* node);     BinaryNode<T>* successor(BinaryNode<T>* node);     bool contains(T key);      BinaryNode<T>* getRoot(); };

This question was .  Now I'd like to learn the differences between a struct and a class in C++. Please discuss the technical differences as well as reasons for choosing one or the other in OO design.  I'll start with an obvious difference:   If you don't specify public: or private:, members of a struct are public by default; members of a class are private by default.   I'm sure there are other differences to be found in the obscure corners of the C++ specification.


Suppose a creature is vulnerable to radiant damage, and is beginning its turn in the area of effect of . It will be taking radiant damage, and the damage roll is a 13. It succeeds on its saving throw, so the damage is halved, but it is vulnerable to radiant damage, so the damage is doubled. Is the damage first halved, giving 6, and then doubled, giving 12? Or is it doubled first, then halved to give 13? Or do the effects cancel, for a total damage of 13?

If a creature has "damage resistance" to non-magical weapons how does the final damage number break down?  Is the weapon damage halved only?  Is the total damage (weapon, STR/DEX dmg. bonus) halved?  Would a rogue attacking with a non-magical weapon and using Sneak Attack get the Sneak Attack dmg. halved?  Same question applies to "damage vulnerable" when damage is doubled.


counting sort implementation:   The have used the below for loop to iterate through a string -  char arr[] = "geeksforgeeks";  for(i = 0; arr[i]; ++i)    ++count[arr[i]];   From google search I could understand that this condition implicitly evaluates to arr[i]!='\0'. Have I understood it correctly ? If I were to use a similar for loop to iterate through an array of integers, would it evaluate to arr[i]!=0 ?   Or is there any better way to iterate through an array of integers when we do not know its size. I am a beginner and please try to provide suggestions which do not involve advanced data structures in C.

How do I determine the size of my array in C?   That is, the number of elements the array can hold?


Evaluate the following infinite product:   $$\lim_{n\to \infty} \prod_{r=1}^n (1+ \frac{1}{a_r}),\\ a_1=1; \quad a_r=r(1+a_{r-1}).$$   I thought of two ways in which this might be evaluated: (1) By taking log and converting into a Riemann series which I saw isn't possible and (2) by converting into a polynomial equation of nth degree where coefficients become sums as per the theory of equations. Right now, I'm stuck, trying to figure out the way to proceed.