Manipulating text in first column only? Example Input:  foobar@example.com foo@example.com,bar@example.com   Example Output:  foobar@example.org foo@example.com,bar@example.com   So, in "normal" circumstances, it would obviously be easy to do something like:  sed 's/.com/.org/g'   But obviously in this case, I only want the suffix in the first column to be manipulated, I want the second column to be left untouched.  I don't mind what tool you propose to use. But I prefer it to available on a standard linux without needing further install (i.e. something like sed or awk or perl would be more preferable to bobsobscuretoolthatneedsinstalling).
modify specific column with sed or awk I have a CSV file that looks like this:  qw12er,foo,0 bn5mgh rt8yp,foo,10 gh78jk bn852mv,foo,852 78ghjkh tgbr,foo,10 ujmyhn wsx2d,foo,0000 ui52ohn tgbr,foo,7418529 ujmyhn ikl896o,foo,22 wsxdc52   I want to modify the 3rd column and remove all numbers and space from the beginning of the 3rd column.  Then output would be as follows:  qw12er,foo,bn5mgh rt8yp,foo,gh78jk bn852mv,foo,78ghjkh tgbr,foo,ujmyhn wsx2d,foo,ui52ohn tgbr,foo,ujmyhn ikl896o,foo,wsxdc52
In the Android App, if a question is closed, I won't be able to leave comments on either the question or any of its answers. There are simply no "Add Comment" buttons available anywhere if the question is closed.  See the screenshot below. The comment adding interface is simply removed on closed questions and their answers &mdash; no Reply button in the toolbar, and no Add Comment button under the question.        Occurs on Android app v1.0.50 and v1.0.51, on a HTC One running Android 4.4.3. How to deal with SQL column names that look like SQL keywords? One of my columns is called from. I can't change the name because I didn't make it. Am I allowed to do something like SELECT from FROM TableName or is there a special syntax to avoid the SQL Server being confused? Where should the period go when using parentheses? For example:     In sentence one, I use this example (which has a parenthesis at the end.)   Should the period be inside, or outside of the parentheses? What about if the entire sentence is a parenthetical (as below)?     (Where does the terminal punctuation go here?)   Is there a hard and fast rule? After these instructions in the Python interpreter one gets a window with a plot:  from matplotlib.pyplot import * plot([1,2,3]) show() # other code   Unfortunately, I don't know how to continue to interactively explore the figure created by show() while the program does further calculations.  Is it possible at all? Sometimes calculations are long and it would help if they would proceed during examination of intermediate results. filling area between 2 functions, with shading Limit of a sequence defined by recursive relation : $ a_n = \sqrt{a_{n-1}a_{n-2}}$ A script on AIX which checks the number of parameters passed and complains if they are not correct:-  if [ "$#" -ge 1 ]; then   ... else   echo 'Usage: myscript &lt;a&gt; [b] [c]' fi   The script sets some environment variables so it is sourced. By that I mean I type the following on my command line. There is no second script, I am not sourcing a script from within another script.  . ./myscript.sh   If I pass it no parameters, I expect it to print out the usage statement but instead it runs using the parameters passed to the previous command that was sourced (not necessarily even this script!).  To double check this I added this line at the beginning of my script to prove that this was the case.  echo $# $@   If I pass it no parameters, it prints out the number and the list of parameters from a previously sourced script.  How do I get it to say $# is zero when I pass it zero parameters and source it?  The smallest possible recreate is a script thus:-  myscript.sh  echo $# $@   and then run it thus:-  . ./myscript.sh a b c   which prints out  3 a b c   then run it again without any parameters thus:-  . ./myscript.sh   which prints out the same  3 a b c   when you would expect it to print out  0   If you don't source the script and just run it thus:-  ./myscript.sh   then it works as expected and prints out  0   I hope that clarifies the issue at hand.  Since I seem to be getting lots of answers to explain why the above doesn't work and no answers to tell me what I should do instead, I thought I would have one more attempt at trying to explain what I am trying to do.  Requirement  I need to write a script that expects at least one parameter and complains if it is not invoked with a said parameter (see the first block of code in my question above), and this script needs to set some environment variables. Because of this second requirement I have assumed that I need to source the script so that the environment variables are still set when the script completes. How can you write a script that can tell when it has not been passed parameters that is also able to set an environment variable? Two Circles and Tangents from Their Centers Problem Let $\Gamma_1$ and $\Gamma_2$ be two non overlapping circles with centers $O_1$ and $O_2$ respectively. From $O_1$, draw the two tangents to $\Gamma_2$ and let them intersect $\Gamma_1$ at points $A$ and $B$. Similarly, from $O_2$, draw the two tangents to $\Gamma_1$ and let them intersect $\Gamma_2$ at points $C$ and $D$.  Prove that $AB=CD$.  I've done some extensive angle chasing on this but have been unable to make any real progress. Can't decide whether $ABCD$ is supposed to be rectangle (as in my diagrams), a parallelogram or even a trapezium. There is a homothety taking one circle to the other but as far as I can see this doesn't help as we don't have a clearly defined center to this.  Any help/hints would be greatly appreciated. Which characters are valid in CSS class names/selectors? What characters/symbols are allowed within the CSS class selectors? I know that the following characters are invalid, but what characters are valid?  ~ ! @ $ % ^ &amp; * ( ) + = , . / ' ; : " ? &gt; &lt; [ ] \ { } | ` # How do we "restore" notepad after crash? How To Make A Solid Object Drop To The Ground Like It Was Liquid So I have a simple bouncing ball animation, but I just wanted to something "weird" for the ending. Is there a way to change the ball's material on the fly, where after the last bounce it changes materials and physical composition from a rigid body(baked animation now) to a fluid sim?  (within 30-40 frames) I know base 2 and base 10 , MB and MiB, but i'm not understanding the byte counts shown for a directory, by du and by windows explorer The du command shows 43G in use. I'm not sure whether that's base 2 in the sense of 2^30 or if it's base 10, in the sense of 10^9.  But anyhow -   Running this du command from cygwin, to see the size of the windows directory (done from an administrative command prompt - since it seemed to have some issues reading some directories otherwise)  user@comp ~ $ du -sh /cygdrive/c/windows 43G     /cygdrive/c/windows   Windows Explorer  which I understand shows it in 'base 2', (a larger unit for KB,MB,GB than base 10 KiB, MiB e.t.c.), and hence a lower quantity of that larger unit is required to give the same result.    Windows explorer shows      46.6GB  , over 50 billion bytes.    (according to windows explorer)  or  46.8GB  , over 50 billion bytes. (according to windows explorer)  So, du aside.  Even if I multiply the larger figure, 46.8GB  by 1.048576 then I get 49.0733568 that's not over 50 billion. So that's part A of the question,  but then also, part B of the question, why is the du figure so low. Continuity of analytic function implies convergence of power series? Suppose that $f(z)$ is analytic in the unit disk $\Delta:\,|z|&lt;1$. Then $f(z)$ has a Taylor series $\sum=\sum a_nz^n$ in the unit disk. One may assume that $\sum$ has $R=1$ as its radius of convergence for convenience.  Question 1 (local version):  If $f(z)$   is continous at some point, say $z=1$, on the unit circle $S^1$, then its Taylor series $\sum$  is  covergent at $z=1$?   Question 2 (global version):  Suppose that  $f(z)$   is continous on the closed unit disk $\overline\Delta$.  Is the  Taylor series $\sum$ covergent at every poin of $S^1$?   Of course, if the answer to the local version is "yes", then so is the answer to the global version.  EDIT. It seems that  Question 1 obviously has a negative answer. So I modify it into a new question.  Question 3 (New local version):  Suppose that  $f(z)$   is continous at some point, say $z=1$, on the unit circle $S^1$ and the coefficients of $\sum$ satisfies $a_n\to 0$.  Is the Taylor series $\sum$  covergent at $z=1$?   Note. If $f$ is analytic at $z=1$, then the answer to Question 3 is yes. This is Fatou's Theorem. What limitations does converting question links to links with titles have? On this  there are more than 50 links to Stack Overflow questions. However, the last 6 links aren't converted to titles (http://facebook.stackoverflow.com/questions/6530420/control-the-image-that-facebook-shows-when-i-like-a-url should be converted to ).   However:  all http://facebook.stackoverflow.com/... into http://stackoverflow.com/... fixes this, both in the preview and the final result. Also, the preview won't show any title for http://facebook.stackoverflow.com/... links.  My question is, what limitations does this converting have? How are these question titles retreived? Via API? Through database?  I'm not sure about title, feel free to edit that Does Thanos' plan apply to higher order beings? We know that Thanos' plan was to       instantly destroy half of all life in the universe    His plan doesn't appear to apply to lower or non sentient life forms      if it did half the trees in the final Wakanda scene would have disintegrated too   Does his plan apply to all beings more powerful than himself? Having trouble finding Plantera's Bulb I have been playing on hardmode for a while and have beaten the three  a couple of times. But I have yet to find a . It's getting really frustrating.  Does anyone have any methods to finding a Plantera Bulb? How can I use $variable in a shell brace expansion of a sequence? I want to use $var in a shell brace expansion with a range, in bash. Simply putting {$var1..$var2} doesn't work, so I went "lateral"...   The following works, but it's a bit kludgey.    # remove the split files echo rm foo.{$ext0..$extN} rm-segments &gt; rm-segments source rm-segments   Is there a more "normal" way? How to distinguish between gold, silver, and bronze tag badges on SEDE? IE must close for event with jQuery to work Running Windows 7  I'm trying to boost the startup speed of my computer and I'm going through "msconfig" and "services.msc" to disable some applications from starting up automatically when the computer turns on.  There are some good sites that document the entries found in the "Processes" tab of the task manager.  You can find out if they are safe to kill, who the manufacturer is, and what the process in question is used  for.  Are there any sites that list startup processes &amp;| services that are safe to kill?  For example, there is an entry in msconfig that just says "Computer Browser" - pretty vague, but seems like something to not kill.  On the other hand, there is an entry in msconfig that says "Extensible Authentication Protocol" - pretty specific and seems like it shouldn't be killed, but how can I know for sure?  Does anyone know if there are any websites documenting the "killable" items listed in both msconfig &amp; services.msc?