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Feb
24
comment How do you derive a decimal from a math operation involving a variable?
bash only does integer math. Just use awk and be done in one line: awk '{sum += $4} END {print 10^5/sum}' $f
Feb
24
comment Ubuntu installaion doesn't ask for boot loader
What version of Ubuntu and which install method / image did you use? What options did you choose during the install? If the system installed and boots successfully it's not really a problem, is it?
Feb
24
comment the timezone format in /etc/timezone of debian7
UTC is not a location, so it is a special case and goes into Etc.
Feb
10
comment Write bash function which operates on list of filenames
I don't think that is proper scp syntax. You can't do user@host:"file list" as far as I am aware. You need to repeat user@host for each file.
Jan
31
comment What does . ~/.bashrc command do?
pubs.opengroup.org/onlinepubs/9699919799/utilities/…
Jan
27
comment Run another command before running the command the user wants to run
@IonicăBizău The reason there is no infinite recursion is given in the bash manual: The first word of the replacement text is tested for aliases, but a word that is identical to an alias being expanded is not expanded a second time. This means that one may alias ls to "ls -F", for instance, and Bash does not try to recursively expand the replacement text
Jan
23
comment Increment Numbers in URL?
What are you really trying to do? If you just want to print a list with bash: for i in {192..302}; do echo "http://sample.com/poilus/cwrgshs/$i/$i.html"; done. I smell an XY problem though.
Jan
23
comment In a Bash if condition, how to check whether any files matching a simple wildcard expression exist?
Your answer is different from @ChrisDown's because you parse ls output whereas he does not (he only checks its exit status). Due to the complexities involved with parsing ls output, the fact that ChrisDown avoids it entirely makes his answer more robust and correct than yours, even if yours will work in the many cases where "reasonable" file names (i.e. not containing whitespace) are concerned.
Jan
14
comment Vim colors conflicting with terminal ones
As vim runs in a 256 color terminal it will be limited to the 256 colors the terminal uses, and there is no full RGB terminal I am aware of so @al92's suggestion is unlikely to be possible. The closest you can get is to come up with a scripted command to change terminal colors and arrange to have it run every time you open and close vim to set and reset the terminal colors.
Jan
8
comment Bash: kill background jobs
@fersarr Here you go
Dec
27
comment How do I get the old `du` behaviour back?
Have you considered du -c?
Dec
19
comment sudo - ubuntu 12.04
Are you sure you aren't in the sudo or admin group? Maybe there is something in /etc/sudoers.d?
Dec
17
comment awk manipulation of file
@user3138373 It's just a tab to separate gene and coord into separate columns.
Dec
16
comment awk array using number as value did not work
@Karli Update your question. You said you corrected your code so update your question and then provide more information about the problem.
Dec
16
comment awk array using number as value did not work
If the reference file is missing a column in some rows then your reference file is broken and you should fix the file. Go type in a 0 for every missing number.
Dec
16
comment awk array using number as value did not work
Your awk code does not match your English description. According to your English description of your desired output, you should have if ($1 in a) $2 = a[$1]; print and for the second part if ($1 in b) $3 = b[$1] + $3 - 1; $4 = b[$1] + $4 - 1; print.
Dec
12
comment How can I run a command in bash after any change in $PWD?
Commands external to the shell can never change the shell's working directory so you won't have to worry about those, only built-ins.
Dec
11
comment Gmail blocking mutt
Do you have 2-factor authentication turned on in gmail? If so mutt won't be able to log in that way. You'll have to generate an application key for mutt to use to log in instead.
Dec
11
comment Storing longer text output in memory in shell variables vs Writing to disk
@CuneyitKiris That is an interesting link and quite a long one. Would you care to elaborate as to why you want me to look at it? Like I said, your answer not really address the question at all. There is nothing to put in the environment or argument list here. I don't see how your suggestion of "write a C program that writes data" is relevant or helpful.
Dec
11
comment Storing longer text output in memory in shell variables vs Writing to disk
@dbza Since you have edited your question to show the entire loop, I would recommend moving >>log_file.txt outside the loop, so you have done<infile >>log_file.txt as the last line instead. That way you keep the file open and avoid reopening and reclosing it each iteration. If you want to try anything more complicated though, you should first take measurements to see if disk I/O is really taking enough time to be worth optimizing. You can probably do this by replacing >>log_file.txt with >/dev/null to get rid of disk I/O altogether and see how much of a speed-up you get.