Not as far off as you thought, now is it? -mac fanboy Show Sample Output
Searches in order of the directories of $PATH. Stops after finding the entry; looks for only that fileName. Works in Bourne, Korn, Bash and Z shells. Show Sample Output
A little bit smaller, faster and should handle files with special characters in the name.
This can be much faster than downloading one or both trees to a common servers and comparing the files there. After, only those files could be copied down for deeper comparison if needed. Show Sample Output
works on all unices. Show Sample Output
search argument in PATH accept grep expressions without args, list all binaries found in PATH Show Sample Output
better integration. works on all Unices works one bash and ksh. Show Sample Output
With this simple sed command we can easily comment and entire file.
The end of unix time and the 32bit era will be Tue Jan 19 03:14:07 UTC 2038
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date -ud @$[2**31]
date: invalid date `@2147483648'
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In 64bit you have much longer, at least to:
date -ud @$[2**55]
Sun Jun 13 06:26:08 UTC 1141709097
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Instead of looking for the right ip address, just pick whatever address you like and set a static ip mapping.
print scalar gmtime
I don't know if the --spider option works to execute a script, but it might be worth trying. Note that the Drupal project uses the following in a cron job.
wget -O - -q http://localhost/drupal/cron.php
The output is sent to standard out so it can be logged by cron.
This will calculate a running standard deviation in one pass and should never have the possibility for overflow that can happen with other implementations. I suppose there is a potential for underflow in the corner case where the deltas are small or the values themselves are small.
Define a function
vert () { echo $1 | grep -o '.'; }
Use it to print some column headers
paste <(vert several) <(vert parallel) <(vert vertical) <(vert "lines of") <(vert "text can") <(vert "be used") <(vert "for labels") <(vert "for columns") <(vert "of numbers")
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When need to pack the ZODB...
This is an on-line algorithm for calculating the mean value for numbers in a column. Also known as "running average" or "moving average".
This converts any media ffmpeg handles to flash. It would actually convert anything to anything, it's based on the file extension. It doesn't do ANY quality control, sizing, etc, it just does what it thinks is best. I needed an flv for testing, and this spits one out easily.
I have a remote php file that I want to run once an hour. I set up cron to run this wget. I don't really care about what's in the file though, I don't want to save the results, so I run the -O and send it to /dev/null
EDIT: Trolling crap removed ;)
takes approx 6 secs on a Core 2 Duo @ 2GHz, and 15 secs on atom based netbooks!
uses monoid (a,b).(x,y)=(ax+bx+ay,ax+by) with identity (0,1), and recursion relations:
F(2n-1)=Fn*Fn+F(n-1)*F(n-1)
F(2n)=(Fn+2*F(n-1))*Fn
then apply fast exponentiation to (1,0)^n = (Fn,F(n-1))
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Note that: (1,0)^-1=(1,-1) so (a,b).(1,0) = (a+b,a) and (a,b)/(1,0)=(a,b).(1,0)^-1=(b,a-b)
So we can also use a NAF representation to do the exponentiation,http://en.wikipedia.org/wiki/Non-adjacent_form , it's also very fast (about the same, depends on n):
time echo 'n=1000000;m=(n+1)/2;a=0;b=1;i=0;while(m>0){z=0;if(m%2)z=2-(m%4);m=(m-z)/2;e[i++]=z};while(i--){c=a*a;a=c+2*a*b;b=c+b*b;if(e[i]>0){t=a;a+=b;b=t};if(e[i]<0){t=a;a=b;b=t-b}};if(n%2)a*a+b*b;if(!n%2)a*(a+2*b)' | bc
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Calculates nth Fibonacci number for all n>=0, (much faster than matrix power algorithm from http://everything2.com/title/Compute+Fibonacci+numbers+FAST%2521 )
n=70332 is the biggest value at http://bigprimes.net/archive/fibonacci/ (corresponds to n=70331 there), this calculates it in less than a second, even on a netbook.
UPDATE: Now even faster! Uses recurrence relation for F(2n), see http://en.wikipedia.org/wiki/Fibonacci_number#Matrix_form
n is now adjusted to match Fn at wikipedia, so bigprimes.net table is offset by 1.
UPDATE2: Probably fastest possible now ;), uses a simple monoid operation:
uses monoid (a,b).(x,y)=(ax+bx+ay,ax+by) with identity (0,1), and recursion relations:
F(2n-1)=Fn*Fn+F(n-1)*F(n-1)
F(2n)=Fn*(2*F(n-1)+Fn)
then apply fast exponentiation to (1,0)^n = (Fn,F(n-1))
.
Note that: (1,0)^-1=(1,-1) so (a,b).(1,0) = (a+b,a) and (a,b)/(1,0)=(a,b).(1,0)^-1=(b,a-b)
So we can also use a NAF representation to do the exponentiation,http://en.wikipedia.org/wiki/Non-adjacent_form , it's also very fast (about the same, depends on n):
time echo 'n=70332;m=(n+1)/2;a=0;b=1;i=0;while(m>0){z=0;if(m%2)z=2-(m%4);m=(m-z)/2;e[i++]=z};while(i--){c=a*a;a=c+2*a*b;b=c+b*b;if(e[i]>0){t=a;a+=b;b=t};if(e[i]<0){t=a;a=b;b=t-b}};if(n%2)a*a+b*b;if(!n%2)a*(a+2*b)' | bc
Show Sample Output
commandlinefu.com is the place to record those command-line gems that you return to again and again. That way others can gain from your CLI wisdom and you from theirs too. All commands can be commented on, discussed and voted up or down.
get all pdf and zips from a website using wget
linuxswords
17
repeat a command every one second
mesuutt
11
Make vim open in tabs by default (save to .profile)
tommed
10
Which processes are listening on a specific port (e.g. port 80)
indexsmithy
1
Find files with lines that do not match a pattern
inkel
1
Convert (almost) any video file into webm format for online html5 streaming
angryunicorn
2
write text or append to a file
tomlouie
4
Search some text from all files inside a directory
zluyuer
2
Go up multiple levels of directories quickly and easily.
Tzunamii
1
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