"How to randomly select lines from a text file"

Post #302720865 by stunn3r on Wednesday 24th of October 2012 05:48:31 PM

Code:
cat file | head -n 500 | tail -n 200

A very simple idea but not for random lines.
 
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HEAD(1) 							   User Commands							   HEAD(1)

NAME
head - output the first part of files SYNOPSIS
head [OPTION]... [FILE]... DESCRIPTION
Print the first 10 lines of each FILE to standard output. With more than one FILE, precede each with a header giving the file name. With no FILE, or when FILE is -, read standard input. Mandatory arguments to long options are mandatory for short options too. -c, --bytes=[-]N print the first N bytes of each file; with the leading `-', print all but the last N bytes of each file -n, --lines=[-]N print the first N lines instead of the first 10; with the leading `-', print all but the last N lines of each file -q, --quiet, --silent never print headers giving file names -v, --verbose always print headers giving file names --help display this help and exit --version output version information and exit N may have a multiplier suffix: b 512, kB 1000, K 1024, MB 1000*1000, M 1024*1024, GB 1000*1000*1000, G 1024*1024*1024, and so on for T, P, E, Z, Y. AUTHOR
Written by David MacKenzie and Jim Meyering. REPORTING BUGS
Report head bugs to bug-coreutils@gnu.org GNU coreutils home page: <http://www.gnu.org/software/coreutils/> General help using GNU software: <http://www.gnu.org/gethelp/> COPYRIGHT
Copyright (C) 2009 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO
The full documentation for head is maintained as a Texinfo manual. If the info and head programs are properly installed at your site, the command info coreutils 'head invocation' should give you access to the complete manual. GNU coreutils 7.1 July 2010 HEAD(1)

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