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Top Forums UNIX for Dummies Questions & Answers How to randomly select lines from a text file Post 302719985 by Corona688 on Tuesday 23rd of October 2012 11:26:01 AM
Old 10-23-2012
Your time would be better spent learning awk than asking dozens of questions which could be trivially answered in it.

Code:
awk 'NR==FNR { B++; next }
(NR != FNR) && (!Z) {
        srand();
        if(B < 200) exit(1); # Too few lines
        for(N=1; N<=200; )
        {
                V=sprintf("%d", (rand()*B)+1)+0;
                if(!(V in A)) { A[V]=1; N++ }
        }
        Z=1
} NR in A' inputfile inputfile


Last edited by Corona688; 10-25-2012 at 12:34 PM.. Reason: Fixed typos
This User Gave Thanks to Corona688 For This Post:
 

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TZSELECT(8)						      System Manager's Manual						       TZSELECT(8)

NAME
tzselect - select a time zone SYNOPSIS
tzselect DESCRIPTION
The tzselect program asks the user for information about the current location, and outputs the resulting time zone description to standard output. The output is suitable as a value for the TZ environment variable. All interaction with the user is done via standard input and standard error. ENVIRONMENT VARIABLES
AWK Name of a Posix-compliant awk program (default: awk). TZDIR Name of the directory containing time zone data files (default: /usr/local/etc/zoneinfo). FILES
TZDIR/iso3166.tab Table of ISO 3166 2-letter country codes and country names. TZDIR/zone.tab Table of country codes, latitude and longitude, TZ values, and descriptive comments. TZDIR/TZ Time zone data file for time zone TZ. EXIT STATUS
The exit status is zero if a time zone was successfully obtained from the user, nonzero otherwise. SEE ALSO
newctime(3), tzfile(5), zdump(8), zic(8) TZSELECT(8)
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