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Jun 10th, 2008

Random number generator with awk

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I am trying to print a random line from a text file that has 10 lines. The problem that I run into is that it sometimes picks the number "0" which is not a line in the text file. How would I have it pick a random number between 1-10?

Shell Scripting Syntax (Toggle Plain Text)
#!/bin/bash
 
RANGE=10
number=$RANDOM
let "number %= $RANGE"
NAME=$(awk 'NR=='$number'{print;exit}' /home/names)
	echo "$NAME"
#!/bin/bash

RANGE=10
number=$RANDOM
let "number %= $RANGE"
NAME=$(awk 'NR=='$number'{print;exit}' /home/names)
	echo "$NAME"

Thanks to anyone who can help.

krammer

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Jun 10th, 2008

Re: Random number generator with awk

The range as it stands will run from 0 to 9
So add 1 to it, to get 1 to 10

Salem

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Posting Sage

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Jun 10th, 2008

Re: Random number generator with awk

Thanks!

Shell Scripting Syntax (Toggle Plain Text)
#!/bin/bash
 
RANGE=10
number=$RANDOM
let "number %= $RANGE"
NAME=$(awk 'NR=='$number+1'{print;exit}' /home/eric/names)
	echo "$NAME"
#!/bin/bash

RANGE=10
number=$RANDOM
let "number %= $RANGE"
NAME=$(awk 'NR=='$number+1'{print;exit}' /home/eric/names)
	echo "$NAME"

krammer

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Jun 11th, 2008

Re: Random number generator with awk

do it using awk's srand() and rand().

Shell Scripting Syntax (Toggle Plain Text)
awk 'BEGIN{
  srand()
  num=int(rand() * 10) +  1
}
NR==num' file
awk 'BEGIN{
  srand()
  num=int(rand() * 10) +  1
}
NR==num' file

ghostdog74

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