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Unix random number generate in given range


 
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# 1  
Old 07-22-2011
Unix random number generate in given range

Hi All,

I have extracted some report from database for few activities done.

Now I have a requirement to add some random time(In range of 10-35) in front of each activity.

Can be generated random numbers in any bash/sh shell within a given number range, let's say in between 10-30.

Could you please help me.
# 2  
Old 07-22-2011
Have a look at
Code:
 $RANDOM

Manipulate it a bit to get numbers b/w 10 and 30
# 3  
Old 07-22-2011
Panyam, thanks for revert, but how do I manipulate it ? any suggestion ?
# 4  
Old 07-22-2011
Code:
 
echo "10+$RANDOM%10*(2)+2 " | bc 
 
will generate random numbers in 12~30 range, if that suffice.

This User Gave Thanks to panyam For This Post:
# 5  
Old 07-22-2011
Thanks Panyam for your useful & quick help, this is what I wanted to do. :-)
# 6  
Old 07-23-2011
You can use also builtin calculation, tested using ksh and bash
Code:
echo $(( 10+RANDOM%21 ))
# or more generic
min=10
max=30
((diff=max-min+1))
echo $(( min + RANDOM%diff ))

This User Gave Thanks to kshji For This Post:
# 7  
Old 07-23-2011
Hi.
Code:
shuf -i 10-30 -n 1

produces, in 3 separate runs:
Code:
26
% shuf -i 10-30 -n 1
15
% shuf -i 10-30 -n 1
25

The shuf utility is part of GNU coreutils, Coreutils - GNU core utilities which you could download, configure, compile, etc., if your system does not have coreutils installed or available via your package manager -- easier for Linux than for one of the Unix systems, Solaris, *BSD, etc.

Many features, see on-line man page is at: shuf(1): make random permutations - Linux man page

Best wishes ... cheers, drl

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