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Shell arithmetic problem

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http://forums.fedoraforum.org – Hi, I'm trying to learn shell scriptig using bash and was trying to learn some basic arithmetic using variables. The script I am trying to write adds says z = x + y. I've been trying to use expr and the script is as follows: Code: x=6 y=3 z='expr x + y' echo $z When I run the script the return is expr x + y I am stuck as to why it's not running the addition and just returning the text. I've also tried z='expr $x + $y' but the return for echo $z is just expr $x + $y (HowTos)

leex's picture
Submitted by leex on 06/10/2012 – Made popular on 06/10/2012

Stories similar to Shell arithmetic problem

I need to have two variables and want to perform an addition with these variables in shell script. I am using the below script for this, but i have got expr: non-numeric argument error while running the same.

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Code: num=$1 sum=0

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I'm learning Shell scripting for a diploma in IT I'm currently doing. I'm trying to write a small script that adds two numbers as shown as in one of the tutorials we were given.

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Thanks and Regards Nanthagopal A

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