BASH Arithmetic Expressions

Posted by Arko on Stack Overflow See other posts from Stack Overflow or by Arko
Published on 2010-03-25T17:07:50Z Indexed on 2010/03/25 17:13 UTC
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Filed under:

bash

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arithmetic

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floating-point

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expressions

I had used several ways to do some simple integer arithmetic in BASH (3.2). But I can't figure out the best (preferred) way to do it.

result=`expr 1 + 2`
result=$(( 1 + 2 ))
let "result = 1 + 2"

What are the fundamental differences between those expressions?
Is there other ways to do the same?

Is the use of a tool like bc mandatory for floating point arithmetic?

result=`echo "7/354" | bc`

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