while true; do read i; echo $[$i]; done

Simple calculator

The $[...] block in bash and zsh will let you do math. echo $[6*7] This is the same as using $((...)), which also works in ksh. Of course, this is a simple, dumb wrapper and doesn't allow floating-point.
Sample Output
6*7
42
30-7
23
(9+3)**2
144
^C

0
By: mulad
2009-02-18 23:13:09

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What Others Think

Please use command "bc". Thanks.
gniourf_gniourf · 482 weeks and 5 days ago
Yeah, the calculator is actually a silly thing. The intent was to show something useful for $[...]
mulad · 482 weeks and 5 days ago

What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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