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floating point operations in shell scripts

Terminal - floating point operations in shell scripts
echo "5 k 3 5 / p" | dc
2009-09-03 00:21:54
User: xamaco
Functions: echo
2
floating point operations in shell scripts

using bc is for sissies. dc is much better :-D

Polish notation will rule the world...

Alternatives

There are 5 alternatives - vote for the best!

Terminal - Alternatives
echo "scale=4; 3 / 5" | bc
2009-08-21 21:51:46
User: foob4r
Functions: echo
3

allows you to use floating point operations in shell scripts

bc -l <<< s(3/5)
2009-09-02 15:41:39
User: akg240
Functions: bc
3

-l auto-selects many more digits (but you can round/truncate in your head, right) plus it loads a few math functions like sin().

wcalc -q <<< '3/5'
2010-07-07 20:31:21
User: smolav
1

Calculator for shell. Similar performance and basic usage as 'bc', but with more advanced features. Not installed on most systems by default.

exp="(2+3.0)/7.0*2^2"; val=$(awk "BEGIN {print $exp}" /dev/null)
2010-03-01 02:47:22
User: JeffChen
Functions: awk
0

a simple trick to do floating point operations in shell, use awk. You can evaluate any complicated expressions which can be evaluated in C.

echo $((3.0/5.0))

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