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floating point bash calculator w/o precision

Terminal - floating point bash calculator w/o precision
b(){ echo "scale=${2:-2}; $1" | bc -l; }
2009-12-23 23:44:31
User: dadi
Functions: bc echo
0
floating point bash calculator w/o precision

terms inclosing '()' must be enclosed by "" (soft quotes)

bash variables must be referenced: b $x/$y

ugly bracket checking (balanced, fractions...)

default precision 2

Alternatives

There is 1 alternative - vote for the best!

Terminal - Alternatives
calc() { awk 'BEGIN { OFMT="%f"; print '"$*"'; exit}'; }

Know a better way?

If you can do better, submit your command here.

What others think

I think that I would rather sacrifice the ability to set precision in order to leave the quotes out of the arguments.

calc(){ echo "scale=2; $*" | bc -l; }

Alternatively, you could have a $PRECISION environment variable that you could set independently:

calc(){ echo "scale=${PRECISION:-2}; $*" | bc -l; }

if $PRECISION is unset:

b 3/8

.37

PRECISION=5 b 3/8

.37500

Comment by bartonski 247 weeks and 5 days ago

Thanks for thinking about, bartonski.

But it's intended for fast calculating some stuff or for using in a script, so I find an extra variabale for precision a little bit oversized.

The quotes are needed only in case of using brackets, not due to the number of args (see samples).

Comment by dadi 247 weeks and 5 days ago

@bartonski

much of thanks,

nice try.

Comment by saherteam 22 weeks and 3 days ago

Your point of view

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