floating point bash calculator w/o precision

b(){ echo "scale=${2:-2}; $1" | bc -l; }
terms inclosing '()' must be enclosed by "" (soft quotes) bash variables must be referenced: b $x/$y ugly bracket checking (balanced, fractions...) default precision 2
Sample Output
b 6*7 -> 42
b "e(1)" 6 -> 2.718281
a=1; b=1/7; b $a/$b -> 0.14

By: dadi
2009-12-23 23:44:31

1 Alternatives + Submit Alt

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
bartonski · 536 weeks and 3 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).
dadi · 536 weeks and 3 days ago
@bartonski much of thanks, nice try.
saherteam · 311 weeks and 2 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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