decimal
This is an Erlang decimal arithmetic library. The code is based on https://github.com/egobrain/decimal.git, but the API was reworked to be more consistant. Also some small optimizations were added.
Build
$ rebar3 compile
How To Use
> D1 = decimal:from_binary(<<"10.22">>).
{1022,-2}
> D2 = decimal:from_binary(<<"11.245">>).
{11245,-3}
> decimal:to_binary(decimal:add(D1, D2)).
<<"21.465">>
> decimal:to_binary(decimal:sub(D1, D2)).
<<"-1.025">>
> decimal:to_binary(decimal:mul(D1, D2)).
<<"114.92390">>
> decimal:to_binary(decimal:round(half_up, decimal:mul(D1, D2), 2)).
<<"114.92">>
> decimal:to_binary(decimal:divide(D1, D2, 10)).
<<"0.90884837705">>
> decimal:to_binary(decimal:divide(D1, D2, 2)).
<<"0.90">>
> decimal:to_binary(decimal:neg(D2)).
<<"-11.245">>
> decimal:to_binary(decimal:abs(decimal:from_binary(<<"-25.3">>))).
<<"25.3">>
> decimal:cmp(decimal:from_binary(<<"10">>), decimal:from_binary(<<"34">>)).
-1
> decimal:cmp(decimal:from_binary(<<"10">>), decimal:from_binary(<<"10">>)).
0
> decimal:cmp(decimal:from_binary(<<"11">>), decimal:from_binary(<<"10">>)).
1
> decimal:to_number(D1).
10.22
> decimal:to_binary(decimal:from_number(44.21)).
<<"44.21">>
> decimal:to_binary(decimal:from_binary(<<"1000.100">>)).
<<"1000.100">>
> decimal:to_binary(decimal:normalize(decimal:from_binary(<<"1000.100">>))).
<<"1000.1">>
> decimal:to_binary(decimal:from_binary(<<"-0.00000123456">>), #{pretty => true}).
<<"-1.23456e-6">>