[Python-ideas] numerical type combining integer and float/decimal properties [Was: Re: Python Numbers as Human Concept Decimal System]

[Chris Angelico]

On Tue, Mar 11, 2014 at 7:57 AM, Ethan Furman <ethan at stoneleaf.us> wrote:
> I think he's saying make a new type similarly to complex, only instead of
> two floats to make a complex number, have a (long) int and a decimal float
> to make this new type.  The long int portion would have infinite precision,
> the float portion would have, say, 16 digits (or whatever).

That's plausible as a representation, and looks tempting, but basic
arithmetic operations become more complicated. Addition and
subtraction just need to worry about carries, but multiplication forks
out into four multiplications (int*int, int*frac, frac*int,
frac*frac), and division becomes similarly complicated. Would it
really be beneficial?

ChrisA