rational numbers

[Schüle Daniel]

Hello NG,

recently I was using Scheme and Ruby and was really nicely surprised
to find there support for the computing with rational numbers

for example this how it works in Ruby

mond:/pool/PROG/ruby # irb
irb(main):001:0>
irb(main):002:0* require "mathn"
=> true
irb(main):003:0> r = Rational(1,3)
=> 1/3
irb(main):004:0> p = Rational(1,5)
=> 1/5
irb(main):005:0> r+p
=> 8/15
irb(main):007:0> (r+p)**2
=> 64/225
irb(main):008:0>

does anybody know modules which make rational numbers available?
and are there considerations to add them to the core, like
complex numbers (maybe in Python 3)

Regards, Daniel

[Paul Rubin]

Schüle Daniel <uv**@rz.uni-karlsruhe.de> writes:

does anybody know modules which make rational numbers available?
Try gmpy.mpq (google for gmpy).
and are there considerations to add them to the core, like
complex numbers (maybe in Python 3)

I don't think it's been discussed much.

[Paul Rubin]

Schüle Daniel <uv**@rz.uni-karlsruhe.de> writes:

does anybody know modules which make rational numbers available?
and are there considerations to add them to the core, like
complex numbers (maybe in Python 3)

I think it's not likely. In Scheme, (/ 5 2) is the rational number
5/2, while in current Python, 5/2 is the integer 2. If Python got
native rationals, we'd expect something similar. But it's been
publicly announced that in Python 3, 5/2 will be the floating point
number 2.5.

[Carsten Haese]

On Tue, 2006-01-17 at 11:22, Paul Rubin wrote:

Schüle Daniel <uv**@rz.uni-karlsruhe.de> writes:

does anybody know modules which make rational numbers available?

Try gmpy.mpq (google for gmpy).

and are there considerations to add them to the core, like
complex numbers (maybe in Python 3)

I don't think it's been discussed much.

Somebody must have discussed it. There is a rejected PEP for adding a
Rational type to python:

http://www.python.org/peps/pep-0239.html

-Carsten