Re: LARGE numbers

Tuvas [EMAIL PROTECTED] writes: I've been thinking about writing a program to generate the world's largest prime numbers, just for the fun of it. This would require being able to hold an 800 digit number into memory (25 megabits, or a little over 3 megs of memory for just one variable...)

Re: LARGE numbers

[EMAIL PROTECTED] wrote: An early alpha-quality release is available at http://home.comcast.net/~casevh/ Given the module named Decimal in Python 2.4, I'd suggest you to rename your library. -- Giovanni Bajo -- http://mail.python.org/mailman/listinfo/python-list

Re: LARGE numbers

Already done for next version. Tentatively, there will be a package called ar (Arbitrary Radix) and the module will be called BigInt. I'm also working on an arbitrary radix BigFloat module. Case -- http://mail.python.org/mailman/listinfo/python-list

Re: LARGE numbers

[EMAIL PROTECTED] wrote: ... Python does support large numbers, but it's not very fast for such large numbers. There is a Python module called GMPY that uses the GMP (Gnu Multiple Precision) library for faster operations on large numbers. As the author of gmpy, I'd like to point out that

Re: LARGE numbers

[EMAIL PROTECTED] (Alex Martelli) writes: As the author of gmpy, I'd like to point out that the speed difference isn't all that large, if all you're doing is ordinary arithmetic -- a few times at most (it can be better if you need some of GMP's functionality which gmpy exposes, such as

Re: LARGE numbers

Paul Rubin wrote: [EMAIL PROTECTED] (Alex Martelli) writes: For numbers of this size, won't gmpy use FFT-based multiplication? That's potentially orders of magnitude faster than ordinary n**2 multiplication. But Python is no slouch with its use of Karatsuba multiplication. (in other words,

Re: LARGE numbers

Paul Rubin wrote: [EMAIL PROTECTED] (Alex Martelli) writes: As the author of gmpy, I'd like to point out that the speed difference isn't all that large, if all you're doing is ordinary arithmetic -- a few times at most (it can be better if you need some of GMP's functionality which gmpy

Re: LARGE numbers

[EMAIL PROTECTED] writes: Python's native longs use Karatsuba multiplication with is O(n^1.585). My early version of DecInt (BigDecimal) uses 4-way Toom-Cook ... Wow, cool! Thanks. -- http://mail.python.org/mailman/listinfo/python-list

Re: LARGE numbers

Well, as I'll be doing lots of multiplication, guess that GMPY is the way to go. I'll use DecInt only for converting to strings if I find anything interesting. This is all just kind of a theoretical aproach, but, it can be lots of fun. Who knows if Python'll help find the largest prime number

Re: LARGE numbers

For more information on how the largest prime number was found, see www.mersenne.org. Python does support large numbers, but it's not very fast for such large numbers. There is a Python module called GMPY that uses the GMP (Gnu Multiple Precision) library for faster operations on large numbers.