[Python-Dev] Re: long number multiplication

Nick Coghlan ncoghlan at iinet.net.au
Tue Dec 7 09:39:06 CET 2004

Christopher A. Craig wrote:
>>i needed to implement this myself and was thinking of storing the digits 
>>of an integer in a list.
> That's sort of what Python does except the "digits" are 15 bits,
> not base 10.  Doing it in base 10 would be a huge pain because of the
> problems with base 10->base 2 conversion.

Indeed. Python's Decimal data type stores the digits in a list for ease of power 
of 10 multiplication & rounding (the precision rules means a *lot* of that goes 
on). However, it converts that list of digits to a long integer in order to do 
addition, multiplication or division.


Nick Coghlan   |   ncoghlan at email.com   |   Brisbane, Australia

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