# [Edu-sig] Kirby Urner's Sieve of Eratosthenes

**Dustin James Mitchell
**
djmitche@midway.uchicago.edu

*Thu, 8 Jun 2000 14:33:06 -0500 (CDT)*

On Mon, 5 Jun 2000, Kirby Urner wrote:
>* PS: Dustin, would your agree that reduce(mul,terms) and
*>* reduce(add,terms) are a useful way to introduce sums and
*>* products, corresponding to geeky greek symbols capital
*>* SIGMA and capital PI. In other words:
*>*
*>* from operator import mul,add
*>*
*>* def sum(terms):
*>* """Same as SIGMA (terms is a list)"""
*>* return reduce(add,terms)
*>*
*>* def product(terms):
*>* """Same as PI (terms is a list)"""
*>* return reduce(mul,terms)
*>*
*>* Would these be useful as "math through programming"
*>* Python definitions?
*>*
*>* Note: n! would be the same as product( range(1,n+1) ).
*
I like this, and it's extremely compact, but I would start by simply using
sum() and product() as black-box operators, and only delving into their
implementation a little bit later (but still before using filters).
Dustin
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|* Dustin Mitchell )O( |
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