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How about adding rational fraction to Python?

Steven D'Aprano steve at REMOVE-THIS-cybersource.com.au
Sun Feb 24 17:50:17 EST 2008 
On Sun, 24 Feb 2008 11:09:32 -0800, Lie wrote:

> I decided to keep the num/den limit low (10) because higher values might
> obscure the fact that it do have limits.

You do realise that by putting limits on the denominator, you guarantee 
that the sum of the fractions also has a limit on the denominator? In 
other words, your "test" is useless.

With denominators limited to 1 through 9 inclusive, the sum will have a 
denominator of 2*3*5*7 = 210. But that limit is a product (literally and 
figuratively) of your artificial limit on the denominator. Add a fraction 
with denominator 11, and the sum now has a denominator of 2310; add 
another fraction n/13 and the sum goes to m/30030; and so on. 


-- 
Steven
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