[Python-Dev] math.areclose ...? (original) (raw)

Aahz aahz at pythoncraft.com
Sun Feb 5 19:01:24 CET 2006

On Sun, Feb 05, 2006, Alex Martelli wrote:

But pulling in the whole of Numeric just to have that one handy function is often overkill. So I was wondering if module math (and perhaps by symmetry module cmath, too) shouldn't grow a function 'areclose' (calling it just 'close' seems likely to engender confusion, since 'close' is more often used as a verb than as an adjective; maybe some other name would work better, e.g. 'almostequal') taking two float arguments and optional tolerances and using roughly the same specs as Numeric, e.g.: def areclose(x,y,rtol=1.e-5,atol=1.e-8): return abs(x-y)<atol+rtol*abs(y)

Looks interesting. I don't quite understand what atol/rtol are, though. You're right that another name would be better; almost_equal is fine.

Aahz (aahz at pythoncraft.com) <*> http://www.pythoncraft.com/

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