[Python-ideas] PEP 485: A Function for testing approximate equality

Ron Adam ron3200 at gmail.com
Tue Jan 27 16:56:28 CET 2015

On 01/26/2015 09:08 PM, Steven D'Aprano wrote:
> Asymmetry is bad, because it is rather surprising and counter-intuitive
> that "x is close to y", but "y is not close to x". It may also be bad in
> a practical sense, because people will forget which order they need to
> give x and y and will give them in the wrong order. I started off with
> an approx_equal function in test_statistics that was symmetric, and I
> could never remember which way the arguments went.

Would it help if it was consistent order wise with other python functions 
such as is_instance?


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