When is min(a, b) != min(b, a)?

[Bonjour]

'NaN' means "Not a number". according to Python semantics, if you try
to compare it with any other float numbers, it should return FALSE.
just like
>>>
>>>1.0 > 'abc'
      False
>>>
Since it always return FALSE, it is not a surprise for your question.

If you wish to get infinitive number, you'd use 'inf' or '-inf', from
IEEE 754 semantics:
>>>a=float(6)
>>>b=float('inf')
>>>c=float('-inf')


Albert Hopkins wrote:
> This issue may have been referred to in
> news:<mailman.1864.1196703799.13605.python-list at python.org> but I didn't
> entirely understand the explanation.  Basically I have this:
>
>     >>> a = float(6)
>     >>> b = float('nan')
>     >>> min(a, b)
>     6.0
>     >>> min(b, a)
>     nan
>     >>> max(a, b)
>     6.0
>     >>> max(b, a)
>     nan
>
> Before I did not know what to expect, but I certainly didn't expect
> this.  So my question is what is the min/max of a number and NaN or is it
> not defined (for which I would have expected either an exception to be
> raised or NaN returned in each case).
>
> As a corrollary would I be able to rely on the above behavior or is it
> subject to change (to fix a bug in min/max perhaps :-)?