max(a,b) sometimes depends on order of args about cpython HOT 6 CLOSED

Looks like a duplicate of #88536.

If math.nan is the first argument for either max() or min(), the result is always nan, regardless of the other values in the results. However, if nan is in any other position in the arguments list, the result is always what you would expect if nan was not in the arguments list.
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from cpython.

NAN per definition does equal itself, so this is the test for nan without functions. Same for other compares.

IEEE-754 says the opposite:

Any comparison with a NaN is treated as unordered.

from cpython.

yes, but this is not obvious to each python user. and python is intended to be as friendly or comfortable or easy to understand as possible. No hint in documentation?

from cpython.

yes, but this is not obvious to each python user. and python is intended to be as friendly or comfortable or easy to understand as possible. No hint in documentation?

There's already a hint in documentation: https://docs.python.org/3/library/math.html#math.nan:

Due to the requirements of the IEEE-754 standard, math.nan and float('nan') are not considered to equal to any other numeric value, including themselves.

from cpython.

I mean a hint in max(), min() docu. As not everybody ready everything. I assume many users dont even know about NAN.

from cpython.

I mean a hint in max(), min() docu. As not everybody ready everything. I assume many users dont even know about NAN.

This behaviour currently is under discussion, please read the issue found by Hugo.

from cpython.