On Sun, Oct 18, 2020 at 03:26:11AM -0400, Wes Turner wrote:

> assert math.inf**0 == 1
> assert math.inf**math.inf == math.inf

Wes, I don't understand what point you are trying to make here. Are you 
agreeing with that behaviour? Disagreeing? Thought it was so surprising 
that you can't imagine why it happens? Something else?

If you find a behaviour which is forbidden or contradicted by the 
documentation, then you should report it as a bug, but just 
demonstrating what the behaviour is with no context isn't helpful.

Please remember that the things which are blindingly obvious to you 
because you just thought them are not necessarily obvious to those of us 
who aren't inside your head :-)

Python's float INFs and NANs (mostly?) obey the rules of IEEE-754 
arithmetic. Those rules are close to the rules for the extended Real 
number line, with a point at both positive and negative infinity.

These rules are not necessarily the same as the rules for transfinite 
arithmetic, or the projective number line with a single infinity, or 
arithmetic on cardinal numbers, or surreal numbers.

Each of these number systems have related, but slightly different, 
rules. For example, IEEE-754 has a single signed infinity and 2**INF is 
exactly equal to INF. But in transfinite arithmetic, 2**INF is strictly 
greater than INF (for every infinity):

    2**aleph_0 < aleph_1
    2**aleph_1 < aleph_2
    2**aleph_2 < aleph_3

and so on, with no limit. There is no greatest aleph, there is always a 
larger one.

Do you have a concrete suggestion you would like to make for a change or 
new feature for Python? If not, I suggest that this thread is going 
nowhere.


-- 
Steve
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