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From: Peter Otten <__peter__@web.de>
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Subject: Re: timedelta and float multiplication in python 2
Date: Thu, 11 Feb 2016 12:24:20 +0100
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Xref: csiph.com comp.lang.python:102803

Nagy László Zsolt wrote:

> I ran into a problem today where I had to determine the mean point
> between two datetimes. Here is an example:
> 
>>>> start = datetime.datetime(2016,2,11)
>>>> stop = datetime.datetime.now()
>>>> mean = start + (stop-start)*0.5
> Traceback (most recent call last):
>   File "<stdin>", line 1, in <module>
> TypeError: unsupported operand type(s) for *: 'datetime.timedelta' and
> 'float'
> 
> A workaround could be something like this:
> 
>>>> start + datetime.timedelta(seconds=0.5*((stop-start).total_seconds()))
> datetime.datetime(2016, 2, 11, 5, 45, 45, 818009)

How about

mean = start + (stop - start) / 2

?
 
> Interesting thing is that total_seconds() already returns fractions of
> seconds, so it would be almost trivial to implement timedelta
> multiplication with floats.
> 
> I have checked and it does work with Python 3. But it does not work with
> Python 2 - is there a good reason for this?
> 
> Thanks,
> 
>    Laszlo