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Subject: timedelta and float multiplication in python 2
Date: Thu, 11 Feb 2016 11:39:25 +0100
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Xref: csiph.com comp.lang.python:102799

I ran into a problem today where I had to determine the mean point
between two datetimes. Here is an example:

>>> start =3D datetime.datetime(2016,2,11)
>>> stop =3D datetime.datetime.now()
>>> mean =3D 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=3D0.5*((stop-start).total_seconds(=
)))
datetime.datetime(2016, 2, 11, 5, 45, 45, 818009)

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