[Numpy-discussion] Multiplying numpy floats and python lists
Tony S Yu
tsyu80@gmail....
Sun Jun 20 12:56:48 CDT 2010
I came across some strange behavior when multiplying numpy floats and python lists: the list is returned unchanged:
> In [18]: np.float64(1.2) * [1, 2]
>
> Out[18]: [1, 2]
On the other hand, multiplying an array scalar and a python list gives the expected answer
> In [19]: np.array(1.2) * [1, 2]
>
> Out[19]: array([ 1.2, 2.4])
Finally, multiplying a python float and a python list gives an error:
> In [20]: 1.2 * [1, 2]
> ---------------------------------------------------------------------------
> TypeError Traceback (most recent call last)
>
> /Users/Tony/<ipython console> in <module>()
>
> TypeError: can't multiply sequence by non-int of type 'float'
These last two results (with the array scalar and the python float) both seem appropriate, but the numpy-float behavior is surprising. Is this a bug?
-Tony
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