[Numpy-discussion] Can't set an element of a subset of an array, , ,

[alan at ajackson.org]

>2009/12/8  <alan at ajackson.org>:
>> Okay, I'm stuck. Why doesn't this work?
>>
>> In [226]: mask
>> Out[226]: array([False, False, False, ..., False, False, False], dtype=bool)
>> In [229]: mask[data['horizon']==i][2] = True
>
>mask[data['horizon']==i] creates a copy. mask[data['horizon']==i][2]
>assigns to the copy, which then gets thrown away.
>

Bummer. That was such a nice way to reach inside the data structure.


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