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

Robert Kern robert.kern@gmail....
Tue Dec 8 18:52:26 CST 2009

2009/12/8  <alan@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.

Robert Kern

"I have come to believe that the whole world is an enigma, a harmless
enigma that is made terrible by our own mad attempt to interpret it as
though it had an underlying truth."
  -- Umberto Eco

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