NumPy loop efficiency

Konrad Hinsen hinsen at cnrs-orleans.fr
Fri Mar 30 12:27:18 CEST 2001


"Sébastien de Menten" <sdementen at hotmail.com> writes:

> I was wondering if writing the following statement with NumPy arrays z,a,b
> and c:
> z = a + b + c

Two loops plus creation of a temporary array.

> And if
> a[:]=cos(a)+sin(a)
> creates temporary variables or assigns directly the result (like
> a[i]=cos(a[i])+sin(a[i])

It does create a temporary array. Getting rid of this would be a lot
of work, array expressions would have to use lazy evaluation.
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