[Numpy-discussion] How to get rid of the loop?

[josef.pktd at gmail.com]

On Sat, Nov 7, 2009 at 1:51 PM, Stas K <stanconn at gmail.com> wrote:
> Can I get rid of the loop in this example? And what is the fastest way
> to get v in the example?
>
> ar = array([1,2,3])
> for a in ar:
>    for b in ar:
>        v = a**2+b**2

>>> ar[:,None]**2 + ar**2
array([[ 2,  5, 10],
       [ 5,  8, 13],
       [10, 13, 18]])

I think, for this case there is also directly a function in numpy
hypot which should also work.

Josef
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