[Numpy-discussion] Norm of array of vectors

[Andrey N. Sobolev]

Hi eat and Gary,

Thanks a lot for your suggestions, I've tried them in my code and
achieved similar speedup of ~270% for both of them. So I guess I'll
stick to one of those. 

Regards,
Andrey. 


> Hi,
> 
> On Thu, Mar 17, 2011 at 10:44 AM, Andrey N. Sobolev <inconnu@list.ru>
> wrote:
> 
> > Dear all,
> >
> > Sorry if that's a noob question, but anyway. I have several
> > thousands of vectors stacked in 2d array. I'd like to get new array
> > containing Euclidean norms of these vectors and get the vector with
> > minimal norm.
> >
> > Is there more efficient way to do this than
> > argmin(array([sqrt(dot(x,x)) for x in vec_array]))?
> >
> Try
> argmin(sum(vec_array** 2, 0)** 0.5)
> 
> Regards,
> eat
> 
> >
> > Thanks in advance.
> > Andrey.
> >
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