[SciPy-user] howto dot(a, b.T), some a or b coords are zeros

Alan G Isaac aisaac@american....
Wed Jan 2 14:56:33 CST 2008


On Wed, 02 Jan 2008, dmitrey apparently wrote:
> I have 2 vectors a and b of shape (n, 1) (n can be 
> 1...10^3, 10^4, may be more); some coords of a or 
> b usually are zeros (or both a and b, but b is more 
> often); getting matrix c = dot(a, b.T) is required 
> (c.shape = (n,n))

Are you sure you need c explicitly?
How exactly is it used?
(I.e., what is the algebraic expression
in which c is used?)

Cheers,
Alan Isaac





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