Re: sparse matrix operators

[David Bateman]

I fail to see why you need an oct-file or something special for what
you want. Consider the code

n = 10;
p = 0.2;
a = sprand(n,n,p);
b = sprand(n,n,p);

## This version does a full matrix multiply and then extracts the diagonal
c = diag(a * b, 0);

## This version only multiplies the diagonal
d = sum(a .* b',2);

## Compare the two results and see they are the same
assert(c,d)

That does exactly what you want. I.E. calculate only the matrix multiply
on the diagonal..

Regards
David


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David Bateman                                address@hidden
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