Matrix and vector multiplication elementwise
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I have a big matrix and vector. itry to present my problem with this exemple:
%
a=[1 2 3;2 3 4;4 5 6]
h=[2 2 2]
how to calculate:
%
C=[a(1,1)*h(1) a(1,1)*h(2) a(1,1)*h(3); a(2,1)*h(1) a(2,1)*h(2) a(2,2);.......;...;a(3,3)*h(1) a(3,3)*h(2) a(3,3)*h(3)]:
?
Thank you
1 Comment
Azzi Abdelmalek
on 30 Nov 2012
The answer you've accepted don't answer your question, the size of your matrix
C=[a(1,1)*h(1) a(1,1)*h(2) a(1,1)*h(3); a(2,1)*h(1) a(2,1)*h(2) a(2,2);.......;...;a(3,3)*h(1) a(3,3)*h(2) a(3,3)*h(3)]:
is 9x3 while José-Luis result is 3x3
Accepted Answer
More Answers (4)
Muruganandham Subramanian
on 30 Nov 2012
Edited: Muruganandham Subramanian
on 30 Nov 2012
hi,
a=[1 2 3;2 3 4;4 5 6];
h=[2 2 2];
for i=1:3
for j=1:3
c(i,j)=a(i,j)*h(i);
end
end
disp(c)
0 Comments
Azzi Abdelmalek
on 30 Nov 2012
Edited: Azzi Abdelmalek
on 30 Nov 2012
a=[1 2 3;2 3 4;4 5 6]
h=[2 2 2]
out=cell2amt(arrayfun(@(x) x*h,a(:),'uni',0))
0 Comments
Andrei Bobrov
on 30 Nov 2012
Edited: Andrei Bobrov
on 30 Nov 2012
Rica wrote: "...how to calculate: ...
C=[a(1,1)*h(1) a(1,1)*h(2) a(1,1)*h(3); a(2,1)*h(1) a(2,1)*h(2) a(2,2);.......;...;a(3,3)*h(1) a(3,3)*h(2) a(3,3)*h(3)]: ..."
out = reshape(bsxfun(@times,reshape(a,1,size(a,1),[]),h(:)),numel(h),[])';
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