Matrix and vector multiplication elementwise

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Rica
Rica 2012-11-30
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 个评论
Azzi Abdelmalek
Azzi Abdelmalek 2012-11-30
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

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采纳的回答

José-Luis
José-Luis 2012-11-30
bsxfun(@times,a,h)

更多回答（4 个）

Muruganandham Subramanian
编辑：Muruganandham Subramanian 2012-11-30
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)
Wayne King
Wayne King 2012-11-30
a=[1 2 3;2 3 4;4 5 6]
h=[2 2 2];
kron(a,h)
Azzi Abdelmalek
Azzi Abdelmalek 2012-11-30
编辑：Azzi Abdelmalek 2012-11-30
a=[1 2 3;2 3 4;4 5 6]
h=[2 2 2]
out=cell2amt(arrayfun(@(x) x*h,a(:),'uni',0))
Andrei Bobrov
Andrei Bobrov 2012-11-30
编辑：Andrei Bobrov 2012-11-30
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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