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Creating Matrix using two vectors and scalar

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jack
jack on 17 Dec 2015
Commented: jack on 18 Dec 2015
Hi guys,
I need your help in solving the following problem: Given a row vector, a column vector and an index create a matrix in the following manner (look at example) without using cell arrays and the implementation should be fast:
Remark: "index" correspond to the row column!
Thanks in advance.
  5 Comments
jack
jack on 18 Dec 2015
Thank you very much, i have solved it using repmat.

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Answers (2)

Andrei Bobrov
Andrei Bobrov on 17 Dec 2015
function out = fun1(r,c,ii)
out = ones(numel(c),1)*r;
out(:,ii) = c;
end
use
r = [2 7 3 5];
c = [2;7;10];
ii = 2;
out = fun1(r,c,ii);

Kirby Fears
Kirby Fears on 17 Dec 2015
jack,
Please read the repmat() documentation to understand its interface and functionality. With repmat, you can stack copies of your row vector into a matrix.
You should be able to determine how many copies of your row vector to stack based on the length() or size() of your column vector.
From there, you just have to insert the column vector into the appropriate column using array indexing .

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