error: Matrix dimensions must agree / Inner matrix dimensions must agree.

Question

tevzia 2013-9-3

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/86294-error-matrix-dimensions-must-agree-inner-matrix-dimensions-must-agree

Hi, I tried to multiply two different matrix but program give me an error which is "Inner matrix dimensions must agree". here is my code:

Schedule=[1,4,3,1,1];
nstands=5;
nperiods=4;
adjacency = [0, 1, 1, 0, 1;
    1, 0, 0, 1, 0;
    1, 0, 0, 0, 0;
    0, 1, 0, 0, 0;
    1, 0, 0, 0, 0];
adj = tril(adjacency)
n=max(Schedule);
out=zeros(n);
for k=1:n
    idx=find(Schedule==k);
    out(k,idx)=1;
end
ady = sum((out * adj)') % Error using  * Inner matrix dimensions must agree.
totaladdy = sum(ady)

i tried to change it with " .* " but this time it gives : "Matrix dimensions must agree"

This code works when i use on commond window or scipts without other code. whenever i add into the main code it gives an error. I tired to create function and call it in the main code as well. like this

function [ totaladdy ] = calcaddy( schedule, adjacency )
%UNTITLED3 Summary of this function goes here
%   Detailed explanation goes here
adj = tril(adjacency);
n=max(schedule);
out=zeros(n);
for k=1:n
    idx=find(schedule==k);
    out(k,idx)=1;
end
ady = sum((out * adj)');
totaladdy = sum(ady);
end

in the main code i call function like this

[ totaladdy ] = calcaddy( breedingpopulation, adjacency );

Thank you

0 个评论
显示 -2更早的评论隐藏 -2更早的评论

请先登录，再进行评论。

请先登录，再回答此问题。

Answer 1

Walter Roberson 2013-9-3

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/86294-error-matrix-dimensions-must-agree-inner-matrix-dimensions-must-agree#answer_95770

在 MATLAB Online 中打开

Your adjacency matrix is 5 x 5. tril() of a 5 x 5 is 5 x 5.

Your Schedule has a maximum of 4, so "n" is 4. zeros(n) would be zeros(4) which would be 4 x 4.

You try to do a matrix multiplication of (5 x 5) x (4 x 4) . The second dimension of the first array, 5, does not match the first dimension of the second array, 4, so you cannot matrix multiply the two.

I would suggest

out = zeros(size(adjacency));

but leave n as max(Schedule)