I got this error message 'Subscripted assignment dimension mismatch'

x=rand(16,1301);
y=rand(16,4);
k=0:0.01:1;
I=eye(size(x'*x));
b=zeros(size(x'*x));
for j=1:length(k)
    b(:,j)=(pinv(x'*x+k(j)*I)*x')*y;
end

It seems the size of b(:,j)= 1301 x 1 and the size for (pinv(x'*x+k(j)*I)*x')*y= 1301 x 4. How to write a code for output variable to get equal size? Please help.

Answer 1

[Star Strider]

This runs:

x=rand(16,1301);
y=rand(16,4);
k=0:0.01:1;
I=eye(size(x'*x));
b=zeros(size(x,2), size(y,2), size(k,2));
for j=1:length(k)
    b(:,:,j)=(pinv(x'*x+k(j)*I)*x')*y;
end

I only ran it through k=6 because it takes an excruciatingly long time. But it doesn’t throw the error. The solution was the correct preallocation of ‘b’.

[Ahmad Zul Izzi Fauzi]

Many thanks Strider. Its worked.

[Star Strider]

My pleasure.

I would save ‘b’ to a .mat file so you can load it when you need it and so you do not have to recalculate it each time.