Error using *

[FrankDeussens]

Hey!
I am recieving the following error very frequently:

"Error using *
Incorrect dimensions for matrix multiplication. Check that the number of columns in the first matrix matches the
number of rows in the second matrix. To perform elementwise multiplication, use '.*'.

Error in TSEMO_V4>hypervolumemonte (line 633)
P=P*diag(1./r);
..."

Any idea how to fix this? Let me know if further elaboration is requiered.

[Protoplanetary-Fish]

I've not encoutered that error.

But I would recommend everyone to use this vectorized version of that function (if compatible with your MatLab version). It should be around 12-20x faster (at the cost of a bit of memory) than the one in the original codebase as it is a bottleneck on execution speed if you are pushing the algorithm.

function v = hypervolumemonte(P,r,N)

% Check input and output
narginchk(2,3);
nargoutchk(0,1);

P=P*diag(1./r);
[~,d]=size(P);

if nargin<3
    N=1000;
end
if ~isscalar(N)
    C=N;
    N=size(C,1);
else
    C=rand(N,d);
end

C_expanded = permute(C, [1 3 2]);
P_expanded = permute(P, [3 1 2]);
domination_checks = all(C_expanded > P_expanded, 3);
fDominated = any(domination_checks, 2);

v=sum(fDominated)/N;
return