How can i vectorize a matrix multiplication of higher dimension arrays?

3 Ansichten (letzte 30 Tage)
I want to multiply a 6x6 matrix A and a 6x1 vector B at every grid point in a 3D earth model. Currently I am doing this:
for ix=1:length(x)
for iy=1:length(y)
for iz=1:length(z)
C(:,ix,iy,iz)=squeeze(A(:,:,ix,iy,iz))*squeeze(B(:,ix,iy,iz));
end
end
end
Is there a way to vectorize this? Currently this segment of nested loops is by far the slowest part of my code (almost 90% of the time taken every iteration is spent in this nested loop). Thanks!
  1 Kommentar
Anthony Barone
Anthony Barone am 1 Apr. 2016
I have found an answer, but I still wanted to post it incase anyone else has a similiar situation. I did this:
for n=1:6
C(n,:,:,:)=sum(squeeze(A(n,:,:,:,:)).*B);
end
For me, this method proved to be ~30x faster than my initial method.

Melden Sie sich an, um zu kommentieren.

Antworten (2)

Steven Lord
Steven Lord am 17 Sep. 2020
If you're using release R2020b or later, take a look at the pagemtimes function introduced in that release.

Matt J
Matt J am 1 Apr. 2016
Using mtimesx ( Download )
C=mtimesx( reshape(A,6,6,[]) , reshape(B,6,1,[]) );
C=reshape(C,size(B));

Kategorien

Mehr zu Operating on Diagonal Matrices finden Sie in Help Center und File Exchange

Produkte

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by