清空筛选条件
清空筛选条件

Fastest way to multiply each block of an array with another matrix

1 次查看（过去 30 天）
Mnr
Mnr 2015-12-23
评论： Mnr 2015-12-23
Hello all,
I have a 12x4xN array which I would like to multiply each 12x4 block by a 4x16 matrix in order to get a 12x16xN array. Could somebody please help me with a fast way of doing that? Thank you!

请先登录，再回答此问题。

采纳的回答

James Tursa
James Tursa 2015-12-23
编辑：James Tursa 2015-12-23
If you have a C compiler:
A = your 12 x 4 x N array;
B = your 4 x 16 matrix;
out = mtimesx(A,B);
You can find mtimesx here:
http://www.mathworks.com/matlabcentral/fileexchange/25977-mtimesx-fast-matrix-multiply-with-multi-dimensional-support
If you don't have a C compiler, then you can try MULTIPROD:
http://www.mathworks.com/matlabcentral/fileexchange/8773-multiple-matrix-multiplications--with-array-expansion-enabled
  1 个评论
Mnr
Mnr 2015-12-23
Thank you! I did it using mltiprod and it is perfect. Can I know what is the best way to install the C compiler as well?

请先登录，再进行评论。

更多回答（1 个）

Andrei Bobrov
Andrei Bobrov 2015-12-23
Let A - your array with size [12x4xN]
B - matrix 4x16
sa = size(A);
sb = size(B);
out = zeros([sa(1),sb(2),sa(3)]);
for jj = 1:sa(3)
out(:,:,jj) = A(:,:,jj)*B;
end

类别

在 Help Center 和 File Exchange 中查找有关 Data Types 的更多信息

标签

Community Treasure Hunt

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

Start Hunting!

Translated by