将N ^ 2个3x3矩阵级联为3Nx3N矩阵

[poster]

我有N ^ 2个矩阵。每个都是3x3矩阵。将它们串联到3Nx3N矩阵的一种方法是编写A(:,:,i)= # 3x3 matrix i=1:N^2

https://i.stack.imgur.com/podvp.png

B=[A11 A12 ..A1N;A21 ...A2N;...]但是，当N大时，是一项繁琐的工作。您提供什么？



回答：

这是一个非常快的单线 (http://www.mathworks.com/help/techdoc/ref/reshape.html) ，仅使用RESHAPE (http://www.mathworks.com/help/techdoc/ref/reshape.html)和PERMUTE (http://www.mathworks.com/help/techdoc/ref/permute.html) ：

B = reshape(permute(reshape(A,3,3*N,N),[2 1 3]),3*N,3*N).'; 并进行测试：

>> N=2; >> A = rand(3,3,N^2) A(:,:,1) = 0.5909 0.6571 0.8082 0.7118 0.6090 0.7183 0.4694 0.9588 0.5582 A(:,:,2) = 0.1791 0.6844 0.6286 0.4164 0.4140 0.5833 0.1380 0.1099 0.8970 A(:,:,3) = 0.2232 0.2355 0.1214 0.1782 0.6873 0.3394 0.5645 0.4745 0.9763 A(:,:,4) = 0.5334 0.7559 0.9984 0.8454 0.7618 0.1065 0.0549 0.5029 0.3226 >> B = reshape(permute(reshape(A,3,3*N,N),[2 1 3]),3*N,3*N).' B = 0.5909 0.6571 0.8082 0.1791 0.6844 0.6286 0.7118 0.6090 0.7183 0.4164 0.4140 0.5833 0.4694 0.9588 0.5582 0.1380 0.1099 0.8970 0.2232 0.2355 0.1214 0.5334 0.7559 0.9984 0.1782 0.6873 0.3394 0.8454 0.7618 0.1065 0.5645 0.4745 0.9763 0.0549 0.5029 0.3226

更多&回答... (https://stackoverflow.com/questions/4897989)