How can I apply arrayfun with 2D matrix inputs?

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I want to accelerate the following code.
B=zeros(N,M,M);
for n=1:N
B(n,:,:)=inv(A(n,:,:));
end
where the size of A is N x M x M. Arrayfun doesn't support such a matrix input. So I would like to know the way to accelerate it.
Thank you in advance!
  2 Comments
Andrei Bobrov
Andrei Bobrov on 26 Jun 2017
Edited: Andrei Bobrov on 26 Jun 2017
It is unlikely that the arrayfun will accelerate.
Daichi
Daichi on 26 Jun 2017
Thank you. I see. Is there any way to handle this kind of processing?

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Accepted Answer

Andrei Bobrov
Andrei Bobrov on 26 Jun 2017
Edited: Andrei Bobrov on 26 Jun 2017
B = permute(A,[2,3,1]);
eye3 = eye(3);
for jj = 1:size(B,3)
B(:,:,jj) = B(:,:,jj)\eye3;
end
B = permute(B,[3,1,2]);
or within cellfun:
B = permute(cell2mat(cellfun(@(x)x\eye(3),...
num2cell(permute(A,[2,3,1]),[1,2]),'un',0)),[3,1,2]);
  2 Comments
Daichi
Daichi on 26 Jun 2017
Edited: Daichi on 26 Jun 2017
I see that cellfun is available in this case. But I eventually found that this kind of processing cannot be accelerated even if we use cellfun as you described. I guess num2cell and cell2mat may require some computational costs. Fortunately, the first one using backslash operator was faster. Anyway, thank you so much for your kind answer.
Andrei Bobrov
Andrei Bobrov on 26 Jun 2017
Within arrayfun:
B = permute(A,[2,3,1]);
Bc = arrayfun(@(ii)B(:,:,ii)\eye(3),reshape(1:size(B,3),1,1,[]),'un',0);
B = permute(cell2mat(Bc),[3,1,2]);

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