# Reshape a matrix dimension

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DM on 3 Feb 2017
Commented: Jonah Pearl on 2 Sep 2020
I have a matrix A which has dimension 1320 x14x4 and I would like to make it a matrix of dimension 12x110x14x4. I know I should use the
reshape
but now sure sure how to use it.

the cyclist on 3 Feb 2017
Edited: the cyclist on 3 Feb 2017
reshape(A,[12,110,14,4])
You should be careful that the elements are being reordered in the order you intend. MATLAB is going to read down the 1st column, then the 2nd column, etc, and then go to the next "plane" along the 3rd dimension.
Depending on what order you actually want, you may need to sneak a transpose in there.
Stephen23 on 3 Feb 2017
Transpose is not defined for ND arrays. It would have to be permute.
the cyclist on 3 Feb 2017
Yes, sorry, I just meant transpose in the math sense! Agreed that the permute function might be needed.

Stephen23 on 3 Feb 2017
Edited: Stephen23 on 3 Feb 2017
reshape(A,12,110,14,4)
and you might need permute too.
MATLAB has excellent documentation online, which is free for anyone to read. I just used [famous search engine] and this was the very first result:
The documentation even explains what it does, what the required inputs and outputs are, and gives complete working examples! We don't have to guess how MATLAB works, because the documentation tell us.
Jonah Pearl on 2 Sep 2020
The MATLAB documentation is prettt sparse for reshape...the closest thing to an explanation about OP's question (which I also have) is " The elements in B also maintain their columnwise order from A." There's nothing helpful on multi-dimensional reshaping. But I agree that we can just mess around.