How to convert 3D matrix to 2D with a specific format

Hello all :)

I have a [1000,64,10] matrix and want to change it to a [10000,64] in a way that the first 1000 rows in 2D matrix belong to [:,:,1] in 3D matrix and the 2nd 1000 rows to [:,:,2] and so on, in other words I want the element (1001,1) in the new matrix corresponds to (1,1,2) in the old one and (2001,1) corresponds to (1,1,3) and so on.

Is there any function applying this rule?

Thanks :)

Answer 1

[Azzi Abdelmalek]

A=rand(1000,64,10);
B=permute(A,[ 2 1 3]);
out=B(:,:)'

[RH]

Dear Azzi

Thanks for the quick response!

I saw the same approach in the forum else where and if I'm not mistaken it was you who had recommended it, so I checked the "permute" function and given the examples I thought it just reorders dimensions while keeping the total dimension unchanged.

Now it seems that my reasoning was wrong, would you please clarify how your script converts [1000,64,10] to [10000,64] by the specific format I requested?

Cheers

[Azzi Abdelmalek]

Let us take short example

A(:,:,1)=[1 2;3 4;5 6];
A(:,:,2)=[10 20;30 40;50 60]
A(:,:,3)=[100 200 ;300 400;500 600]

A(:,:,1) =

     1     2
     3     4
     5     6

A(:,:,2) =

    10    20
    30    40
    50    60

A(:,:,3) =

   100   200
   300   400
   500   600

B=permute(A,[ 2 1 3])

B(:,:,1) =

     1     3     5
     2     4     6

B(:,:,2) =

    10    30    50
    20    40    60

B(:,:,3) =

   100   300   500
   200   400   600

B(:,:)'

ans =

     1     2
     3     4
     5     6
    10    20
    30    40
    50    60
   100   200
   300   400
   500   600

[RH]

Dear Azzi

Thanks again :)

So what I had neglected was that you transposesd the 3D array * (:,:) *, such a useful application to know :D

Cheers

[Azzi Abdelmalek]

RH, I posted a short example, I think my code is doing what you asked. If not, please, post the expected result from my short example

[RH]

Dear Azzi

It does exactly what I was looking for... Thanks again! :)

Chears

Answer 2

[Andrei Bobrov]

A = randi(100,3,4,4);

a1 = num2cell(A,[1 2]);
out = cat(1,a1{:});

or

out = reshape(permute(A,[1 3 2]),[],size(A,2));

[RH]

Dear Andrei

Thanks for the help, I'm going to check it too, it's always handy to know different solutions. :)

Cheers