reshape a 3d matrix into 2d

Hello, Im trying to convert a 3d matrix x(9,9,625) into a 2d x2(225,225) .

I want to put each (:,:,i) of x in order for the first 25 chunks and then change 'col' in the 3d.

for example if x (:,:,1) was [1,2,3 x(:,:,2) = [7,8,9 x(:,:,3) = [13,14,15 x(:,:,4) = [19,20,21

4,5,6] 10,11,12] 16,17,18] 22,23,24]

then x2 would be x2 = [1,2,3, 7,8,9

4,5,6, 10,11,12

13,14,15 ,19,20,21

16,17,18 , 22,23,24]

if we split it for each 2 chunks.

Answer 1

[Ameer Hamza]

% Example matrix
x(:,:,1) = [1 2 3; 4 5 6];
x(:,:,2) = [1 2 3; 4 5 6]+6;
x(:,:,3) = [1 2 3; 4 5 6]+12;
x(:,:,4) = [1 2 3; 4 5 6]+18;

n = sqrt(size(x,3));
x2 = mat2cell(x, size(x,1), size(x,2), ones(1,size(x,3)));
x2 = reshape(x2,n,n)';
x2 = cell2mat(x2);
x2 =
     1     2     3     7     8     9
     4     5     6    10    11    12
    13    14    15    19    20    21
    16    17    18    22    23    24

Example for another matrix x

% Example matrix
x(:,:,1) = [1 2 3; 4 5 6; 7 8 9];
x(:,:,2) = [1 2 3; 4 5 6; 7 8 9]+9;
x(:,:,3) = [1 2 3; 4 5 6; 7 8 9]+18;
x(:,:,4) = [1 2 3; 4 5 6; 7 8 9]+27;
x(:,:,5) = [1 2 3; 4 5 6; 7 8 9]+36;
x(:,:,6) = [1 2 3; 4 5 6; 7 8 9]+45;
x(:,:,7) = [1 2 3; 4 5 6; 7 8 9]+54;
x(:,:,8) = [1 2 3; 4 5 6; 7 8 9]+63;
x(:,:,9) = [1 2 3; 4 5 6; 7 8 9]+72;

n = sqrt(size(x,3));
x2 = mat2cell(x, size(x,1), size(x,2), ones(1,size(x,3)));
x2 = reshape(x2,n,n)';
x2 = cell2mat(x2);
x2 =
     1     2     3    10    11    12    19    20    21
     4     5     6    13    14    15    22    23    24
     7     8     9    16    17    18    25    26    27
    28    29    30    37    38    39    46    47    48
    31    32    33    40    41    42    49    50    51
    34    35    36    43    44    45    52    53    54
    55    56    57    64    65    66    73    74    75
    58    59    60    67    68    69    76    77    78
    61    62    63    70    71    72    79    80    81

[konstantina vatavali]

thank you very much for your reply!

this gives me error that the number of elements in reshape must not change

[Ameer Hamza]

What is the size of matrix 'x'? Please paste the output of

size(x)

[konstantina vatavali]

size x is 9x9x625

size x2 must be 225*225

[konstantina vatavali]

ok I found it

It works now thank you!

[Ameer Hamza]

I created random matrix of this size and the code work fine for me. Can you make sure that you correctly copied the code?

[konstantina vatavali]

yes it works i made a mistake thank you!

[Ameer Hamza]

Glad to be of help.