How to repeat a row by a certain factor

I have this sample matrix:

A=[2 2 2; 3 3 3; 4 4 4];

I would like to multiply each row by a certain factor (in this specific case, the first by 2, the second by 1, and the third by 3) to generate:

A_New= 2 2 2 2 2 2 3 3 3 4 4 4 4 4 4 4 4 4

Does anyone have suggestions on how to do this? I tried:

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

but this created separate matrices.

Answer 1

[Mohammad Abouali]

% Creating sample data
A=[2 2 2; 3 3 3; 4 4 4];
nRep=[2,1,3];

% Constructing A_New as instructed.
A_new=cell2mat(arrayfun(@(r) repmat(A(r,:),1,nRep(r)), ...
                        1:numel(nRep), ...
                        'UniformOutput',false));

% printing the results
fprintf('A=');
fprintf('%d ',A_new)
fprintf('\n');

Once you run it you get this:

A=2 2 2 2 2 2 3 3 3 4 4 4 4 4 4 4 4 4

[Mohammad Abouali]

To preserve the structure then do this:

A=[2 2 2; 3 3 3; 4 4 4];

nRep=[2,1,3];

A_new=cell2mat( arrayfun(@(r) repmat(A(r,:),nRep(r),1),(1:numel(nRep))','UniformOutput',false) )

A_new =

       2     2     2
       2     2     2
       3     3     3
       4     4     4
       4     4     4
       4     4     4

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Answer 2

[Jessica]

This is very helpful. Is there a way to preserve the structure so that it is in the format:

A_New=[2 2 2; 2 2 2; 3 3 3; 4 4 4; 4 4 4; 4 4 4];

Thanks!