How to repeat a row by a certain factor
1 view (last 30 days)
Show older comments
Jessica
on 26 Apr 2015
Commented: Mohammad Abouali
on 26 Apr 2015
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.
0 Comments
Accepted Answer
Mohammad Abouali
on 26 Apr 2015
Edited: Mohammad Abouali
on 26 Apr 2015
% 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
1 Comment
Mohammad Abouali
on 26 Apr 2015
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
If this is answering your question, please accept the answer by choosing the green button on top
More Answers (1)
See Also
Categories
Find more on Structures in Help Center and File Exchange
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!