# How to reshape matrix 2 columns by 2 columns

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Ren Li on 30 Jul 2020
Answered: Bruno Luong on 2 Aug 2020
for example, an array like this:
1 0 2 0 2 3
5 4 4 0 1 4
4 2 2 4 2 2
1 1 0 4 3 1
How to reshape it into an array like this:
1 0
5 4
4 2
1 1
2 0
4 0
2 4
0 4
2 3
1 4
2 2
3 1

Sriram Tadavarty on 30 Jul 2020
Hi Ren,
Use individual columns and append them. For the sample code you provided, it can be done as below:
a = [1 0 2 0 2 3;
5 4 4 0 1 4;
4 2 2 4 2 2;
1 1 0 4 3 1];
a1 = a(:,1:2:end); % Select the odd numbered columns
a2 = a(:,2:2:end); % Select the even numbered columns
[a1(:) a2(:)] % Append them
Hope this helps.
Regards,
Sriram

Show 1 older comment
madhan ravi on 30 Jul 2020
Sriram how’s this different from my answer?
Sriram Tadavarty on 30 Jul 2020
If i knew that this is already answered, i wouldn't have answered it at all. I think we both looked at the same time, but my answer publish went late by couple of mins.
Sorry for any trouble here. I didn't do anything intentional. I am even ok, if you wanted yours to be an accepted answer, as you mentioned early enough. My answer has just some additional comments.
Thanking you.
Regards,
Sriram
madhan ravi on 30 Jul 2020
No problem Sriram ;). By the way I think concatenate could be used instead of append I believe. Append is something which is used for adding something at the end of already existing variable/array.

Walter Roberson on 30 Jul 2020
cell2mat(mat2cell(YourArray, size(YourArray,1), 2*ones(1,size(YourArray,2)/2)).')

#### 1 Comment

Ren Li on 2 Aug 2020
Thank you very much for the code, after spending sometime understanding it, I believe this gives even more flexibility on how to rearrange the matrix, now with this code, I can easily reshape it N columns by N columns, which in my case is exactly what I will need to do next. So again thank you so much

madhan ravi on 30 Jul 2020
First = matrix(:, 1:2:end);
Second = matrix(:, 2:2:end);
Wanted = [First(:), Second(:)]

#### 1 Comment

Ren Li on 30 Jul 2020
thank you very much

Bruno Luong on 2 Aug 2020
You want a reshape? Here is reshape method:
B = reshape(permute(reshape(A,size(A,1),2,[]),[1 3 2]),[],2)

R2018a

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