How to reshape rows into columns

How can I change the following matrix:

[1, 5,0,0; 2,4,0,0; 3, 2,6,4]

to look like:

[1,5; 2, 4; 3,2; 3,6; 3,4]?

Any suggestion would be great. Thanks

Answer 1

[Andrei Bobrov]

A =[1, 5,0,0; 2,4,0,0; 3, 2,6,4]
[i1 j1] = find(A(:,2:end))
sz = size(A)
out = sortrows([A(i1,1) A(sz(1)+sub2ind(sz- [0 1],i1,j1))],1)

more

[i2 j2 c] = find(A)
t = j2~=1
out = sortrows([A(i2(t),1)  c(t)],1)

variant 3

AA = A(:,2:end) 
[i1,~] = find(AA) 
out = sortrows([A(i1,1) reshape(AA(AA~=0),[],1)],1)

[Amandeep]

Thanks for your quick response.

But waht if instead:

A = [1,5,0,0;3,4,0,0;5,2,6,4]

[Andrei Bobrov]

>> A = [1,5,0,0;3,4,0,0;5,2,6,4];

[i2 j2 c] = find(A);

t = j2~=1;

out = [A(i2(t),1) c(t)]

out =

1 5

3 4

5 2

5 6

5 4

[Amandeep]

I think I nearly figured it out

A = [1,5,0,0;3,4,0,0;5,2,6,4]

AA = permute(A(:,2:end),[2,1])

AA = reshape(AA,numel(A(:,2:end)),1)

zero = (AA==0)

AA(zero) = []

Now just trying to create the first column

Answer 2

[Sivakumaran Chandrasekaran]

Hi, There is a command named reshape. Check with it.

Regards, Sivakumaran [e-mail]

[Amandeep]

How do I use reshape on the third row?

[Oleg Komarov]

@Siva: if I were you I wouldn't leave my mail on a forum.