How to shift a matrix

Say I have a matrix that is 3x3:

1 2 3

4 5 6

7 8 9

I want to shift the top and bottom rows:

1 2 3

4 5 6

7 8 9

This would expand it into a 3x4 matrix yes but i mostly want to know how specifically to do this shifting. I was told the imwarp function could help but im not sure. I'm thinking I would have to define a matrix for the first one to shift to? Or something like that?

[the cyclist]

Do you mean a numeric array, or a cell array?

If a numeric array, what do you want in the "empty" spaces (which cannot be empty in a numeric array). Zero? NaN?

[Aldo Hernandez]

Cell array.

[Adam]

They way you have drawn your shifting suggests more than a 3x4 output as your shifted numbers fall in the gaps between the row below/above, which would require a larger matrix to include. Or are the 1, 5 and 7 supposed to all line up in the 2nd column?

[Aldo Hernandez]

Yes that is my bad. 1,5,7 are in same column as are 2,6,8. I'll edit that correction when I get the chancr.

Answer 1

[prasanth s]

loop version:

M=[ 1,2,3;
    4,5,6;
    7,8,9; ];

C=nan(3,4);
for i=1:size(M,1)
    if mod(i,2)==1
        C(i,2:end)=M(i,:);
    else
        C(i,1:end-1)=M(i,:);
    end
end

vector slicing version:

M=[ 1,2,3;
    4,5,6;
    7,8,9; ];

L=mod([1:3]',2)>0;%logical 1 and 0 vector
A=M(L,:);
B=M(not(L),:);
C=nan(3,4);
C(L,2:4)=A;
C(not(L),1:3)=B;

M is input array

C is output array

empty elements is in 'NaN' type. you can get nan value index using 'isnan' function