MATLAB: Convert the mxn size Matrix to square Matrix without using loop or if

square matrix

Hi,
I have a random mxn matrix, like 4×6 and I want it to be square. For example, a original 4×6 matrix would be created by deleting the first and second column to a formed a 4×4 matrix.
A =
      0.8147    0.6324    0.9575    0.9572    0.4218    0.6557
      0.9058    0.0975    0.9649    0.4854    0.9157    0.0357
      0.1270    0.2785    0.1576    0.8003    0.7922    0.8491
      0.9134    0.5469    0.9706    0.1419    0.9595    0.9340
B = 
   0.9575    0.9572    0.4218    0.6557
   0.9649    0.4854    0.9157    0.0357
   0.1576    0.8003    0.7922    0.8491
   0.9706    0.1419    0.9595    0.9340
How can I create from A to B without using loop or if-statment? and it should be work for all mxn, which m and n could be any number.
I started like this but got stunned. [m n] = size(A);
newA(m,:) = [];
newA(:,n) = [];
Thanks

Best Answer

David - if you want to convert your (say) 4x6 matrix into a 4x4 by removing the first two columns, then you could do something like
 B = A(:,3:end);
In the above, we use the colon to mean "all rows", and the 3:end to mean "get columns 3 through to the end". You can extend this to other (different sized) matrices.
EDIT
In your code where you try to set the mth row to the empty matrix, and the nth column to the empty matrix
 newA(m,:) = [];
 newA(:,n) = [];
what you really want to do is to set the first two columns to be the empty matrix which has the effect of removing them. Try
 newA = A;
 newA(:,1:2) = [];
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