# Help to make code into a for loop

2 views (last 30 days)
monkey_matlab on 4 Feb 2016
Edited: Geoff Hayes on 4 Feb 2016
Hello,
I would like to know how to go about making the following code into a for loop:
A1 = [0 1 0; 0 0 0; 0 0 1]
%fprintf('%f\n', A1);
rankA1 = rank(A1);
fprintf('Rank of A1 is %5.0d\n', rankA1);
[r,c] = size(A1);
nullityA1 = c - rankA1;
fprintf('Nullity of A1 is %5.0d\n', nullityA1);
A2 = [4 1 -1; 3 2 0; 1 1 0]
rankA2 = rank(A2);
fprintf('Rank of A2 is %5.0d\n', rankA2);
[r,c] = size(A2);
nullityA2 = c - rankA2;
fprintf('Nullity of A1 is %5.1d\n', nullityA2);
A3 = [1 2 3 4; 0 -1 -1 2; 0 0 0 1]
rankA3 = rank(A3);
fprintf('Rank of A3 is %5.0d\n', rankA3);
[r,c] = size(A3);
nullityA3 = c - rankA3;
fprintf('Nullity of A3 is %5.0d\n', nullityA3);
The code after the matrices A1, A2 and A3 is basically the same except for the variables. Thanks for your help.

Geoff Hayes on 4 Feb 2016
Edited: Geoff Hayes on 4 Feb 2016
monkey_matlab - try creating a cell array of the three matrices A1, A2 and A3. (A cell array is used since these three matrices are of different dimensions.)
matrixData = cell(3,1);
matrixData{1} = A1;
matrixData{2} = A2;
matrixData{3} = A3;
for k=1:length(matrixData)
mtxRank = rank(matrixData{k});
fprintf('Rank of A%d is %d\n', k, mtxRank);
[r,c] = size(matrixData{k});
mtxNulity = c - mtxRank;
fprintf('Nullity of A%d is %d\n', k, mtxNulity);
end
In the above, we iterate over each element in the cell array and consider the rank and nullity for each.

### Categories

Find more on Systems of Nonlinear Equations 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!