how to get this code to work for non square matrix
2 views (last 30 days)
Show older comments
Can some1 pls help me modify this code and give me tips on how to get other codes of this nature to run for non square Matrix Function [L, U, P, Q] = gecp(A)
%GECP calculate Gauss elimination with complete pivoting
%
% (G)aussian (E)limination (C)omplete (P)ivoting
% Input : A nxn matrix
% Output
% L = Lower triangular matrix with ones as diagonals
% U = Upper triangular matrix
% P and Q permutations matrices so that P*A*Q = L*U
%
% See also LU
%
% written by : Cheilakos Nick
[n, n] = size(A);
p = 1:n;
q = 1:n;
for k = 1:n-1
[maxc, rowindices] = max( abs(A(k:n, k:n)) );
[maxm, colindex] = max(maxc);
row = rowindices(colindex)+k-1; col = colindex+k-1;
A( [k, row], : ) = A( [row, k], : );
A( :, [k, col] ) = A( :, [col, k] );
p( [k, row] ) = p( [row, k] ); q( [k, col] ) = q( [col, k] );
if A(k,k) == 0
break
end
A(k+1:n,k) = A(k+1:n,k)/A(k,k);
i = k+1:n;
A(i,i) = A(i,i) - A(i,k) * A(k,i);
end
L = tril(A,-1) + eye(n);
U = triu(A);
P = eye(n);
P = P(p,:);
Q = eye(n);
Q = Q(:,q);
0 Comments
Answers (2)
Star Strider
on 28 May 2014
The rref function does a Gauss-Jordan elimination on non-square matrices. (If you ask it nicely, it will even do a matrix inverse for you.)
0 Comments
See Also
Categories
Find more on Operating on Diagonal Matrices 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!