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function [L,U,P] = lu_rightp (A)
%LU_RIGHTP right-looking LU factorization, with partial pivoting.
%
% Example:
% [L,U,P] = lu_rightp (A)
% See also: cs_demo
% Copyright 2006-2007, Timothy A. Davis.
% http://www.cise.ufl.edu/research/sparse
n = size (A,1) ;
P = eye (n) ;
for k = 1:n
[x,i] = max (abs (A (k:n,k))) ; % partial pivoting
i = i+k-1 ;
P ([k i],:) = P ([i k], :) ;
A ([k i],:) = A ([i k], :) ; % (6.10), (6.11)
A (k+1:n,k) = A (k+1:n,k) / A (k,k) ; % (6.12)
A (k+1:n,k+1:n) = A (k+1:n,k+1:n) - A (k+1:n,k) * A (k,k+1:n) ; % (6.9)
end
L = tril (A,-1) + eye (n) ;
U = triu (A) ;
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