function [L,p,q] = lchol (A)						    %#ok
%LCHOL sparse A=L*L' factorization.
%   Note that L*L' (LCHOL) and L*D*L' (LDLCHOL) factorizations are faster than
%   R'*R (CHOL2 and CHOL) and use less memory.  The LL' and LDL' factorization
%   methods use tril(A).  A must be sparse.
%
%   Example:
%   L = lchol (A)                 same as L = chol (A')', just faster
%   [L,p] = lchol (A)             save as [R,p] = chol(A') ; L=R', just faster
%   [L,p,q] = lchol (A)           factorizes A(q,q) into L*L', where q is a
%                                 fill-reducing ordering
%
%   See also CHOL2, LDLCHOL, CHOL.

%   Copyright 2006, Timothy A. Davis
%   http://www.cise.ufl.edu/research/sparse

error ('lchol mexFunction not found') ;