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function [vnz,rnz,parent,c,leftmost,p,q] = cs_sqr (A) %#ok
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%CS_SQR symbolic sparse QR factorization.
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% [vnz,rnz,parent,c,leftmost,p] = cs_sqr(A): symbolic QR of A(p,:).
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% [vnz,rnz,parent,c,leftmost,p,q] = cs_sqr(A) computes the symbolic QR
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% factorization of A(p,q). The fill-reducing ordering q is found via
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% vnz is the number of entries in the matrix of Householder vectors, V.
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% rnz is the number of entries in R. parent is elimination tree.
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% c(i) is the number of entries in R(i,:). leftmost(i) = min(find(A(i,q))).
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% p is the row permutation used to ensure R has a symbolically zero-free
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% diagonal (it can be larger than m if A is structurally rank deficient).
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% q is the fill-reducing ordering, if requested.
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% Prob = UFget ('HB/ibm32') ; A = Prob.A ;
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% [vnz, rnz, parent, c, leftmost, p, q] = cs_sqr (A) ;
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% See also CS_AMD, CS_QR.
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% Copyright 2006-2007, Timothy A. Davis.
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% http://www.cise.ufl.edu/research/sparse
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error ('cs_sqr mexFunction not found') ;