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// CXSparse/Source/cs_lsolve: x=L\b, forward solve where x and b are dense
// CXSparse, Copyright (c) 2006-2022, Timothy A. Davis. All Rights Reserved.
// SPDX-License-Identifier: LGPL-2.1+
#include "cs.h"
/* solve Lx=b where x and b are dense. x=b on input, solution on output. */
CS_INT cs_lsolve (const cs *L, CS_ENTRY *x)
{
CS_INT p, j, n, *Lp, *Li ;
CS_ENTRY *Lx ;
if (!CS_CSC (L) || !x) return (0) ; /* check inputs */
n = L->n ; Lp = L->p ; Li = L->i ; Lx = L->x ;
for (j = 0 ; j < n ; j++)
{
x [j] /= Lx [Lp [j]] ;
for (p = Lp [j]+1 ; p < Lp [j+1] ; p++)
{
x [Li [p]] -= Lx [p] * x [j] ;
}
}
return (1) ;
}
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