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/*! @file dgsitf.c
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 * \brief Computes an ILU factorization of a general sparse matrix
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 *
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 * 
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 * -- SuperLU routine (version 4.0) --
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 * Lawrence Berkeley National Laboratory.
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 * June 30, 2009
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 * 
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 */
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#include "slu_ddefs.h"
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#ifdef DEBUG
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int num_drop_L;
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#endif
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/*! \brief
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 *
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 * 
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 * Purpose
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 * =======
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 *
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 * DGSITRF computes an ILU factorization of a general sparse m-by-n
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 * matrix A using partial pivoting with row interchanges.
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 * The factorization has the form
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 *     Pr * A = L * U
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 * where Pr is a row permutation matrix, L is lower triangular with unit
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 * diagonal elements (lower trapezoidal if A->nrow > A->ncol), and U is upper
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 * triangular (upper trapezoidal if A->nrow < A->ncol).
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 *
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 * See supermatrix.h for the definition of 'SuperMatrix' structure.
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 *
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 * Arguments
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 * =========
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 *
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 * options (input) superlu_options_t*
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 *	   The structure defines the input parameters to control
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 *	   how the ILU decomposition will be performed.
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 *
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 * A	    (input) SuperMatrix*
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 *	    Original matrix A, permuted by columns, of dimension
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 *	    (A->nrow, A->ncol). The type of A can be:
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 *	    Stype = SLU_NCP; Dtype = SLU_D; Mtype = SLU_GE.
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 *
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 * relax    (input) int
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 *	    To control degree of relaxing supernodes. If the number
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 *	    of nodes (columns) in a subtree of the elimination tree is less
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 *	    than relax, this subtree is considered as one supernode,
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 *	    regardless of the row structures of those columns.
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 *
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 * panel_size (input) int
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 *	    A panel consists of at most panel_size consecutive columns.
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 *
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 * etree    (input) int*, dimension (A->ncol)
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 *	    Elimination tree of A'*A.
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 *	    Note: etree is a vector of parent pointers for a forest whose
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 *	    vertices are the integers 0 to A->ncol-1; etree[root]==A->ncol.
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 *	    On input, the columns of A should be permuted so that the
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 *	    etree is in a certain postorder.
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 *
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 * work     (input/output) void*, size (lwork) (in bytes)
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 *	    User-supplied work space and space for the output data structures.
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 *	    Not referenced if lwork = 0;
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 *
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 * lwork   (input) int
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 *	   Specifies the size of work array in bytes.
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 *	   = 0:  allocate space internally by system malloc;
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 *	   > 0:  use user-supplied work array of length lwork in bytes,
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 *		 returns error if space runs out.
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 *	   = -1: the routine guesses the amount of space needed without
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 *		 performing the factorization, and returns it in
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 *		 *info; no other side effects.
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 *
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 * perm_c   (input) int*, dimension (A->ncol)
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 *	    Column permutation vector, which defines the
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 *	    permutation matrix Pc; perm_c[i] = j means column i of A is
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 *	    in position j in A*Pc.
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 *	    When searching for diagonal, perm_c[*] is applied to the
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 *	    row subscripts of A, so that diagonal threshold pivoting
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 *	    can find the diagonal of A, rather than that of A*Pc.
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 *
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 * perm_r   (input/output) int*, dimension (A->nrow)
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 *	    Row permutation vector which defines the permutation matrix Pr,
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 *	    perm_r[i] = j means row i of A is in position j in Pr*A.
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 *	    If options->Fact = SamePattern_SameRowPerm, the pivoting routine
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 *	       will try to use the input perm_r, unless a certain threshold
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 *	       criterion is violated. In that case, perm_r is overwritten by
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 *	       a new permutation determined by partial pivoting or diagonal
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 *	       threshold pivoting.
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 *	    Otherwise, perm_r is output argument;
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 *
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 * L	    (output) SuperMatrix*
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 *	    The factor L from the factorization Pr*A=L*U; use compressed row
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 *	    subscripts storage for supernodes, i.e., L has type:
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 *	    Stype = SLU_SC, Dtype = SLU_D, Mtype = SLU_TRLU.
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 *
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 * U	    (output) SuperMatrix*
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 *	    The factor U from the factorization Pr*A*Pc=L*U. Use column-wise
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 *	    storage scheme, i.e., U has types: Stype = SLU_NC,
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 *	    Dtype = SLU_D, Mtype = SLU_TRU.
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 *
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 * stat     (output) SuperLUStat_t*
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 *	    Record the statistics on runtime and floating-point operation count.
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 *	    See slu_util.h for the definition of 'SuperLUStat_t'.
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 *
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 * info     (output) int*
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 *	    = 0: successful exit
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 *	    < 0: if info = -i, the i-th argument had an illegal value
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 *	    > 0: if info = i, and i is
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 *	       <= A->ncol: number of zero pivots. They are replaced by small
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 *		  entries according to options->ILU_FillTol.
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 *	       > A->ncol: number of bytes allocated when memory allocation
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 *		  failure occurred, plus A->ncol. If lwork = -1, it is
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 *		  the estimated amount of space needed, plus A->ncol.
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 *
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 * ======================================================================
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 *
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 * Local Working Arrays:
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 * ======================
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 *   m = number of rows in the matrix
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 *   n = number of columns in the matrix
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 *
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 *   marker[0:3*m-1]: marker[i] = j means that node i has been
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 *	reached when working on column j.
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 *	Storage: relative to original row subscripts
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 *	NOTE: There are 4 of them:
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 *	      marker/marker1 are used for panel dfs, see (ilu_)dpanel_dfs.c;
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 *	      marker2 is used for inner-factorization, see (ilu)_dcolumn_dfs.c;
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 *	      marker_relax(has its own space) is used for relaxed supernodes.
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 *
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 *   parent[0:m-1]: parent vector used during dfs
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 *	Storage: relative to new row subscripts
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 *
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 *   xplore[0:m-1]: xplore[i] gives the location of the next (dfs)
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 *	unexplored neighbor of i in lsub[*]
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 *
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 *   segrep[0:nseg-1]: contains the list of supernodal representatives
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 *	in topological order of the dfs. A supernode representative is the
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 *	last column of a supernode.
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 *	The maximum size of segrep[] is n.
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 *
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 *   repfnz[0:W*m-1]: for a nonzero segment U[*,j] that ends at a
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 *	supernodal representative r, repfnz[r] is the location of the first
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 *	nonzero in this segment.  It is also used during the dfs: repfnz[r]>0
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 *	indicates the supernode r has been explored.
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 *	NOTE: There are W of them, each used for one column of a panel.
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 *
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 *   panel_lsub[0:W*m-1]: temporary for the nonzeros row indices below
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 *	the panel diagonal. These are filled in during dpanel_dfs(), and are
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 *	used later in the inner LU factorization within the panel.
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 *	panel_lsub[]/dense[] pair forms the SPA data structure.
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 *	NOTE: There are W of them.
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 *
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 *   dense[0:W*m-1]: sparse accumulating (SPA) vector for intermediate values;
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 *		   NOTE: there are W of them.
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 *
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 *   tempv[0:*]: real temporary used for dense numeric kernels;
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 *	The size of this array is defined by NUM_TEMPV() in slu_util.h.
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 *	It is also used by the dropping routine ilu_ddrop_row().
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 * 
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 */
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void
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dgsitrf(superlu_options_t *options, SuperMatrix *A, int relax, int panel_size,
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	int *etree, void *work, int lwork, int *perm_c, int *perm_r,
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	SuperMatrix *L, SuperMatrix *U, SuperLUStat_t *stat, int *info)
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{
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    /* Local working arrays */
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    NCPformat *Astore;
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    int       *iperm_r = NULL; /* inverse of perm_r; used when
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				  options->Fact == SamePattern_SameRowPerm */
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    int       *iperm_c; /* inverse of perm_c */
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    int       *swap, *iswap; /* swap is used to store the row permutation
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				during the factorization. Initially, it is set
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				to iperm_c (row indeces of Pc*A*Pc').
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				iswap is the inverse of swap. After the
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				factorization, it is equal to perm_r. */
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    int       *iwork;
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    double   *dwork;
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    int       *segrep, *repfnz, *parent, *xplore;
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    int       *panel_lsub; /* dense[]/panel_lsub[] pair forms a w-wide SPA */
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    int       *marker, *marker_relax;
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    double    *dense, *tempv;
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    int       *relax_end, *relax_fsupc;
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    double    *a;
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    int       *asub;
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    int       *xa_begin, *xa_end;
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    int       *xsup, *supno;
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    int       *xlsub, *xlusup, *xusub;
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    int       nzlumax;
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    double    *amax; 
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    double    drop_sum;
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    static GlobalLU_t Glu; /* persistent to facilitate multiple factors. */
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    int       *iwork2;	   /* used by the second dropping rule */
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    /* Local scalars */
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    fact_t    fact = options->Fact;
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    double    diag_pivot_thresh = options->DiagPivotThresh;
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    double    drop_tol = options->ILU_DropTol; /* tau */
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    double    fill_ini = options->ILU_FillTol; /* tau^hat */
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    double    gamma = options->ILU_FillFactor;
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    int       drop_rule = options->ILU_DropRule;
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    milu_t    milu = options->ILU_MILU;
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    double    fill_tol;
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    int       pivrow;	/* pivotal row number in the original matrix A */
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    int       nseg1;	/* no of segments in U-column above panel row jcol */
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    int       nseg;	/* no of segments in each U-column */
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    register int jcol;
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    register int kcol;	/* end column of a relaxed snode */
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    register int icol;
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    register int i, k, jj, new_next, iinfo;
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    int       m, n, min_mn, jsupno, fsupc, nextlu, nextu;
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    int       w_def;	/* upper bound on panel width */
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    int       usepr, iperm_r_allocated = 0;
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    int       nnzL, nnzU;
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    int       *panel_histo = stat->panel_histo;
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    flops_t   *ops = stat->ops;
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    int       last_drop;/* the last column which the dropping rules applied */
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    int       quota;
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    int       nnzAj;	/* number of nonzeros in A(:,1:j) */
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    int       nnzLj, nnzUj;
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    double    tol_L = drop_tol, tol_U = drop_tol;
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    double zero = 0.0;
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    /* Executable */	   
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    iinfo    = 0;
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    m	     = A->nrow;
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    n	     = A->ncol;
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    min_mn   = SUPERLU_MIN(m, n);
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    Astore   = A->Store;
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    a	     = Astore->nzval;
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    asub     = Astore->rowind;
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    xa_begin = Astore->colbeg;
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    xa_end   = Astore->colend;
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    /* Allocate storage common to the factor routines */
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    *info = dLUMemInit(fact, work, lwork, m, n, Astore->nnz, panel_size,
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		       gamma, L, U, &Glu, &iwork, &dwork);
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    if ( *info ) return;
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    xsup    = Glu.xsup;
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    supno   = Glu.supno;
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    xlsub   = Glu.xlsub;
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    xlusup  = Glu.xlusup;
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    xusub   = Glu.xusub;
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    SetIWork(m, n, panel_size, iwork, &segrep, &parent, &xplore,
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	     &repfnz, &panel_lsub, &marker_relax, &marker);
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    dSetRWork(m, panel_size, dwork, &dense, &tempv);
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    usepr = (fact == SamePattern_SameRowPerm);
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    if ( usepr ) {
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	/* Compute the inverse of perm_r */
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	iperm_r = (int *) intMalloc(m);
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	for (k = 0; k < m; ++k) iperm_r[perm_r[k]] = k;
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	iperm_r_allocated = 1;
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    }
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    iperm_c = (int *) intMalloc(n);
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    for (k = 0; k < n; ++k) iperm_c[perm_c[k]] = k;
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    swap = (int *)intMalloc(n);
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    for (k = 0; k < n; k++) swap[k] = iperm_c[k];
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    iswap = (int *)intMalloc(n);
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    for (k = 0; k < n; k++) iswap[k] = perm_c[k];
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    amax = (double *) doubleMalloc(panel_size);
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    if (drop_rule & DROP_SECONDARY)
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	iwork2 = (int *)intMalloc(n);
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    else
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	iwork2 = NULL;
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    nnzAj = 0;
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    nnzLj = 0;
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    nnzUj = 0;
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    last_drop = SUPERLU_MAX(min_mn - 2 * sp_ienv(7), (int)(min_mn * 0.95));
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    /* Identify relaxed snodes */
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    relax_end = (int *) intMalloc(n);
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    relax_fsupc = (int *) intMalloc(n);
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    if ( options->SymmetricMode == YES )
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	ilu_heap_relax_snode(n, etree, relax, marker, relax_end, relax_fsupc);
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    else
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	ilu_relax_snode(n, etree, relax, marker, relax_end, relax_fsupc);
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    ifill (perm_r, m, EMPTY);
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    ifill (marker, m * NO_MARKER, EMPTY);
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    supno[0] = -1;
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    xsup[0]  = xlsub[0] = xusub[0] = xlusup[0] = 0;
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    w_def    = panel_size;
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    /* Mark the rows used by relaxed supernodes */
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    ifill (marker_relax, m, EMPTY);
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    i = mark_relax(m, relax_end, relax_fsupc, xa_begin, xa_end,
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	         asub, marker_relax);
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#if ( PRNTlevel >= 1)
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    printf("%d relaxed supernodes.\n", i);
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#endif
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    /*
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     * Work on one "panel" at a time. A panel is one of the following:
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     *	   (a) a relaxed supernode at the bottom of the etree, or
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     *	   (b) panel_size contiguous columns, defined by the user
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     */
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    for (jcol = 0; jcol < min_mn; ) {
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	if ( relax_end[jcol] != EMPTY ) { /* start of a relaxed snode */
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	    kcol = relax_end[jcol];	  /* end of the relaxed snode */
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	    panel_histo[kcol-jcol+1]++;
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	    /* Drop small rows in the previous supernode. */
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	    if (jcol > 0 && jcol < last_drop) {
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		int first = xsup[supno[jcol - 1]];
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		int last = jcol - 1;
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		int quota;
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		/* Compute the quota */
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		if (drop_rule & DROP_PROWS)
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		    quota = gamma * Astore->nnz / m * (m - first) / m
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			    * (last - first + 1);
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		else if (drop_rule & DROP_COLUMN) {
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		    int i;
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		    quota = 0;
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		    for (i = first; i <= last; i++)
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			quota += xa_end[i] - xa_begin[i];
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		    quota = gamma * quota * (m - first) / m;
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		} else if (drop_rule & DROP_AREA)
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		    quota = gamma * nnzAj * (1.0 - 0.5 * (last + 1.0) / m)
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			    - nnzLj;
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		else
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		    quota = m * n;
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		fill_tol = pow(fill_ini, 1.0 - 0.5 * (first + last) / min_mn);
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		/* Drop small rows */
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		i = ilu_ddrop_row(options, first, last, tol_L, quota, &nnzLj,
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				  &fill_tol, &Glu, tempv, iwork2, 0);
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		/* Reset the parameters */
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		if (drop_rule & DROP_DYNAMIC) {
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		    if (gamma * nnzAj * (1.0 - 0.5 * (last + 1.0) / m)
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			     < nnzLj)
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			tol_L = SUPERLU_MIN(1.0, tol_L * 2.0);
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		    else
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			tol_L = SUPERLU_MAX(drop_tol, tol_L * 0.5);
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		}
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		if (fill_tol < 0) iinfo -= (int)fill_tol;
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#ifdef DEBUG
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		num_drop_L += i * (last - first + 1);
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#endif
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	    }
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	    /* --------------------------------------
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	     * Factorize the relaxed supernode(jcol:kcol)
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	     * -------------------------------------- */
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	    /* Determine the union of the row structure of the snode */
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	    if ( (*info = ilu_dsnode_dfs(jcol, kcol, asub, xa_begin, xa_end,
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					 marker, &Glu)) != 0 )
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		return;
kusano 7d535a
kusano 7d535a
	    nextu    = xusub[jcol];
kusano 7d535a
	    nextlu   = xlusup[jcol];
kusano 7d535a
	    jsupno   = supno[jcol];
kusano 7d535a
	    fsupc    = xsup[jsupno];
kusano 7d535a
	    new_next = nextlu + (xlsub[fsupc+1]-xlsub[fsupc])*(kcol-jcol+1);
kusano 7d535a
	    nzlumax = Glu.nzlumax;
kusano 7d535a
	    while ( new_next > nzlumax ) {
kusano 7d535a
		if ((*info = dLUMemXpand(jcol, nextlu, LUSUP, &nzlumax, &Glu)))
kusano 7d535a
		    return;
kusano 7d535a
	    }
kusano 7d535a
kusano 7d535a
	    for (icol = jcol; icol <= kcol; icol++) {
kusano 7d535a
		xusub[icol+1] = nextu;
kusano 7d535a
kusano 7d535a
		amax[0] = 0.0;
kusano 7d535a
		/* Scatter into SPA dense[*] */
kusano 7d535a
		for (k = xa_begin[icol]; k < xa_end[icol]; k++) {
kusano 7d535a
		    register double tmp = fabs(a[k]);
kusano 7d535a
		    if (tmp > amax[0]) amax[0] = tmp;
kusano 7d535a
		    dense[asub[k]] = a[k];
kusano 7d535a
		}
kusano 7d535a
		nnzAj += xa_end[icol] - xa_begin[icol];
kusano 7d535a
		if (amax[0] == 0.0) {
kusano 7d535a
		    amax[0] = fill_ini;
kusano 7d535a
#if ( PRNTlevel >= 1)
kusano 7d535a
		    printf("Column %d is entirely zero!\n", icol);
kusano 7d535a
		    fflush(stdout);
kusano 7d535a
#endif
kusano 7d535a
		}
kusano 7d535a
kusano 7d535a
		/* Numeric update within the snode */
kusano 7d535a
		dsnode_bmod(icol, jsupno, fsupc, dense, tempv, &Glu, stat);
kusano 7d535a
kusano 7d535a
		if (usepr) pivrow = iperm_r[icol];
kusano 7d535a
		fill_tol = pow(fill_ini, 1.0 - (double)icol / (double)min_mn);
kusano 7d535a
		if ( (*info = ilu_dpivotL(icol, diag_pivot_thresh, &usepr,
kusano 7d535a
					  perm_r, iperm_c[icol], swap, iswap,
kusano 7d535a
					  marker_relax, &pivrow,
kusano 7d535a
                                          amax[0] * fill_tol, milu, zero,
kusano 7d535a
                                          &Glu, stat)) ) {
kusano 7d535a
		    iinfo++;
kusano 7d535a
		    marker[pivrow] = kcol;
kusano 7d535a
		}
kusano 7d535a
kusano 7d535a
	    }
kusano 7d535a
kusano 7d535a
	    jcol = kcol + 1;
kusano 7d535a
kusano 7d535a
	} else { /* Work on one panel of panel_size columns */
kusano 7d535a
kusano 7d535a
	    /* Adjust panel_size so that a panel won't overlap with the next
kusano 7d535a
	     * relaxed snode.
kusano 7d535a
	     */
kusano 7d535a
	    panel_size = w_def;
kusano 7d535a
	    for (k = jcol + 1; k < SUPERLU_MIN(jcol+panel_size, min_mn); k++)
kusano 7d535a
		if ( relax_end[k] != EMPTY ) {
kusano 7d535a
		    panel_size = k - jcol;
kusano 7d535a
		    break;
kusano 7d535a
		}
kusano 7d535a
	    if ( k == min_mn ) panel_size = min_mn - jcol;
kusano 7d535a
	    panel_histo[panel_size]++;
kusano 7d535a
kusano 7d535a
	    /* symbolic factor on a panel of columns */
kusano 7d535a
	    ilu_dpanel_dfs(m, panel_size, jcol, A, perm_r, &nseg1,
kusano 7d535a
                          dense, amax, panel_lsub, segrep, repfnz,
kusano 7d535a
                          marker, parent, xplore, &Glu);
kusano 7d535a
kusano 7d535a
	    /* numeric sup-panel updates in topological order */
kusano 7d535a
	    dpanel_bmod(m, panel_size, jcol, nseg1, dense,
kusano 7d535a
			tempv, segrep, repfnz, &Glu, stat);
kusano 7d535a
kusano 7d535a
	    /* Sparse LU within the panel, and below panel diagonal */
kusano 7d535a
	    for (jj = jcol; jj < jcol + panel_size; jj++) {
kusano 7d535a
kusano 7d535a
		k = (jj - jcol) * m; /* column index for w-wide arrays */
kusano 7d535a
kusano 7d535a
		nseg = nseg1;	/* Begin after all the panel segments */
kusano 7d535a
kusano 7d535a
		nnzAj += xa_end[jj] - xa_begin[jj];
kusano 7d535a
kusano 7d535a
		if ((*info = ilu_dcolumn_dfs(m, jj, perm_r, &nseg,
kusano 7d535a
					     &panel_lsub[k], segrep, &repfnz[k],
kusano 7d535a
					     marker, parent, xplore, &Glu)))
kusano 7d535a
		    return;
kusano 7d535a
kusano 7d535a
		/* Numeric updates */
kusano 7d535a
		if ((*info = dcolumn_bmod(jj, (nseg - nseg1), &dense[k],
kusano 7d535a
					  tempv, &segrep[nseg1], &repfnz[k],
kusano 7d535a
					  jcol, &Glu, stat)) != 0) return;
kusano 7d535a
kusano 7d535a
		/* Make a fill-in position if the column is entirely zero */
kusano 7d535a
		if (xlsub[jj + 1] == xlsub[jj]) {
kusano 7d535a
		    register int i, row;
kusano 7d535a
		    int nextl;
kusano 7d535a
		    int nzlmax = Glu.nzlmax;
kusano 7d535a
		    int *lsub = Glu.lsub;
kusano 7d535a
		    int *marker2 = marker + 2 * m;
kusano 7d535a
kusano 7d535a
		    /* Allocate memory */
kusano 7d535a
		    nextl = xlsub[jj] + 1;
kusano 7d535a
		    if (nextl >= nzlmax) {
kusano 7d535a
			int error = dLUMemXpand(jj, nextl, LSUB, &nzlmax, &Glu);
kusano 7d535a
			if (error) { *info = error; return; }
kusano 7d535a
			lsub = Glu.lsub;
kusano 7d535a
		    }
kusano 7d535a
		    xlsub[jj + 1]++;
kusano 7d535a
		    assert(xlusup[jj]==xlusup[jj+1]);
kusano 7d535a
		    xlusup[jj + 1]++;
kusano 7d535a
		    Glu.lusup[xlusup[jj]] = zero;
kusano 7d535a
kusano 7d535a
		    /* Choose a row index (pivrow) for fill-in */
kusano 7d535a
		    for (i = jj; i < n; i++)
kusano 7d535a
			if (marker_relax[swap[i]] <= jj) break;
kusano 7d535a
		    row = swap[i];
kusano 7d535a
		    marker2[row] = jj;
kusano 7d535a
		    lsub[xlsub[jj]] = row;
kusano 7d535a
#ifdef DEBUG
kusano 7d535a
		    printf("Fill col %d.\n", jj);
kusano 7d535a
		    fflush(stdout);
kusano 7d535a
#endif
kusano 7d535a
		}
kusano 7d535a
kusano 7d535a
		/* Computer the quota */
kusano 7d535a
		if (drop_rule & DROP_PROWS)
kusano 7d535a
		    quota = gamma * Astore->nnz / m * jj / m;
kusano 7d535a
		else if (drop_rule & DROP_COLUMN)
kusano 7d535a
		    quota = gamma * (xa_end[jj] - xa_begin[jj]) *
kusano 7d535a
			    (jj + 1) / m;
kusano 7d535a
		else if (drop_rule & DROP_AREA)
kusano 7d535a
		    quota = gamma * 0.9 * nnzAj * 0.5 - nnzUj;
kusano 7d535a
		else
kusano 7d535a
		    quota = m;
kusano 7d535a
kusano 7d535a
		/* Copy the U-segments to ucol[*] and drop small entries */
kusano 7d535a
		if ((*info = ilu_dcopy_to_ucol(jj, nseg, segrep, &repfnz[k],
kusano 7d535a
					       perm_r, &dense[k], drop_rule,
kusano 7d535a
					       milu, amax[jj - jcol] * tol_U,
kusano 7d535a
					       quota, &drop_sum, &nnzUj, &Glu,
kusano 7d535a
					       iwork2)) != 0)
kusano 7d535a
		    return;
kusano 7d535a
kusano 7d535a
		/* Reset the dropping threshold if required */
kusano 7d535a
		if (drop_rule & DROP_DYNAMIC) {
kusano 7d535a
		    if (gamma * 0.9 * nnzAj * 0.5 < nnzLj)
kusano 7d535a
			tol_U = SUPERLU_MIN(1.0, tol_U * 2.0);
kusano 7d535a
		    else
kusano 7d535a
			tol_U = SUPERLU_MAX(drop_tol, tol_U * 0.5);
kusano 7d535a
		}
kusano 7d535a
kusano 7d535a
                drop_sum *= MILU_ALPHA;
kusano 7d535a
		if (usepr) pivrow = iperm_r[jj];
kusano 7d535a
		fill_tol = pow(fill_ini, 1.0 - (double)jj / (double)min_mn);
kusano 7d535a
		if ( (*info = ilu_dpivotL(jj, diag_pivot_thresh, &usepr, perm_r,
kusano 7d535a
					  iperm_c[jj], swap, iswap,
kusano 7d535a
					  marker_relax, &pivrow,
kusano 7d535a
					  amax[jj - jcol] * fill_tol, milu,
kusano 7d535a
					  drop_sum, &Glu, stat)) ) {
kusano 7d535a
		    iinfo++;
kusano 7d535a
		    marker[m + pivrow] = jj;
kusano 7d535a
		    marker[2 * m + pivrow] = jj;
kusano 7d535a
		}
kusano 7d535a
kusano 7d535a
		/* Reset repfnz[] for this column */
kusano 7d535a
		resetrep_col (nseg, segrep, &repfnz[k]);
kusano 7d535a
kusano 7d535a
		/* Start a new supernode, drop the previous one */
kusano 7d535a
		if (jj > 0 && supno[jj] > supno[jj - 1] && jj < last_drop) {
kusano 7d535a
		    int first = xsup[supno[jj - 1]];
kusano 7d535a
		    int last = jj - 1;
kusano 7d535a
		    int quota;
kusano 7d535a
kusano 7d535a
		    /* Compute the quota */
kusano 7d535a
		    if (drop_rule & DROP_PROWS)
kusano 7d535a
			quota = gamma * Astore->nnz / m * (m - first) / m
kusano 7d535a
				* (last - first + 1);
kusano 7d535a
		    else if (drop_rule & DROP_COLUMN) {
kusano 7d535a
			int i;
kusano 7d535a
			quota = 0;
kusano 7d535a
			for (i = first; i <= last; i++)
kusano 7d535a
			    quota += xa_end[i] - xa_begin[i];
kusano 7d535a
			quota = gamma * quota * (m - first) / m;
kusano 7d535a
		    } else if (drop_rule & DROP_AREA)
kusano 7d535a
			quota = gamma * nnzAj * (1.0 - 0.5 * (last + 1.0)
kusano 7d535a
				/ m) - nnzLj;
kusano 7d535a
		    else
kusano 7d535a
			quota = m * n;
kusano 7d535a
		    fill_tol = pow(fill_ini, 1.0 - 0.5 * (first + last) /
kusano 7d535a
			    (double)min_mn);
kusano 7d535a
kusano 7d535a
		    /* Drop small rows */
kusano 7d535a
		    i = ilu_ddrop_row(options, first, last, tol_L, quota,
kusano 7d535a
				      &nnzLj, &fill_tol, &Glu, tempv, iwork2,
kusano 7d535a
				      1);
kusano 7d535a
kusano 7d535a
		    /* Reset the parameters */
kusano 7d535a
		    if (drop_rule & DROP_DYNAMIC) {
kusano 7d535a
			if (gamma * nnzAj * (1.0 - 0.5 * (last + 1.0) / m)
kusano 7d535a
				< nnzLj)
kusano 7d535a
			    tol_L = SUPERLU_MIN(1.0, tol_L * 2.0);
kusano 7d535a
			else
kusano 7d535a
			    tol_L = SUPERLU_MAX(drop_tol, tol_L * 0.5);
kusano 7d535a
		    }
kusano 7d535a
		    if (fill_tol < 0) iinfo -= (int)fill_tol;
kusano 7d535a
#ifdef DEBUG
kusano 7d535a
		    num_drop_L += i * (last - first + 1);
kusano 7d535a
#endif
kusano 7d535a
		} /* if start a new supernode */
kusano 7d535a
kusano 7d535a
	    } /* for */
kusano 7d535a
kusano 7d535a
	    jcol += panel_size; /* Move to the next panel */
kusano 7d535a
kusano 7d535a
	} /* else */
kusano 7d535a
kusano 7d535a
    } /* for */
kusano 7d535a
kusano 7d535a
    *info = iinfo;
kusano 7d535a
kusano 7d535a
    if ( m > n ) {
kusano 7d535a
	k = 0;
kusano 7d535a
	for (i = 0; i < m; ++i)
kusano 7d535a
	    if ( perm_r[i] == EMPTY ) {
kusano 7d535a
		perm_r[i] = n + k;
kusano 7d535a
		++k;
kusano 7d535a
	    }
kusano 7d535a
    }
kusano 7d535a
kusano 7d535a
    ilu_countnz(min_mn, &nnzL, &nnzU, &Glu);
kusano 7d535a
    fixupL(min_mn, perm_r, &Glu);
kusano 7d535a
kusano 7d535a
    dLUWorkFree(iwork, dwork, &Glu); /* Free work space and compress storage */
kusano 7d535a
kusano 7d535a
    if ( fact == SamePattern_SameRowPerm ) {
kusano 7d535a
	/* L and U structures may have changed due to possibly different
kusano 7d535a
	   pivoting, even though the storage is available.
kusano 7d535a
	   There could also be memory expansions, so the array locations
kusano 7d535a
	   may have changed, */
kusano 7d535a
	((SCformat *)L->Store)->nnz = nnzL;
kusano 7d535a
	((SCformat *)L->Store)->nsuper = Glu.supno[n];
kusano 7d535a
	((SCformat *)L->Store)->nzval = Glu.lusup;
kusano 7d535a
	((SCformat *)L->Store)->nzval_colptr = Glu.xlusup;
kusano 7d535a
	((SCformat *)L->Store)->rowind = Glu.lsub;
kusano 7d535a
	((SCformat *)L->Store)->rowind_colptr = Glu.xlsub;
kusano 7d535a
	((NCformat *)U->Store)->nnz = nnzU;
kusano 7d535a
	((NCformat *)U->Store)->nzval = Glu.ucol;
kusano 7d535a
	((NCformat *)U->Store)->rowind = Glu.usub;
kusano 7d535a
	((NCformat *)U->Store)->colptr = Glu.xusub;
kusano 7d535a
    } else {
kusano 7d535a
	dCreate_SuperNode_Matrix(L, A->nrow, min_mn, nnzL, Glu.lusup,
kusano 7d535a
				 Glu.xlusup, Glu.lsub, Glu.xlsub, Glu.supno,
kusano 7d535a
				 Glu.xsup, SLU_SC, SLU_D, SLU_TRLU);
kusano 7d535a
	dCreate_CompCol_Matrix(U, min_mn, min_mn, nnzU, Glu.ucol,
kusano 7d535a
			       Glu.usub, Glu.xusub, SLU_NC, SLU_D, SLU_TRU);
kusano 7d535a
    }
kusano 7d535a
kusano 7d535a
    ops[FACT] += ops[TRSV] + ops[GEMV];
kusano 7d535a
    stat->expansions = --(Glu.num_expansions);
kusano 7d535a
kusano 7d535a
    if ( iperm_r_allocated ) SUPERLU_FREE (iperm_r);
kusano 7d535a
    SUPERLU_FREE (iperm_c);
kusano 7d535a
    SUPERLU_FREE (relax_end);
kusano 7d535a
    SUPERLU_FREE (swap);
kusano 7d535a
    SUPERLU_FREE (iswap);
kusano 7d535a
    SUPERLU_FREE (relax_fsupc);
kusano 7d535a
    SUPERLU_FREE (amax);
kusano 7d535a
    if ( iwork2 ) SUPERLU_FREE (iwork2);
kusano 7d535a
kusano 7d535a
}