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/* ========================================================================== */
/* === umfpack_get_numeric ================================================== */
/* ========================================================================== */

/* -------------------------------------------------------------------------- */
/* UMFPACK Version 4.5, Copyright (c) 2005 by Timothy A. Davis.  CISE Dept,   */
/* Univ. of Florida.  All Rights Reserved.  See ../Doc/License for License.   */
/* web: http://www.cise.ufl.edu/research/sparse/umfpack                       */
/* -------------------------------------------------------------------------- */

int umfpack_di_get_numeric
(
    int Lp [ ],
    int Lj [ ],
    double Lx [ ],
    int Up [ ],
    int Ui [ ],
    double Ux [ ],
    int P [ ],
    int Q [ ],
    double Dx [ ],
    int *do_recip,
    double Rs [ ],
    void *Numeric
) ;

long umfpack_dl_get_numeric
(
    long Lp [ ],
    long Lj [ ],
    double Lx [ ],
    long Up [ ],
    long Ui [ ],
    double Ux [ ],
    long P [ ],
    long Q [ ],
    double Dx [ ],
    long *do_recip,
    double Rs [ ],
    void *Numeric
) ;

int umfpack_zi_get_numeric
(
    int Lp [ ],
    int Lj [ ],
    double Lx [ ], double Lz [ ],
    int Up [ ],
    int Ui [ ],
    double Ux [ ], double Uz [ ],
    int P [ ],
    int Q [ ],
    double Dx [ ], double Dz [ ],
    int *do_recip,
    double Rs [ ],
    void *Numeric
) ;

long umfpack_zl_get_numeric
(
    long Lp [ ],
    long Lj [ ],
    double Lx [ ], double Lz [ ],
    long Up [ ],
    long Ui [ ],
    double Ux [ ], double Uz [ ],
    long P [ ],
    long Q [ ],
    double Dx [ ], double Dz [ ],
    long *do_recip,
    double Rs [ ],
    void *Numeric
) ;

/*
double int Syntax:

    #include "umfpack.h"
    void *Numeric ;
    int *Lp, *Lj, *Up, *Ui, *P, *Q, status, do_recip ;
    double *Lx, *Ux, *Dx, *Rs ;
    status = umfpack_di_get_numeric (Lp, Lj, Lx, Up, Ui, Ux, P, Q, Dx,
    &do_recip, Rs, Numeric) ;

double long Syntax:

    #include "umfpack.h"
    void *Numeric ;
    long *Lp, *Lj, *Up, *Ui, *P, *Q, status, do_recip ;
    double *Lx, *Ux, *Dx, *Rs ;
    status = umfpack_dl_get_numeric (Lp, Lj, Lx, Up, Ui, Ux, P, Q, Dx,
    &do_recip, Rs, Numeric) ;

complex int Syntax:

    #include "umfpack.h"
    void *Numeric ;
    int *Lp, *Lj, *Up, *Ui, *P, *Q, status, do_recip ;
    double *Lx, *Lz, *Ux, *Uz, *Dx, *Dz, *Rs ;
    status = umfpack_zi_get_numeric (Lp, Lj, Lx, Lz, Up, Ui, Ux, Uz, P, Q,
    Dx, Dz, &do_recip, Rs, Numeric) ;

complex long Syntax:

    #include "umfpack.h"
    void *Numeric ;
    long *Lp, *Lj, *Up, *Ui, *P, *Q, status, do_recip ;
    double *Lx, *Lz, *Ux, *Uz, *Dx, *Dz, *Rs ;
    status = umfpack_zl_get_numeric (Lp, Lj, Lx, Lz, Up, Ui, Ux, Uz, P, Q,
    Dx, Dz, &do_recip, Rs, Numeric) ;

packed complex int/long Syntax:

    Same as above, except Lz, Uz, and Dz are all NULL.

Purpose:

    This routine copies the LU factors and permutation vectors from the Numeric
    object into user-accessible arrays.  This routine is not needed to solve a
    linear system.  Note that the output arrays Lp, Lj, Lx, Up, Ui, Ux, P, Q,
    Dx, and Rs are not allocated by umfpack_*_get_numeric; they must exist on
    input.

    All output arguments are optional.  If any of them are NULL
    on input, then that part of the LU factorization is not copied.  You can
    use this routine to extract just the parts of the LU factorization that
    you want.  For example, to retrieve just the column permutation Q, use:

    #define noD (double *) NULL
    #define noI (int *) NULL
    status = umfpack_di_get_numeric (noI, noI, noD, noI, noI, noD, noI,
    Q, noD, noI, noD, Numeric) ;

Returns:

    Returns UMFPACK_OK if successful.  Returns UMFPACK_ERROR_out_of_memory
    if insufficient memory is available for the 2*max(n_row,n_col) integer
    workspace that umfpack_*_get_numeric allocates to construct L and/or U.
    Returns UMFPACK_ERROR_invalid_Numeric_object if the Numeric object provided
    as input is invalid.

Arguments:

    Int Lp [n_row+1] ;  Output argument.
    Int Lj [lnz] ;  Output argument.
    double Lx [lnz] ;   Output argument.  Size 2*lnz for packed complex case.
    double Lz [lnz] ;   Output argument for complex versions.

    The n_row-by-min(n_row,n_col) matrix L is returned in compressed-row
    form.  The column indices of row i and corresponding numerical values
    are in:

        Lj [Lp [i] ... Lp [i+1]-1]
        Lx [Lp [i] ... Lp [i+1]-1]  real part
        Lz [Lp [i] ... Lp [i+1]-1]  imaginary part (complex versions)

    respectively.  Each row is stored in sorted order, from low column
    indices to higher.  The last entry in each row is the diagonal, which
    is numerically equal to one.  The sizes of Lp, Lj, Lx, and Lz are
    returned by umfpack_*_get_lunz.    If Lp, Lj, or Lx are not present,
    then the matrix L is not returned.  This is not an error condition.
    The L matrix can be printed if n_row, Lp, Lj, Lx (and Lz for the split
    complex case) are passed to umfpack_*_report_matrix (using the
    "row" form).

    If Lx is present and Lz is NULL, then both real
    and imaginary parts are returned in Lx[0..2*lnz-1], with Lx[2*k]
    and Lx[2*k+1] being the real and imaginary part of the kth entry.

    Int Up [n_col+1] ;  Output argument.
    Int Ui [unz] ;  Output argument.
    double Ux [unz] ;   Output argument. Size 2*unz for packed complex case.
    double Uz [unz] ;   Output argument for complex versions.

    The min(n_row,n_col)-by-n_col matrix U is returned in compressed-column
    form.  The row indices of column j and corresponding numerical values
    are in

        Ui [Up [j] ... Up [j+1]-1]
        Ux [Up [j] ... Up [j+1]-1]  real part
        Uz [Up [j] ... Up [j+1]-1]  imaginary part (complex versions)

    respectively.  Each column is stored in sorted order, from low row
    indices to higher.  The last entry in each column is the diagonal
    (assuming that it is nonzero).  The sizes of Up, Ui, Ux, and Uz are
    returned by umfpack_*_get_lunz.  If Up, Ui, or Ux are not present,
    then the matrix U is not returned.  This is not an error condition.
    The U matrix can be printed if n_col, Up, Ui, Ux (and Uz for the
    split complex case) are passed to umfpack_*_report_matrix (using the
    "column" form).

    If Ux is present and Uz is NULL, then both real
    and imaginary parts are returned in Ux[0..2*unz-1], with Ux[2*k]
    and Ux[2*k+1] being the real and imaginary part of the kth entry.

    Int P [n_row] ;     Output argument.

    The permutation vector P is defined as P [k] = i, where the original
    row i of A is the kth pivot row in PAQ.  If you do not want the P vector
    to be returned, simply pass (Int *) NULL for P.  This is not an error
    condition.  You can print P and Q with umfpack_*_report_perm.

    Int Q [n_col] ;     Output argument.

    The permutation vector Q is defined as Q [k] = j, where the original
    column j of A is the kth pivot column in PAQ.  If you not want the Q
    vector to be returned, simply pass (Int *) NULL for Q.  This is not
    an error condition.  Note that Q is not necessarily identical to
    Qtree, the column pre-ordering held in the Symbolic object.  Refer to
    the description of Qtree and Front_npivcol in umfpack_*_get_symbolic for
    details.

    double Dx [min(n_row,n_col)] ;  Output argument.  Size 2*n for
                    the packed complex case.
    double Dz [min(n_row,n_col)] ;  Output argument for complex versions.

    The diagonal of U is also returned in Dx and Dz.  You can extract the
    diagonal of U without getting all of U by passing a non-NULL Dx (and
    Dz for the complex version) and passing Up, Ui, and Ux as NULL.  Dx is
    the real part of the diagonal, and Dz is the imaginary part.

    If Dx is present and Dz is NULL, then both real
    and imaginary parts are returned in Dx[0..2*min(n_row,n_col)-1],
    with Dx[2*k] and Dx[2*k+1] being the real and imaginary part of the kth
    entry.

    Int *do_recip ;     Output argument.

    If do_recip is returned as zero (false), then the scale factors Rs [i]
    are to be used by multiplying row i by Rs [i].  Otherwise, the entries
    in row i are to be divided by Rs [i].

    If UMFPACK has been compiled with gcc, or for MATLAB as either a
    built-in routine or as a mexFunction, then the NRECIPROCAL flag is
    set, and do_recip will always be zero (false).

    double Rs [n_row] ;     Output argument.

    The row scale factors are returned in Rs [0..n_row-1].  Row i of A is
    scaled by dividing or multiplying its values by Rs [i].  If default
    scaling is in use, Rs [i] is the sum of the absolute values of row i
    (or its reciprocal).  If max row scaling is in use, then Rs [i] is the
    maximum absolute value in row i (or its reciprocal).
    Otherwise, Rs [i] = 1.  If row i is all zero, Rs [i] = 1 as well.  For
    the complex version, an approximate absolute value is used
    (|x_real|+|x_imag|).

    void *Numeric ; Input argument, not modified.

    Numeric must point to a valid Numeric object, computed by
    umfpack_*_numeric.
*/