Beispiel #1
0
GLOBAL Int AMD_order
(
    Int n,
    const Int Ap [ ],
    const Int Ai [ ],
    Int P [ ],
    double Control [ ],
    double Info [ ]
)
{
    Int slen, *Len, *S, nz, nzaat, i, *Pinv, info ;

#ifndef NDEBUG
    AMD_debug_init ("amd") ;
#endif

    /* clear the Info array, if it exists */
    info = Info != (double *) NULL ;
    if (info)
    {
	for (i = 0 ; i < AMD_INFO ; i++)
	{
	    Info [i] = EMPTY ;
	}
	Info [AMD_N] = n ;
	Info [AMD_STATUS] = AMD_OK ;
    }

    /* make sure inputs exist and n is >= 0 */
    if (Ai == (Int *) NULL || Ap == (Int *) NULL || P == (Int *) NULL || n < 0)
    {
	if (info) Info [AMD_STATUS] = AMD_INVALID ;
	return (AMD_INVALID) ;	    /* arguments are invalid */
    }

    if (n == 0)
    {
	return (AMD_OK) ;	    /* n is 0 so there's nothing to do */
    }

    nz = Ap [n] ;
    if (info)
    {
	Info [AMD_NZ] = nz ;
    }
    if (nz < 0)
    {
	if (info) Info [AMD_STATUS] = AMD_INVALID ;
	return (AMD_INVALID) ;
    }

    /* Avoid integer overflow in memory size calculations.  The space required
     * by AMD is at most 2.4nz + 8n for S, and n for Len.
     * Note nz - n <= nzaat <= 2*nz, below. */
    if ((2.4 * (double) nz + 8 * (double) n) > (double) Int_MAX / sizeof (Int))
    {
	/* :: int overflow :: */
	if (info) Info [AMD_STATUS] = AMD_OUT_OF_MEMORY ;
	return (AMD_OUT_OF_MEMORY) ;
    }

    if (!AMD_valid (n, n, Ap, Ai))
    {
	if (info) Info [AMD_STATUS] = AMD_INVALID ;
	return (AMD_INVALID) ;	    /* matrix is invalid */
    }

    /* --------------------------------------------------------------------- */
    /* determine the symmetry and count off-diagonal nonzeros in A+A' */
    /* --------------------------------------------------------------------- */

    /* allocate size-n integer workspace */
    Len = (Int *) amd_malloc (n * sizeof (Int)) ;
    if (!Len)
    {
	/* :: out of memory :: */
	if (info) Info [AMD_STATUS] = AMD_OUT_OF_MEMORY ;
	return (AMD_OUT_OF_MEMORY) ;
    }
    nzaat = AMD_aat (n, Ap, Ai, Len, P, Info) ;
    AMD_DEBUG1 (("nzaat: "ID"\n", nzaat)) ;
    ASSERT (nz-n <= nzaat && nzaat <= 2*nz) ;

    /* --------------------------------------------------------------------- */
    /* allocate workspace for matrix, elbow room, and 7 size-n vectors */
    /* --------------------------------------------------------------------- */

    slen = (nzaat + nzaat/5 + n) + 7*n ;
    if (info)
    {
	/* memory usage (Len and S), in bytes. */
	Info [AMD_MEMORY] = ((double) slen + n) * sizeof (Int) ;
    }
    S = (Int *) amd_malloc (slen * sizeof (Int)) ;
    AMD_DEBUG1 ((" S "ID" Len "ID" n "ID" nzaat "ID" slen "ID"\n",
	(Int) S, (Int) Len, n, nzaat, slen)) ;
    if (S == (Int *) NULL)
    {
	/* :: out of memory :: */
	amd_free (Len) ;
	if (Info != (double *) NULL) Info [AMD_STATUS] = AMD_OUT_OF_MEMORY ;
	return (AMD_OUT_OF_MEMORY) ;
    }

    /* allocate space from S for Pinv */
    Pinv = S + slen - n ;
    slen -= n ;

    /* --------------------------------------------------------------------- */
    /* order the matrix */
    /* --------------------------------------------------------------------- */

    AMD_1 (n, Ap, Ai, P, Pinv, Len, slen, S, Control, Info) ;

    /* --------------------------------------------------------------------- */
    /* free the workspace */
    /* --------------------------------------------------------------------- */

    amd_free (Len) ;
    amd_free (S) ;
    return (AMD_OK) ;	    /* successful ordering */
}
GLOBAL void AMD_preprocess
(
    Int n,		/* input matrix: A is n-by-n */
    const Int Ap [ ],	/* size n+1 */
    const Int Ai [ ],	/* size nz = Ap [n] */

    /* output matrix R: */
    Int Rp [ ],		/* size n+1 */
    Int Ri [ ],		/* size nz (or less, if duplicates present) */

    Int W [ ],		/* workspace of size n */
    Int Flag [ ]	/* workspace of size n */
)
{

    /* --------------------------------------------------------------------- */
    /* local variables */
    /* --------------------------------------------------------------------- */

    Int i, j, p, p2 ;

    ASSERT (AMD_valid (n, n, Ap, Ai) != AMD_INVALID) ;

    /* --------------------------------------------------------------------- */
    /* count the entries in each row of A (excluding duplicates) */
    /* --------------------------------------------------------------------- */

    for (i = 0 ; i < n ; i++)
    {
	W [i] = 0 ;		/* # of nonzeros in row i (excl duplicates) */
	Flag [i] = EMPTY ;	/* Flag [i] = j if i appears in column j */
    }
    for (j = 0 ; j < n ; j++)
    {
	p2 = Ap [j+1] ;
	for (p = Ap [j] ; p < p2 ; p++)
	{
	    i = Ai [p] ;
	    if (Flag [i] != j)
	    {
		/* row index i has not yet appeared in column j */
		W [i]++ ;	    /* one more entry in row i */
		Flag [i] = j ;	    /* flag row index i as appearing in col j*/
	    }
	}
    }

    /* --------------------------------------------------------------------- */
    /* compute the row pointers for R */
    /* --------------------------------------------------------------------- */

    Rp [0] = 0 ;
    for (i = 0 ; i < n ; i++)
    {
	Rp [i+1] = Rp [i] + W [i] ;
    }
    for (i = 0 ; i < n ; i++)
    {
	W [i] = Rp [i] ;
	Flag [i] = EMPTY ;
    }

    /* --------------------------------------------------------------------- */
    /* construct the row form matrix R */
    /* --------------------------------------------------------------------- */

    /* R = row form of pattern of A */
    for (j = 0 ; j < n ; j++)
    {
	p2 = Ap [j+1] ;
	for (p = Ap [j] ; p < p2 ; p++)
	{
	    i = Ai [p] ;
	    if (Flag [i] != j)
	    {
		/* row index i has not yet appeared in column j */
		Ri [W [i]++] = j ;  /* put col j in row i */
		Flag [i] = j ;	    /* flag row index i as appearing in col j*/
	    }
	}
    }

#ifndef NDEBUG
    ASSERT (AMD_valid (n, n, Rp, Ri) == AMD_OK) ;
    for (j = 0 ; j < n ; j++)
    {
	ASSERT (W [j] == Rp [j+1]) ;
    }
#endif
}
PRIVATE Int two_by_two	    /* returns # unmatched weak diagonals */
(
    /* input, not modified */
    Int n2,		/* C is n2-by-n2 */
    Int Cp [ ],		/* size n2+1, column pointers for C */
    Int Ci [ ],		/* size snz = Cp [n2], row indices for C */
    Int Degree [ ],	/* Degree [i] = degree of row i of C+C' */

    /* input, not defined on output */
    Int Next [ ],	/* Next [k] == IS_WEAK if k is a weak diagonal */
    Int Ri [ ],		/* Ri [i] is the length of row i in C */

    /* output, not defined on input */
    Int P [ ],

    /* workspace, not defined on input or output */
    Int Rp [ ],
    Int Head [ ]
)
{
    Int deg, newcol, row, col, p, p2, unmatched, k, j, j2, j_best, best, jdiff,
	jdiff_best, jdeg, jdeg_best, cp, cp1, cp2, rp, rp1, rp2, maxdeg,
	mindeg ;

    /* ---------------------------------------------------------------------- */
    /* place weak diagonals in the degree lists */
    /* ---------------------------------------------------------------------- */

    for (deg = 0 ; deg < n2 ; deg++)
    {
	Head [deg] = EMPTY ;
    }

    maxdeg = 0 ;
    mindeg = Int_MAX ;
    for (newcol = n2-1 ; newcol >= 0 ; newcol--)
    {
	if (Next [newcol] == IS_WEAK)
	{
	    /* add this column to the list of weak nodes */
	    DEBUGm1 (("    newcol "ID" has a weak diagonal deg "ID"\n",
		newcol, deg)) ;
	    deg = Degree [newcol] ;
	    ASSERT (deg >= 0 && deg < n2) ;
	    Next [newcol] = Head [deg] ;
	    Head [deg] = newcol ;
	    maxdeg = MAX (maxdeg, deg) ;
	    mindeg = MIN (mindeg, deg) ;
	}
    }

    /* ---------------------------------------------------------------------- */
    /* construct R = C' (C = strong entries in pruned submatrix) */
    /* ---------------------------------------------------------------------- */

    /* Ri [0..n2-1] is the length of each row of R */
    /* use P as temporary pointer into the row form of R [ */
    Rp [0] = 0 ;
    for (row = 0 ; row < n2 ; row++)
    {
	Rp [row+1] = Rp [row] + Ri [row] ;
	P [row] = Rp [row] ;
    }
    /* Ri no longer needed for row counts */

    /* all entries in C are strong */
    for (col = 0 ; col < n2 ; col++)
    {
	p2 = Cp [col+1] ;
	for (p = Cp [col] ; p < p2 ; p++)
	{
	    /* place the column index in row = Ci [p] */
	    Ri [P [Ci [p]]++] = col ;
	}
    }

    /* contents of P no longer needed ] */

#ifndef NDEBUG
    DEBUG0 (("==================R: row form of strong entries in A:\n")) ;
    UMF_dump_col_matrix ((double *) NULL,
#ifdef COMPLEX
	    (double *) NULL,
#endif
	    Ri, Rp, n2, n2, Rp [n2]) ;
#endif
    ASSERT (AMD_valid (n2, n2, Rp, Ri) == AMD_OK) ;

    /* ---------------------------------------------------------------------- */
    /* for each weak diagonal, find a pair of strong off-diagonal entries */
    /* ---------------------------------------------------------------------- */

    for (row = 0 ; row < n2 ; row++)
    {
	P [row] = EMPTY ;
    }

    unmatched = 0 ;
    best = EMPTY ;
    jdiff = EMPTY ;
    jdeg = EMPTY ;

    for (deg = mindeg ; deg <= maxdeg ; deg++)
    {
	/* find the next weak diagonal of lowest degree */
	DEBUGm2 (("---------------------------------- Deg: "ID"\n", deg)) ;
	for (k = Head [deg] ; k != EMPTY ; k = Next [k])
	{
	    DEBUGm2 (("k: "ID"\n", k)) ;
	    if (P [k] == EMPTY)
	    {
		/* C (k,k) is a weak diagonal entry.  Find an index j != k such
		 * that C (j,k) and C (k,j) are both strong, and also such
		 * that Degree [j] is minimized.  In case of a tie, pick
		 * the smallest index j.  C and R contain the pattern of
		 * strong entries only.
		 *
		 * Note that row k of R and column k of C are both sorted. */

		DEBUGm4 (("===== Weak diagonal k = "ID"\n", k)) ;
		DEBUG1 (("Column k of C:\n")) ;
		for (p = Cp [k] ; p < Cp [k+1] ; p++)
		{
		    DEBUG1 (("    "ID": deg "ID"\n", Ci [p], Degree [Ci [p]]));
		}
		DEBUG1 (("Row k of R (strong entries only):\n")) ;
		for (p = Rp [k] ; p < Rp [k+1] ; p++)
		{
		    DEBUG1 (("    "ID": deg "ID"\n", Ri [p], Degree [Ri [p]]));
		}

		/* no (C (k,j), C (j,k)) pair exists yet */
		j_best = EMPTY ;
		jdiff_best = Int_MAX ;
		jdeg_best = Int_MAX ;

		/* pointers into column k (including values) */
		cp1 = Cp [k] ;
		cp2 = Cp [k+1] ;
		cp = cp1 ;

		/* pointers into row k (strong entries only, no values) */
		rp1 = Rp [k] ;
		rp2 = Rp [k+1] ;
		rp = rp1 ;

		/* while entries searched in column k and row k */
		while (TRUE)
		{

		    if (cp >= cp2)
		    {
			/* no more entries in this column */
			break ;
		    }

		    /* get C (j,k), which is strong */
		    j = Ci [cp] ;

		    if (rp >= rp2)
		    {
			/* no more entries in this column */
			break ;
		    }

		    /* get R (k,j2), which is strong */
		    j2 = Ri [rp] ;

		    if (j < j2)
		    {
			/* C (j,k) is strong, but R (k,j) is not strong */
			cp++ ;
			continue ;
		    }

		    if (j2 < j)
		    {
			/* C (k,j2) is strong, but R (j2,k) is not strong */
			rp++ ;
			continue ;
		    }

		    /* j == j2: C (j,k) is strong and R (k,j) is strong */

		    best = FALSE ;

		    if (P [j] == EMPTY)
		    {
			/* j has not yet been matched */
			jdeg = Degree [j] ;
			jdiff = SCALAR_ABS (k-j) ;

			DEBUG1 (("Try candidate j "ID" deg "ID" diff "ID
				    "\n", j, jdeg, jdiff)) ;

			if (j_best == EMPTY)
			{
			    /* this is the first candidate seen */
			    DEBUG1 (("   first\n")) ;
			    best = TRUE ;
			}
			else
			{
			    if (jdeg < jdeg_best)
			    {
				/* the degree of j is best seen so far. */
				DEBUG1 (("   least degree\n")) ;
				best = TRUE ;
			    }
			    else if (jdeg == jdeg_best)
			    {
				/* degree of j and j_best are the same */
				/* tie break by nearest node number */
				if (jdiff < jdiff_best)
				{
				    DEBUG1 (("   tie degree, closer\n")) ;
				    best = TRUE ;
				}
				else if (jdiff == jdiff_best)
				{
				    /* |j-k| = |j_best-k|.  For any given k
				     * and j_best there is only one other j
				     * than can be just as close as j_best.
				     * Tie break by picking the smaller of
				     * j and j_best */
				    DEBUG1 (("   tie degree, as close\n"));
				    best = j < j_best ;
				}
			    }
			    else
			    {
				/* j has higher degree than best so far */
				best = FALSE ;
			    }
			}
		    }

		    if (best)
		    {
			/* j is best match for k */
			/* found a strong pair, A (j,k) and A (k,j) */
			DEBUG1 ((" --- Found pair k: "ID" j: " ID
			    " jdeg: "ID" jdiff: "ID"\n",
			    k, j, jdeg, jdiff)) ;
			ASSERT (jdiff != EMPTY) ;
			ASSERT (jdeg != EMPTY) ;
			j_best = j ;
			jdeg_best = jdeg ;
			jdiff_best = jdiff ;
		    }

		    /* get the next entries in column k and row k */
		    cp++ ;
		    rp++ ;
		}

		/* save the pair (j,k), if we found one */
		if (j_best != EMPTY)
		{
		    j = j_best ;
		    DEBUGm4 ((" --- best pair j: "ID" for k: "ID"\n", j, k)) ;
		    P [k] = j ;
		    P [j] = k ;
		}
		else
		{
		    /* no match was found for k */
		    unmatched++ ;
		}
	    }
	}
    }

    /* ---------------------------------------------------------------------- */
    /* finalize the row permutation, P */
    /* ---------------------------------------------------------------------- */

    for (k = 0 ; k < n2 ; k++)
    {
	if (P [k] == EMPTY)
	{
	    P [k] = k ;
	}
    }
    ASSERT (UMF_is_permutation (P, Rp, n2, n2)) ;

    return (unmatched) ;
}
Beispiel #4
0
void amdtest (cholmod_sparse *A)
{
    double Control [AMD_CONTROL], Info [AMD_INFO], alpha ;
    Int *P, *Cp, *Ci, *Sp, *Si, *Bp, *Bi, *Ep, *Ei, *Fp, *Fi,
	*Len, *Nv, *Next, *Head, *Elen, *Deg, *Wi, *W, *Flag ;
    cholmod_sparse *C, *B, *S, *E, *F ;
    Int i, j, n, nrow, ncol, ok, cnz, bnz, p, trial, sorted ;

    /* ---------------------------------------------------------------------- */
    /* get inputs */
    /* ---------------------------------------------------------------------- */

    printf ("\nAMD test\n") ;

    if (A == NULL)
    {
	return ;
    }

    if (A->stype)
    {
	B = CHOLMOD(copy) (A, 0, 0, cm) ;
    }
    else
    {
	B = CHOLMOD(aat) (A, NULL, 0, 0, cm) ;
    }

    if (A->nrow != A->ncol)
    {
	F = CHOLMOD(copy_sparse) (B, cm) ;
	OK (F->nrow == F->ncol) ;
	CHOLMOD(sort) (F, cm) ;
    }
    else
    {
	/* A is square and unsymmetric, and may have entries in A+A' that
	 * are not in A */
	F = CHOLMOD(copy_sparse) (A, cm) ;
	CHOLMOD(sort) (F, cm) ;
    }

    C = CHOLMOD(copy_sparse) (B, cm) ;

    nrow = C->nrow ;
    ncol = C->ncol ;
    n = nrow ;
    OK (nrow == ncol) ;

    Cp = C->p ;
    Ci = C->i ;

    Bp = B->p ;
    Bi = B->i ;

    /* ---------------------------------------------------------------------- */
    /* S = sorted form of B, using AMD_preprocess */
    /* ---------------------------------------------------------------------- */

    cnz = CHOLMOD(nnz) (C, cm) ;
    S = CHOLMOD(allocate_sparse) (n, n, cnz, TRUE, TRUE, 0, CHOLMOD_PATTERN,
	    cm);
    Sp = S->p ;
    Si = S->i ;

    W = CHOLMOD(malloc) (n, sizeof (Int), cm) ;
    Flag = CHOLMOD(malloc) (n, sizeof (Int), cm) ;
    AMD_preprocess (n, Bp, Bi, Sp, Si, W, Flag) ;

    /* ---------------------------------------------------------------------- */
    /* allocate workspace for amd */
    /* ---------------------------------------------------------------------- */

    P = CHOLMOD(malloc) (n+1, sizeof (Int), cm) ;

    Len  = CHOLMOD(malloc) (n, sizeof (Int), cm) ;
    Nv   = CHOLMOD(malloc) (n, sizeof (Int), cm) ;
    Next = CHOLMOD(malloc) (n, sizeof (Int), cm) ;
    Head = CHOLMOD(malloc) (n+1, sizeof (Int), cm) ;
    Elen = CHOLMOD(malloc) (n, sizeof (Int), cm) ;
    Deg  = CHOLMOD(malloc) (n, sizeof (Int), cm) ;
    Wi   = CHOLMOD(malloc) (n, sizeof (Int), cm) ;

    /* ---------------------------------------------------------------------- */

    for (sorted = 0 ; sorted <= 1 ; sorted++)
    {

	if (sorted) CHOLMOD(sort) (C, cm) ;

	Cp = C->p ;
	Ci = C->i ;

	/* ------------------------------------------------------------------ */
	/* order C with AMD_order */
	/* ------------------------------------------------------------------ */

	AMD_defaults (Control) ;
	AMD_defaults (NULL) ;
	AMD_control (Control) ;
	AMD_control (NULL) ;
	AMD_info (NULL) ;

	ok = AMD_order (n, Cp, Ci, P, Control, Info) ;
	printf ("amd return value: "ID"\n", ok) ;
	AMD_info (Info) ;
	OK (sorted ? (ok == AMD_OK) : (ok >= AMD_OK)) ;
	OK (CHOLMOD(print_perm) (P, n, n, "AMD permutation", cm)) ;

	/* no dense rows/cols */
	alpha = Control [AMD_DENSE] ;
	Control [AMD_DENSE] = -1 ;
	AMD_control (Control) ;
	ok = AMD_order (n, Cp, Ci, P, Control, Info) ;
	printf ("amd return value: "ID"\n", ok) ;
	AMD_info (Info) ;
	OK (sorted ? (ok == AMD_OK) : (ok >= AMD_OK)) ;
	OK (CHOLMOD(print_perm) (P, n, n, "AMD permutation (alpha=-1)", cm)) ;

	/* many dense rows/cols */
	Control [AMD_DENSE] = 0 ;
	AMD_control (Control) ;
	ok = AMD_order (n, Cp, Ci, P, Control, Info) ;
	printf ("amd return value: "ID"\n", ok) ;
	AMD_info (Info) ;
	OK (sorted ? (ok == AMD_OK) : (ok >= AMD_OK)) ;
	OK (CHOLMOD(print_perm) (P, n, n, "AMD permutation (alpha=0)", cm)) ;
	Control [AMD_DENSE] = alpha ;

	/* no aggressive absorption */
	Control [AMD_AGGRESSIVE] = FALSE ;
	AMD_control (Control) ;
	ok = AMD_order (n, Cp, Ci, P, Control, Info) ;
	printf ("amd return value: "ID"\n", ok) ;
	AMD_info (Info) ;
	OK (sorted ? (ok == AMD_OK) : (ok >= AMD_OK)) ;
	OK (CHOLMOD(print_perm) (P, n, n, "AMD permutation (no agg) ", cm)) ;
	Control [AMD_AGGRESSIVE] = TRUE ;

	/* ------------------------------------------------------------------ */
	/* order F with AMD_order */
	/* ------------------------------------------------------------------ */

	Fp = F->p ;
	Fi = F->i ;
	ok = AMD_order (n, Fp, Fi, P, Control, Info) ;
	printf ("amd return value: "ID"\n", ok) ;
	AMD_info (Info) ;
	OK (sorted ? (ok == AMD_OK) : (ok >= AMD_OK)) ;
	OK (CHOLMOD(print_perm) (P, n, n, "F: AMD permutation", cm)) ;

	/* ------------------------------------------------------------------ */
	/* order S with AMD_order */
	/* ------------------------------------------------------------------ */

	ok = AMD_order (n, Sp, Si, P, Control, Info) ;
	printf ("amd return value: "ID"\n", ok) ;
	AMD_info (Info) ;
	OK (sorted ? (ok == AMD_OK) : (ok >= AMD_OK)) ;
	OK (CHOLMOD(print_perm) (P, n, n, "AMD permutation", cm)) ;

	/* ------------------------------------------------------------------ */
	/* order E with AMD_2, which destroys its contents */
	/* ------------------------------------------------------------------ */

	E = CHOLMOD(copy) (B, 0, -1, cm) ;	/* remove diagonal entries */
	bnz = CHOLMOD(nnz) (E, cm) ;

	/* add the bare minimum extra space to E */
	ok = CHOLMOD(reallocate_sparse) (bnz + n, E, cm) ;
	OK (ok) ;
	Ep = E->p ;
	Ei = E->i ;

	for (j = 0 ; j < n ; j++)
	{
	    Len [j] = Ep [j+1] - Ep [j] ;
	}

	printf ("calling AMD_2:\n") ;
	if (n > 0)
	{
	    AMD_2 (n, Ep, Ei, Len, E->nzmax, Ep [n], Nv, Next, P, Head, Elen,
		Deg, Wi, Control, Info) ;
	    AMD_info (Info) ;
	    OK (CHOLMOD(print_perm) (P, n, n, "AMD2 permutation", cm)) ;
	}

	/* ------------------------------------------------------------------ */
	/* error tests */
	/* ------------------------------------------------------------------ */

	ok = AMD_order (n, Cp, Ci, P, Control, Info) ;
	OK (sorted ? (ok == AMD_OK) : (ok >= AMD_OK)) ;
	ok = AMD_order (-1, Cp, Ci, P, Control, Info) ;
	OK (ok == AMD_INVALID);
	ok = AMD_order (0, Cp, Ci, P, Control, Info) ;
	OK (sorted ? (ok == AMD_OK) : (ok >= AMD_OK)) ;
	ok = AMD_order (n, NULL, Ci, P, Control, Info) ;
	OK (ok == AMD_INVALID);
	ok = AMD_order (n, Cp, NULL, P, Control, Info) ;
	OK (ok == AMD_INVALID);
	ok = AMD_order (n, Cp, Ci, NULL, Control, Info) ;
	OK (ok == AMD_INVALID);

	if (n > 0)
	{
	    printf ("AMD error tests:\n") ;

	    p = Cp [n] ;
	    Cp [n] = -1 ;
	    ok = AMD_order (n, Cp, Ci, P, Control, Info) ;
	    OK (ok == AMD_INVALID) ;

	    if (Size_max/2 == Int_max)
	    {
		Cp [n] = Int_max ;
		ok = AMD_order (n, Cp, Ci, P, Control, Info) ;
		printf ("AMD status is "ID"\n", ok) ;
		OK (ok == AMD_OUT_OF_MEMORY) ;
	    }

	    Cp [n] = p ;
	    ok = AMD_order (n, Cp, Ci, P, Control, Info) ;
	    OK (sorted ? (ok == AMD_OK) : (ok >= AMD_OK)) ;
	    if (Cp [n] > 0)
	    {
		printf ("Mangle column zero:\n") ;
		i = Ci [0] ;
		Ci [0] = -1 ;
		ok = AMD_order (n, Cp, Ci, P, Control, Info) ;
		AMD_info (Info) ;
		OK (ok == AMD_INVALID) ;
		Ci [0] = i ;
	    }
	}

	ok = AMD_valid (n, n, Sp, Si) ;
	OK (sorted ? (ok == AMD_OK) : (ok >= AMD_OK)) ;
	ok = AMD_valid (-1, n, Sp, Si) ;	    OK (ok == AMD_INVALID) ;
	ok = AMD_valid (n, -1, Sp, Si) ;	    OK (ok == AMD_INVALID) ;
	ok = AMD_valid (n, n, NULL, Si) ;	    OK (ok == AMD_INVALID) ;
	ok = AMD_valid (n, n, Sp, NULL) ;	    OK (ok == AMD_INVALID) ;

	if (n > 0 && Sp [n] > 0)
	{

	    p = Sp [n] ;
	    Sp [n] = -1 ;
	    ok = AMD_valid (n, n, Sp, Si) ; OK (ok == AMD_INVALID) ;
	    Sp [n] = p ;

	    p = Sp [0] ;
	    Sp [0] = -1 ;
	    ok = AMD_valid (n, n, Sp, Si) ; OK (ok == AMD_INVALID) ;
	    Sp [0] = p ;

	    p = Sp [1] ;
	    Sp [1] = -1 ;
	    ok = AMD_valid (n, n, Sp, Si) ; OK (ok == AMD_INVALID) ;
	    Sp [1] = p ;

	    i = Si [0] ;
	    Si [0] = -1 ;
	    ok = AMD_valid (n, n, Sp, Si) ; OK (ok == AMD_INVALID) ;
	    Si [0] = i ;

	}

	ok = AMD_valid (n, n, Sp, Si) ;
	OK (sorted ? (ok == AMD_OK) : (ok >= AMD_OK)) ;
	AMD_preprocess (n, Bp, Bi, Sp, Si, W, Flag) ;
	ok = AMD_valid (n, n, Sp, Si) ;
	OK (ok == AMD_OK) ;

	if (n > 0 && Bp [n] > 0)
	{

	    p = Bp [n] ;
	    Bp [n] = -1 ;
	    ok = AMD_valid (n, n, Bp, Bi) ;	    OK (ok == AMD_INVALID) ;
	    Bp [n] = p ;


	    p = Bp [1] ;
	    Bp [1] = -1 ;
	    ok = AMD_valid (n, n, Bp, Bi) ;	    OK (ok == AMD_INVALID) ;
	    Bp [1] = p ;

	    i = Bi [0] ;
	    Bi [0] = -1 ;
	    ok = AMD_valid (n, n, Bp, Bi) ;	    OK (ok == AMD_INVALID) ;
	    Bi [0] = i ;
	}

	AMD_preprocess (n, Bp, Bi, Sp, Si, W, Flag) ;

	Info [AMD_STATUS] = 777 ;
	AMD_info (Info) ;

	/* ------------------------------------------------------------------ */
	/* memory tests */
	/* ------------------------------------------------------------------ */

	if (n > 0)
	{
	    amd_malloc = cm->malloc_memory ;
	    amd_free = cm->free_memory ;
	    ok = AMD_order (n, Cp, Ci, P, Control, Info) ;
	    OK (sorted ? (ok == AMD_OK) : (ok >= AMD_OK)) ;

	    test_memory_handler ( ) ;
	    amd_malloc = cm->malloc_memory ;
	    amd_free = cm->free_memory ;
	    for (trial = 0 ; trial < 6 ; trial++)
	    {
		my_tries = trial ;
		printf ("AMD memory trial "ID"\n", trial) ;
		ok = AMD_order (n, Cp, Ci, P, Control, Info) ;
		AMD_info (Info) ;
		OK (ok == AMD_OUT_OF_MEMORY
		    || (sorted ? (ok == AMD_OK) : (ok >= AMD_OK))) ;
	    }
	    normal_memory_handler ( ) ;
	    OK (CHOLMOD(print_perm) (P, n, n, "AMD2 permutation", cm)) ;

	    amd_malloc = cm->malloc_memory ;
	    amd_free = cm->free_memory ;
	}

	CHOLMOD(free_sparse) (&E, cm) ;
    }

    /* ---------------------------------------------------------------------- */
    /* free everything */
    /* ---------------------------------------------------------------------- */

    CHOLMOD(free) (n, sizeof (Int), Len,  cm) ;
    CHOLMOD(free) (n, sizeof (Int), Nv,   cm) ;
    CHOLMOD(free) (n, sizeof (Int), Next, cm) ;
    CHOLMOD(free) (n+1, sizeof (Int), Head, cm) ;
    CHOLMOD(free) (n, sizeof (Int), Elen, cm) ;
    CHOLMOD(free) (n, sizeof (Int), Deg,  cm) ;
    CHOLMOD(free) (n, sizeof (Int), Wi,   cm) ;

    CHOLMOD(free) (n+1, sizeof (Int), P, cm) ;

    CHOLMOD(free) (n, sizeof (Int), W, cm) ;
    CHOLMOD(free) (n, sizeof (Int), Flag, cm) ;

    CHOLMOD(free_sparse) (&S, cm) ;
    CHOLMOD(free_sparse) (&B, cm) ;
    CHOLMOD(free_sparse) (&C, cm) ;
    CHOLMOD(free_sparse) (&F, cm) ;
}
GLOBAL void UMF_2by2
(
    /* input, not modified: */
    Int n,		    /* A is n-by-n */
    const Int Ap [ ],	    /* size n+1 */
    const Int Ai [ ],	    /* size nz = Ap [n] */
    const double Ax [ ],    /* size nz if present */
#ifdef COMPLEX
    const double Az [ ],    /* size nz if present */
#endif
    double tol,		/* tolerance for determining whether or not an
			 * entry is numerically acceptable.  If tol <= 0
			 * then all numerical values ignored. */
    Int scale,		/* scaling to perform (none, sum, or max) */
    Int Cperm1 [ ],	/* singleton permutations */
#ifndef NDEBUG
    Int Rperm1 [ ],	/* not needed, since Rperm1 = Cperm1 for submatrix S */
#endif
    Int InvRperm1 [ ],	/* inverse of Rperm1 */
    Int n1,		/* number of singletons */
    Int nempty,		/* number of empty rows/cols */

    /* input, contents undefined on output: */
    Int Degree [ ],	/* Degree [j] is the number of off-diagonal
			 * entries in row/column j of S+S', where
			 * where S = A (Cperm1 [n1..], Rperm1 [n1..]).
			 * Note that S is not used, nor formed. */

    /* output: */
    Int P [ ],		/* P [k] = i means original row i is kth row in S(P,:)
			 * where S = A (Cperm1 [n1..], Rperm1 [n1..]) */
    Int *p_nweak,
    Int *p_unmatched,

    /* workspace (not defined on input or output): */
    Int Ri [ ],		/* of size >= max (nz, n) */
    Int Rp [ ],		/* of size n+1 */
    double Rs [ ],	/* of size n if present.  Rs = sum (abs (A),2) or
			 * max (abs (A),2), the sum or max of each row.  Unused
			 * if scale is equal to UMFPACK_SCALE_NONE. */
    Int Head [ ],	/* of size n.  Head pointers for bucket sort */
    Int Next [ ],	/* of size n.  Next pointers for bucket sort */
    Int Ci [ ],		/* size nz */
    Int Cp [ ]		/* size n+1 */
)
{

    /* ---------------------------------------------------------------------- */
    /* local variables */
    /* ---------------------------------------------------------------------- */

    Entry aij ;
    double cmax, value, rs, ctol, dvalue ;
    Int k, p, row, col, do_values, do_sum, do_max, do_scale, nweak, weak,
	p1, p2, dfound, unmatched, n2, oldrow, newrow, oldcol, newcol, pp ;
#ifdef COMPLEX
    Int split = SPLIT (Az) ;
#endif
#ifndef NRECIPROCAL
    Int do_recip = FALSE ;
#endif

#ifndef NDEBUG
    /* UMF_debug += 99 ; */
    DEBUGm3 (("\n ==================================UMF_2by2: tol %g\n", tol)) ;
    ASSERT (AMD_valid (n, n, Ap, Ai) == AMD_OK) ;
    for (k = n1 ; k < n - nempty ; k++)
    {
	ASSERT (Cperm1 [k] == Rperm1 [k]) ;
    }
#endif

    /* ---------------------------------------------------------------------- */
    /* determine scaling options */
    /* ---------------------------------------------------------------------- */

    /* use the values, but only if they are present */
    /* ignore the values if tol <= 0 */
    do_values = (tol > 0) && (Ax != (double *) NULL) ;
    if (do_values && (Rs != (double *) NULL))
    {
	do_sum = (scale == UMFPACK_SCALE_SUM) ;
	do_max = (scale == UMFPACK_SCALE_MAX) ;
    }
    else
    {
	/* no scaling */
	do_sum = FALSE ;
	do_max = FALSE ;
    }
    do_scale = do_max || do_sum ;
    DEBUGm3 (("do_values "ID" do_sum "ID" do_max "ID" do_scale "ID"\n",
	do_values, do_sum, do_max, do_scale)) ;

    /* ---------------------------------------------------------------------- */
    /* compute the row scaling, if requested */
    /* ---------------------------------------------------------------------- */

    /* see also umf_kernel_init */

    if (do_scale)
    {
#ifndef NRECIPROCAL
	double rsmin ;
#endif
	for (row = 0 ; row < n ; row++)
	{
	    Rs [row] = 0.0 ;
	}
	for (col = 0 ; col < n ; col++)
	{
	    p2 = Ap [col+1] ;
	    for (p = Ap [col] ; p < p2 ; p++)
	    {
		row = Ai [p] ;
		ASSIGN (aij, Ax, Az, p, split) ;
		APPROX_ABS (value, aij) ;
		rs = Rs [row] ;
		if (!SCALAR_IS_NAN (rs))
		{
		    if (SCALAR_IS_NAN (value))
		    {
			/* if any entry in a row is NaN, then the scale factor
			 * for the row is NaN.  It will be set to 1 later. */
			Rs [row] = value ;
		    }
		    else if (do_max)
		    {
			Rs [row] = MAX (rs, value) ;
		    }
		    else
		    {
			Rs [row] += value ;
		    }
		}
	    }
	}
#ifndef NRECIPROCAL
	rsmin = Rs [0] ;
	if (SCALAR_IS_ZERO (rsmin) || SCALAR_IS_NAN (rsmin))
	{
	    rsmin = 1.0 ;
	}
#endif
	for (row = 0 ; row < n ; row++)
	{
	    /* do not scale an empty row, or a row with a NaN */
	    rs = Rs [row] ;
	    if (SCALAR_IS_ZERO (rs) || SCALAR_IS_NAN (rs))
	    {
		Rs [row] = 1.0 ;
	    }
#ifndef NRECIPROCAL
	    rsmin = MIN (rsmin, Rs [row]) ;
#endif
	}

#ifndef NRECIPROCAL
	/* multiply by the reciprocal if Rs is not too small */
	do_recip = (rsmin >= RECIPROCAL_TOLERANCE) ;
	if (do_recip)
	{
	    /* invert the scale factors */
	    for (row = 0 ; row < n ; row++)
	    {
		Rs [row] = 1.0 / Rs [row] ;
	    }
	}
#endif
    }

    /* ---------------------------------------------------------------------- */
    /* compute the max in each column and find diagonal */
    /* ---------------------------------------------------------------------- */

    nweak = 0 ;

#ifndef NDEBUG
    for (k = 0 ; k < n ; k++)
    {
	ASSERT (Rperm1 [k] >= 0 && Rperm1 [k] < n) ;
	ASSERT (InvRperm1 [Rperm1 [k]] == k) ;
    }
#endif

    n2 = n - n1 - nempty ;

    /* use Ri to count the number of strong entries in each row */
    for (row = 0 ; row < n2 ; row++)
    {
	Ri [row] = 0 ;
    }

    pp = 0 ;
    ctol = 0 ;
    dvalue = 1 ;

    /* construct C = pruned submatrix, strong values only, column form */

    for (k = n1 ; k < n - nempty ; k++)
    {
	oldcol = Cperm1 [k] ;
	newcol = k - n1 ;
	Next [newcol] = EMPTY ;
	DEBUGm1 (("Column "ID" newcol "ID" oldcol "ID"\n", k, newcol, oldcol)) ;

	Cp [newcol] = pp ;

	dfound = FALSE ;
	p1 = Ap [oldcol] ;
	p2 = Ap [oldcol+1] ;
	if (do_values)
	{
	    cmax = 0 ;
	    dvalue = 0 ;

	    if (!do_scale)
	    {
		/* no scaling */
		for (p = p1 ; p < p2 ; p++)
		{
		    oldrow = Ai [p] ;
		    ASSERT (oldrow >= 0 && oldrow < n) ;
		    newrow = InvRperm1 [oldrow] - n1 ;
		    ASSERT (newrow >= -n1 && newrow < n2) ;
		    if (newrow < 0) continue ;
		    ASSIGN (aij, Ax, Az, p, split) ;
		    APPROX_ABS (value, aij) ;
		    /* if either cmax or value is NaN, define cmax as NaN */
		    if (!SCALAR_IS_NAN (cmax))
		    {
			if (SCALAR_IS_NAN (value))
			{
			    cmax = value ;
			}
			else
			{
			    cmax = MAX (cmax, value) ;
			}
		    }
		    if (oldrow == oldcol)
		    {
			/* we found the diagonal entry in this column */
			dvalue = value ;
			dfound = TRUE ;
			ASSERT (newrow == newcol) ;
		    }
		}
	    }
#ifndef NRECIPROCAL
	    else if (do_recip)
	    {
		/* multiply by the reciprocal */
		for (p = p1 ; p < p2 ; p++)
		{
		    oldrow = Ai [p] ;
		    ASSERT (oldrow >= 0 && oldrow < n) ;
		    newrow = InvRperm1 [oldrow] - n1 ;
		    ASSERT (newrow >= -n1 && newrow < n2) ;
		    if (newrow < 0) continue ;
		    ASSIGN (aij, Ax, Az, p, split) ;
		    APPROX_ABS (value, aij) ;
		    value *= Rs [oldrow] ;
		    /* if either cmax or value is NaN, define cmax as NaN */
		    if (!SCALAR_IS_NAN (cmax))
		    {
			if (SCALAR_IS_NAN (value))
			{
			    cmax = value ;
			}
			else
			{
			    cmax = MAX (cmax, value) ;
			}
		    }
		    if (oldrow == oldcol)
		    {
			/* we found the diagonal entry in this column */
			dvalue = value ;
			dfound = TRUE ;
			ASSERT (newrow == newcol) ;
		    }
		}
	    }
#endif
	    else
	    {
		/* divide instead */
		for (p = p1 ; p < p2 ; p++)
		{
		    oldrow = Ai [p] ;
		    ASSERT (oldrow >= 0 && oldrow < n) ;
		    newrow = InvRperm1 [oldrow] - n1 ;
		    ASSERT (newrow >= -n1 && newrow < n2) ;
		    if (newrow < 0) continue ;
		    ASSIGN (aij, Ax, Az, p, split) ;
		    APPROX_ABS (value, aij) ;
		    value /= Rs [oldrow] ;
		    /* if either cmax or value is NaN, define cmax as NaN */
		    if (!SCALAR_IS_NAN (cmax))
		    {
			if (SCALAR_IS_NAN (value))
			{
			    cmax = value ;
			}
			else
			{
			    cmax = MAX (cmax, value) ;
			}
		    }
		    if (oldrow == oldcol)
		    {
			/* we found the diagonal entry in this column */
			dvalue = value ;
			dfound = TRUE ;
			ASSERT (newrow == newcol) ;
		    }
		}
	    }

	    ctol = tol * cmax ;
	    DEBUGm1 (("    cmax col "ID" %g  ctol %g\n", oldcol, cmax, ctol)) ;
	}
	else
	{
	    for (p = p1 ; p < p2 ; p++)
	    {
		oldrow = Ai [p] ;
		ASSERT (oldrow >= 0 && oldrow < n) ;
		newrow = InvRperm1 [oldrow] - n1 ;
		ASSERT (newrow >= -n1 && newrow < n2) ;
		if (newrow < 0) continue ;
		Ci [pp++] = newrow ;
		if (oldrow == oldcol)
		{
		    /* we found the diagonal entry in this column */
		    ASSERT (newrow == newcol) ;
		    dfound = TRUE ;
		}
		/* count the entries in each column */
		Ri [newrow]++ ;
	    }
	}

	/* ------------------------------------------------------------------ */
	/* flag the weak diagonals */
	/* ------------------------------------------------------------------ */

	if (!dfound)
	{
	    /* no diagonal entry present */
	    weak = TRUE ;
	}
	else
	{
	    /* diagonal entry is present, check its value */
	    weak = (do_values) ?  WEAK (dvalue, ctol) : FALSE ;
	}
	if (weak)
	{
	    /* flag this column as weak */
	    DEBUG0 (("Weak!\n")) ;
	    Next [newcol] = IS_WEAK ;
	    nweak++ ;
	}

	/* ------------------------------------------------------------------ */
	/* count entries in each row that are not numerically weak */
	/* ------------------------------------------------------------------ */

	if (do_values)
	{
	    if (!do_scale)
	    {
		/* no scaling */
		for (p = p1 ; p < p2 ; p++)
		{
		    oldrow = Ai [p] ;
		    newrow = InvRperm1 [oldrow] - n1 ;
		    if (newrow < 0) continue ;
		    ASSIGN (aij, Ax, Az, p, split) ;
		    APPROX_ABS (value, aij) ;
		    weak = WEAK (value, ctol) ;
		    if (!weak)
		    {
			DEBUG0 (("    strong: row "ID": %g\n", oldrow, value)) ;
			Ci [pp++] = newrow ;
			Ri [newrow]++ ;
		    }
		}
	    }
#ifndef NRECIPROCAL
	    else if (do_recip)
	    {
		/* multiply by the reciprocal */
		for (p = p1 ; p < p2 ; p++)
		{
		    oldrow = Ai [p] ;
		    newrow = InvRperm1 [oldrow] - n1 ;
		    if (newrow < 0) continue ;
		    ASSIGN (aij, Ax, Az, p, split) ;
		    APPROX_ABS (value, aij) ;
		    value *= Rs [oldrow] ;
		    weak = WEAK (value, ctol) ;
		    if (!weak)
		    {
			DEBUG0 (("    strong: row "ID": %g\n", oldrow, value)) ;
			Ci [pp++] = newrow ;
			Ri [newrow]++ ;
		    }
		}
	    }
#endif
	    else
	    {
		/* divide instead */
		for (p = p1 ; p < p2 ; p++)
		{
		    oldrow = Ai [p] ;
		    newrow = InvRperm1 [oldrow] - n1 ;
		    if (newrow < 0) continue ;
		    ASSIGN (aij, Ax, Az, p, split) ;
		    APPROX_ABS (value, aij) ;
		    value /= Rs [oldrow] ;
		    weak = WEAK (value, ctol) ;
		    if (!weak)
		    {
			DEBUG0 (("    strong: row "ID": %g\n", oldrow, value)) ;
			Ci [pp++] = newrow ;
			Ri [newrow]++ ;
		    }
		}
	    }
	}
    }
    Cp [n2] = pp ;
    ASSERT (AMD_valid (n2, n2, Cp, Ci) == AMD_OK) ;

    if (nweak == 0)
    {
	/* nothing to do, quick return */
	DEBUGm2 (("\n =============================UMF_2by2: quick return\n")) ;
	for (k = 0 ; k < n ; k++)
	{
	    P [k] = k ;
	}
	*p_nweak = 0 ;
	*p_unmatched = 0 ;
	return ;
    }

#ifndef NDEBUG
    for (k = 0 ; k < n2 ; k++)
    {
	P [k] = EMPTY ;
    }
    for (k = 0 ; k < n2 ; k++)
    {
	ASSERT (Degree [k] >= 0 && Degree [k] < n2) ;
    }
#endif

    /* ---------------------------------------------------------------------- */
    /* find the 2-by-2 permutation */
    /* ---------------------------------------------------------------------- */

    /* The matrix S is now mapped to the index range 0 to n2-1.  We have
     * S = A (Rperm [n1 .. n-nempty-1], Cperm [n1 .. n-nempty-1]), and then
     * C = pattern of strong entries in S.  A weak diagonal k in S is marked
     * with Next [k] = IS_WEAK. */

    unmatched = two_by_two (n2, Cp, Ci, Degree, Next, Ri, P, Rp, Head) ;

    /* ---------------------------------------------------------------------- */

    *p_nweak = nweak ;
    *p_unmatched = unmatched ;

#ifndef NDEBUG
    DEBUGm4 (("UMF_2by2: weak "ID"  unmatched "ID"\n", nweak, unmatched)) ;
    for (row = 0 ; row < n ; row++)
    {
	DEBUGm2 (("P ["ID"] = "ID"\n", row, P [row])) ;
    }
    DEBUGm2 (("\n =============================UMF_2by2: done\n\n")) ;
#endif
}
Beispiel #6
0
GLOBAL void AMD_1
(
    Int n,		/* n > 0 */
    const Int Ap [ ],	/* input of size n+1, not modified */
    const Int Ai [ ],	/* input of size nz = Ap [n], not modified */
    Int P [ ],		/* size n output permutation */
    Int Pinv [ ],	/* size n output inverse permutation */
    Int Len [ ],	/* size n input, undefined on output */
    Int slen,		/* slen >= sum (Len [0..n-1]) + 7n,
			 * ideally slen = 1.2 * sum (Len) + 8n */
    Int S [ ],		/* size slen workspace */
    double Control [ ],	/* input array of size AMD_CONTROL */
    double Info [ ]	/* output array of size AMD_INFO */
)
{
    Int i, j, k, p, pfree, iwlen, pj, p1, p2, pj2, *Iw, *Pe, *Nv, *Head,
	*Elen, *Degree, *s, *W, *Sp, *Tp ;

    /* --------------------------------------------------------------------- */
    /* construct the matrix for AMD_2 */
    /* --------------------------------------------------------------------- */

    ASSERT (n > 0) ;

    iwlen = slen - 6*n ;
    s = S ;
    Pe = s ;	    s += n ;
    Nv = s ;	    s += n ;
    Head = s ;	    s += n ;
    Elen = s ;	    s += n ;
    Degree = s ;    s += n ;
    W = s ;	    s += n ;
    Iw = s ;	    s += iwlen ;

    ASSERT (AMD_valid (n, n, Ap, Ai)) ;

    /* construct the pointers for A+A' */
    Sp = Nv ;			/* use Nv and W as workspace for Sp and Tp [ */
    Tp = W ;
    pfree = 0 ;
    for (j = 0 ; j < n ; j++)
    {
	Pe [j] = pfree ;
	Sp [j] = pfree ;
	pfree += Len [j] ;
    }

    /* Note that this restriction on iwlen is slightly more restrictive than
     * what is strictly required in AMD_2.  AMD_2 can operate with no elbow
     * room at all, but it will be very slow.  For better performance, at
     * least size-n elbow room is enforced. */
    ASSERT (iwlen >= pfree + n) ;

#ifndef NDEBUG
    for (p = 0 ; p < iwlen ; p++) Iw [p] = EMPTY ;
#endif

    for (k = 0 ; k < n ; k++)
    {
	AMD_DEBUG1 (("Construct row/column k= "ID" of A+A'\n", k))  ;
	p1 = Ap [k] ;
	p2 = Ap [k+1] ;

	/* construct A+A' */
	for (p = p1 ; p < p2 ; )
	{
	    /* scan the upper triangular part of A */
	    j = Ai [p] ;
	    ASSERT (j >= 0 && j < n) ;
	    if (j < k)
	    {
		/* entry A (j,k) in the strictly upper triangular part */
		ASSERT (Sp [j] < (j == n-1 ? pfree : Pe [j+1])) ;
		ASSERT (Sp [k] < (k == n-1 ? pfree : Pe [k+1])) ;
		Iw [Sp [j]++] = k ;
		Iw [Sp [k]++] = j ;
		p++ ;
	    }
	    else if (j == k)
	    {
		/* skip the diagonal */
		p++ ;
		break ;
	    }
	    else /* j > k */
	    {
		/* first entry below the diagonal */
		break ;
	    }
	    /* scan lower triangular part of A, in column j until reaching
	     * row k.  Start where last scan left off. */
	    ASSERT (Ap [j] <= Tp [j] && Tp [j] <= Ap [j+1]) ;
	    pj2 = Ap [j+1] ;
	    for (pj = Tp [j] ; pj < pj2 ; )
	    {
		i = Ai [pj] ;
		ASSERT (i >= 0 && i < n) ;
		if (i < k)
		{
		    /* A (i,j) is only in the lower part, not in upper */
		    ASSERT (Sp [i] < (i == n-1 ? pfree : Pe [i+1])) ;
		    ASSERT (Sp [j] < (j == n-1 ? pfree : Pe [j+1])) ;
		    Iw [Sp [i]++] = j ;
		    Iw [Sp [j]++] = i ;
		    pj++ ;
		}
		else if (i == k)
		{
		    /* entry A (k,j) in lower part and A (j,k) in upper */
		    pj++ ;
		    break ;
		}
		else /* i > k */
		{
		    /* consider this entry later, when k advances to i */
		    break ;
		}
	    }
	    Tp [j] = pj ;
	}
	Tp [k] = p ;
    }

    /* clean up, for remaining mismatched entries */
    for (j = 0 ; j < n ; j++)
    {
	for (pj = Tp [j] ; pj < Ap [j+1] ; pj++)
	{
	    i = Ai [pj] ;
	    ASSERT (i >= 0 && i < n) ;
	    /* A (i,j) is only in the lower part, not in upper */
	    ASSERT (Sp [i] < (i == n-1 ? pfree : Pe [i+1])) ;
	    ASSERT (Sp [j] < (j == n-1 ? pfree : Pe [j+1])) ;
	    Iw [Sp [i]++] = j ;
	    Iw [Sp [j]++] = i ;
	}
    }

#ifndef NDEBUG
    for (j = 0 ; j < n-1 ; j++) ASSERT (Sp [j] == Pe [j+1]) ;
    ASSERT (Sp [n-1] == pfree) ;
#endif

    /* Tp and Sp no longer needed ] */

    /* --------------------------------------------------------------------- */
    /* order the matrix */
    /* --------------------------------------------------------------------- */

    AMD_2 (n, Pe, Iw, Len, iwlen, pfree,
	Nv, Pinv, P, Head, Elen, Degree, W, Control, Info) ;
}
Beispiel #7
0
GLOBAL Int AMD_order
(
    Int n,
    const Int Ap [ ],
    const Int Ai [ ],
    Int P [ ],
    double Control [ ],
    double Info [ ]
)
{
    Int *Len, *S, nz, i, *Pinv, info, status, *Rp, *Ri, *Cp, *Ci, ok ;
    size_t nzaat, slen ;
    double mem = 0 ;

#ifndef NDEBUG
    AMD_debug_init ("amd") ;
#endif

    /* clear the Info array, if it exists */
    info = Info != (double *) NULL ;
    if (info)
    {
	for (i = 0 ; i < AMD_INFO ; i++)
	{
	    Info [i] = EMPTY ;
	}
	Info [AMD_N] = n ;
	Info [AMD_STATUS] = AMD_OK ;
    }

    /* make sure inputs exist and n is >= 0 */
    if (Ai == (Int *) NULL || Ap == (Int *) NULL || P == (Int *) NULL || n < 0)
    {
	if (info) Info [AMD_STATUS] = AMD_INVALID ;
	return (AMD_INVALID) ;	    /* arguments are invalid */
    }

    if (n == 0)
    {
	return (AMD_OK) ;	    /* n is 0 so there's nothing to do */
    }

    nz = Ap [n] ;
    if (info)
    {
	Info [AMD_NZ] = nz ;
    }
    if (nz < 0)
    {
	if (info) Info [AMD_STATUS] = AMD_INVALID ;
	return (AMD_INVALID) ;
    }

    /* check if n or nz will cause size_t overflow */
    if (((size_t) n) >= SIZE_T_MAX / sizeof (Int)
     || ((size_t) nz) >= SIZE_T_MAX / sizeof (Int))
    {
	if (info) Info [AMD_STATUS] = AMD_OUT_OF_MEMORY ;
	return (AMD_OUT_OF_MEMORY) ;	    /* problem too large */
    }

    /* check the input matrix:	AMD_OK, AMD_INVALID, or AMD_OK_BUT_JUMBLED */
    status = AMD_valid (n, n, Ap, Ai) ;

    if (status == AMD_INVALID)
    {
	if (info) Info [AMD_STATUS] = AMD_INVALID ;
	return (AMD_INVALID) ;	    /* matrix is invalid */
    }

    /* allocate two size-n integer workspaces */
    Len = (Int*)amd_malloc (n * sizeof (Int)) ;
    Pinv = (Int*)amd_malloc (n * sizeof (Int)) ;
    mem += n ;
    mem += n ;
    if (!Len || !Pinv)
    {
	/* :: out of memory :: */
	amd_free (Len) ;
	amd_free (Pinv) ;
	if (info) Info [AMD_STATUS] = AMD_OUT_OF_MEMORY ;
	return (AMD_OUT_OF_MEMORY) ;
    }

    if (status == AMD_OK_BUT_JUMBLED)
    {
	/* sort the input matrix and remove duplicate entries */
	AMD_DEBUG1 (("Matrix is jumbled\n")) ;
	Rp = (Int*)amd_malloc ((n+1) * sizeof (Int)) ;
	Ri = (Int*)amd_malloc (MAX (nz,1) * sizeof (Int)) ;
	mem += (n+1) ;
	mem += MAX (nz,1) ;
	if (!Rp || !Ri)
	{
	    /* :: out of memory :: */
	    amd_free (Rp) ;
	    amd_free (Ri) ;
	    amd_free (Len) ;
	    amd_free (Pinv) ;
	    if (info) Info [AMD_STATUS] = AMD_OUT_OF_MEMORY ;
	    return (AMD_OUT_OF_MEMORY) ;
	}
	/* use Len and Pinv as workspace to create R = A' */
	AMD_preprocess (n, Ap, Ai, Rp, Ri, Len, Pinv) ;
	Cp = Rp ;
	Ci = Ri ;
    }
    else
    {
	/* order the input matrix as-is.  No need to compute R = A' first */
	Rp = NULL ;
	Ri = NULL ;
	Cp = (Int *) Ap ;
	Ci = (Int *) Ai ;
    }

    /* --------------------------------------------------------------------- */
    /* determine the symmetry and count off-diagonal nonzeros in A+A' */
    /* --------------------------------------------------------------------- */

    nzaat = AMD_aat (n, Cp, Ci, Len, P, Info) ;
    AMD_DEBUG1 (("nzaat: %g\n", (double) nzaat)) ;
    ASSERT ((MAX (nz-n, 0) <= nzaat) && (nzaat <= 2 * (size_t) nz)) ;

    /* --------------------------------------------------------------------- */
    /* allocate workspace for matrix, elbow room, and 6 size-n vectors */
    /* --------------------------------------------------------------------- */

    S = NULL ;
    slen = nzaat ;			/* space for matrix */
    ok = ((slen + nzaat/5) >= slen) ;	/* check for size_t overflow */
    slen += nzaat/5 ;			/* add elbow room */
    for (i = 0 ; ok && i < 7 ; i++)
    {
	ok = ((slen + n) > slen) ;	/* check for size_t overflow */
	slen += n ;			/* size-n elbow room, 6 size-n work */
    }
    mem += slen ;
    ok = ok && (slen < SIZE_T_MAX / sizeof (Int)) ; /* check for overflow */
    ok = ok && (slen < Int_MAX) ;	/* S[i] for Int i must be OK */
    if (ok)
    {
	S = (Int*)amd_malloc (slen * sizeof (Int)) ;
    }
    AMD_DEBUG1 (("slen %g\n", (double) slen)) ;
    if (!S)
    {
	/* :: out of memory :: (or problem too large) */
	amd_free (Rp) ;
	amd_free (Ri) ;
	amd_free (Len) ;
	amd_free (Pinv) ;
	if (info) Info [AMD_STATUS] = AMD_OUT_OF_MEMORY ;
	return (AMD_OUT_OF_MEMORY) ;
    }
    if (info)
    {
	/* memory usage, in bytes. */
	Info [AMD_MEMORY] = mem * sizeof (Int) ;
    }

    /* --------------------------------------------------------------------- */
    /* order the matrix */
    /* --------------------------------------------------------------------- */

    AMD_1 (n, Cp, Ci, P, Pinv, Len, slen, S, Control, Info) ;

    /* --------------------------------------------------------------------- */
    /* free the workspace */
    /* --------------------------------------------------------------------- */

    amd_free (Rp) ;
    amd_free (Ri) ;
    amd_free (Len) ;
    amd_free (Pinv) ;
    amd_free (S) ;
    if (info) Info [AMD_STATUS] = status ;
    return (status) ;	    /* successful ordering */
}
Beispiel #8
0
GLOBAL size_t AMD_aat	/* returns nz in A+A' */
(
    Int n,
    const Int Ap [ ],
    const Int Ai [ ],
    Int Len [ ],	/* Len [j]: length of column j of A+A', excl diagonal*/
    Int Tp [ ],		/* workspace of size n */
    double Info [ ]
)
{
    Int p1, p2, p, i, j, pj, pj2, k, nzdiag, nzboth, nz ;
    double sym ;
    size_t nzaat ;

#ifndef NDEBUG
    AMD_debug_init ("AMD AAT") ;
    for (k = 0 ; k < n ; k++) Tp [k] = EMPTY ;
    ASSERT (AMD_valid (n, n, Ap, Ai) == AMD_OK) ;
#endif

    if (Info != (double *) NULL)
    {
	/* clear the Info array, if it exists */
	for (i = 0 ; i < AMD_INFO ; i++)
	{
	    Info [i] = EMPTY ;
	}
	Info [AMD_STATUS] = AMD_OK ;
    }

    for (k = 0 ; k < n ; k++)
    {
	Len [k] = 0 ;
    }

    nzdiag = 0 ;
    nzboth = 0 ;
    nz = Ap [n] ;

    for (k = 0 ; k < n ; k++)
    {
	p1 = Ap [k] ;
	p2 = Ap [k+1] ;
	AMD_DEBUG2 (("\nAAT Column: "ID" p1: "ID" p2: "ID"\n", k, p1, p2)) ;

	/* construct A+A' */
	for (p = p1 ; p < p2 ; )
	{
	    /* scan the upper triangular part of A */
	    j = Ai [p] ;
	    if (j < k)
	    {
		/* entry A (j,k) is in the strictly upper triangular part,
		 * add both A (j,k) and A (k,j) to the matrix A+A' */
		Len [j]++ ;
		Len [k]++ ;
		AMD_DEBUG3 (("    upper ("ID","ID") ("ID","ID")\n", j,k, k,j));
		p++ ;
	    }
	    else if (j == k)
	    {
		/* skip the diagonal */
		p++ ;
		nzdiag++ ;
		break ;
	    }
	    else /* j > k */
	    {
		/* first entry below the diagonal */
		break ;
	    }
	    /* scan lower triangular part of A, in column j until reaching
	     * row k.  Start where last scan left off. */
	    ASSERT (Tp [j] != EMPTY) ;
	    ASSERT (Ap [j] <= Tp [j] && Tp [j] <= Ap [j+1]) ;
	    pj2 = Ap [j+1] ;
	    for (pj = Tp [j] ; pj < pj2 ; )
	    {
		i = Ai [pj] ;
		if (i < k)
		{
		    /* A (i,j) is only in the lower part, not in upper.
		     * add both A (i,j) and A (j,i) to the matrix A+A' */
		    Len [i]++ ;
		    Len [j]++ ;
		    AMD_DEBUG3 (("    lower ("ID","ID") ("ID","ID")\n",
			i,j, j,i)) ;
		    pj++ ;
		}
		else if (i == k)
		{
		    /* entry A (k,j) in lower part and A (j,k) in upper */
		    pj++ ;
		    nzboth++ ;
		    break ;
		}
		else /* i > k */
		{
		    /* consider this entry later, when k advances to i */
		    break ;
		}
	    }
	    Tp [j] = pj ;
	}
	/* Tp [k] points to the entry just below the diagonal in column k */
	Tp [k] = p ;
    }

    /* clean up, for remaining mismatched entries */
    for (j = 0 ; j < n ; j++)
    {
	for (pj = Tp [j] ; pj < Ap [j+1] ; pj++)
	{
	    i = Ai [pj] ;
	    /* A (i,j) is only in the lower part, not in upper.
	     * add both A (i,j) and A (j,i) to the matrix A+A' */
	    Len [i]++ ;
	    Len [j]++ ;
	    AMD_DEBUG3 (("    lower cleanup ("ID","ID") ("ID","ID")\n",
		i,j, j,i)) ;
	}
    }

    /* --------------------------------------------------------------------- */
    /* compute the symmetry of the nonzero pattern of A */
    /* --------------------------------------------------------------------- */

    /* Given a matrix A, the symmetry of A is:
     *	B = tril (spones (A), -1) + triu (spones (A), 1) ;
     *  sym = nnz (B & B') / nnz (B) ;
     *  or 1 if nnz (B) is zero.
     */

    if (nz == nzdiag)
    {
	sym = 1 ;
    }
    else
    {
	sym = (2 * (double) nzboth) / ((double) (nz - nzdiag)) ;
    }

    nzaat = 0 ;
    for (k = 0 ; k < n ; k++)
    {
	nzaat += Len [k] ;
    }

    AMD_DEBUG1 (("AMD nz in A+A', excluding diagonal (nzaat) = %g\n",
	(double) nzaat)) ;
    AMD_DEBUG1 (("   nzboth: "ID" nz: "ID" nzdiag: "ID" symmetry: %g\n",
		nzboth, nz, nzdiag, sym)) ;

    if (Info != (double *) NULL)
    {
	Info [AMD_STATUS] = AMD_OK ;
	Info [AMD_N] = n ;
	Info [AMD_NZ] = nz ;
	Info [AMD_SYMMETRY] = sym ;	    /* symmetry of pattern of A */
	Info [AMD_NZDIAG] = nzdiag ;	    /* nonzeros on diagonal of A */
	Info [AMD_NZ_A_PLUS_AT] = nzaat ;   /* nonzeros in A+A' */
    }

    return (nzaat) ;
}
Beispiel #9
0
GLOBAL Int UMF_transpose
(
    Int n_row,			/* A is n_row-by-n_col */
    Int n_col,
    const Int Ap [ ],		/* size n_col+1 */
    const Int Ai [ ],		/* size nz = Ap [n_col] */
    const double Ax [ ],	/* size nz if present */

    const Int P [ ],	/* P [k] = i means original row i is kth row in A(P,Q)*/
			/* P is identity if not present */
			/* size n_row, if present */

    const Int Q [ ],	/* Q [k] = j means original col j is kth col in A(P,Q)*/
			/* Q is identity if not present */
			/* size nq, if present */
    Int nq,		/* size of Q, ignored if Q is (Int *) NULL */

			/* output matrix: Rp, Ri, Rx, and Rz: */
    Int Rp [ ],		/* size n_row+1 */
    Int Ri [ ],		/* size nz */
    double Rx [ ],	/* size nz, if present */

    Int W [ ],		/* size max (n_row,n_col) workspace */

    Int check		/* if true, then check inputs */
#ifdef COMPLEX
    , const double Az [ ]	/* size nz */
    , double Rz [ ]		/* size nz */
    , Int do_conjugate		/* if true, then do conjugate transpose */
				/* otherwise, do array transpose */
#endif
)
{

    /* ---------------------------------------------------------------------- */
    /* local variables */
    /* ---------------------------------------------------------------------- */

    Int i, j, k, p, bp, newj, do_values ;
#ifdef COMPLEX
    Int split ;
#endif

    /* ---------------------------------------------------------------------- */
    /* check inputs */
    /* ---------------------------------------------------------------------- */

#ifndef NDEBUG
    Int nz ;
    ASSERT (n_col >= 0) ;
    nz = (Ap != (Int *) NULL) ? Ap [n_col] : 0 ;
    DEBUG2 (("UMF_transpose: "ID"-by-"ID" nz "ID"\n", n_row, n_col, nz)) ;
#endif

    if (check)
    {
	/* UMFPACK_symbolic skips this check */
	/* UMFPACK_transpose always does this check */
	if (!Ai || !Ap || !Ri || !Rp || !W)
	{
	    return (UMFPACK_ERROR_argument_missing) ;
	}
	if (n_row <= 0 || n_col <= 0)		/* n_row,n_col must be > 0 */
	{
	    return (UMFPACK_ERROR_n_nonpositive) ;
	}
	if (!UMF_is_permutation (P, W, n_row, n_row) ||
	    !UMF_is_permutation (Q, W, nq, nq))
	{
	    return (UMFPACK_ERROR_invalid_permutation) ;
	}
	if (!AMD_valid (n_row, n_col, Ap, Ai))
	{
	    return (UMFPACK_ERROR_invalid_matrix) ;
	}
    }

#ifndef NDEBUG
    DEBUG2 (("UMF_transpose, input matrix:\n")) ;
    UMF_dump_col_matrix (Ax,
#ifdef COMPLEX
	Az,
#endif
	Ai, Ap, n_row, n_col, nz) ;
#endif

    /* ---------------------------------------------------------------------- */
    /* count the entries in each row of A */
    /* ---------------------------------------------------------------------- */

    /* use W as workspace for RowCount */

    for (i = 0 ; i < n_row ; i++)
    {
	W [i] = 0 ;
	Rp [i] = 0 ;
    }

    if (Q != (Int *) NULL)
    {
	for (newj = 0 ; newj < nq ; newj++)
	{
	    j = Q [newj] ;
	    ASSERT (j >= 0 && j < n_col) ;
	    for (p = Ap [j] ; p < Ap [j+1] ; p++)
	    {
		i = Ai [p] ;
		ASSERT (i >= 0 && i < n_row) ;
		W [i]++ ;
	    }
	}
    }
    else
    {
	for (j = 0 ; j < n_col ; j++)
	{
	    for (p = Ap [j] ; p < Ap [j+1] ; p++)
	    {
		i = Ai [p] ;
		ASSERT (i >= 0 && i < n_row) ;
		W [i]++ ;
	    }
	}
    }

    /* ---------------------------------------------------------------------- */
    /* compute the row pointers for R = A (P,Q) */
    /* ---------------------------------------------------------------------- */

    if (P != (Int *) NULL)
    {
	Rp [0] = 0 ;
	for (k = 0 ; k < n_row ; k++)
	{
	    i = P [k] ;
	    ASSERT (i >= 0 && i < n_row) ;
	    Rp [k+1] = Rp [k] + W [i] ;
	}
	for (k = 0 ; k < n_row ; k++)
	{
	    i = P [k] ;
	    ASSERT (i >= 0 && i < n_row) ;
	    W [i] = Rp [k] ;
	}
    }
    else
    {
	Rp [0] = 0 ;
	for (i = 0 ; i < n_row ; i++)
	{
	    Rp [i+1] = Rp [i] + W [i] ;
	}
	for (i = 0 ; i < n_row ; i++)
	{
	    W [i] = Rp [i] ;
	}
    }
    ASSERT (Rp [n_row] <= Ap [n_col]) ;

    /* at this point, W holds the permuted row pointers */

    /* ---------------------------------------------------------------------- */
    /* construct the row form of B */
    /* ---------------------------------------------------------------------- */

    do_values = Ax && Rx ;

#ifdef COMPLEX
    split = SPLIT (Az) && SPLIT (Rz) ;

    if (do_conjugate && do_values)
    {
	if (Q != (Int *) NULL)
	{
	    if (split)
	    {
		/* R = A (P,Q)' */
		for (newj = 0 ; newj < nq ; newj++)
		{
		    j = Q [newj] ;
		    ASSERT (j >= 0 && j < n_col) ;
		    for (p = Ap [j] ; p < Ap [j+1] ; p++)
		    {
			bp = W [Ai [p]]++ ;
			Ri [bp] = newj ;
			Rx [bp] = Ax [p] ;
			Rz [bp] = -Az [p] ;
		    }
		}
	    }
	    else
	    {
		/* R = A (P,Q)' (merged complex values) */
		for (newj = 0 ; newj < nq ; newj++)
		{
		    j = Q [newj] ;
		    ASSERT (j >= 0 && j < n_col) ;
		    for (p = Ap [j] ; p < Ap [j+1] ; p++)
		    {
			bp = W [Ai [p]]++ ;
			Ri [bp] = newj ;
			Rx [2*bp] = Ax [2*p] ;
			Rx [2*bp+1] = -Ax [2*p+1] ;
		    }
		}
	    }
	}
	else
	{
	    if (split)
	    {
		/* R = A (P,:)' */
		for (j = 0 ; j < n_col ; j++)
		{
		    for (p = Ap [j] ; p < Ap [j+1] ; p++)
		    {
			bp = W [Ai [p]]++ ;
			Ri [bp] = j ;
			Rx [bp] = Ax [p] ;
			Rz [bp] = -Az [p] ;
		    }
		}
	    }
	    else
	    {
		/* R = A (P,:)' (merged complex values) */
		for (j = 0 ; j < n_col ; j++)
		{
		    for (p = Ap [j] ; p < Ap [j+1] ; p++)
		    {
			bp = W [Ai [p]]++ ;
			Ri [bp] = j ;
			Rx [2*bp] = Ax [2*p] ;
			Rx [2*bp+1] = -Ax [2*p+1] ;
		    }
		}
	    }
	}
    }
    else
#endif
    {
	if (Q != (Int *) NULL)
	{
	    if (do_values)
	    {
#ifdef COMPLEX
		if (split)
#endif
		{
		    /* R = A (P,Q).' */
		    for (newj = 0 ; newj < nq ; newj++)
		    {
			j = Q [newj] ;
			ASSERT (j >= 0 && j < n_col) ;
			for (p = Ap [j] ; p < Ap [j+1] ; p++)
			{
			    bp = W [Ai [p]]++ ;
			    Ri [bp] = newj ;
			    Rx [bp] = Ax [p] ;
#ifdef COMPLEX
			    Rz [bp] = Az [p] ;
#endif
			}
		    }
		}
#ifdef COMPLEX
		else
		{
		    /* R = A (P,Q).' (merged complex values) */
		    for (newj = 0 ; newj < nq ; newj++)
		    {
			j = Q [newj] ;
			ASSERT (j >= 0 && j < n_col) ;
			for (p = Ap [j] ; p < Ap [j+1] ; p++)
			{
			    bp = W [Ai [p]]++ ;
			    Ri [bp] = newj ;
			    Rx [2*bp] = Ax [2*p] ;
			    Rx [2*bp+1] = Ax [2*p+1] ;
			}
		    }
		}
#endif
	    }
	    else
	    {
		/* R = pattern of A (P,Q).' */
		for (newj = 0 ; newj < nq ; newj++)
		{
		    j = Q [newj] ;
		    ASSERT (j >= 0 && j < n_col) ;
		    for (p = Ap [j] ; p < Ap [j+1] ; p++)
		    {
			Ri [W [Ai [p]]++] = newj ;
		    }
		}
	    }
	}
	else
	{
	    if (do_values)
	    {
#ifdef COMPLEX
		if (split)
#endif
		{
		    /* R = A (P,:).' */
		    for (j = 0 ; j < n_col ; j++)
		    {
			for (p = Ap [j] ; p < Ap [j+1] ; p++)
			{
			    bp = W [Ai [p]]++ ;
			    Ri [bp] = j ;
			    Rx [bp] = Ax [p] ;
#ifdef COMPLEX
			    Rz [bp] = Az [p] ;
#endif
			}
		    }
		}
#ifdef COMPLEX
		else
		{
		    /* R = A (P,:).' (merged complex values) */
		    for (j = 0 ; j < n_col ; j++)
		    {
			for (p = Ap [j] ; p < Ap [j+1] ; p++)
			{
			    bp = W [Ai [p]]++ ;
			    Ri [bp] = j ;
			    Rx [2*bp] = Ax [2*p] ;
			    Rx [2*bp+1] = Ax [2*p+1] ;
			}
		    }
		}
#endif
	    }
	    else
	    {
		/* R = pattern of A (P,:).' */
		for (j = 0 ; j < n_col ; j++)
		{
		    for (p = Ap [j] ; p < Ap [j+1] ; p++)
		    {
			Ri [W [Ai [p]]++] = j ;
		    }
		}
	    }
	}
    }

#ifndef NDEBUG
    for (k = 0 ; k < n_row ; k++)
    {
	if (P != (Int *) NULL)
	{
	    i = P [k] ;
	}
	else
	{
	    i = k ;
	}
	DEBUG3 ((ID":  W[i] "ID" Rp[k+1] "ID"\n", i, W [i], Rp [k+1])) ;
	ASSERT (W [i] == Rp [k+1]) ;
    }
    DEBUG2 (("UMF_transpose, output matrix:\n")) ;
    UMF_dump_col_matrix (Rx,
#ifdef COMPLEX
	Rz,
#endif
	Ri, Rp, n_col, n_row, Rp [n_row]) ;
    ASSERT (AMD_valid (n_col, n_row, Rp, Ri)) ;
#endif

    return (UMFPACK_OK) ;
}