inline
 int triplet_to_col (int n_row, int n_col, int nz,
                     int const* Ti, int const* Tj,
                     traits::complex_d const* Tx,
                     int* Ap, int* Ai, traits::complex_d* Ax,
                     int* Map)
 {
   assert (Tx == 0 && Ax == 0 || Tx != 0 && Ax != 0);
   double *Txr = 0, *Txi = 0;
   if (Tx != 0) {
     bindings::detail::array<double> ATxr (nz);
     if (!ATxr.valid()) return UMFPACK_ERROR_out_of_memory;
     bindings::detail::array<double> ATxi (nz);
     if (!ATxi.valid()) return UMFPACK_ERROR_out_of_memory;
     Txr = ATxr.storage();
     Txi = ATxi.storage();
     traits::detail::disentangle (Tx, Tx+nz, Txr, Txi);
   }
   double *Axr = 0, *Axi = 0;
   if (Ax != 0) {
     bindings::detail::array<double> AAxr (nz);
     if (!AAxr.valid()) return UMFPACK_ERROR_out_of_memory;
     bindings::detail::array<double> AAxi (nz);
     if (!AAxi.valid()) return UMFPACK_ERROR_out_of_memory;
     Axr = AAxr.storage();
     Axi = AAxi.storage();
   }
   int status;
   status = umfpack_zi_triplet_to_col (n_row, n_col, nz,
                                       Ti, Tj, Txr, Txi,
                                       Ap, Ai, Axr, Axi, Map);
   if (Ax != 0) {
     if (status != UMFPACK_OK) return status;
     traits::detail::interlace (Axr, Axr + nz, Axi, Ax);
   }
   return status;
 }
Example #2
0
void forward_shot_SH(struct waveAC *waveAC, struct PML_AC *PML_AC, struct matSH *matSH, float ** srcpos, int nshots, int ** recpos, int ntr, int nstage, int nfreq){

	/* declaration of global variables */
        extern int NSHOT1, NSHOT2, NONZERO, NX, NY, NXNY, NF;
        extern int SNAP, SEISMO, MYID, INFO, N_STREAMER, READ_REC;
        extern float DH;
        extern char SNAP_FILE[STRING_SIZE];
	extern FILE * FP;
    
        /* declaration of local variables */
        int ishot, status, nxsrc, nysrc, i;
    	double *null = (double *) NULL ;

	int     *Ap, *Ai;
	double  *Ax, *Az, *xr, *xi; 
	double  time1, time2;
        char filename[STRING_SIZE];
        void *Symbolic, *Numeric;

	/* Allocate memory for compressed sparse column form and solution vector */
	Ap = malloc(sizeof(int)*(NXNY+1));
	Ai = malloc(sizeof(int)*NONZERO);
	Ax = malloc(sizeof(double)*NONZERO);
	Az = malloc(sizeof(double)*NONZERO);
	xr = malloc(sizeof(double)*NONZERO);
	xi = malloc(sizeof(double)*NONZERO);

        /* assemble acoustic impedance matrix */
        init_A_SH_9p_pml(PML_AC,matSH,waveAC);

        /* convert triplet to compressed sparse column format */
        status = umfpack_zi_triplet_to_col(NXNY,NXNY,NONZERO,(*waveAC).irow,(*waveAC).icol,(*waveAC).Ar,(*waveAC).Ai,Ap,Ai,Ax,Az,NULL);

	/* Here is something buggy (*waveAC).Ar != Ax and (*waveAC).Ai != Az.
           Therefore, set  Ax = (*waveAC).Ar and Az = (*waveAC).Ai */
	for (i=0;i<NONZERO;i++){
	     Ax[i] = (*waveAC).Ar[i];
	     Az[i] = (*waveAC).Ai[i];
        }

	if((MYID==0)&&(INFO==1)){
	  printf("\n==================================== \n");
	  printf("\n *****  LU factorization **********  \n");
	  printf("\n==================================== \n\n");
	  time1=MPI_Wtime(); 
	}

        /* symbolic factorization */
	status = umfpack_zi_symbolic(NXNY, NXNY, Ap, Ai, Ax, Az, &Symbolic, null, null);

        /* sparse LU decomposition */
	status = umfpack_zi_numeric(Ap, Ai, Ax, Az, Symbolic, &Numeric, null, null);
        umfpack_zi_free_symbolic (&Symbolic);

	if((MYID==0)&&(INFO==1)){
	  time2=MPI_Wtime();
	  printf("\n Finished after %4.2f s \n",time2-time1);
	}

	if((MYID==0)&&(INFO==1)){
	  printf("\n============================================================================================================= \n");
	  printf("\n *****  Solve elastic SH forward problem by FDFD for shot %d - %d (f = %3.2f Hz) on MPI process no. %d **********  \n",NSHOT1,NSHOT2-1,(*waveAC).freq, MYID);
	  printf("\n============================================================================================================= \n\n");				
	  time1=MPI_Wtime(); 
	}

        /* loop over all shots */
	for (ishot=NSHOT1;ishot<NSHOT2;ishot++){

		/* read receiver positions from receiver files for each shot */
		if(READ_REC==1){
		    acq.recpos=receiver(FP, &ntr, 1);			                         
      		}

                /* define source vector RHS */
                RHS_source_AC(waveAC,srcpos,ishot);

                /* solve forward problem by forward and back substitution */
    		status = umfpack_zi_solve(UMFPACK_A, Ap, Ai, Ax, Az, xr, xi, (*waveAC).RHSr, (*waveAC).RHSi, Numeric, null, null);

		/* convert vector xr/xi to pr/pi */
		vec2mat((*waveAC).pr,(*waveAC).pi,xr,xi);

		/* write real part of pressure wavefield to file */
		if(SNAP==1){
		   sprintf(filename,"%s_shot_%d.p",SNAP_FILE,ishot);
		   /* writemod(filename,(*waveAC).pr,3); */
		   writemod_true(filename,(*waveAC).pr,3);
		}

		/* write FD seismogram files */
		if(SEISMO==1){		   
		   calc_seis_AC(waveAC,acq.recpos,ntr,ishot,nshots,nfreq);
		}

		if(READ_REC==1){
		   free_imatrix(acq.recpos,1,3,1,ntr);
		   ntr=0;
 		}

	}

	if((MYID==0)&&(INFO==1)){
	  time2=MPI_Wtime();
	  printf("\n Finished after %4.2f s \n",time2-time1);
	}
         	    
	/* free memory */
    	free(Ap); free(Ai); free(Ax); free(Az); free(xr); free(xi); 

	umfpack_zi_free_numeric (&Numeric);	

}
Example #3
0
int main (int argc, char **argv)
{
    double Info [UMFPACK_INFO], Control [UMFPACK_CONTROL], *Ax, *Cx, *Lx, *Ux,
	*W, t [2], *Dx, rnorm, *Rb, *y, *Rs ;
    double *Az, *Lz, *Uz, *Dz, *Cz, *Rbz, *yz ;
    int *Ap, *Ai, *Cp, *Ci, row, col, p, lnz, unz, nr, nc, *Lp, *Li, *Ui, *Up,
	*P, *Q, *Lj, i, j, k, anz, nfr, nchains, *Qinit, fnpiv, lnz1, unz1, nz1,
	status, *Front_npivcol, *Front_parent, *Chain_start, *Wi, *Pinit, n1,
	*Chain_maxrows, *Chain_maxcols, *Front_1strow, *Front_leftmostdesc,
	nzud, do_recip ;
    void *Symbolic, *Numeric ;

    /* ---------------------------------------------------------------------- */
    /* initializations */
    /* ---------------------------------------------------------------------- */

    umfpack_tic (t) ;

    printf ("\nUMFPACK V%d.%d (%s) demo: _zi_ version\n",
	    UMFPACK_MAIN_VERSION, UMFPACK_SUB_VERSION, UMFPACK_DATE) ;

    /* get the default control parameters */
    umfpack_zi_defaults (Control) ;

    /* change the default print level for this demo */
    /* (otherwise, nothing will print) */
    Control [UMFPACK_PRL] = 6 ;

    /* print the license agreement */
    umfpack_zi_report_status (Control, UMFPACK_OK) ;
    Control [UMFPACK_PRL] = 5 ;

    /* print the control parameters */
    umfpack_zi_report_control (Control) ;

    /* ---------------------------------------------------------------------- */
    /* print A and b, and convert A to column-form */
    /* ---------------------------------------------------------------------- */

    /* print the right-hand-side */
    printf ("\nb: ") ;
    (void) umfpack_zi_report_vector (n, b, bz, Control) ;

    /* print the triplet form of the matrix */
    printf ("\nA: ") ;
    (void) umfpack_zi_report_triplet (n, n, nz, Arow, Acol, Aval, Avalz,
	Control) ;

    /* convert to column form */
    nz1 = MAX (nz,1) ;	/* ensure arrays are not of size zero. */
    Ap = (int *) malloc ((n+1) * sizeof (int)) ;
    Ai = (int *) malloc (nz1 * sizeof (int)) ;
    Ax = (double *) malloc (nz1 * sizeof (double)) ;
    Az = (double *) malloc (nz1 * sizeof (double)) ;
    if (!Ap || !Ai || !Ax || !Az)
    {
	error ("out of memory") ;
    }

    status = umfpack_zi_triplet_to_col (n, n, nz, Arow, Acol, Aval, Avalz,
	Ap, Ai, Ax, Az, (int *) NULL) ;

    if (status < 0)
    {
	umfpack_zi_report_status (Control, status) ;
	error ("umfpack_zi_triplet_to_col failed") ;
    }

    /* print the column-form of A */
    printf ("\nA: ") ;
    (void) umfpack_zi_report_matrix (n, n, Ap, Ai, Ax, Az, 1, Control) ;

    /* ---------------------------------------------------------------------- */
    /* symbolic factorization */
    /* ---------------------------------------------------------------------- */

    status = umfpack_zi_symbolic (n, n, Ap, Ai, Ax, Az, &Symbolic,
	Control, Info) ;
    if (status < 0)
    {
	umfpack_zi_report_info (Control, Info) ;
	umfpack_zi_report_status (Control, status) ;
	error ("umfpack_zi_symbolic failed") ;
    }

    /* print the symbolic factorization */

    printf ("\nSymbolic factorization of A: ") ;
    (void) umfpack_zi_report_symbolic (Symbolic, Control) ;

    /* ---------------------------------------------------------------------- */
    /* numeric factorization */
    /* ---------------------------------------------------------------------- */

    status = umfpack_zi_numeric (Ap, Ai, Ax, Az, Symbolic, &Numeric,
	Control, Info) ;
    if (status < 0)
    {
	umfpack_zi_report_info (Control, Info) ;
	umfpack_zi_report_status (Control, status) ;
	error ("umfpack_zi_numeric failed") ;
    }

    /* print the numeric factorization */
    printf ("\nNumeric factorization of A: ") ;
    (void) umfpack_zi_report_numeric (Numeric, Control) ;

    /* ---------------------------------------------------------------------- */
    /* solve Ax=b */
    /* ---------------------------------------------------------------------- */

    status = umfpack_zi_solve (UMFPACK_A, Ap, Ai, Ax, Az, x, xz, b, bz,
	Numeric, Control, Info) ;
    umfpack_zi_report_info (Control, Info) ;
    umfpack_zi_report_status (Control, status) ;
    if (status < 0)
    {
	error ("umfpack_zi_solve failed") ;
    }
    printf ("\nx (solution of Ax=b): ") ;
    (void) umfpack_zi_report_vector (n, x, xz, Control) ;
    rnorm = resid (FALSE, Ap, Ai, Ax, Az) ;
    printf ("maxnorm of residual: %g\n\n", rnorm) ;

    /* ---------------------------------------------------------------------- */
    /* compute the determinant */
    /* ---------------------------------------------------------------------- */

    status = umfpack_zi_get_determinant (x, xz, r, Numeric, Info) ;
    umfpack_zi_report_status (Control, status) ;
    if (status < 0)
    {
	error ("umfpack_zi_get_determinant failed") ;
    }
    printf ("determinant: (%g", x [0]) ;
    printf ("+ (%g)i", xz [0]) ; /* complex */
    printf (") * 10^(%g)\n", r [0]) ;

    /* ---------------------------------------------------------------------- */
    /* solve Ax=b, broken down into steps */
    /* ---------------------------------------------------------------------- */

    /* Rb = R*b */
    Rb  = (double *) malloc (n * sizeof (double)) ;
    Rbz = (double *) malloc (n * sizeof (double)) ;
    y   = (double *) malloc (n * sizeof (double)) ;
    yz  = (double *) malloc (n * sizeof (double)) ;
    if (!Rb || !y) error ("out of memory") ;
    if (!Rbz || !yz) error ("out of memory") ;

    status = umfpack_zi_scale (Rb, Rbz, b, bz, Numeric) ;
    if (status < 0) error ("umfpack_zi_scale failed") ;
    /* solve Ly = P*(Rb) */
    status = umfpack_zi_solve (UMFPACK_Pt_L, Ap, Ai, Ax, Az, y, yz, Rb, Rbz,
	Numeric, Control, Info) ;
    if (status < 0) error ("umfpack_zi_solve failed") ;
    /* solve UQ'x=y */
    status = umfpack_zi_solve (UMFPACK_U_Qt, Ap, Ai, Ax, Az, x, xz, y, yz,
	Numeric, Control, Info) ;
    if (status < 0) error ("umfpack_zi_solve failed") ;
    printf ("\nx (solution of Ax=b, solve is split into 3 steps): ") ;
    (void) umfpack_zi_report_vector (n, x, xz, Control) ;
    rnorm = resid (FALSE, Ap, Ai, Ax, Az) ;
    printf ("maxnorm of residual: %g\n\n", rnorm) ;

    free (Rb) ;
    free (Rbz) ;
    free (y) ;
    free (yz) ;

    /* ---------------------------------------------------------------------- */
    /* solve A'x=b */
    /* ---------------------------------------------------------------------- */

    /* note that this is the complex conjugate transpose, A' */
    status = umfpack_zi_solve (UMFPACK_At, Ap, Ai, Ax, Az, x, xz, b, bz,
	Numeric, Control, Info) ;
    umfpack_zi_report_info (Control, Info) ;
    if (status < 0)
    {
	error ("umfpack_zi_solve failed") ;
    }
    printf ("\nx (solution of A'x=b): ") ;
    (void) umfpack_zi_report_vector (n, x, xz, Control) ;
    rnorm = resid (TRUE, Ap, Ai, Ax, Az) ;
    printf ("maxnorm of residual: %g\n\n", rnorm) ;

    /* ---------------------------------------------------------------------- */
    /* modify one numerical value in the column-form of A */
    /* ---------------------------------------------------------------------- */

    /* change A (1,4), look for row index 1 in column 4. */
    row = 1 ;
    col = 4 ;
    for (p = Ap [col] ; p < Ap [col+1] ; p++)
    {
	if (row == Ai [p])
	{
	    printf ("\nchanging A (%d,%d) to zero\n", row, col) ;
	    Ax [p] = 0.0 ;
	    Az [p] = 0.0 ;
	    break ;
	}
    }
    printf ("\nmodified A: ") ;
    (void) umfpack_zi_report_matrix (n, n, Ap, Ai, Ax, Az, 1, Control) ;

    /* ---------------------------------------------------------------------- */
    /* redo the numeric factorization */
    /* ---------------------------------------------------------------------- */

    /* The pattern (Ap and Ai) hasn't changed, so the symbolic factorization */
    /* doesn't have to be redone, no matter how much we change Ax. */

    /* We don't need the Numeric object any more, so free it. */
    umfpack_zi_free_numeric (&Numeric) ;

    /* Note that a memory leak would have occurred if the old Numeric */
    /* had not been free'd with umfpack_zi_free_numeric above. */
    status = umfpack_zi_numeric (Ap, Ai, Ax, Az, Symbolic, &Numeric,
	Control, Info) ;
    if (status < 0)
    {
	umfpack_zi_report_info (Control, Info) ;
	umfpack_zi_report_status (Control, status) ;
	error ("umfpack_zi_numeric failed") ;
    }
    printf ("\nNumeric factorization of modified A: ") ;
    (void) umfpack_zi_report_numeric (Numeric, Control) ;

    /* ---------------------------------------------------------------------- */
    /* solve Ax=b, with the modified A */
    /* ---------------------------------------------------------------------- */

    status = umfpack_zi_solve (UMFPACK_A, Ap, Ai, Ax, Az, x, xz, b, bz,
	Numeric, Control, Info) ;
    umfpack_zi_report_info (Control, Info) ;
    if (status < 0)
    {
	umfpack_zi_report_status (Control, status) ;
	error ("umfpack_zi_solve failed") ;
    }
    printf ("\nx (with modified A): ") ;
    (void) umfpack_zi_report_vector (n, x, xz, Control) ;
    rnorm = resid (FALSE, Ap, Ai, Ax, Az) ;
    printf ("maxnorm of residual: %g\n\n", rnorm) ;

    /* ---------------------------------------------------------------------- */
    /* modify all of the numerical values of A, but not the pattern */
    /* ---------------------------------------------------------------------- */

    for (col = 0 ; col < n ; col++)
    {
	for (p = Ap [col] ; p < Ap [col+1] ; p++)
	{
	    row = Ai [p] ;
	    printf ("changing ") ;
	    /* complex: */ printf ("real part of ") ;
	    printf ("A (%d,%d) from %g", row, col, Ax [p]) ;
	    Ax [p] = Ax [p] + col*10 - row ;
	    printf (" to %g\n", Ax [p]) ;
	}
    }
    printf ("\ncompletely modified A (same pattern): ") ;
    (void) umfpack_zi_report_matrix (n, n, Ap, Ai, Ax, Az, 1, Control) ;

    /* ---------------------------------------------------------------------- */
    /* save the Symbolic object to file, free it, and load it back in */
    /* ---------------------------------------------------------------------- */

    /* use the default filename, "symbolic.umf" */
    printf ("\nSaving symbolic object:\n") ;
    status = umfpack_zi_save_symbolic (Symbolic, (char *) NULL) ;
    if (status < 0)
    {
	umfpack_zi_report_status (Control, status) ;
	error ("umfpack_zi_save_symbolic failed") ;
    }
    printf ("\nFreeing symbolic object:\n") ;
    umfpack_zi_free_symbolic (&Symbolic) ;
    printf ("\nLoading symbolic object:\n") ;
    status = umfpack_zi_load_symbolic (&Symbolic, (char *) NULL) ;
    if (status < 0)
    {
	umfpack_zi_report_status (Control, status) ;
	error ("umfpack_zi_load_symbolic failed") ;
    }
    printf ("\nDone loading symbolic object\n") ;

    /* ---------------------------------------------------------------------- */
    /* redo the numeric factorization */
    /* ---------------------------------------------------------------------- */

    umfpack_zi_free_numeric (&Numeric) ;
    status = umfpack_zi_numeric (Ap, Ai, Ax, Az, Symbolic, &Numeric,
	Control, Info) ;
    if (status < 0)
    {
	umfpack_zi_report_info (Control, Info) ;
	umfpack_zi_report_status (Control, status) ;
	error ("umfpack_zi_numeric failed") ;
    }
    printf ("\nNumeric factorization of completely modified A: ") ;
    (void) umfpack_zi_report_numeric (Numeric, Control) ;

    /* ---------------------------------------------------------------------- */
    /* solve Ax=b, with the modified A */
    /* ---------------------------------------------------------------------- */

    status = umfpack_zi_solve (UMFPACK_A, Ap, Ai, Ax, Az, x, xz, b, bz,
	Numeric, Control, Info) ;
    umfpack_zi_report_info (Control, Info) ;
    if (status < 0)
    {
	umfpack_zi_report_status (Control, status) ;
	error ("umfpack_zi_solve failed") ;
    }
    printf ("\nx (with completely modified A): ") ;
    (void) umfpack_zi_report_vector (n, x, xz, Control) ;
    rnorm = resid (FALSE, Ap, Ai, Ax, Az) ;
    printf ("maxnorm of residual: %g\n\n", rnorm) ;

    /* ---------------------------------------------------------------------- */
    /* free the symbolic and numeric factorization */
    /* ---------------------------------------------------------------------- */

    umfpack_zi_free_symbolic (&Symbolic) ;
    umfpack_zi_free_numeric (&Numeric) ;

    /* ---------------------------------------------------------------------- */
    /* C = transpose of A */
    /* ---------------------------------------------------------------------- */

    Cp = (int *) malloc ((n+1) * sizeof (int)) ;
    Ci = (int *) malloc (nz1 * sizeof (int)) ;
    Cx = (double *) malloc (nz1 * sizeof (double)) ;
    Cz = (double *) malloc (nz1 * sizeof (double)) ;
    if (!Cp || !Ci || !Cx || !Cz)
    {
	error ("out of memory") ;
    }
    status = umfpack_zi_transpose (n, n, Ap, Ai, Ax, Az,
	(int *) NULL, (int *) NULL, Cp, Ci, Cx, Cz, TRUE) ;
    if (status < 0)
    {
	umfpack_zi_report_status (Control, status) ;
	error ("umfpack_zi_transpose failed: ") ;
    }
    printf ("\nC (transpose of A): ") ;
    (void) umfpack_zi_report_matrix (n, n, Cp, Ci, Cx, Cz, 1, Control) ;

    /* ---------------------------------------------------------------------- */
    /* symbolic factorization of C */
    /* ---------------------------------------------------------------------- */

    status = umfpack_zi_symbolic (n, n, Cp, Ci, Cx, Cz, &Symbolic,
	Control, Info) ;
    if (status < 0)
    {
	umfpack_zi_report_info (Control, Info) ;
	umfpack_zi_report_status (Control, status) ;
	error ("umfpack_zi_symbolic failed") ;
    }
    printf ("\nSymbolic factorization of C: ") ;
    (void) umfpack_zi_report_symbolic (Symbolic, Control) ;

    /* ---------------------------------------------------------------------- */
    /* copy the contents of Symbolic into user arrays print them */
    /* ---------------------------------------------------------------------- */

    printf ("\nGet the contents of the Symbolic object for C:\n") ;
    printf ("(compare with umfpack_zi_report_symbolic output, above)\n") ;
    Pinit = (int *) malloc ((n+1) * sizeof (int)) ;
    Qinit = (int *) malloc ((n+1) * sizeof (int)) ;
    Front_npivcol = (int *) malloc ((n+1) * sizeof (int)) ;
    Front_1strow = (int *) malloc ((n+1) * sizeof (int)) ;
    Front_leftmostdesc = (int *) malloc ((n+1) * sizeof (int)) ;
    Front_parent = (int *) malloc ((n+1) * sizeof (int)) ;
    Chain_start = (int *) malloc ((n+1) * sizeof (int)) ;
    Chain_maxrows = (int *) malloc ((n+1) * sizeof (int)) ;
    Chain_maxcols = (int *) malloc ((n+1) * sizeof (int)) ;
    if (!Pinit || !Qinit || !Front_npivcol || !Front_parent || !Chain_start ||
	!Chain_maxrows || !Chain_maxcols || !Front_1strow ||
	!Front_leftmostdesc)
    {
	error ("out of memory") ;
    }

    status = umfpack_zi_get_symbolic (&nr, &nc, &n1, &anz, &nfr, &nchains,
	Pinit, Qinit, Front_npivcol, Front_parent, Front_1strow,
	Front_leftmostdesc, Chain_start, Chain_maxrows, Chain_maxcols,
	Symbolic) ;

    if (status < 0)
    {
	error ("symbolic factorization invalid") ;
    }

    printf ("From the Symbolic object, C is of dimension %d-by-%d\n", nr, nc);
    printf ("   with nz = %d, number of fronts = %d,\n", nz, nfr) ;
    printf ("   number of frontal matrix chains = %d\n", nchains) ;

    printf ("\nPivot columns in each front, and parent of each front:\n") ;
    k = 0 ;
    for (i = 0 ; i < nfr ; i++)
    {
	fnpiv = Front_npivcol [i] ;
	printf ("    Front %d: parent front: %d number of pivot cols: %d\n",
		i, Front_parent [i], fnpiv) ;
	for (j = 0 ; j < fnpiv ; j++)
	{
	    col = Qinit [k] ;
	    printf (
	    "        %d-th pivot column is column %d in original matrix\n",
		k, col) ;
	    k++ ;
	}
    }

    printf ("\nNote that the column ordering, above, will be refined\n") ;
    printf ("in the numeric factorization below.  The assignment of pivot\n") ;
    printf ("columns to frontal matrices will always remain unchanged.\n") ;

    printf ("\nTotal number of pivot columns in frontal matrices: %d\n", k) ;

    printf ("\nFrontal matrix chains:\n") ;
    for (j = 0 ; j < nchains ; j++)
    {
	printf ("   Frontal matrices %d to %d are factorized in a single\n",
	    Chain_start [j], Chain_start [j+1] - 1) ;
	printf ("        working array of size %d-by-%d\n",
	    Chain_maxrows [j], Chain_maxcols [j]) ;
    }

    /* ---------------------------------------------------------------------- */
    /* numeric factorization of C */
    /* ---------------------------------------------------------------------- */

    status = umfpack_zi_numeric (Cp, Ci, Cx, Cz, Symbolic, &Numeric,
	Control, Info) ;
    if (status < 0)
    {
	error ("umfpack_zi_numeric failed") ;
    }
    printf ("\nNumeric factorization of C: ") ;
    (void) umfpack_zi_report_numeric (Numeric, Control) ;

    /* ---------------------------------------------------------------------- */
    /* extract the LU factors of C and print them */
    /* ---------------------------------------------------------------------- */

    if (umfpack_zi_get_lunz (&lnz, &unz, &nr, &nc, &nzud, Numeric) < 0)
    {
	error ("umfpack_zi_get_lunz failed") ;
    }
    /* ensure arrays are not of zero size */
    lnz1 = MAX (lnz,1) ;
    unz1 = MAX (unz,1) ;
    Lp = (int *) malloc ((n+1) * sizeof (int)) ;
    Lj = (int *) malloc (lnz1 * sizeof (int)) ;
    Lx = (double *) malloc (lnz1 * sizeof (double)) ;
    Lz = (double *) malloc (lnz1 * sizeof (double)) ;
    Up = (int *) malloc ((n+1) * sizeof (int)) ;
    Ui = (int *) malloc (unz1 * sizeof (int)) ;
    Ux = (double *) malloc (unz1 * sizeof (double)) ;
    Uz = (double *) malloc (unz1 * sizeof (double)) ;
    P = (int *) malloc (n * sizeof (int)) ;
    Q = (int *) malloc (n * sizeof (int)) ;
    Dx = (double *) NULL ;	/* D vector not requested */
    Dz = (double *) NULL ;
    Rs  = (double *) malloc (n * sizeof (double)) ;
    if (!Lp || !Lj || !Lx || !Lz || !Up || !Ui || !Ux || !Uz || !P || !Q || !Rs)
    {
	error ("out of memory") ;
    }
    status = umfpack_zi_get_numeric (Lp, Lj, Lx, Lz, Up, Ui, Ux, Uz,
	P, Q, Dx, Dz, &do_recip, Rs, Numeric) ;
    if (status < 0)
    {
	error ("umfpack_zi_get_numeric failed") ;
    }

    printf ("\nL (lower triangular factor of C): ") ;
    (void) umfpack_zi_report_matrix (n, n, Lp, Lj, Lx, Lz, 0, Control) ;
    printf ("\nU (upper triangular factor of C): ") ;
    (void) umfpack_zi_report_matrix (n, n, Up, Ui, Ux, Uz, 1, Control) ;
    printf ("\nP: ") ;
    (void) umfpack_zi_report_perm (n, P, Control) ;
    printf ("\nQ: ") ;
    (void) umfpack_zi_report_perm (n, Q, Control) ;
    printf ("\nScale factors: row i of A is to be ") ;
    if (do_recip)
    {
	printf ("multiplied by the ith scale factor\n") ;
    }
    else
    {
	printf ("divided by the ith scale factor\n") ;
    }
    for (i = 0 ; i < n ; i++) printf ("%d: %g\n", i, Rs [i]) ;

    /* ---------------------------------------------------------------------- */
    /* convert L to triplet form and print it */
    /* ---------------------------------------------------------------------- */

    /* Note that L is in row-form, so it is the row indices that are created */
    /* by umfpack_zi_col_to_triplet. */

    printf ("\nConverting L to triplet form, and printing it:\n") ;
    Li = (int *) malloc (lnz1 * sizeof (int)) ;
    if (!Li)
    {
	error ("out of memory") ;
    }
    if (umfpack_zi_col_to_triplet (n, Lp, Li) < 0)
    {
	error ("umfpack_zi_col_to_triplet failed") ;
    }
    printf ("\nL, in triplet form: ") ;
    (void) umfpack_zi_report_triplet (n, n, lnz, Li, Lj, Lx, Lz, Control) ;

    /* ---------------------------------------------------------------------- */
    /* save the Numeric object to file, free it, and load it back in */
    /* ---------------------------------------------------------------------- */

    /* use the default filename, "numeric.umf" */
    printf ("\nSaving numeric object:\n") ;
    status = umfpack_zi_save_numeric (Numeric, (char *) NULL) ;
    if (status < 0)
    {
	umfpack_zi_report_status (Control, status) ;
	error ("umfpack_zi_save_numeric failed") ;
    }
    printf ("\nFreeing numeric object:\n") ;
    umfpack_zi_free_numeric (&Numeric) ;
    printf ("\nLoading numeric object:\n") ;
    status = umfpack_zi_load_numeric (&Numeric, (char *) NULL) ;
    if (status < 0)
    {
	umfpack_zi_report_status (Control, status) ;
	error ("umfpack_zi_load_numeric failed") ;
    }
    printf ("\nDone loading numeric object\n") ;

    /* ---------------------------------------------------------------------- */
    /* solve C'x=b */
    /* ---------------------------------------------------------------------- */

    status = umfpack_zi_solve (UMFPACK_At, Cp, Ci, Cx, Cz, x, xz, b, bz,
	Numeric, Control, Info) ;
    umfpack_zi_report_info (Control, Info) ;
    if (status < 0)
    {
	umfpack_zi_report_status (Control, status) ;
	error ("umfpack_zi_solve failed") ;
    }
    printf ("\nx (solution of C'x=b): ") ;
    (void) umfpack_zi_report_vector (n, x, xz, Control) ;
    rnorm = resid (TRUE, Cp, Ci, Cx, Cz) ;
    printf ("maxnorm of residual: %g\n\n", rnorm) ;

    /* ---------------------------------------------------------------------- */
    /* solve C'x=b again, using umfpack_zi_wsolve instead */
    /* ---------------------------------------------------------------------- */

    printf ("\nSolving C'x=b again, using umfpack_zi_wsolve instead:\n") ;
    Wi = (int *) malloc (n * sizeof (int)) ;
    W = (double *) malloc (10*n * sizeof (double)) ;
    if (!Wi || !W)
    {
	error ("out of memory") ;
    }

    status = umfpack_zi_wsolve (UMFPACK_At, Cp, Ci, Cx, Cz, x, xz, b, bz,
	Numeric, Control, Info, Wi, W) ;
    umfpack_zi_report_info (Control, Info) ;
    if (status < 0)
    {
	umfpack_zi_report_status (Control, status) ;
	error ("umfpack_zi_wsolve failed") ;
    }
    printf ("\nx (solution of C'x=b): ") ;
    (void) umfpack_zi_report_vector (n, x, xz, Control) ;
    rnorm = resid (TRUE, Cp, Ci, Cx, Cz) ;
    printf ("maxnorm of residual: %g\n\n", rnorm) ;

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

    /* This is not strictly required since the process is exiting and the */
    /* system will reclaim the memory anyway.  It's useful, though, just as */
    /* a list of what is currently malloc'ed by this program.  Plus, it's */
    /* always a good habit to explicitly free whatever you malloc. */

    free (Ap) ;
    free (Ai) ;
    free (Ax) ;
    free (Az) ;

    free (Cp) ;
    free (Ci) ;
    free (Cx) ;
    free (Cz) ;

    free (Pinit) ;
    free (Qinit) ;
    free (Front_npivcol) ;
    free (Front_1strow) ;
    free (Front_leftmostdesc) ;
    free (Front_parent) ;
    free (Chain_start) ;
    free (Chain_maxrows) ;
    free (Chain_maxcols) ;

    free (Lp) ;
    free (Lj) ;
    free (Lx) ;
    free (Lz) ;

    free (Up) ;
    free (Ui) ;
    free (Ux) ;
    free (Uz) ;

    free (P) ;
    free (Q) ;

    free (Li) ;

    free (Wi) ;
    free (W) ;

    umfpack_zi_free_symbolic (&Symbolic) ;
    umfpack_zi_free_numeric (&Numeric) ;

    /* ---------------------------------------------------------------------- */
    /* print the total time spent in this demo */
    /* ---------------------------------------------------------------------- */

    umfpack_toc (t) ;
    printf ("\numfpack_zi_demo complete.\nTotal time: %5.2f seconds"
	" (CPU time), %5.2f seconds (wallclock time)\n", t [1], t [0]) ;
    return (0) ;
}