/*

 * -- SuperLU routine (version 3.0) --

 * Univ. of California Berkeley, Xerox Palo Alto Research Center,

 * and Lawrence Berkeley National Lab.

 * October 15, 2003

 *

 */

#include "slu_ddefs.h"

main(int argc, char *argv[])

{

/*

 * Purpose

 * =======

 *

 * The driver program DLINSOLX1.

 *

 * This example illustrates how to use DGSSVX to solve systems with the same

 * A but different right-hand side.

 * In this case, we factorize A only once in the first call to DGSSVX,

 * and reuse the following data structures in the subsequent call to DGSSVX:

 *     perm_c, perm_r, R, C, L, U.

 * 

 */

    char           equed[1];

    yes_no_t       equil;

    trans_t        trans;

    SuperMatrix    A, L, U;

    SuperMatrix    B, X;

    NCformat       *Astore;

    NCformat       *Ustore;

    SCformat       *Lstore;

    double         *a;

    int            *asub, *xa;

    int            *perm_c; /* column permutation vector */

    int            *perm_r; /* row permutations from partial pivoting */

    int            *etree;

    void           *work;

    int            info, lwork, nrhs, ldx;

    int            i, m, n, nnz;

    double         *rhsb, *rhsx, *xact;

    double         *R, *C;

    double         *ferr, *berr;

    double         u, rpg, rcond;

    mem_usage_t    mem_usage;

    superlu_options_t options;

    SuperLUStat_t stat;

    extern void    parse_command_line();

#if ( DEBUGlevel>=1 )

    CHECK_MALLOC("Enter main()");

#endif

    /* Defaults */

    lwork = 0;

    nrhs  = 1;

    equil = YES;	

    u     = 1.0;

    trans = NOTRANS;

    /* Set the default values for options argument:

	options.Fact = DOFACT;

        options.Equil = YES;

    	options.ColPerm = COLAMD;

	options.DiagPivotThresh = 1.0;

    	options.Trans = NOTRANS;

    	options.IterRefine = NOREFINE;

    	options.SymmetricMode = NO;

    	options.PivotGrowth = NO;

    	options.ConditionNumber = NO;

    	options.PrintStat = YES;

    */

    set_default_options(&options);

    /* Can use command line input to modify the defaults. */

    parse_command_line(argc, argv, &lwork, &u, &equil, &trans);

    options.Equil = equil;

    options.DiagPivotThresh = u;

    options.Trans = trans;

    if ( lwork > 0 ) {

	work = SUPERLU_MALLOC(lwork);

	if ( !work ) {

	    ABORT("DLINSOLX: cannot allocate work[]");

	}

    }

    /* Read matrix A from a file in Harwell-Boeing format.*/

    dreadhb(&m, &n, &nnz, &a, &asub, &xa);

    dCreate_CompCol_Matrix(&A, m, n, nnz, a, asub, xa, SLU_NC, SLU_D, SLU_GE);

    Astore = A.Store;

    printf("Dimension %dx%d; # nonzeros %d\n", A.nrow, A.ncol, Astore->nnz);

    if ( !(rhsb = doubleMalloc(m * nrhs)) ) ABORT("Malloc fails for rhsb[].");

    if ( !(rhsx = doubleMalloc(m * nrhs)) ) ABORT("Malloc fails for rhsx[].");

    dCreate_Dense_Matrix(&B, m, nrhs, rhsb, m, SLU_DN, SLU_D, SLU_GE);

    dCreate_Dense_Matrix(&X, m, nrhs, rhsx, m, SLU_DN, SLU_D, SLU_GE);

    xact = doubleMalloc(n * nrhs);

    ldx = n;

    dGenXtrue(n, nrhs, xact, ldx);

    dFillRHS(trans, nrhs, xact, ldx, &A, &B);

    if ( !(etree = intMalloc(n)) ) ABORT("Malloc fails for etree[].");

    if ( !(perm_r = intMalloc(m)) ) ABORT("Malloc fails for perm_r[].");

    if ( !(perm_c = intMalloc(n)) ) ABORT("Malloc fails for perm_c[].");

    if ( !(R = (double *) SUPERLU_MALLOC(A.nrow * sizeof(double))) ) 

        ABORT("SUPERLU_MALLOC fails for R[].");

    if ( !(C = (double *) SUPERLU_MALLOC(A.ncol * sizeof(double))) )

        ABORT("SUPERLU_MALLOC fails for C[].");

    if ( !(ferr = (double *) SUPERLU_MALLOC(nrhs * sizeof(double))) )

        ABORT("SUPERLU_MALLOC fails for ferr[].");

    if ( !(berr = (double *) SUPERLU_MALLOC(nrhs * sizeof(double))) ) 

        ABORT("SUPERLU_MALLOC fails for berr[].");

    /* Initialize the statistics variables. */

    StatInit(&stat);

    /* ONLY PERFORM THE LU DECOMPOSITION */

    B.ncol = 0;  /* Indicate not to solve the system */

    dgssvx(&options, &A, perm_c, perm_r, etree, equed, R, C,

           &L, &U, work, lwork, &B, &X, &rpg, &rcond, ferr, berr,

           &mem_usage, &stat, &info);

    printf("LU factorization: dgssvx() returns info %d\n", info);

    if ( info == 0 || info == n+1 ) {

	if ( options.PivotGrowth ) printf("Recip. pivot growth = %e\n", rpg);

	if ( options.ConditionNumber )

	    printf("Recip. condition number = %e\n", rcond);

        Lstore = (SCformat *) L.Store;

        Ustore = (NCformat *) U.Store;

	printf("No of nonzeros in factor L = %d\n", Lstore->nnz);

    	printf("No of nonzeros in factor U = %d\n", Ustore->nnz);

    	printf("No of nonzeros in L+U = %d\n", Lstore->nnz + Ustore->nnz - n);

    	printf("FILL ratio = %.1f\n", (float)(Lstore->nnz + Ustore->nnz - n)/nnz);

	printf("L\\U MB %.3f\ttotal MB needed %.3f\n",

	       mem_usage.for_lu/1e6, mem_usage.total_needed/1e6);

	fflush(stdout);

    } else if ( info > 0 && lwork == -1 ) {

        printf("** Estimated memory: %d bytes\n", info - n);

    }

    if ( options.PrintStat ) StatPrint(&stat);

    StatFree(&stat);

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

       NOW WE SOLVE THE LINEAR SYSTEM USING THE FACTORED FORM OF A.

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

    options.Fact = FACTORED; /* Indicate the factored form of A is supplied. */

    B.ncol = nrhs;  /* Set the number of right-hand side */

    /* Initialize the statistics variables. */

    StatInit(&stat);

    dgssvx(&options, &A, perm_c, perm_r, etree, equed, R, C,

           &L, &U, work, lwork, &B, &X, &rpg, &rcond, ferr, berr,

           &mem_usage, &stat, &info);

    printf("Triangular solve: dgssvx() returns info %d\n", info);

    if ( info == 0 || info == n+1 ) {

        /* This is how you could access the solution matrix. */

        double *sol = (double*) ((DNformat*) X.Store)->nzval; 

	if ( options.IterRefine ) {

            printf("Iterative Refinement:\n");

	    printf("%8s%8s%16s%16s\n", "rhs", "Steps", "FERR", "BERR");

	    for (i = 0; i < nrhs; ++i)

	      printf("%8d%8d%16e%16e\n", i+1, stat.RefineSteps, ferr[i], berr[i]);

	}

	fflush(stdout);

    } else if ( info > 0 && lwork == -1 ) {

        printf("** Estimated memory: %d bytes\n", info - n);

    }

    if ( options.PrintStat ) StatPrint(&stat);

    StatFree(&stat);

    SUPERLU_FREE (rhsb);

    SUPERLU_FREE (rhsx);

    SUPERLU_FREE (xact);

    SUPERLU_FREE (etree);

    SUPERLU_FREE (perm_r);

    SUPERLU_FREE (perm_c);

    SUPERLU_FREE (R);

    SUPERLU_FREE (C);

    SUPERLU_FREE (ferr);

    SUPERLU_FREE (berr);

    Destroy_CompCol_Matrix(&A);

    Destroy_SuperMatrix_Store(&B);

    Destroy_SuperMatrix_Store(&X);

    if ( lwork == 0 ) {

        Destroy_SuperNode_Matrix(&L);

        Destroy_CompCol_Matrix(&U);

    } else if ( lwork > 0 ) {

        SUPERLU_FREE(work);

    }

#if ( DEBUGlevel>=1 )

    CHECK_MALLOC("Exit main()");

#endif

}

/*  

 * Parse command line options to get relaxed snode size, panel size, etc.

 */

void

parse_command_line(int argc, char *argv[], int *lwork,

                   double *u, yes_no_t *equil, trans_t *trans )

{

    int c;

    extern char *optarg;

    while ( (c = getopt(argc, argv, "hl:u:e:t:")) != EOF ) {

	switch (c) {

	  case 'h':

	    printf("Options:\n");

	    printf("\t-l <int> - length of work[*] array\n");</int>

	    printf("\t-u <int> - pivoting threshold\n");</int>

	    printf("\t-e <0 or 1> - equilibrate or not\n");

	    printf("\t-t <0 or 1> - solve transposed system or not\n");

	    exit(1);

	    break;

	  case 'l': *lwork = atoi(optarg);

	            break;

	  case 'u': *u = atof(optarg); 

	            break;

	  case 'e': *equil = atoi(optarg); 

	            break;

	  case 't': *trans = atoi(optarg);

	            break;

  	}

    }

}