/*! @file util.c
 * \brief Utility functions
 * 
 * <pre>
 * -- SuperLU routine (version 4.1) --
 * Univ. of California Berkeley, Xerox Palo Alto Research Center,
 * and Lawrence Berkeley National Lab.
 * November, 2010
 *
 * Copyright (c) 1994 by Xerox Corporation.  All rights reserved.
 *
 * THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY
 * EXPRESSED OR IMPLIED.  ANY USE IS AT YOUR OWN RISK.
 *
 * Permission is hereby granted to use or copy this program for any
 * purpose, provided the above notices are retained on all copies.
 * Permission to modify the code and to distribute modified code is
 * granted, provided the above notices are retained, and a notice that
 * the code was modified is included with the above copyright notice.
 * </pre>
 */


#include <math.h>
#include "slu_ddefs.h"

/*! \brief Global statistics variale
 */

void superlu_abort_and_exit(char* msg)
{
    fprintf(stderr, msg);
    exit (-1);
}

/*! \brief Set the default values for the options argument.
 */
void set_default_options(superlu_options_t *options)
{
    options->Fact = DOFACT;
    options->Equil = YES;
    options->ColPerm = COLAMD;
    options->Trans = NOTRANS;
    options->IterRefine = NOREFINE;
    options->DiagPivotThresh = 1.0;
    options->SymmetricMode = NO;
    options->PivotGrowth = NO;
    options->ConditionNumber = NO;
    options->PrintStat = YES;
}

/*! \brief Set the default values for the options argument for ILU.
 */
void ilu_set_default_options(superlu_options_t *options)
{
    set_default_options(options);

    /* further options for incomplete factorization */
    options->DiagPivotThresh = 0.1;
    options->RowPerm = LargeDiag;
    options->ILU_DropRule = DROP_BASIC | DROP_AREA;
    options->ILU_DropTol = 1e-4;
    options->ILU_FillFactor = 10.0;
    options->ILU_Norm = INF_NORM;
    options->ILU_MILU = SILU;
    options->ILU_MILU_Dim = 3.0; /* -log(n)/log(h) is perfect */
    options->ILU_FillTol = 1e-2;
}

/*! \brief Print the options setting.
 */
void print_options(superlu_options_t *options)
{
    printf(".. options:\n");
    printf("\tFact\t %8d\n", options->Fact);
    printf("\tEquil\t %8d\n", options->Equil);
    printf("\tColPerm\t %8d\n", options->ColPerm);
    printf("\tDiagPivotThresh %8.4f\n", options->DiagPivotThresh);
    printf("\tTrans\t %8d\n", options->Trans);
    printf("\tIterRefine\t%4d\n", options->IterRefine);
    printf("\tSymmetricMode\t%4d\n", options->SymmetricMode);
    printf("\tPivotGrowth\t%4d\n", options->PivotGrowth);
    printf("\tConditionNumber\t%4d\n", options->ConditionNumber);
    printf("..\n");
}

/*! \brief Print the options setting.
 */
void print_ilu_options(superlu_options_t *options)
{
    printf(".. ILU options:\n");
    printf("\tDiagPivotThresh\t%6.2e\n", options->DiagPivotThresh);
    printf("\ttau\t%6.2e\n", options->ILU_DropTol);
    printf("\tgamma\t%6.2f\n", options->ILU_FillFactor);
    printf("\tDropRule\t%0x\n", options->ILU_DropRule);
    printf("\tMILU\t%d\n", options->ILU_MILU);
    printf("\tMILU_ALPHA\t%6.2e\n", MILU_ALPHA);
    printf("\tDiagFillTol\t%6.2e\n", options->ILU_FillTol);
    printf("..\n");
}

/*! \brief Deallocate the structure pointing to the actual storage of the matrix. */
void
Destroy_SuperMatrix_Store(SuperMatrix *A)
{
    SUPERLU_FREE ( A->Store );
}

void
Destroy_CompCol_Matrix(SuperMatrix *A)
{
    SUPERLU_FREE( ((NCformat *)A->Store)->rowind );
    SUPERLU_FREE( ((NCformat *)A->Store)->colptr );
    SUPERLU_FREE( ((NCformat *)A->Store)->nzval );
    SUPERLU_FREE( A->Store );
}

void
Destroy_CompRow_Matrix(SuperMatrix *A)
{
    SUPERLU_FREE( ((NRformat *)A->Store)->colind );
    SUPERLU_FREE( ((NRformat *)A->Store)->rowptr );
    SUPERLU_FREE( ((NRformat *)A->Store)->nzval );
    SUPERLU_FREE( A->Store );
}

void
Destroy_SuperNode_Matrix(SuperMatrix *A)
{
    SUPERLU_FREE ( ((SCformat *)A->Store)->rowind );
    SUPERLU_FREE ( ((SCformat *)A->Store)->rowind_colptr );
    SUPERLU_FREE ( ((SCformat *)A->Store)->nzval );
    SUPERLU_FREE ( ((SCformat *)A->Store)->nzval_colptr );
    SUPERLU_FREE ( ((SCformat *)A->Store)->col_to_sup );
    SUPERLU_FREE ( ((SCformat *)A->Store)->sup_to_col );
    SUPERLU_FREE ( A->Store );
}

/*! \brief A is of type Stype==NCP */
void
Destroy_CompCol_Permuted(SuperMatrix *A)
{
    SUPERLU_FREE ( ((NCPformat *)A->Store)->colbeg );
    SUPERLU_FREE ( ((NCPformat *)A->Store)->colend );
    SUPERLU_FREE ( A->Store );
}

/*! \brief A is of type Stype==DN */
void
Destroy_Dense_Matrix(SuperMatrix *A)
{
    DNformat* Astore = A->Store;
    SUPERLU_FREE (Astore->nzval);
    SUPERLU_FREE ( A->Store );
}

/*! \brief Reset repfnz[] for the current column 
 */
void
resetrep_col (const int nseg, const int *segrep, int *repfnz)
{
    int i, irep;
    
    for (i = 0; i < nseg; i++) {
	irep = segrep[i];
	repfnz[irep] = EMPTY;
    }
}


/*! \brief Count the total number of nonzeros in factors L and U,  and in the symmetrically reduced L. 
 */
void
countnz(const int n, int *xprune, int *nnzL, int *nnzU, GlobalLU_t *Glu)
{
    int          nsuper, fsupc, i, j;
    int          nnzL0, jlen, irep;
    int          *xsup, *xlsub;

    xsup   = Glu->xsup;
    xlsub  = Glu->xlsub;
    *nnzL  = 0;
    *nnzU  = (Glu->xusub)[n];
    nnzL0  = 0;
    nsuper = (Glu->supno)[n];

    if ( n <= 0 ) return;

    /* 
     * For each supernode
     */
    for (i = 0; i <= nsuper; i++) {
	fsupc = xsup[i];
	jlen = xlsub[fsupc+1] - xlsub[fsupc];

	for (j = fsupc; j < xsup[i+1]; j++) {
	    *nnzL += jlen;
	    *nnzU += j - fsupc + 1;
	    jlen--;
	}
	irep = xsup[i+1] - 1;
	nnzL0 += xprune[irep] - xlsub[irep];
    }
    
    /* printf("\tNo of nonzeros in symm-reduced L = %d\n", nnzL0);*/
}

/*! \brief Count the total number of nonzeros in factors L and U.
 */
void
ilu_countnz(const int n, int *nnzL, int *nnzU, GlobalLU_t *Glu)
{
    int          nsuper, fsupc, i, j;
    int          jlen, irep;
    int          *xsup, *xlsub;

    xsup   = Glu->xsup;
    xlsub  = Glu->xlsub;
    *nnzL  = 0;
    *nnzU  = (Glu->xusub)[n];
    nsuper = (Glu->supno)[n];

    if ( n <= 0 ) return;

    /*
     * For each supernode
     */
    for (i = 0; i <= nsuper; i++) {
	fsupc = xsup[i];
	jlen = xlsub[fsupc+1] - xlsub[fsupc];

	for (j = fsupc; j < xsup[i+1]; j++) {
	    *nnzL += jlen;
	    *nnzU += j - fsupc + 1;
	    jlen--;
	}
	irep = xsup[i+1] - 1;
    }
}


/*! \brief Fix up the data storage lsub for L-subscripts. It removes the subscript sets for structural pruning,	and applies permuation to the remaining subscripts.
 */
void
fixupL(const int n, const int *perm_r, GlobalLU_t *Glu)
{
    register int nsuper, fsupc, nextl, i, j, k, jstrt;
    int          *xsup, *lsub, *xlsub;

    if ( n <= 1 ) return;

    xsup   = Glu->xsup;
    lsub   = Glu->lsub;
    xlsub  = Glu->xlsub;
    nextl  = 0;
    nsuper = (Glu->supno)[n];
    
    /* 
     * For each supernode ...
     */
    for (i = 0; i <= nsuper; i++) {
	fsupc = xsup[i];
	jstrt = xlsub[fsupc];
	xlsub[fsupc] = nextl;
	for (j = jstrt; j < xlsub[fsupc+1]; j++) {
	    lsub[nextl] = perm_r[lsub[j]]; /* Now indexed into P*A */
	    nextl++;
  	}
	for (k = fsupc+1; k < xsup[i+1]; k++) 
	    	xlsub[k] = nextl;	/* Other columns in supernode i */

    }

    xlsub[n] = nextl;
}


/*! \brief Diagnostic print of segment info after panel_dfs().
 */
void print_panel_seg(int n, int w, int jcol, int nseg, 
		     int *segrep, int *repfnz)
{
    int j, k;
    
    for (j = jcol; j < jcol+w; j++) {
	printf("\tcol %d:\n", j);
	for (k = 0; k < nseg; k++)
	    printf("\t\tseg %d, segrep %d, repfnz %d\n", k, 
			segrep[k], repfnz[(j-jcol)*n + segrep[k]]);
    }

}


void
StatInit(SuperLUStat_t *stat)
{
    register int i, w, panel_size, relax;

    panel_size = sp_ienv(1);
    relax = sp_ienv(2);
    w = SUPERLU_MAX(panel_size, relax);
    stat->panel_histo = intCalloc(w+1);
    stat->utime = (double *) SUPERLU_MALLOC(NPHASES * sizeof(double));
    if (!stat->utime) ABORT("SUPERLU_MALLOC fails for stat->utime");
    stat->ops = (flops_t *) SUPERLU_MALLOC(NPHASES * sizeof(flops_t));
    if (!stat->ops) ABORT("SUPERLU_MALLOC fails for stat->ops");
    for (i = 0; i < NPHASES; ++i) {
        stat->utime[i] = 0.;
        stat->ops[i] = 0.;
    }
    stat->TinyPivots = 0;
    stat->RefineSteps = 0;
    stat->expansions = 0;
#if ( PRNTlevel >= 1 )
    printf(".. parameters in sp_ienv():\n");
    printf("\t 1: panel size \t %4d \n"
           "\t 2: relax      \t %4d \n"
           "\t 3: max. super \t %4d \n"
           "\t 4: row-dim 2D \t %4d \n"
           "\t 5: col-dim 2D \t %4d \n"
           "\t 6: fill ratio \t %4d \n",
	   sp_ienv(1), sp_ienv(2), sp_ienv(3), 
	   sp_ienv(4), sp_ienv(5), sp_ienv(6));
#endif
}


void
StatPrint(SuperLUStat_t *stat)
{
    double         *utime;
    flops_t        *ops;

    utime = stat->utime;
    ops   = stat->ops;
    printf("Factor time  = %8.2f\n", utime[FACT]);
    if ( utime[FACT] != 0.0 )
      printf("Factor flops = %e\tMflops = %8.2f\n", ops[FACT],
	     ops[FACT]*1e-6/utime[FACT]);

    printf("Solve time   = %8.2f\n", utime[SOLVE]);
    if ( utime[SOLVE] != 0.0 )
      printf("Solve flops = %e\tMflops = %8.2f\n", ops[SOLVE],
	     ops[SOLVE]*1e-6/utime[SOLVE]);

    printf("Number of memory expansions: %d\n", stat->expansions);

}


void
StatFree(SuperLUStat_t *stat)
{
    SUPERLU_FREE(stat->panel_histo);
    SUPERLU_FREE(stat->utime);
    SUPERLU_FREE(stat->ops);
}


flops_t
LUFactFlops(SuperLUStat_t *stat)
{
    return (stat->ops[FACT]);
}

flops_t
LUSolveFlops(SuperLUStat_t *stat)
{
    return (stat->ops[SOLVE]);
}





/*! \brief Fills an integer array with a given value.
 */
void ifill(int *a, int alen, int ival)
{
    register int i;
    for (i = 0; i < alen; i++) a[i] = ival;
}



/*! \brief Get the statistics of the supernodes 
 */
#define NBUCKS 10
static 	int	max_sup_size;

void super_stats(int nsuper, int *xsup)
{
    register int nsup1 = 0;
    int          i, isize, whichb, bl, bh;
    int          bucket[NBUCKS];

    max_sup_size = 0;

    for (i = 0; i <= nsuper; i++) {
	isize = xsup[i+1] - xsup[i];
	if ( isize == 1 ) nsup1++;
	if ( max_sup_size < isize ) max_sup_size = isize;	
    }

    printf("    Supernode statistics:\n\tno of super = %d\n", nsuper+1);
    printf("\tmax supernode size = %d\n", max_sup_size);
    printf("\tno of size 1 supernodes = %d\n", nsup1);

    /* Histogram of the supernode sizes */
    ifill (bucket, NBUCKS, 0);

    for (i = 0; i <= nsuper; i++) {
        isize = xsup[i+1] - xsup[i];
        whichb = (float) isize / max_sup_size * NBUCKS;
        if (whichb >= NBUCKS) whichb = NBUCKS - 1;
        bucket[whichb]++;
    }
    
    printf("\tHistogram of supernode sizes:\n");
    for (i = 0; i < NBUCKS; i++) {
        bl = (float) i * max_sup_size / NBUCKS;
        bh = (float) (i+1) * max_sup_size / NBUCKS;
        printf("\tsnode: %d-%d\t\t%d\n", bl+1, bh, bucket[i]);
    }

}


float SpaSize(int n, int np, float sum_npw)
{
    return (sum_npw*8 + np*8 + n*4)/1024.;
}

float DenseSize(int n, float sum_nw)
{
    return (sum_nw*8 + n*8)/1024.;;
}



/*! \brief Check whether repfnz[] == EMPTY after reset.
 */
void check_repfnz(int n, int w, int jcol, int *repfnz)
{
    int jj, k;

    for (jj = jcol; jj < jcol+w; jj++) 
	for (k = 0; k < n; k++)
	    if ( repfnz[(jj-jcol)*n + k] != EMPTY ) {
		fprintf(stderr, "col %d, repfnz_col[%d] = %d\n", jj,
			k, repfnz[(jj-jcol)*n + k]);
		ABORT("check_repfnz");
	    }
}


/*! \brief Print a summary of the testing results. */
void
PrintSumm(char *type, int nfail, int nrun, int nerrs)
{
    if ( nfail > 0 )
	printf("%3s driver: %d out of %d tests failed to pass the threshold\n",
	       type, nfail, nrun);
    else
	printf("All tests for %3s driver passed the threshold (%6d tests run)\n", type, nrun);

    if ( nerrs > 0 )
	printf("%6d error messages recorded\n", nerrs);
}


int print_int_vec(char *what, int n, int *vec)
{
    int i;
    printf("%s\n", what);
    for (i = 0; i < n; ++i) printf("%d\t%d\n", i, vec[i]);
    return 0;
}

int slu_PrintInt10(char *name, int len, int *x)
{
    register int i;
    
    printf("%10s:", name);
    for (i = 0; i < len; ++i)
    {
	if ( i % 10 == 0 ) printf("\n\t[%2d-%2d]", i, i + 9);
	printf("%6d", x[i]);
    }
    printf("\n");
    return 0;
}