/*! @file zmemory.c

 * \brief Memory details

 *

 * 

 * -- SuperLU routine (version 4.0) --

 * Lawrence Berkeley National Laboratory.

 * June 30, 2009

 * 

 */

#include "slu_zdefs.h"

/* Internal prototypes */

void  *zexpand (int *, MemType,int, int, GlobalLU_t *);

int   zLUWorkInit (int, int, int, int **, doublecomplex **, GlobalLU_t *);

void  copy_mem_doublecomplex (int, void *, void *);

void  zStackCompress (GlobalLU_t *);

void  zSetupSpace (void *, int, GlobalLU_t *);

void  *zuser_malloc (int, int, GlobalLU_t *);

void  zuser_free (int, int, GlobalLU_t *);

/* External prototypes (in memory.c - prec-independent) */

extern void    copy_mem_int    (int, void *, void *);

extern void    user_bcopy      (char *, char *, int);

/* Macros to manipulate stack */

#define StackFull(x)         ( x + Glu->stack.used >= Glu->stack.size )

#define NotDoubleAlign(addr) ( (long int)addr & 7 )

#define DoubleAlign(addr)    ( ((long int)addr + 7) & ~7L )

#define TempSpace(m, w)      ( (2*w + 4 + NO_MARKER) * m * sizeof(int) + \

			      (w + 1) * m * sizeof(doublecomplex) )

#define Reduce(alpha)        ((alpha + 1) / 2)  /* i.e. (alpha-1)/2 + 1 */

/*! \brief Setup the memory model to be used for factorization.

 *  

 *    lwork = 0: use system malloc;

 *    lwork > 0: use user-supplied work[] space.

 */

void zSetupSpace(void *work, int lwork, GlobalLU_t *Glu)

{

    if ( lwork == 0 ) {

	Glu->MemModel = SYSTEM; /* malloc/free */

    } else if ( lwork > 0 ) {

	Glu->MemModel = USER;   /* user provided space */

	Glu->stack.used = 0;

	Glu->stack.top1 = 0;

	Glu->stack.top2 = (lwork/4)*4; /* must be word addressable */

	Glu->stack.size = Glu->stack.top2;

	Glu->stack.array = (void *) work;

    }

}

void *zuser_malloc(int bytes, int which_end, GlobalLU_t *Glu)

{

    void *buf;

    if ( StackFull(bytes) ) return (NULL);

    if ( which_end == HEAD ) {

	buf = (char*) Glu->stack.array + Glu->stack.top1;

	Glu->stack.top1 += bytes;

    } else {

	Glu->stack.top2 -= bytes;

	buf = (char*) Glu->stack.array + Glu->stack.top2;

    }

    Glu->stack.used += bytes;

    return buf;

}

void zuser_free(int bytes, int which_end, GlobalLU_t *Glu)

{

    if ( which_end == HEAD ) {

	Glu->stack.top1 -= bytes;

    } else {

	Glu->stack.top2 += bytes;

    }

    Glu->stack.used -= bytes;

}

/*! \brief 

 *

 * 

 * mem_usage consists of the following fields:

 *    - for_lu (float)

 *      The amount of space used in bytes for the L\U data structures.

 *    - total_needed (float)

 *      The amount of space needed in bytes to perform factorization.

 * 

 */

int zQuerySpace(SuperMatrix *L, SuperMatrix *U, mem_usage_t *mem_usage)

{

    SCformat *Lstore;

    NCformat *Ustore;

    register int n, iword, dword, panel_size = sp_ienv(1);

    Lstore = L->Store;

    Ustore = U->Store;

    n = L->ncol;

    iword = sizeof(int);

    dword = sizeof(doublecomplex);

    /* For LU factors */

    mem_usage->for_lu = (float)( (4.0*n + 3.0) * iword +

                                 Lstore->nzval_colptr[n] * dword +

                                 Lstore->rowind_colptr[n] * iword );

    mem_usage->for_lu += (float)( (n + 1.0) * iword +

				 Ustore->colptr[n] * (dword + iword) );

    /* Working storage to support factorization */

    mem_usage->total_needed = mem_usage->for_lu +

	(float)( (2.0 * panel_size + 4.0 + NO_MARKER) * n * iword +

		(panel_size + 1.0) * n * dword );

    return 0;

} /* zQuerySpace */

/*! \brief

 *

 * 

 * mem_usage consists of the following fields:

 *    - for_lu (float)

 *      The amount of space used in bytes for the L\U data structures.

 *    - total_needed (float)

 *      The amount of space needed in bytes to perform factorization.

 * 

 */

int ilu_zQuerySpace(SuperMatrix *L, SuperMatrix *U, mem_usage_t *mem_usage)

{

    SCformat *Lstore;

    NCformat *Ustore;

    register int n, panel_size = sp_ienv(1);

    register float iword, dword;

    Lstore = L->Store;

    Ustore = U->Store;

    n = L->ncol;

    iword = sizeof(int);

    dword = sizeof(double);

    /* For LU factors */

    mem_usage->for_lu = (float)( (4.0f * n + 3.0f) * iword +

				 Lstore->nzval_colptr[n] * dword +

				 Lstore->rowind_colptr[n] * iword );

    mem_usage->for_lu += (float)( (n + 1.0f) * iword +

				 Ustore->colptr[n] * (dword + iword) );

    /* Working storage to support factorization.

       ILU needs 5*n more integers than LU */

    mem_usage->total_needed = mem_usage->for_lu +

	(float)( (2.0f * panel_size + 9.0f + NO_MARKER) * n * iword +

		(panel_size + 1.0f) * n * dword );

    return 0;

} /* ilu_zQuerySpace */

/*! \brief Allocate storage for the data structures common to all factor routines.

 *

 * 

 * For those unpredictable size, estimate as fill_ratio * nnz(A).

 * Return value:

 *     If lwork = -1, return the estimated amount of space required, plus n;

 *     otherwise, return the amount of space actually allocated when

 *     memory allocation failure occurred.

 *  

 */

int

zLUMemInit(fact_t fact, void *work, int lwork, int m, int n, int annz,

	  int panel_size, double fill_ratio, SuperMatrix *L, SuperMatrix *U,

          GlobalLU_t *Glu, int **iwork, doublecomplex **dwork)

{

    int      info, iword, dword;

    SCformat *Lstore;

    NCformat *Ustore;

    int      *xsup, *supno;

    int      *lsub, *xlsub;

    doublecomplex   *lusup;

    int      *xlusup;

    doublecomplex   *ucol;

    int      *usub, *xusub;

    int      nzlmax, nzumax, nzlumax;

    iword     = sizeof(int);

    dword     = sizeof(doublecomplex);

    Glu->n    = n;

    Glu->num_expansions = 0;

    if ( !Glu->expanders )	

        Glu->expanders = (ExpHeader*)SUPERLU_MALLOC( NO_MEMTYPE *

                                                     sizeof(ExpHeader) );

    if ( !Glu->expanders ) ABORT("SUPERLU_MALLOC fails for expanders");

    if ( fact != SamePattern_SameRowPerm ) {

	/* Guess for L\U factors */

	nzumax = nzlumax = fill_ratio * annz;

	nzlmax = SUPERLU_MAX(1, fill_ratio/4.) * annz;

	if ( lwork == -1 ) {

	    return ( GluIntArray(n) * iword + TempSpace(m, panel_size)

		    + (nzlmax+nzumax)*iword + (nzlumax+nzumax)*dword + n );

        } else {

	    zSetupSpace(work, lwork, Glu);

	}

#if ( PRNTlevel >= 1 )

	printf("zLUMemInit() called: fill_ratio %.0f, nzlmax %ld, nzumax %ld\n", 

	       fill_ratio, nzlmax, nzumax);

	fflush(stdout);

#endif	

	/* Integer pointers for L\U factors */

	if ( Glu->MemModel == SYSTEM ) {

	    xsup   = intMalloc(n+1);

	    supno  = intMalloc(n+1);

	    xlsub  = intMalloc(n+1);

	    xlusup = intMalloc(n+1);

	    xusub  = intMalloc(n+1);

	} else {

	    xsup   = (int *)zuser_malloc((n+1) * iword, HEAD, Glu);

	    supno  = (int *)zuser_malloc((n+1) * iword, HEAD, Glu);

	    xlsub  = (int *)zuser_malloc((n+1) * iword, HEAD, Glu);

	    xlusup = (int *)zuser_malloc((n+1) * iword, HEAD, Glu);

	    xusub  = (int *)zuser_malloc((n+1) * iword, HEAD, Glu);

	}

	lusup = (doublecomplex *) zexpand( &nzlumax, LUSUP, 0, 0, Glu );

	ucol  = (doublecomplex *) zexpand( &nzumax, UCOL, 0, 0, Glu );

	lsub  = (int *)    zexpand( &nzlmax, LSUB, 0, 0, Glu );

	usub  = (int *)    zexpand( &nzumax, USUB, 0, 1, Glu );

	while ( !lusup || !ucol || !lsub || !usub ) {

	    if ( Glu->MemModel == SYSTEM ) {

		SUPERLU_FREE(lusup); 

		SUPERLU_FREE(ucol); 

		SUPERLU_FREE(lsub); 

		SUPERLU_FREE(usub);

	    } else {

		zuser_free((nzlumax+nzumax)*dword+(nzlmax+nzumax)*iword,

                            HEAD, Glu);

	    }

	    nzlumax /= 2;

	    nzumax /= 2;

	    nzlmax /= 2;

	    if ( nzlumax < annz ) {

		printf("Not enough memory to perform factorization.\n");

		return (zmemory_usage(nzlmax, nzumax, nzlumax, n) + n);

	    }

#if ( PRNTlevel >= 1)

	    printf("zLUMemInit() reduce size: nzlmax %ld, nzumax %ld\n", 

		   nzlmax, nzumax);

	    fflush(stdout);

#endif

	    lusup = (doublecomplex *) zexpand( &nzlumax, LUSUP, 0, 0, Glu );

	    ucol  = (doublecomplex *) zexpand( &nzumax, UCOL, 0, 0, Glu );

	    lsub  = (int *)    zexpand( &nzlmax, LSUB, 0, 0, Glu );

	    usub  = (int *)    zexpand( &nzumax, USUB, 0, 1, Glu );

	}

    } else {

	/* fact == SamePattern_SameRowPerm */

	Lstore   = L->Store;

	Ustore   = U->Store;

	xsup     = Lstore->sup_to_col;

	supno    = Lstore->col_to_sup;

	xlsub    = Lstore->rowind_colptr;

	xlusup   = Lstore->nzval_colptr;

	xusub    = Ustore->colptr;

	nzlmax   = Glu->nzlmax;    /* max from previous factorization */

	nzumax   = Glu->nzumax;

	nzlumax  = Glu->nzlumax;

	if ( lwork == -1 ) {

	    return ( GluIntArray(n) * iword + TempSpace(m, panel_size)

		    + (nzlmax+nzumax)*iword + (nzlumax+nzumax)*dword + n );

        } else if ( lwork == 0 ) {

	    Glu->MemModel = SYSTEM;

	} else {

	    Glu->MemModel = USER;

	    Glu->stack.top2 = (lwork/4)*4; /* must be word-addressable */

	    Glu->stack.size = Glu->stack.top2;

	}

	lsub  = Glu->expanders[LSUB].mem  = Lstore->rowind;

	lusup = Glu->expanders[LUSUP].mem = Lstore->nzval;

	usub  = Glu->expanders[USUB].mem  = Ustore->rowind;

	ucol  = Glu->expanders[UCOL].mem  = Ustore->nzval;;

	Glu->expanders[LSUB].size         = nzlmax;

	Glu->expanders[LUSUP].size        = nzlumax;

	Glu->expanders[USUB].size         = nzumax;

	Glu->expanders[UCOL].size         = nzumax;	

    }

    Glu->xsup    = xsup;

    Glu->supno   = supno;

    Glu->lsub    = lsub;

    Glu->xlsub   = xlsub;

    Glu->lusup   = lusup;

    Glu->xlusup  = xlusup;

    Glu->ucol    = ucol;

    Glu->usub    = usub;

    Glu->xusub   = xusub;

    Glu->nzlmax  = nzlmax;

    Glu->nzumax  = nzumax;

    Glu->nzlumax = nzlumax;

    info = zLUWorkInit(m, n, panel_size, iwork, dwork, Glu);

    if ( info )

	return ( info + zmemory_usage(nzlmax, nzumax, nzlumax, n) + n);

    ++Glu->num_expansions;

    return 0;

} /* zLUMemInit */

/*! \brief Allocate known working storage. Returns 0 if success, otherwise

   returns the number of bytes allocated so far when failure occurred. */

int

zLUWorkInit(int m, int n, int panel_size, int **iworkptr, 

            doublecomplex **dworkptr, GlobalLU_t *Glu)

{

    int    isize, dsize, extra;

    doublecomplex *old_ptr;

    int    maxsuper = SUPERLU_MAX( sp_ienv(3), sp_ienv(7) ),

           rowblk   = sp_ienv(4);

    isize = ( (2 * panel_size + 3 + NO_MARKER ) * m + n ) * sizeof(int);

    dsize = (m * panel_size +

	     NUM_TEMPV(m,panel_size,maxsuper,rowblk)) * sizeof(doublecomplex);

    if ( Glu->MemModel == SYSTEM ) 

	*iworkptr = (int *) intCalloc(isize/sizeof(int));

    else

	*iworkptr = (int *) zuser_malloc(isize, TAIL, Glu);

    if ( ! *iworkptr ) {

	fprintf(stderr, "zLUWorkInit: malloc fails for local iworkptr[]\n");

	return (isize + n);

    }

    if ( Glu->MemModel == SYSTEM )

	*dworkptr = (doublecomplex *) SUPERLU_MALLOC(dsize);

    else {

	*dworkptr = (doublecomplex *) zuser_malloc(dsize, TAIL, Glu);

	if ( NotDoubleAlign(*dworkptr) ) {

	    old_ptr = *dworkptr;

	    *dworkptr = (doublecomplex*) DoubleAlign(*dworkptr);

	    *dworkptr = (doublecomplex*) ((double*)*dworkptr - 1);

	    extra = (char*)old_ptr - (char*)*dworkptr;

#ifdef DEBUG	    

	    printf("zLUWorkInit: not aligned, extra %d\n", extra);

#endif	    

	    Glu->stack.top2 -= extra;

	    Glu->stack.used += extra;

	}

    }

    if ( ! *dworkptr ) {

	fprintf(stderr, "malloc fails for local dworkptr[].");

	return (isize + dsize + n);

    }

    return 0;

}

/*! \brief Set up pointers for real working arrays.

 */

void

zSetRWork(int m, int panel_size, doublecomplex *dworkptr,

	 doublecomplex **dense, doublecomplex **tempv)

{

    doublecomplex zero = {0.0, 0.0};

    int maxsuper = SUPERLU_MAX( sp_ienv(3), sp_ienv(7) ),

        rowblk   = sp_ienv(4);

    *dense = dworkptr;

    *tempv = *dense + panel_size*m;

    zfill (*dense, m * panel_size, zero);

    zfill (*tempv, NUM_TEMPV(m,panel_size,maxsuper,rowblk), zero);     

}

/*! \brief Free the working storage used by factor routines.

 */

void zLUWorkFree(int *iwork, doublecomplex *dwork, GlobalLU_t *Glu)

{

    if ( Glu->MemModel == SYSTEM ) {

	SUPERLU_FREE (iwork);

	SUPERLU_FREE (dwork);

    } else {

	Glu->stack.used -= (Glu->stack.size - Glu->stack.top2);

	Glu->stack.top2 = Glu->stack.size;

/*	zStackCompress(Glu);  */

    }

    SUPERLU_FREE (Glu->expanders);	

    Glu->expanders = NULL;

}

/*! \brief Expand the data structures for L and U during the factorization.

 * 

 * 

 * Return value:   0 - successful return

 *               > 0 - number of bytes allocated when run out of space

 * 

 */

int

zLUMemXpand(int jcol,

	   int next,          /* number of elements currently in the factors */

	   MemType mem_type,  /* which type of memory to expand  */

	   int *maxlen,       /* modified - maximum length of a data structure */

	   GlobalLU_t *Glu    /* modified - global LU data structures */

	   )

{

    void   *new_mem;

#ifdef DEBUG    

    printf("zLUMemXpand(): jcol %d, next %d, maxlen %d, MemType %d\n",

	   jcol, next, *maxlen, mem_type);

#endif    

    if (mem_type == USUB) 

    	new_mem = zexpand(maxlen, mem_type, next, 1, Glu);

    else

	new_mem = zexpand(maxlen, mem_type, next, 0, Glu);

    if ( !new_mem ) {

	int    nzlmax  = Glu->nzlmax;

	int    nzumax  = Glu->nzumax;

	int    nzlumax = Glu->nzlumax;

    	fprintf(stderr, "Can't expand MemType %d: jcol %d\n", mem_type, jcol);

    	return (zmemory_usage(nzlmax, nzumax, nzlumax, Glu->n) + Glu->n);

    }

    switch ( mem_type ) {

      case LUSUP:

	Glu->lusup   = (doublecomplex *) new_mem;

	Glu->nzlumax = *maxlen;

	break;

      case UCOL:

	Glu->ucol   = (doublecomplex *) new_mem;

	Glu->nzumax = *maxlen;

	break;

      case LSUB:

	Glu->lsub   = (int *) new_mem;

	Glu->nzlmax = *maxlen;

	break;

      case USUB:

	Glu->usub   = (int *) new_mem;

	Glu->nzumax = *maxlen;

	break;

    }

    return 0;

}

void

copy_mem_doublecomplex(int howmany, void *old, void *new)

{

    register int i;

    doublecomplex *dold = old;

    doublecomplex *dnew = new;

    for (i = 0; i < howmany; i++) dnew[i] = dold[i];

}

/*! \brief Expand the existing storage to accommodate more fill-ins.

 */

void

*zexpand (

	 int *prev_len,   /* length used from previous call */

	 MemType type,    /* which part of the memory to expand */

	 int len_to_copy, /* size of the memory to be copied to new store */

	 int keep_prev,   /* = 1: use prev_len;

			     = 0: compute new_len to expand */

	 GlobalLU_t *Glu  /* modified - global LU data structures */

	)

{

    float    EXPAND = 1.5;

    float    alpha;

    void     *new_mem, *old_mem;

    int      new_len, tries, lword, extra, bytes_to_copy;

    ExpHeader *expanders = Glu->expanders; /* Array of 4 types of memory */

    alpha = EXPAND;

    if ( Glu->num_expansions == 0 || keep_prev ) {

        /* First time allocate requested */

        new_len = *prev_len;

    } else {

	new_len = alpha * *prev_len;

    }

    if ( type == LSUB || type == USUB ) lword = sizeof(int);

    else lword = sizeof(doublecomplex);

    if ( Glu->MemModel == SYSTEM ) {

	new_mem = (void *) SUPERLU_MALLOC((size_t)new_len * lword);

	if ( Glu->num_expansions != 0 ) {

	    tries = 0;

	    if ( keep_prev ) {

		if ( !new_mem ) return (NULL);

	    } else {

		while ( !new_mem ) {

		    if ( ++tries > 10 ) return (NULL);

		    alpha = Reduce(alpha);

		    new_len = alpha * *prev_len;

		    new_mem = (void *) SUPERLU_MALLOC((size_t)new_len * lword);

		}

	    }

	    if ( type == LSUB || type == USUB ) {

		copy_mem_int(len_to_copy, expanders[type].mem, new_mem);

	    } else {

		copy_mem_doublecomplex(len_to_copy, expanders[type].mem, new_mem);

	    }

	    SUPERLU_FREE (expanders[type].mem);

	}

	expanders[type].mem = (void *) new_mem;

    } else { /* MemModel == USER */

	if ( Glu->num_expansions == 0 ) {

	    new_mem = zuser_malloc(new_len * lword, HEAD, Glu);

	    if ( NotDoubleAlign(new_mem) &&

		(type == LUSUP || type == UCOL) ) {

		old_mem = new_mem;

		new_mem = (void *)DoubleAlign(new_mem);

		extra = (char*)new_mem - (char*)old_mem;

#ifdef DEBUG		

		printf("expand(): not aligned, extra %d\n", extra);

#endif		

		Glu->stack.top1 += extra;

		Glu->stack.used += extra;

	    }

	    expanders[type].mem = (void *) new_mem;

	} else {

	    tries = 0;

	    extra = (new_len - *prev_len) * lword;

	    if ( keep_prev ) {

		if ( StackFull(extra) ) return (NULL);

	    } else {

		while ( StackFull(extra) ) {

		    if ( ++tries > 10 ) return (NULL);

		    alpha = Reduce(alpha);

		    new_len = alpha * *prev_len;

		    extra = (new_len - *prev_len) * lword;	    

		}

	    }

	    if ( type != USUB ) {

		new_mem = (void*)((char*)expanders[type + 1].mem + extra);

		bytes_to_copy = (char*)Glu->stack.array + Glu->stack.top1

		    - (char*)expanders[type + 1].mem;

		user_bcopy(expanders[type+1].mem, new_mem, bytes_to_copy);

		if ( type < USUB ) {

		    Glu->usub = expanders[USUB].mem =

			(void*)((char*)expanders[USUB].mem + extra);

		}

		if ( type < LSUB ) {

		    Glu->lsub = expanders[LSUB].mem =

			(void*)((char*)expanders[LSUB].mem + extra);

		}

		if ( type < UCOL ) {

		    Glu->ucol = expanders[UCOL].mem =

			(void*)((char*)expanders[UCOL].mem + extra);

		}

		Glu->stack.top1 += extra;

		Glu->stack.used += extra;

		if ( type == UCOL ) {

		    Glu->stack.top1 += extra;   /* Add same amount for USUB */

		    Glu->stack.used += extra;

		}

	    } /* if ... */

	} /* else ... */

    }

    expanders[type].size = new_len;

    *prev_len = new_len;

    if ( Glu->num_expansions ) ++Glu->num_expansions;

    return (void *) expanders[type].mem;

} /* zexpand */

/*! \brief Compress the work[] array to remove fragmentation.

 */

void

zStackCompress(GlobalLU_t *Glu)

{

    register int iword, dword, ndim;

    char    *last, *fragment;

    int      *ifrom, *ito;

    doublecomplex   *dfrom, *dto;

    int      *xlsub, *lsub, *xusub, *usub, *xlusup;

    doublecomplex   *ucol, *lusup;

    iword = sizeof(int);

    dword = sizeof(doublecomplex);

    ndim = Glu->n;

    xlsub  = Glu->xlsub;

    lsub   = Glu->lsub;

    xusub  = Glu->xusub;

    usub   = Glu->usub;

    xlusup = Glu->xlusup;

    ucol   = Glu->ucol;

    lusup  = Glu->lusup;

    dfrom = ucol;

    dto = (doublecomplex *)((char*)lusup + xlusup[ndim] * dword);

    copy_mem_doublecomplex(xusub[ndim], dfrom, dto);

    ucol = dto;

    ifrom = lsub;

    ito = (int *) ((char*)ucol + xusub[ndim] * iword);

    copy_mem_int(xlsub[ndim], ifrom, ito);

    lsub = ito;

    ifrom = usub;

    ito = (int *) ((char*)lsub + xlsub[ndim] * iword);

    copy_mem_int(xusub[ndim], ifrom, ito);

    usub = ito;

    last = (char*)usub + xusub[ndim] * iword;

    fragment = (char*) (((char*)Glu->stack.array + Glu->stack.top1) - last);

    Glu->stack.used -= (long int) fragment;

    Glu->stack.top1 -= (long int) fragment;

    Glu->ucol = ucol;

    Glu->lsub = lsub;

    Glu->usub = usub;

#ifdef DEBUG

    printf("zStackCompress: fragment %d\n", fragment);

    /* for (last = 0; last < ndim; ++last)

	print_lu_col("After compress:", last, 0);*/

#endif    

}

/*! \brief Allocate storage for original matrix A

 */

void

zallocateA(int n, int nnz, doublecomplex **a, int **asub, int **xa)

{

    *a    = (doublecomplex *) doublecomplexMalloc(nnz);

    *asub = (int *) intMalloc(nnz);

    *xa   = (int *) intMalloc(n+1);

}

doublecomplex *doublecomplexMalloc(int n)

{

    doublecomplex *buf;

    buf = (doublecomplex *) SUPERLU_MALLOC((size_t)n * sizeof(doublecomplex)); 

    if ( !buf ) {

	ABORT("SUPERLU_MALLOC failed for buf in doublecomplexMalloc()\n");

    }

    return (buf);

}

doublecomplex *doublecomplexCalloc(int n)

{

    doublecomplex *buf;

    register int i;

    doublecomplex zero = {0.0, 0.0};

    buf = (doublecomplex *) SUPERLU_MALLOC((size_t)n * sizeof(doublecomplex));

    if ( !buf ) {

	ABORT("SUPERLU_MALLOC failed for buf in doublecomplexCalloc()\n");

    }

    for (i = 0; i < n; ++i) buf[i] = zero;

    return (buf);

}

int zmemory_usage(const int nzlmax, const int nzumax, 

		  const int nzlumax, const int n)

{

    register int iword, dword;

    iword   = sizeof(int);

    dword   = sizeof(doublecomplex);

    return (10 * n * iword +

	    nzlmax * iword + nzumax * (iword + dword) + nzlumax * dword);

}