csp_blas2.c

来自「SuperLU is a general purpose library for」· C语言 代码 · 共 574 行 · 第 1/2 页

                /* 1 c_div costs 10 flops */
		solve_ops += 4 * nsupc * (nsupc + 1) + 10 * nsupc;

		if ( nsupc == 1 ) {
		    c_div(&x[fsupc], &x[fsupc], &Lval[luptr]);
		} else {
#ifdef _CRAY
                    ftcs1 = _cptofcd("U", strlen("U"));
                    ftcs2 = _cptofcd("T", strlen("T"));
                    ftcs3 = _cptofcd("N", strlen("N"));
		    CTRSV( ftcs1, ftcs2, ftcs3, &nsupc, &Lval[luptr], &nsupr,
			    &x[fsupc], &incx);
#else
		    ctrsv_("U", "T", "N", &nsupc, &Lval[luptr], &nsupr,
			    &x[fsupc], &incx);
#endif
		}
	    } /* for k ... */
	}
    } else { /* Form x := conj(inv(A'))*x */
	
	if ( lsame_(uplo, "L") ) {
	    /* Form x := conj(inv(L'))*x */
    	    if ( L->nrow == 0 ) return 0; /* Quick return */
	    
	    for (k = Lstore->nsuper; k >= 0; --k) {
	    	fsupc = L_FST_SUPC(k);
	    	istart = L_SUB_START(fsupc);
	    	nsupr = L_SUB_START(fsupc+1) - istart;
	    	nsupc = L_FST_SUPC(k+1) - fsupc;
	    	luptr = L_NZ_START(fsupc);

		solve_ops += 8 * (nsupr - nsupc) * nsupc;

		for (jcol = fsupc; jcol < L_FST_SUPC(k+1); jcol++) {
		    iptr = istart + nsupc;
		    for (i = L_NZ_START(jcol) + nsupc; 
				i < L_NZ_START(jcol+1); i++) {
			irow = L_SUB(iptr);
                        cc_conj(&temp, &Lval[i]);
			cc_mult(&comp_zero, &x[irow], &temp);
		    	c_sub(&x[jcol], &x[jcol], &comp_zero);
			iptr++;
		    }
 		}
 		
 		if ( nsupc > 1 ) {
		    solve_ops += 4 * nsupc * (nsupc - 1);
#ifdef _CRAY
                    ftcs1 = _cptofcd("L", strlen("L"));
                    ftcs2 = _cptofcd(trans, strlen("T"));
                    ftcs3 = _cptofcd("U", strlen("U"));
		    CTRSV(ftcs1, ftcs2, ftcs3, &nsupc, &Lval[luptr], &nsupr,
			&x[fsupc], &incx);
#else
                    ctrsv_("L", trans, "U", &nsupc, &Lval[luptr], &nsupr,
                           &x[fsupc], &incx);
#endif
		}
	    }
	} else {
	    /* Form x := conj(inv(U'))*x */
	    if ( U->nrow == 0 ) return 0; /* Quick return */
	    
	    for (k = 0; k <= Lstore->nsuper; k++) {
	    	fsupc = L_FST_SUPC(k);
	    	nsupr = L_SUB_START(fsupc+1) - L_SUB_START(fsupc);
	    	nsupc = L_FST_SUPC(k+1) - fsupc;
	    	luptr = L_NZ_START(fsupc);

		for (jcol = fsupc; jcol < L_FST_SUPC(k+1); jcol++) {
		    solve_ops += 8*(U_NZ_START(jcol+1) - U_NZ_START(jcol));
		    for (i = U_NZ_START(jcol); i < U_NZ_START(jcol+1); i++) {
			irow = U_SUB(i);
                        cc_conj(&temp, &Uval[i]);
			cc_mult(&comp_zero, &x[irow], &temp);
		    	c_sub(&x[jcol], &x[jcol], &comp_zero);
		    }
		}

                /* 1 c_div costs 10 flops */
		solve_ops += 4 * nsupc * (nsupc + 1) + 10 * nsupc;
 
		if ( nsupc == 1 ) {
                    cc_conj(&temp, &Lval[luptr]);
		    c_div(&x[fsupc], &x[fsupc], &temp);
		} else {
#ifdef _CRAY
                    ftcs1 = _cptofcd("U", strlen("U"));
                    ftcs2 = _cptofcd(trans, strlen("T"));
                    ftcs3 = _cptofcd("N", strlen("N"));
		    CTRSV( ftcs1, ftcs2, ftcs3, &nsupc, &Lval[luptr], &nsupr,
			    &x[fsupc], &incx);
#else
                    ctrsv_("U", trans, "N", &nsupc, &Lval[luptr], &nsupr,
                               &x[fsupc], &incx);
#endif
  		}
  	    } /* for k ... */
  	}
    }

    stat->ops[SOLVE] += solve_ops;
    SUPERLU_FREE(work);
    return 0;
}



/*! \brief Performs one of the matrix-vector operations y := alpha*A*x + beta*y,   or   y := alpha*A'*x + beta*y
 *
 * <pre>  
 *   Purpose   
 *   =======   
 *
 *   sp_cgemv()  performs one of the matrix-vector operations   
 *      y := alpha*A*x + beta*y,   or   y := alpha*A'*x + beta*y,   
 *   where alpha and beta are scalars, x and y are vectors and A is a
 *   sparse A->nrow by A->ncol matrix.   
 *
 *   Parameters   
 *   ==========   
 *
 *   TRANS  - (input) char*
 *            On entry, TRANS specifies the operation to be performed as   
 *            follows:   
 *               TRANS = 'N' or 'n'   y := alpha*A*x + beta*y.   
 *               TRANS = 'T' or 't'   y := alpha*A'*x + beta*y.   
 *               TRANS = 'C' or 'c'   y := alpha*A'*x + beta*y.   
 *
 *   ALPHA  - (input) complex
 *            On entry, ALPHA specifies the scalar alpha.   
 *
 *   A      - (input) SuperMatrix*
 *            Before entry, the leading m by n part of the array A must   
 *            contain the matrix of coefficients.   
 *
 *   X      - (input) complex*, array of DIMENSION at least   
 *            ( 1 + ( n - 1 )*abs( INCX ) ) when TRANS = 'N' or 'n'   
 *           and at least   
 *            ( 1 + ( m - 1 )*abs( INCX ) ) otherwise.   
 *            Before entry, the incremented array X must contain the   
 *            vector x.   
 * 
 *   INCX   - (input) int
 *            On entry, INCX specifies the increment for the elements of   
 *            X. INCX must not be zero.   
 *
 *   BETA   - (input) complex
 *            On entry, BETA specifies the scalar beta. When BETA is   
 *            supplied as zero then Y need not be set on input.   
 *
 *   Y      - (output) complex*,  array of DIMENSION at least   
 *            ( 1 + ( m - 1 )*abs( INCY ) ) when TRANS = 'N' or 'n'   
 *            and at least   
 *            ( 1 + ( n - 1 )*abs( INCY ) ) otherwise.   
 *            Before entry with BETA non-zero, the incremented array Y   
 *            must contain the vector y. On exit, Y is overwritten by the 
 *            updated vector y.
 *	      
 *   INCY   - (input) int
 *            On entry, INCY specifies the increment for the elements of   
 *            Y. INCY must not be zero.   
 *
 *    ==== Sparse Level 2 Blas routine.   
 * </pre>
*/
int
sp_cgemv(char *trans, complex alpha, SuperMatrix *A, complex *x, 
	 int incx, complex beta, complex *y, int incy)
{

    /* Local variables */
    NCformat *Astore;
    complex   *Aval;
    int info;
    complex temp, temp1;
    int lenx, leny, i, j, irow;
    int iy, jx, jy, kx, ky;
    int notran;
    complex comp_zero = {0.0, 0.0};
    complex comp_one = {1.0, 0.0};

    notran = lsame_(trans, "N");
    Astore = A->Store;
    Aval = Astore->nzval;
    
    /* Test the input parameters */
    info = 0;
    if ( !notran && !lsame_(trans, "T") && !lsame_(trans, "C")) info = 1;
    else if ( A->nrow < 0 || A->ncol < 0 ) info = 3;
    else if (incx == 0) info = 5;
    else if (incy == 0)	info = 8;
    if (info != 0) {
	xerbla_("sp_cgemv ", &info);
	return 0;
    }

    /* Quick return if possible. */
    if (A->nrow == 0 || A->ncol == 0 || 
	c_eq(&alpha, &comp_zero) && 
	c_eq(&beta, &comp_one))
	return 0;


    /* Set  LENX  and  LENY, the lengths of the vectors x and y, and set 
       up the start points in  X  and  Y. */
    if (lsame_(trans, "N")) {
	lenx = A->ncol;
	leny = A->nrow;
    } else {
	lenx = A->nrow;
	leny = A->ncol;
    }
    if (incx > 0) kx = 0;
    else kx =  - (lenx - 1) * incx;
    if (incy > 0) ky = 0;
    else ky =  - (leny - 1) * incy;

    /* Start the operations. In this version the elements of A are   
       accessed sequentially with one pass through A. */
    /* First form  y := beta*y. */
    if ( !c_eq(&beta, &comp_one) ) {
	if (incy == 1) {
	    if ( c_eq(&beta, &comp_zero) )
		for (i = 0; i < leny; ++i) y[i] = comp_zero;
	    else
		for (i = 0; i < leny; ++i) 
		  cc_mult(&y[i], &beta, &y[i]);
	} else {
	    iy = ky;
	    if ( c_eq(&beta, &comp_zero) )
		for (i = 0; i < leny; ++i) {
		    y[iy] = comp_zero;
		    iy += incy;
		}
	    else
		for (i = 0; i < leny; ++i) {
		    cc_mult(&y[iy], &beta, &y[iy]);
		    iy += incy;
		}
	}
    }
    
    if ( c_eq(&alpha, &comp_zero) ) return 0;

    if ( notran ) {
	/* Form  y := alpha*A*x + y. */
	jx = kx;
	if (incy == 1) {
	    for (j = 0; j < A->ncol; ++j) {
		if ( !c_eq(&x[jx], &comp_zero) ) {
		    cc_mult(&temp, &alpha, &x[jx]);
		    for (i = Astore->colptr[j]; i < Astore->colptr[j+1]; ++i) {
			irow = Astore->rowind[i];
			cc_mult(&temp1, &temp,  &Aval[i]);
			c_add(&y[irow], &y[irow], &temp1);
		    }
		}
		jx += incx;
	    }
	} else {
	    ABORT("Not implemented.");
	}
    } else {
	/* Form  y := alpha*A'*x + y. */
	jy = ky;
	if (incx == 1) {
	    for (j = 0; j < A->ncol; ++j) {
		temp = comp_zero;
		for (i = Astore->colptr[j]; i < Astore->colptr[j+1]; ++i) {
		    irow = Astore->rowind[i];
		    cc_mult(&temp1, &Aval[i], &x[irow]);
		    c_add(&temp, &temp, &temp1);
		}
		cc_mult(&temp1, &alpha, &temp);
		c_add(&y[jy], &y[jy], &temp1);
		jy += incy;
	    }
	} else {
	    ABORT("Not implemented.");
	}
    }
    return 0;    
} /* sp_cgemv */