--- rpl/lapack/blas/dscal.f 2011/07/22 07:38:01 1.7 +++ rpl/lapack/blas/dscal.f 2023/08/07 08:38:43 1.16 @@ -1,4 +1,86 @@ +*> \brief \b DSCAL +* +* =========== DOCUMENTATION =========== +* +* Online html documentation available at +* http://www.netlib.org/lapack/explore-html/ +* +* Definition: +* =========== +* +* SUBROUTINE DSCAL(N,DA,DX,INCX) +* +* .. Scalar Arguments .. +* DOUBLE PRECISION DA +* INTEGER INCX,N +* .. +* .. Array Arguments .. +* DOUBLE PRECISION DX(*) +* .. +* +* +*> \par Purpose: +* ============= +*> +*> \verbatim +*> +*> DSCAL scales a vector by a constant. +*> uses unrolled loops for increment equal to 1. +*> \endverbatim +* +* Arguments: +* ========== +* +*> \param[in] N +*> \verbatim +*> N is INTEGER +*> number of elements in input vector(s) +*> \endverbatim +*> +*> \param[in] DA +*> \verbatim +*> DA is DOUBLE PRECISION +*> On entry, DA specifies the scalar alpha. +*> \endverbatim +*> +*> \param[in,out] DX +*> \verbatim +*> DX is DOUBLE PRECISION array, dimension ( 1 + ( N - 1 )*abs( INCX ) ) +*> \endverbatim +*> +*> \param[in] INCX +*> \verbatim +*> INCX is INTEGER +*> storage spacing between elements of DX +*> \endverbatim +* +* Authors: +* ======== +* +*> \author Univ. of Tennessee +*> \author Univ. of California Berkeley +*> \author Univ. of Colorado Denver +*> \author NAG Ltd. +* +*> \ingroup double_blas_level1 +* +*> \par Further Details: +* ===================== +*> +*> \verbatim +*> +*> jack dongarra, linpack, 3/11/78. +*> modified 3/93 to return if incx .le. 0. +*> modified 12/3/93, array(1) declarations changed to array(*) +*> \endverbatim +*> +* ===================================================================== SUBROUTINE DSCAL(N,DA,DX,INCX) +* +* -- Reference BLAS level1 routine -- +* -- Reference BLAS is a software package provided by Univ. of Tennessee, -- +* -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..-- +* * .. Scalar Arguments .. DOUBLE PRECISION DA INTEGER INCX,N @@ -7,28 +89,18 @@ DOUBLE PRECISION DX(*) * .. * -* Purpose -* ======= -* -* DSCAL scales a vector by a constant. -* uses unrolled loops for increment equal to one. -* -* Further Details -* =============== -* -* jack dongarra, linpack, 3/11/78. -* modified 3/93 to return if incx .le. 0. -* modified 12/3/93, array(1) declarations changed to array(*) -* * ===================================================================== * * .. Local Scalars .. INTEGER I,M,MP1,NINCX +* .. Parameters .. + DOUBLE PRECISION ONE + PARAMETER (ONE=1.0D+0) * .. * .. Intrinsic Functions .. INTRINSIC MOD * .. - IF (N.LE.0 .OR. INCX.LE.0) RETURN + IF (N.LE.0 .OR. INCX.LE.0 .OR. DA.EQ.ONE) RETURN IF (INCX.EQ.1) THEN * * code for increment equal to 1 @@ -61,4 +133,7 @@ END DO END IF RETURN +* +* End of DSCAL +* END