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Annotation of rpl/lapack/blas/zdscal.f, revision 1.15

1.8       bertrand    1: *> \brief \b ZDSCAL
                      2: *
                      3: *  =========== DOCUMENTATION ===========
                      4: *
1.13      bertrand    5: * Online html documentation available at
                      6: *            http://www.netlib.org/lapack/explore-html/
1.8       bertrand    7: *
                      8: *  Definition:
                      9: *  ===========
                     10: *
                     11: *       SUBROUTINE ZDSCAL(N,DA,ZX,INCX)
1.13      bertrand   12: *
1.8       bertrand   13: *       .. Scalar Arguments ..
                     14: *       DOUBLE PRECISION DA
                     15: *       INTEGER INCX,N
                     16: *       ..
                     17: *       .. Array Arguments ..
                     18: *       COMPLEX*16 ZX(*)
                     19: *       ..
1.13      bertrand   20: *
1.8       bertrand   21: *
                     22: *> \par Purpose:
                     23: *  =============
                     24: *>
                     25: *> \verbatim
                     26: *>
                     27: *>    ZDSCAL scales a vector by a constant.
                     28: *> \endverbatim
                     29: *
1.14      bertrand   30: *  Arguments:
                     31: *  ==========
                     32: *
                     33: *> \param[in] N
                     34: *> \verbatim
                     35: *>          N is INTEGER
                     36: *>         number of elements in input vector(s)
                     37: *> \endverbatim
                     38: *>
                     39: *> \param[in] DA
                     40: *> \verbatim
                     41: *>          DA is DOUBLE PRECISION
                     42: *>           On entry, DA specifies the scalar alpha.
                     43: *> \endverbatim
                     44: *>
                     45: *> \param[in,out] ZX
                     46: *> \verbatim
                     47: *>          ZX is COMPLEX*16 array, dimension ( 1 + ( N - 1 )*abs( INCX ) )
                     48: *> \endverbatim
                     49: *>
                     50: *> \param[in] INCX
                     51: *> \verbatim
                     52: *>          INCX is INTEGER
                     53: *>         storage spacing between elements of ZX
                     54: *> \endverbatim
                     55: *
1.8       bertrand   56: *  Authors:
                     57: *  ========
                     58: *
1.13      bertrand   59: *> \author Univ. of Tennessee
                     60: *> \author Univ. of California Berkeley
                     61: *> \author Univ. of Colorado Denver
                     62: *> \author NAG Ltd.
1.8       bertrand   63: *
1.14      bertrand   64: *> \date November 2017
1.8       bertrand   65: *
                     66: *> \ingroup complex16_blas_level1
                     67: *
                     68: *> \par Further Details:
                     69: *  =====================
                     70: *>
                     71: *> \verbatim
                     72: *>
                     73: *>     jack dongarra, 3/11/78.
                     74: *>     modified 3/93 to return if incx .le. 0.
                     75: *>     modified 12/3/93, array(1) declarations changed to array(*)
                     76: *> \endverbatim
                     77: *>
                     78: *  =====================================================================
1.1       bertrand   79:       SUBROUTINE ZDSCAL(N,DA,ZX,INCX)
1.8       bertrand   80: *
1.14      bertrand   81: *  -- Reference BLAS level1 routine (version 3.8.0) --
1.8       bertrand   82: *  -- Reference BLAS is a software package provided by Univ. of Tennessee,    --
                     83: *  -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
1.14      bertrand   84: *     November 2017
1.8       bertrand   85: *
1.1       bertrand   86: *     .. Scalar Arguments ..
                     87:       DOUBLE PRECISION DA
                     88:       INTEGER INCX,N
                     89: *     ..
                     90: *     .. Array Arguments ..
1.8       bertrand   91:       COMPLEX*16 ZX(*)
1.1       bertrand   92: *     ..
                     93: *
                     94: *  =====================================================================
                     95: *
                     96: *     .. Local Scalars ..
1.7       bertrand   97:       INTEGER I,NINCX
1.1       bertrand   98: *     ..
                     99: *     .. Intrinsic Functions ..
                    100:       INTRINSIC DCMPLX
                    101: *     ..
                    102:       IF (N.LE.0 .OR. INCX.LE.0) RETURN
1.7       bertrand  103:       IF (INCX.EQ.1) THEN
1.1       bertrand  104: *
1.7       bertrand  105: *        code for increment equal to 1
1.1       bertrand  106: *
1.7       bertrand  107:          DO I = 1,N
                    108:             ZX(I) = DCMPLX(DA,0.0d0)*ZX(I)
                    109:          END DO
                    110:       ELSE
1.1       bertrand  111: *
1.7       bertrand  112: *        code for increment not equal to 1
1.1       bertrand  113: *
1.7       bertrand  114:          NINCX = N*INCX
                    115:          DO I = 1,NINCX,INCX
                    116:             ZX(I) = DCMPLX(DA,0.0d0)*ZX(I)
                    117:          END DO
                    118:       END IF
1.1       bertrand  119:       RETURN
                    120:       END