Return to zdotc.f CVS log

Up to [local] / rpl / lapack / blas

Cohérence

    1: *> \brief \b ZDOTC
    2: *
    3: *  =========== DOCUMENTATION ===========
    4: *
    5: * Online html documentation available at 
    6: *            http://www.netlib.org/lapack/explore-html/ 
    7: *
    8: *  Definition:
    9: *  ===========
   10: *
   11: *       COMPLEX*16 FUNCTION ZDOTC(N,ZX,INCX,ZY,INCY)
   12: * 
   13: *       .. Scalar Arguments ..
   14: *       INTEGER INCX,INCY,N
   15: *       ..
   16: *       .. Array Arguments ..
   17: *       COMPLEX*16 ZX(*),ZY(*)
   18: *       ..
   19: *  
   20: *
   21: *> \par Purpose:
   22: *  =============
   23: *>
   24: *> \verbatim
   25: *>
   26: *> ZDOTC forms the dot product of a vector.
   27: *> \endverbatim
   28: *
   29: *  Authors:
   30: *  ========
   31: *
   32: *> \author Univ. of Tennessee 
   33: *> \author Univ. of California Berkeley 
   34: *> \author Univ. of Colorado Denver 
   35: *> \author NAG Ltd. 
   36: *
   37: *> \date November 2011
   38: *
   39: *> \ingroup complex16_blas_level1
   40: *
   41: *> \par Further Details:
   42: *  =====================
   43: *>
   44: *> \verbatim
   45: *>
   46: *>     jack dongarra, 3/11/78.
   47: *>     modified 12/3/93, array(1) declarations changed to array(*)
   48: *> \endverbatim
   49: *>
   50: *  =====================================================================
   51:       COMPLEX*16 FUNCTION ZDOTC(N,ZX,INCX,ZY,INCY)
   52: *
   53: *  -- Reference BLAS level1 routine (version 3.4.0) --
   54: *  -- Reference BLAS is a software package provided by Univ. of Tennessee,    --
   55: *  -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
   56: *     November 2011
   57: *
   58: *     .. Scalar Arguments ..
   59:       INTEGER INCX,INCY,N
   60: *     ..
   61: *     .. Array Arguments ..
   62:       COMPLEX*16 ZX(*),ZY(*)
   63: *     ..
   64: *
   65: *  =====================================================================
   66: *
   67: *     .. Local Scalars ..
   68:       COMPLEX*16 ZTEMP
   69:       INTEGER I,IX,IY
   70: *     ..
   71: *     .. Intrinsic Functions ..
   72:       INTRINSIC DCONJG
   73: *     ..
   74:       ZTEMP = (0.0d0,0.0d0)
   75:       ZDOTC = (0.0d0,0.0d0)
   76:       IF (N.LE.0) RETURN
   77:       IF (INCX.EQ.1 .AND. INCY.EQ.1) THEN
   78: *
   79: *        code for both increments equal to 1
   80: *
   81:          DO I = 1,N
   82:             ZTEMP = ZTEMP + DCONJG(ZX(I))*ZY(I)
   83:          END DO
   84:       ELSE
   85: *
   86: *        code for unequal increments or equal increments
   87: *          not equal to 1
   88: *
   89:          IX = 1
   90:          IY = 1
   91:          IF (INCX.LT.0) IX = (-N+1)*INCX + 1
   92:          IF (INCY.LT.0) IY = (-N+1)*INCY + 1
   93:          DO I = 1,N
   94:             ZTEMP = ZTEMP + DCONJG(ZX(IX))*ZY(IY)
   95:             IX = IX + INCX
   96:             IY = IY + INCY
   97:          END DO
   98:       END IF
   99:       ZDOTC = ZTEMP
  100:       RETURN
  101:       END