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path: root/BLAS/SRC/zdotu.f
 ```1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 ``` ``````*> \brief \b ZDOTU * * =========== DOCUMENTATION =========== * * Online html documentation available at * http://www.netlib.org/lapack/explore-html/ * * Definition: * =========== * * COMPLEX*16 FUNCTION ZDOTU(N,ZX,INCX,ZY,INCY) * * .. Scalar Arguments .. * INTEGER INCX,INCY,N * .. * .. Array Arguments .. * COMPLEX*16 ZX(*),ZY(*) * .. * * *> \par Purpose: * ============= *> *> \verbatim *> *> ZDOTU forms the dot product of two complex vectors *> ZDOTU = X^T * Y *> *> \endverbatim * * Arguments: * ========== * *> \param[in] N *> \verbatim *> N is INTEGER *> number of elements in input vector(s) *> \endverbatim *> *> \param[in] ZX *> \verbatim *> ZX is REAL array, dimension ( 1 + ( N - 1 )*abs( INCX ) ) *> \endverbatim *> *> \param[in] INCX *> \verbatim *> INCX is INTEGER *> storage spacing between elements of ZX *> \endverbatim *> *> \param[in] ZY *> \verbatim *> ZY is REAL array, dimension ( 1 + ( N - 1 )*abs( INCY ) ) *> \endverbatim *> *> \param[in] INCY *> \verbatim *> INCY is INTEGER *> storage spacing between elements of ZY *> \endverbatim * * Authors: * ======== * *> \author Univ. of Tennessee *> \author Univ. of California Berkeley *> \author Univ. of Colorado Denver *> \author NAG Ltd. * *> \date December 2016 * *> \ingroup complex16_blas_level1 * *> \par Further Details: * ===================== *> *> \verbatim *> *> jack dongarra, 3/11/78. *> modified 12/3/93, array(1) declarations changed to array(*) *> \endverbatim *> * ===================================================================== COMPLEX*16 FUNCTION ZDOTU(N,ZX,INCX,ZY,INCY) * * -- Reference BLAS level1 routine (version 3.7.0) -- * -- Reference BLAS is a software package provided by Univ. of Tennessee, -- * -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..-- * December 2016 * * .. Scalar Arguments .. INTEGER INCX,INCY,N * .. * .. Array Arguments .. COMPLEX*16 ZX(*),ZY(*) * .. * * ===================================================================== * * .. Local Scalars .. COMPLEX*16 ZTEMP INTEGER I,IX,IY * .. ZTEMP = (0.0d0,0.0d0) ZDOTU = (0.0d0,0.0d0) IF (N.LE.0) RETURN IF (INCX.EQ.1 .AND. INCY.EQ.1) THEN * * code for both increments equal to 1 * DO I = 1,N ZTEMP = ZTEMP + ZX(I)*ZY(I) END DO ELSE * * code for unequal increments or equal increments * not equal to 1 * IX = 1 IY = 1 IF (INCX.LT.0) IX = (-N+1)*INCX + 1 IF (INCY.LT.0) IY = (-N+1)*INCY + 1 DO I = 1,N ZTEMP = ZTEMP + ZX(IX)*ZY(IY) IX = IX + INCX IY = IY + INCY END DO END IF ZDOTU = ZTEMP RETURN END ``````