 LAPACK 3.11.0 LAPACK: Linear Algebra PACKage
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## ◆ zdotu()

 complex*16 function zdotu ( integer N, complex*16, dimension(*) ZX, integer INCX, complex*16, dimension(*) ZY, integer INCY )

ZDOTU

Purpose:
``` ZDOTU forms the dot product of two complex vectors
ZDOTU = X^T * Y```
Parameters
 [in] N ``` N is INTEGER number of elements in input vector(s)``` [in] ZX ` ZX is COMPLEX*16 array, dimension ( 1 + ( N - 1 )*abs( INCX ) )` [in] INCX ``` INCX is INTEGER storage spacing between elements of ZX``` [in] ZY ` ZY is COMPLEX*16 array, dimension ( 1 + ( N - 1 )*abs( INCY ) )` [in] INCY ``` INCY is INTEGER storage spacing between elements of ZY```
Further Details:
```     jack dongarra, 3/11/78.
modified 12/3/93, array(1) declarations changed to array(*)```

Definition at line 82 of file zdotu.f.

83*
84* -- Reference BLAS level1 routine --
85* -- Reference BLAS is a software package provided by Univ. of Tennessee, --
86* -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
87*
88* .. Scalar Arguments ..
89 INTEGER INCX,INCY,N
90* ..
91* .. Array Arguments ..
92 COMPLEX*16 ZX(*),ZY(*)
93* ..
94*
95* =====================================================================
96*
97* .. Local Scalars ..
98 COMPLEX*16 ZTEMP
99 INTEGER I,IX,IY
100* ..
101 ztemp = (0.0d0,0.0d0)
102 zdotu = (0.0d0,0.0d0)
103 IF (n.LE.0) RETURN
104 IF (incx.EQ.1 .AND. incy.EQ.1) THEN
105*
106* code for both increments equal to 1
107*
108 DO i = 1,n
109 ztemp = ztemp + zx(i)*zy(i)
110 END DO
111 ELSE
112*
113* code for unequal increments or equal increments
114* not equal to 1
115*
116 ix = 1
117 iy = 1
118 IF (incx.LT.0) ix = (-n+1)*incx + 1
119 IF (incy.LT.0) iy = (-n+1)*incy + 1
120 DO i = 1,n
121 ztemp = ztemp + zx(ix)*zy(iy)
122 ix = ix + incx
123 iy = iy + incy
124 END DO
125 END IF
126 zdotu = ztemp
127 RETURN
128*
129* End of ZDOTU
130*
complex *16 function zdotu(N, ZX, INCX, ZY, INCY)
ZDOTU
Definition: zdotu.f:83
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