```
```

### NAME

```     zdotu - compute the dot product of two vectors x and y.

```

### SYNOPSIS

```     DOUBLE COMPLEX FUNCTION ZDOTU(N, X, INCX, Y, INCY)

DOUBLE COMPLEX X(*), Y(*)
INTEGER N, INCX, INCY

DOUBLE COMPLEX FUNCTION ZDOTU_64(N, X, INCX, Y, INCY)

DOUBLE COMPLEX X(*), Y(*)
INTEGER*8 N, INCX, INCY

F95 INTERFACE
COMPLEX(8) FUNCTION DOT([N], X, [INCX], Y, [INCY])

COMPLEX(8), DIMENSION(:) :: X, Y
INTEGER :: N, INCX, INCY

COMPLEX(8) FUNCTION DOT_64([N], X, [INCX], Y, [INCY])

COMPLEX(8), DIMENSION(:) :: X, Y
INTEGER(8) :: N, INCX, INCY

C INTERFACE
#include <sunperf.h>

doublecomplex zdotu(int n, doublecomplex *x, int incx, doub-
lecomplex *y, int incy);

doublecomplex zdotu_64(long n, doublecomplex *x, long  incx,
doublecomplex *y, long incy);

```

### PURPOSE

```     zdotu compute the dot product of x and y where x and  y  are
n-vectors.

```

### ARGUMENTS

```     N (input)
On entry, N specifies the number  of  elements  in
the  vector.   If N is not positive then the func-
tion returns the value 0.0.  Unchanged on exit.
X (input)
of DIMENSION at least ( 1 + ( n - 1 )*abs( INCX  )
).  On entry, the incremented array X must contain
the vector x.  Unchanged on exit.

INCX (input)
On entry, INCX specifies  the  increment  for  the
elements of X. Unchanged on exit.

Y (input)
of DIMENSION at least ( 1 + ( n - 1 )*abs( INCY  )
).  On entry, the incremented array Y must contain
the vector y.  Unchanged on exit.

INCY (input)
On entry, INCY specifies  the  increment  for  the
elements of Y. Unchanged on exit.

```