zdotu

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, doublecomplex *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 function 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. INCX must not be zero. Unchanged on exit.
* Y (input): of DIMENSION at least ( 1 + ( m - 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. INCY must not be zero. Unchanged on exit.