NAME

ddot - Compute the dot product of two vectors x and y. 

SYNOPSIS

DOUBLE PRECISION FUNCTION DDOT (N, X, INCY, Y, INCY )

INTEGER INCX, INCY, N

DOUBLE PRECISION    X( ∗ ), Y( ∗ )

#include <sunperf.h>

double ddot(int n, double ∗dx, int incx, double ∗dy, int incy) ;

PURPOSE

DDOT - Compute the dot product of x and y where x and y are n-vectors. 
 

PARAMETERS

N - INTEGER. 
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 - DOUBLE PRECISION array of DIMENSION at least
( 1 + ( n - 1 )∗abs( INCX ) ). On entry, the incremented array X must contain the vector x.  On exit, the y vector.

INCX - INTEGER. 
On entry, INCX specifies the increment for the elements of X. INCX must not be zero. Unchanged on exit.

Y - DOUBLE PRECISION array of DIMENSION at least
( 1 + ( m - 1 )∗abs( INCY ) ). On entry, the incremented array Y must contain the vector y. Unchanged on exit.

INCY - INTEGER. 
On entry, INCY specifies the increment for the elements of Y. INCY must not be zero. Unchanged on exit.

SunOS 5.0  —  Last change: 10 Dec 1998