ddot
ddot - compute the dot product of two vectors x and y.
DOUBLE PRECISION FUNCTION DDOT( N, X, INCX, Y, INCY)
INTEGER N, INCX, INCY
DOUBLE PRECISION X(*), Y(*)
DOUBLE PRECISION FUNCTION DDOT_64( N, X, INCX, Y, INCY)
INTEGER*8 N, INCX, INCY
DOUBLE PRECISION X(*), Y(*)
REAL(8) FUNCTION DOT( [N], X, [INCX], Y, [INCY])
INTEGER :: N, INCX, INCY
REAL(8), DIMENSION(:) :: X, Y
REAL(8) FUNCTION DOT_64( [N], X, [INCX], Y, [INCY])
INTEGER(8) :: N, INCX, INCY
REAL(8), DIMENSION(:) :: X, Y
#include <sunperf.h>
double ddot(int n, double *x, int incx, double *y, int incy);
double ddot_64(long n, double *x, long incx, double *y, long incy);
ddot compute the dot product of x and y where x and y are n-vectors.
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* N (input)
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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.
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* X (input)
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( 1 + ( n - 1 )*abs( INCX ) ).
On entry, the incremented array X must contain the
vector x. Unchanged on exit.
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* INCX (input)
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On entry, INCX specifies the increment for the elements of
X. INCX must not be zero.
Unchanged on exit.
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* Y (input)
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( 1 + ( m - 1 )*abs( INCY ) ).
On entry, the incremented array Y must contain the
vector y.
Unchanged on exit.
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* INCY (input)
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On entry, INCY specifies the increment for the elements of
Y. INCY must not be zero.
Unchanged on exit.