Centre Blaise Pascal » HPL sur GPU

.TH HPL_daxpy 3 "September 10, 2008" "HPL 2.0" "HPL Library Functions"

.SH NAME

HPL_daxpy \- y := y + alpha * x.

.SH SYNOPSIS

\fB\&#include "hpl.h"\fR

\fB\&void\fR

\fB\&HPL_daxpy(\fR

\fB\&const int\fR

\fI\&N\fR,

\fB\&const double\fR

\fI\&ALPHA\fR,

\fB\&const double *\fR

\fI\&X\fR,

\fB\&const int\fR

\fI\&INCX\fR,

\fB\&double *\fR

\fI\&Y\fR,

\fB\&const int\fR

\fI\&INCY\fR

\fB\&);\fR

.SH DESCRIPTION

\fB\&HPL_daxpy\fR

scales the vector x by alpha and adds it to y.

.SH ARGUMENTS

.TP 8

N       (local input)           const int

On entry, N specifies the length of the vectors  x  and  y. N

must be at least zero.

.TP 8

ALPHA   (local input)           const double

On entry, ALPHA specifies the scalar alpha.   When  ALPHA  is

supplied as zero, then the entries of the incremented array X

need not be set on input.

.TP 8

X       (local input)           const double *

On entry,  X  is an incremented array of dimension  at  least

( 1 + ( n - 1 ) * abs( INCX ) )  that  contains the vector x.

.TP 8

INCX    (local input)           const int

On entry, INCX specifies the increment for the elements of X.

INCX must not be zero.

.TP 8

Y       (local input/output)    double *

On entry,  Y  is an incremented array of dimension  at  least

( 1 + ( n - 1 ) * abs( INCY ) )  that  contains the vector y.

On exit, the entries of the incremented array  Y  are updated

with the scaled entries of the incremented array X.

.TP 8

INCY    (local input)           const int

On entry, INCY specifies the increment for the elements of Y.

INCY must not be zero.

.SH EXAMPLE

\fI\&#include "hpl.h"\fR

int main(int argc, char *argv[])

.br

{

.br

   double x[3], y[3];

.br

   x[0] = 1.0; x[1] = 2.0; x[2] = 3.0;

.br

   y[0] = 4.0; y[1] = 5.0; y[2] = 6.0;

.br

   HPL_daxpy( 3, 2.0, x, 1, y, 1 );

.br

   printf("y=[%f,%f,%f]\en", y[0], y[1], y[2]);

.br

   exit(0); return(0);

.br

}

.SH SEE ALSO

.BR HPL_dcopy \ (3),

.BR HPL_dscal \ (3),

.BR HPL_dswap \ (3).