1HPL_daxpy(3) HPL Library Functions HPL_daxpy(3)
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6 HPL_daxpy - y := y + alpha * x.
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9 #include "hpl.h"
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11 void HPL_daxpy( const int N, const double ALPHA, const double * X,
12 const int INCX, double * Y, const int INCY );
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15 HPL_daxpy scales the vector x by alpha and adds it to y.
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18 N (local input) const int
19 On entry, N specifies the length of the vectors x and y. N
20 must be at least zero.
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22 ALPHA (local input) const double
23 On entry, ALPHA specifies the scalar alpha. When ALPHA is
24 supplied as zero, then the entries of the incremented array X
25 need not be set on input.
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27 X (local input) const double *
28 On entry, X is an incremented array of dimension at least (
29 1 + ( n - 1 ) * abs( INCX ) ) that contains the vector x.
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31 INCX (local input) const int
32 On entry, INCX specifies the increment for the elements of X.
33 INCX must not be zero.
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35 Y (local input/output) double *
36 On entry, Y is an incremented array of dimension at least (
37 1 + ( n - 1 ) * abs( INCY ) ) that contains the vector y. On
38 exit, the entries of the incremented array Y are updated with
39 the scaled entries of the incremented array X.
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41 INCY (local input) const int
42 On entry, INCY specifies the increment for the elements of Y.
43 INCY must not be zero.
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46 #include "hpl.h"
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48 int main(int argc, char *argv[])
49 {
50 double x[3], y[3];
51 x[0] = 1.0; x[1] = 2.0; x[2] = 3.0;
52 y[0] = 4.0; y[1] = 5.0; y[2] = 6.0;
53 HPL_daxpy( 3, 2.0, x, 1, y, 1 );
54 printf("y=[%f,%f,%f]\n", y[0], y[1], y[2]);
55 exit(0); return(0);
56 }
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59 HPL_dcopy (3), HPL_dscal (3), HPL_dswap (3).
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63HPL 2.2 February 24, 2016 HPL_daxpy(3)