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HPL_dger(3)		     HPL Library Functions		   HPL_dger(3)

NAME
       HPL_dger	- A := alpha * x * y^T + A.

SYNOPSIS
       #include	"hpl.h"

       void  HPL_dger(	const  enum HPL_ORDER ORDER, const int M, const	int N,
       const double ALPHA, const double	* X, const int INCX, double * Y, const
       int INCY, double	* A, const int LDA );

DESCRIPTION
       HPL_dger	performs the rank 1 operation

	   A :=	alpha *	x * y^T	+ A,

       where  alpha  is	a scalar,  x is	an m-element vector, y is an n-element
       vector and A is an m by n matrix.

ARGUMENTS
       ORDER   (local input)	       const enum HPL_ORDER
	       On entry, ORDER	specifies the storage format of	 the  operands
	       as follows:
		  ORDER	= HplRowMajor,
		  ORDER	= HplColumnMajor.

       M       (local input)	       const int
	       On  entry,   M  specifies  the number of	rows of	 the matrix A.
	       M must be at least zero.

       N       (local input)	       const int
	       On entry, N  specifies the number of columns of the  matrix  A.
	       N must be at least zero.

       ALPHA   (local input)	       const double
	       On  entry,  ALPHA specifies the scalar alpha.   When  ALPHA  is
	       supplied	as zero	then  X	and Y  need not	be set on input.

       X       (local input)	       const double *
	       On entry,  X  is	an incremented array of	dimension  at  least (
	       1 + ( m - 1 ) * abs( INCX ) )  that  contains the vector	x.

       INCX    (local input)	       const int
	       On  entry,  INCX	specifies the increment	for the	elements of X.
	       INCX must not be	zero.

       Y       (local input)	       double *
	       On entry,  Y  is	an incremented array of	dimension  at  least (
	       1 + ( n - 1 ) * abs( INCY ) )  that  contains the vector	y.

       INCY    (local input)	       const int
	       On  entry,  INCY	specifies the increment	for the	elements of Y.
	       INCY must not be	zero.

       A       (local input/output)    double *
	       On entry,  A  points  to	an array of size equal to  or  greater
	       than  LDA  * n.	Before	entry, the leading m by	n part	of the
	       array  A	 must contain the matrix coefficients. On exit,	 A  is
	       overwritten by the updated matrix.

       LDA     (local input)	       const int
	       On  entry,   LDA	 specifies  the	 leading  dimension  of	 A  as
	       declared	 in  the  calling  (sub) program.  LDA	must   be   at
	       least MAX(1,m).

EXAMPLE
       #include	"hpl.h"

       int main(int argc, char *argv[])
       {
	  double a[2*2], x[2], y[2];
	  a[0] = 1.0; a[1] = 2.0; a[2] = 3.0; a[3] = 3.0;
	  x[0] = 2.0; x[1] = 1.0; y[2] = 1.0; y[3] = 2.0;
	  HPL_dger( HplColumnMajor, 2, 2, 2.0, x, 1, y,	1,
		    a, 2 );
	  printf("y=[%f,%f]\n",	y[0], y[1]);
	  exit(0); return(0);
       }

SEE ALSO
       HPL_dgemv (3), HPL_dtrsv	(3).

HPL 2.3			       December	2, 2018			   HPL_dger(3)

NAME | SYNOPSIS | DESCRIPTION | ARGUMENTS | EXAMPLE | SEE ALSO

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