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version 1.7, 2011/07/22 07:38:02 version 1.8, 2011/11/21 20:37:08
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   *> \brief \b DSYR2
   *
   *  =========== DOCUMENTATION ===========
   *
   * Online html documentation available at 
   *            http://www.netlib.org/lapack/explore-html/ 
   *
   *  Definition:
   *  ===========
   *
   *       SUBROUTINE DSYR2(UPLO,N,ALPHA,X,INCX,Y,INCY,A,LDA)
   * 
   *       .. Scalar Arguments ..
   *       DOUBLE PRECISION ALPHA
   *       INTEGER INCX,INCY,LDA,N
   *       CHARACTER UPLO
   *       ..
   *       .. Array Arguments ..
   *       DOUBLE PRECISION A(LDA,*),X(*),Y(*)
   *       ..
   *  
   *
   *> \par Purpose:
   *  =============
   *>
   *> \verbatim
   *>
   *> DSYR2  performs the symmetric rank 2 operation
   *>
   *>    A := alpha*x*y**T + alpha*y*x**T + A,
   *>
   *> where alpha is a scalar, x and y are n element vectors and A is an n
   *> by n symmetric matrix.
   *> \endverbatim
   *
   *  Arguments:
   *  ==========
   *
   *> \param[in] UPLO
   *> \verbatim
   *>          UPLO is CHARACTER*1
   *>           On entry, UPLO specifies whether the upper or lower
   *>           triangular part of the array A is to be referenced as
   *>           follows:
   *>
   *>              UPLO = 'U' or 'u'   Only the upper triangular part of A
   *>                                  is to be referenced.
   *>
   *>              UPLO = 'L' or 'l'   Only the lower triangular part of A
   *>                                  is to be referenced.
   *> \endverbatim
   *>
   *> \param[in] N
   *> \verbatim
   *>          N is INTEGER
   *>           On entry, N specifies the order of the matrix A.
   *>           N must be at least zero.
   *> \endverbatim
   *>
   *> \param[in] ALPHA
   *> \verbatim
   *>          ALPHA is DOUBLE PRECISION.
   *>           On entry, ALPHA specifies the scalar alpha.
   *> \endverbatim
   *>
   *> \param[in] X
   *> \verbatim
   *>          X is DOUBLE PRECISION array of dimension at least
   *>           ( 1 + ( n - 1 )*abs( INCX ) ).
   *>           Before entry, the incremented array X must contain the n
   *>           element vector x.
   *> \endverbatim
   *>
   *> \param[in] INCX
   *> \verbatim
   *>          INCX is INTEGER
   *>           On entry, INCX specifies the increment for the elements of
   *>           X. INCX must not be zero.
   *> \endverbatim
   *>
   *> \param[in] Y
   *> \verbatim
   *>          Y is DOUBLE PRECISION array of dimension at least
   *>           ( 1 + ( n - 1 )*abs( INCY ) ).
   *>           Before entry, the incremented array Y must contain the n
   *>           element vector y.
   *> \endverbatim
   *>
   *> \param[in] INCY
   *> \verbatim
   *>          INCY is INTEGER
   *>           On entry, INCY specifies the increment for the elements of
   *>           Y. INCY must not be zero.
   *> \endverbatim
   *>
   *> \param[in,out] A
   *> \verbatim
   *>          A is DOUBLE PRECISION array of DIMENSION ( LDA, n ).
   *>           Before entry with  UPLO = 'U' or 'u', the leading n by n
   *>           upper triangular part of the array A must contain the upper
   *>           triangular part of the symmetric matrix and the strictly
   *>           lower triangular part of A is not referenced. On exit, the
   *>           upper triangular part of the array A is overwritten by the
   *>           upper triangular part of the updated matrix.
   *>           Before entry with UPLO = 'L' or 'l', the leading n by n
   *>           lower triangular part of the array A must contain the lower
   *>           triangular part of the symmetric matrix and the strictly
   *>           upper triangular part of A is not referenced. On exit, the
   *>           lower triangular part of the array A is overwritten by the
   *>           lower triangular part of the updated matrix.
   *> \endverbatim
   *>
   *> \param[in] LDA
   *> \verbatim
   *>          LDA is INTEGER
   *>           On entry, LDA specifies the first dimension of A as declared
   *>           in the calling (sub) program. LDA must be at least
   *>           max( 1, n ).
   *> \endverbatim
   *
   *  Authors:
   *  ========
   *
   *> \author Univ. of Tennessee 
   *> \author Univ. of California Berkeley 
   *> \author Univ. of Colorado Denver 
   *> \author NAG Ltd. 
   *
   *> \date November 2011
   *
   *> \ingroup double_blas_level2
   *
   *> \par Further Details:
   *  =====================
   *>
   *> \verbatim
   *>
   *>  Level 2 Blas routine.
   *>
   *>  -- Written on 22-October-1986.
   *>     Jack Dongarra, Argonne National Lab.
   *>     Jeremy Du Croz, Nag Central Office.
   *>     Sven Hammarling, Nag Central Office.
   *>     Richard Hanson, Sandia National Labs.
   *> \endverbatim
   *>
   *  =====================================================================
       SUBROUTINE DSYR2(UPLO,N,ALPHA,X,INCX,Y,INCY,A,LDA)        SUBROUTINE DSYR2(UPLO,N,ALPHA,X,INCX,Y,INCY,A,LDA)
   *
   *  -- Reference BLAS level2 routine (version 3.4.0) --
   *  -- Reference BLAS is a software package provided by Univ. of Tennessee,    --
   *  -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
   *     November 2011
   *
 *     .. Scalar Arguments ..  *     .. Scalar Arguments ..
       DOUBLE PRECISION ALPHA        DOUBLE PRECISION ALPHA
       INTEGER INCX,INCY,LDA,N        INTEGER INCX,INCY,LDA,N
Line 8 Line 161
       DOUBLE PRECISION A(LDA,*),X(*),Y(*)        DOUBLE PRECISION A(LDA,*),X(*),Y(*)
 *     ..  *     ..
 *  *
 *  Purpose  
 *  =======  
 *  
 *  DSYR2  performs the symmetric rank 2 operation  
 *  
 *     A := alpha*x*y**T + alpha*y*x**T + A,  
 *  
 *  where alpha is a scalar, x and y are n element vectors and A is an n  
 *  by n symmetric matrix.  
 *  
 *  Arguments  
 *  ==========  
 *  
 *  UPLO   - CHARACTER*1.  
 *           On entry, UPLO specifies whether the upper or lower  
 *           triangular part of the array A is to be referenced as  
 *           follows:  
 *  
 *              UPLO = 'U' or 'u'   Only the upper triangular part of A  
 *                                  is to be referenced.  
 *  
 *              UPLO = 'L' or 'l'   Only the lower triangular part of A  
 *                                  is to be referenced.  
 *  
 *           Unchanged on exit.  
 *  
 *  N      - INTEGER.  
 *           On entry, N specifies the order of the matrix A.  
 *           N must be at least zero.  
 *           Unchanged on exit.  
 *  
 *  ALPHA  - DOUBLE PRECISION.  
 *           On entry, ALPHA specifies the scalar alpha.  
 *           Unchanged on exit.  
 *  
 *  X      - DOUBLE PRECISION array of dimension at least  
 *           ( 1 + ( n - 1 )*abs( INCX ) ).  
 *           Before entry, the incremented array X must contain the n  
 *           element vector x.  
 *           Unchanged on exit.  
 *  
 *  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 + ( n - 1 )*abs( INCY ) ).  
 *           Before entry, the incremented array Y must contain the n  
 *           element 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.  
 *  
 *  A      - DOUBLE PRECISION array of DIMENSION ( LDA, n ).  
 *           Before entry with  UPLO = 'U' or 'u', the leading n by n  
 *           upper triangular part of the array A must contain the upper  
 *           triangular part of the symmetric matrix and the strictly  
 *           lower triangular part of A is not referenced. On exit, the  
 *           upper triangular part of the array A is overwritten by the  
 *           upper triangular part of the updated matrix.  
 *           Before entry with UPLO = 'L' or 'l', the leading n by n  
 *           lower triangular part of the array A must contain the lower  
 *           triangular part of the symmetric matrix and the strictly  
 *           upper triangular part of A is not referenced. On exit, the  
 *           lower triangular part of the array A is overwritten by the  
 *           lower triangular part of the updated matrix.  
 *  
 *  LDA    - INTEGER.  
 *           On entry, LDA specifies the first dimension of A as declared  
 *           in the calling (sub) program. LDA must be at least  
 *           max( 1, n ).  
 *           Unchanged on exit.  
 *  
 *  Further Details  
 *  ===============  
 *  
 *  Level 2 Blas routine.  
 *  
 *  -- Written on 22-October-1986.  
 *     Jack Dongarra, Argonne National Lab.  
 *     Jeremy Du Croz, Nag Central Office.  
 *     Sven Hammarling, Nag Central Office.  
 *     Richard Hanson, Sandia National Labs.  
 *  
 *  =====================================================================  *  =====================================================================
 *  *
 *     .. Parameters ..  *     .. Parameters ..
Removed from v.1.7  
changed lines
  Added in v.1.8

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