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*> \brief \b XLAENV
*
* =========== DOCUMENTATION ===========
*
* Online html documentation available at
* http://www.netlib.org/lapack/explore-html/
*
* Definition:
* ===========
*
* SUBROUTINE XLAENV( ISPEC, NVALUE )
*
* .. Scalar Arguments ..
* INTEGER ISPEC, NVALUE
* ..
*
*
*> \par Purpose:
* =============
*>
*> \verbatim
*>
*> XLAENV sets certain machine- and problem-dependent quantities
*> which will later be retrieved by ILAENV.
*> \endverbatim
*
* Arguments:
* ==========
*
*> \param[in] ISPEC
*> \verbatim
*> ISPEC is INTEGER
*> Specifies the parameter to be set in the COMMON array IPARMS.
*> = 1: the optimal blocksize; if this value is 1, an unblocked
*> algorithm will give the best performance.
*> = 2: the minimum block size for which the block routine
*> should be used; if the usable block size is less than
*> this value, an unblocked routine should be used.
*> = 3: the crossover point (in a block routine, for N less
*> than this value, an unblocked routine should be used)
*> = 4: the number of shifts, used in the nonsymmetric
*> eigenvalue routines
*> = 5: the minimum column dimension for blocking to be used;
*> rectangular blocks must have dimension at least k by m,
*> where k is given by ILAENV(2,...) and m by ILAENV(5,...)
*> = 6: the crossover point for the SVD (when reducing an m by n
*> matrix to bidiagonal form, if max(m,n)/min(m,n) exceeds
*> this value, a QR factorization is used first to reduce
*> the matrix to a triangular form)
*> = 7: the number of processors
*> = 8: another crossover point, for the multishift QR and QZ
*> methods for nonsymmetric eigenvalue problems.
*> = 9: maximum size of the subproblems at the bottom of the
*> computation tree in the divide-and-conquer algorithm
*> (used by xGELSD and xGESDD)
*> =10: ieee NaN arithmetic can be trusted not to trap
*> =11: infinity arithmetic can be trusted not to trap
*> 12 <= ISPEC <= 16:
*> xHSEQR or one of its subroutines,
*> see IPARMQ for detailed explanation
*> \endverbatim
*>
*> \param[in] NVALUE
*> \verbatim
*> NVALUE is INTEGER
*> The value of the parameter specified by ISPEC.
*> \endverbatim
*
* Authors:
* ========
*
*> \author Univ. of Tennessee
*> \author Univ. of California Berkeley
*> \author Univ. of Colorado Denver
*> \author NAG Ltd.
*
*> \date November 2011
*
*> \ingroup aux_eig
*
* =====================================================================
SUBROUTINE XLAENV( ISPEC, NVALUE )
*
* -- LAPACK test routine (version 3.4.0) --
* -- LAPACK is a software package provided by Univ. of Tennessee, --
* -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
* November 2011
*
* .. Scalar Arguments ..
INTEGER ISPEC, NVALUE
* ..
*
* =====================================================================
*
* .. Arrays in Common ..
INTEGER IPARMS( 100 )
* ..
* .. Common blocks ..
COMMON / CLAENV / IPARMS
* ..
* .. Save statement ..
SAVE / CLAENV /
* ..
* .. Executable Statements ..
*
IF( ISPEC.GE.1 .AND. ISPEC.LE.16 ) THEN
IPARMS( ISPEC ) = NVALUE
END IF
*
RETURN
*
* End of XLAENV
*
END
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