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zlaset.f
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*> \brief \b ZLASET initializes the off-diagonal elements and the diagonal elements of a matrix to given values.
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*
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* =========== DOCUMENTATION ===========
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*
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* Online html documentation available at
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* http://www.netlib.org/lapack/explore-html/
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*
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*> \htmlonly
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*> Download ZLASET + dependencies
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*> <a href="http://www.netlib.org/cgi-bin/netlibfiles.tgz?format=tgz&filename=/lapack/lapack_routine/zlaset.f">
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*> [TGZ]</a>
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*> <a href="http://www.netlib.org/cgi-bin/netlibfiles.zip?format=zip&filename=/lapack/lapack_routine/zlaset.f">
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*> [ZIP]</a>
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*> <a href="http://www.netlib.org/cgi-bin/netlibfiles.txt?format=txt&filename=/lapack/lapack_routine/zlaset.f">
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*> [TXT]</a>
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*> \endhtmlonly
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*
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* Definition:
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* ===========
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*
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* SUBROUTINE ZLASET( UPLO, M, N, ALPHA, BETA, A, LDA )
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*
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* .. Scalar Arguments ..
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* CHARACTER UPLO
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* INTEGER LDA, M, N
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* COMPLEX*16 ALPHA, BETA
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* ..
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* .. Array Arguments ..
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* COMPLEX*16 A( LDA, * )
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* ..
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*
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*
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*> \par Purpose:
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* =============
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*>
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*> \verbatim
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*>
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*> ZLASET initializes a 2-D array A to BETA on the diagonal and
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*> ALPHA on the offdiagonals.
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*> \endverbatim
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*
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* Arguments:
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* ==========
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*
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*> \param[in] UPLO
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*> \verbatim
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*> UPLO is CHARACTER*1
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*> Specifies the part of the matrix A to be set.
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*> = 'U': Upper triangular part is set. The lower triangle
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*> is unchanged.
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*> = 'L': Lower triangular part is set. The upper triangle
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*> is unchanged.
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*> Otherwise: All of the matrix A is set.
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*> \endverbatim
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*>
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*> \param[in] M
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*> \verbatim
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*> M is INTEGER
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*> On entry, M specifies the number of rows of A.
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*> \endverbatim
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*>
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*> \param[in] N
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*> \verbatim
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*> N is INTEGER
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*> On entry, N specifies the number of columns of A.
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*> \endverbatim
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*>
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*> \param[in] ALPHA
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*> \verbatim
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*> ALPHA is COMPLEX*16
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*> All the offdiagonal array elements are set to ALPHA.
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*> \endverbatim
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*>
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*> \param[in] BETA
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*> \verbatim
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*> BETA is COMPLEX*16
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*> All the diagonal array elements are set to BETA.
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*> \endverbatim
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*>
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*> \param[in,out] A
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*> \verbatim
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*> A is COMPLEX*16 array, dimension (LDA,N)
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*> On entry, the m by n matrix A.
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*> On exit, A(i,j) = ALPHA, 1 <= i <= m, 1 <= j <= n, i.ne.j;
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*> A(i,i) = BETA , 1 <= i <= min(m,n)
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*> \endverbatim
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*>
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*> \param[in] LDA
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*> \verbatim
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*> LDA is INTEGER
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*> The leading dimension of the array A. LDA >= max(1,M).
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*> \endverbatim
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*
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* Authors:
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* ========
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*
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*> \author Univ. of Tennessee
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*> \author Univ. of California Berkeley
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*> \author Univ. of Colorado Denver
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*> \author NAG Ltd.
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*
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*> \date September 2012
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*
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*> \ingroup complex16OTHERauxiliary
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*
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* =====================================================================
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SUBROUTINE
zlaset
( UPLO, M, N, ALPHA, BETA, A, LDA )
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*
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* -- LAPACK auxiliary routine (version 3.4.2) --
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* -- LAPACK is a software package provided by Univ. of Tennessee, --
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* -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
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* September 2012
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*
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* .. Scalar Arguments ..
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CHARACTER
uplo
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INTEGER
lda, m, n
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COMPLEX*16
alpha, beta
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* ..
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* .. Array Arguments ..
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COMPLEX*16
a( lda, * )
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* ..
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*
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* =====================================================================
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*
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* .. Local Scalars ..
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INTEGER
i, j
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* ..
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* .. External Functions ..
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LOGICAL
lsame
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EXTERNAL
lsame
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* ..
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* .. Intrinsic Functions ..
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INTRINSIC
min
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* ..
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* .. Executable Statements ..
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*
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IF
(
lsame
( uplo,
'U'
) )
THEN
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*
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* Set the diagonal to BETA and the strictly upper triangular
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* part of the array to ALPHA.
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*
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DO
20 j = 2, n
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DO
10 i = 1, min( j-1, m )
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a( i, j ) = alpha
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10 continue
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20 continue
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DO
30 i = 1, min( n, m )
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a( i, i ) = beta
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30 continue
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*
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ELSE
IF
(
lsame
( uplo,
'L'
) )
THEN
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*
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* Set the diagonal to BETA and the strictly lower triangular
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* part of the array to ALPHA.
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*
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DO
50 j = 1, min( m, n )
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DO
40 i = j + 1, m
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a( i, j ) = alpha
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40 continue
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50 continue
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DO
60 i = 1, min( n, m )
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a( i, i ) = beta
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60 continue
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*
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ELSE
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*
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* Set the array to BETA on the diagonal and ALPHA on the
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* offdiagonal.
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*
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DO
80 j = 1, n
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DO
70 i = 1, m
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a( i, j ) = alpha
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70 continue
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80 continue
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DO
90 i = 1, min( m, n )
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a( i, i ) = beta
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90 continue
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END IF
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*
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return
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*
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* End of ZLASET
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*
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END
SRC
zlaset.f
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