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author | julie <julielangou@users.noreply.github.com> | 2011-10-06 06:53:11 +0000 |
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committer | julie <julielangou@users.noreply.github.com> | 2011-10-06 06:53:11 +0000 |
commit | e1d39294aee16fa6db9ba079b14442358217db71 (patch) | |
tree | 30e5aa04c1f6596991fda5334f63dfb9b8027849 /SRC/zlags2.f | |
parent | 5fe0466a14e395641f4f8a300ecc9dcb8058081b (diff) | |
download | lapack-e1d39294aee16fa6db9ba079b14442358217db71.tar.gz lapack-e1d39294aee16fa6db9ba079b14442358217db71.tar.bz2 lapack-e1d39294aee16fa6db9ba079b14442358217db71.zip |
Integrating Doxygen in comments
Diffstat (limited to 'SRC/zlags2.f')
-rw-r--r-- | SRC/zlags2.f | 215 |
1 files changed, 146 insertions, 69 deletions
diff --git a/SRC/zlags2.f b/SRC/zlags2.f index 6daa241b..42ba705e 100644 --- a/SRC/zlags2.f +++ b/SRC/zlags2.f @@ -1,88 +1,165 @@ - SUBROUTINE ZLAGS2( UPPER, A1, A2, A3, B1, B2, B3, CSU, SNU, CSV, - $ SNV, CSQ, SNQ ) +*> \brief \b ZLAGS2 * -* -- LAPACK auxiliary routine (version 3.3.1) -- -* -- LAPACK is a software package provided by Univ. of Tennessee, -- -* -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..-- -* -- April 2011 -- +* =========== DOCUMENTATION =========== * -* .. Scalar Arguments .. - LOGICAL UPPER - DOUBLE PRECISION A1, A3, B1, B3, CSQ, CSU, CSV - COMPLEX*16 A2, B2, SNQ, SNU, SNV -* .. +* Online html documentation available at +* http://www.netlib.org/lapack/explore-html/ +* +* Definition +* ========== * +* SUBROUTINE ZLAGS2( UPPER, A1, A2, A3, B1, B2, B3, CSU, SNU, CSV, +* SNV, CSQ, SNQ ) +* +* .. Scalar Arguments .. +* LOGICAL UPPER +* DOUBLE PRECISION A1, A3, B1, B3, CSQ, CSU, CSV +* COMPLEX*16 A2, B2, SNQ, SNU, SNV +* .. +* * Purpose * ======= * -* ZLAGS2 computes 2-by-2 unitary matrices U, V and Q, such -* that if ( UPPER ) then -* -* U**H *A*Q = U**H *( A1 A2 )*Q = ( x 0 ) -* ( 0 A3 ) ( x x ) -* and -* V**H*B*Q = V**H *( B1 B2 )*Q = ( x 0 ) -* ( 0 B3 ) ( x x ) -* -* or if ( .NOT.UPPER ) then -* -* U**H *A*Q = U**H *( A1 0 )*Q = ( x x ) -* ( A2 A3 ) ( 0 x ) -* and -* V**H *B*Q = V**H *( B1 0 )*Q = ( x x ) -* ( B2 B3 ) ( 0 x ) -* where -* -* U = ( CSU SNU ), V = ( CSV SNV ), -* ( -SNU**H CSU ) ( -SNV**H CSV ) -* -* Q = ( CSQ SNQ ) -* ( -SNQ**H CSQ ) -* -* The rows of the transformed A and B are parallel. Moreover, if the -* input 2-by-2 matrix A is not zero, then the transformed (1,1) entry -* of A is not zero. If the input matrices A and B are both not zero, -* then the transformed (2,2) element of B is not zero, except when the -* first rows of input A and B are parallel and the second rows are -* zero. +*>\details \b Purpose: +*>\verbatim +*> +*> ZLAGS2 computes 2-by-2 unitary matrices U, V and Q, such +*> that if ( UPPER ) then +*> +*> U**H *A*Q = U**H *( A1 A2 )*Q = ( x 0 ) +*> ( 0 A3 ) ( x x ) +*> and +*> V**H*B*Q = V**H *( B1 B2 )*Q = ( x 0 ) +*> ( 0 B3 ) ( x x ) +*> +*> or if ( .NOT.UPPER ) then +*> +*> U**H *A*Q = U**H *( A1 0 )*Q = ( x x ) +*> ( A2 A3 ) ( 0 x ) +*> and +*> V**H *B*Q = V**H *( B1 0 )*Q = ( x x ) +*> ( B2 B3 ) ( 0 x ) +*> where +*> +*> U = ( CSU SNU ), V = ( CSV SNV ), +*> ( -SNU**H CSU ) ( -SNV**H CSV ) +*> +*> Q = ( CSQ SNQ ) +*> ( -SNQ**H CSQ ) +*> +*> The rows of the transformed A and B are parallel. Moreover, if the +*> input 2-by-2 matrix A is not zero, then the transformed (1,1) entry +*> of A is not zero. If the input matrices A and B are both not zero, +*> then the transformed (2,2) element of B is not zero, except when the +*> first rows of input A and B are parallel and the second rows are +*> zero. +*> +*>\endverbatim * * Arguments * ========= * -* UPPER (input) LOGICAL -* = .TRUE.: the input matrices A and B are upper triangular. -* = .FALSE.: the input matrices A and B are lower triangular. -* -* A1 (input) DOUBLE PRECISION -* -* A2 (input) COMPLEX*16 -* -* A3 (input) DOUBLE PRECISION -* On entry, A1, A2 and A3 are elements of the input 2-by-2 -* upper (lower) triangular matrix A. -* -* B1 (input) DOUBLE PRECISION -* -* B2 (input) COMPLEX*16 -* -* B3 (input) DOUBLE PRECISION -* On entry, B1, B2 and B3 are elements of the input 2-by-2 -* upper (lower) triangular matrix B. +*> \param[in] UPPER +*> \verbatim +*> UPPER is LOGICAL +*> = .TRUE.: the input matrices A and B are upper triangular. +*> = .FALSE.: the input matrices A and B are lower triangular. +*> \endverbatim +*> +*> \param[in] A1 +*> \verbatim +*> A1 is DOUBLE PRECISION +*> \endverbatim +*> +*> \param[in] A2 +*> \verbatim +*> A2 is COMPLEX*16 +*> \endverbatim +*> +*> \param[in] A3 +*> \verbatim +*> A3 is DOUBLE PRECISION +*> On entry, A1, A2 and A3 are elements of the input 2-by-2 +*> upper (lower) triangular matrix A. +*> \endverbatim +*> +*> \param[in] B1 +*> \verbatim +*> B1 is DOUBLE PRECISION +*> \endverbatim +*> +*> \param[in] B2 +*> \verbatim +*> B2 is COMPLEX*16 +*> \endverbatim +*> +*> \param[in] B3 +*> \verbatim +*> B3 is DOUBLE PRECISION +*> On entry, B1, B2 and B3 are elements of the input 2-by-2 +*> upper (lower) triangular matrix B. +*> \endverbatim +*> +*> \param[out] CSU +*> \verbatim +*> CSU is DOUBLE PRECISION +*> \endverbatim +*> +*> \param[out] SNU +*> \verbatim +*> SNU is COMPLEX*16 +*> The desired unitary matrix U. +*> \endverbatim +*> +*> \param[out] CSV +*> \verbatim +*> CSV is DOUBLE PRECISION +*> \endverbatim +*> +*> \param[out] SNV +*> \verbatim +*> SNV is COMPLEX*16 +*> The desired unitary matrix V. +*> \endverbatim +*> +*> \param[out] CSQ +*> \verbatim +*> CSQ is DOUBLE PRECISION +*> \endverbatim +*> +*> \param[out] SNQ +*> \verbatim +*> SNQ is COMPLEX*16 +*> The desired unitary matrix Q. +*> \endverbatim +*> +* +* Authors +* ======= * -* CSU (output) DOUBLE PRECISION +*> \author Univ. of Tennessee +*> \author Univ. of California Berkeley +*> \author Univ. of Colorado Denver +*> \author NAG Ltd. * -* SNU (output) COMPLEX*16 -* The desired unitary matrix U. +*> \date November 2011 * -* CSV (output) DOUBLE PRECISION +*> \ingroup complex16OTHERauxiliary * -* SNV (output) COMPLEX*16 -* The desired unitary matrix V. +* ===================================================================== + SUBROUTINE ZLAGS2( UPPER, A1, A2, A3, B1, B2, B3, CSU, SNU, CSV, + $ SNV, CSQ, SNQ ) * -* CSQ (output) DOUBLE PRECISION +* -- LAPACK auxiliary routine (version 3.3.1) -- +* -- LAPACK is a software package provided by Univ. of Tennessee, -- +* -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..-- +* November 2011 * -* SNQ (output) COMPLEX*16 -* The desired unitary matrix Q. +* .. Scalar Arguments .. + LOGICAL UPPER + DOUBLE PRECISION A1, A3, B1, B3, CSQ, CSU, CSV + COMPLEX*16 A2, B2, SNQ, SNU, SNV +* .. * * ===================================================================== * |