--- rpl/lapack/lapack/zgbbrd.f 2010/08/13 21:04:01 1.6 +++ rpl/lapack/lapack/zgbbrd.f 2023/08/07 08:39:15 1.18 @@ -1,10 +1,199 @@ +*> \brief \b ZGBBRD +* +* =========== DOCUMENTATION =========== +* +* Online html documentation available at +* http://www.netlib.org/lapack/explore-html/ +* +*> \htmlonly +*> Download ZGBBRD + dependencies +*> +*> [TGZ] +*> +*> [ZIP] +*> +*> [TXT] +*> \endhtmlonly +* +* Definition: +* =========== +* +* SUBROUTINE ZGBBRD( VECT, M, N, NCC, KL, KU, AB, LDAB, D, E, Q, +* LDQ, PT, LDPT, C, LDC, WORK, RWORK, INFO ) +* +* .. Scalar Arguments .. +* CHARACTER VECT +* INTEGER INFO, KL, KU, LDAB, LDC, LDPT, LDQ, M, N, NCC +* .. +* .. Array Arguments .. +* DOUBLE PRECISION D( * ), E( * ), RWORK( * ) +* COMPLEX*16 AB( LDAB, * ), C( LDC, * ), PT( LDPT, * ), +* $ Q( LDQ, * ), WORK( * ) +* .. +* +* +*> \par Purpose: +* ============= +*> +*> \verbatim +*> +*> ZGBBRD reduces a complex general m-by-n band matrix A to real upper +*> bidiagonal form B by a unitary transformation: Q**H * A * P = B. +*> +*> The routine computes B, and optionally forms Q or P**H, or computes +*> Q**H*C for a given matrix C. +*> \endverbatim +* +* Arguments: +* ========== +* +*> \param[in] VECT +*> \verbatim +*> VECT is CHARACTER*1 +*> Specifies whether or not the matrices Q and P**H are to be +*> formed. +*> = 'N': do not form Q or P**H; +*> = 'Q': form Q only; +*> = 'P': form P**H only; +*> = 'B': form both. +*> \endverbatim +*> +*> \param[in] M +*> \verbatim +*> M is INTEGER +*> The number of rows of the matrix A. M >= 0. +*> \endverbatim +*> +*> \param[in] N +*> \verbatim +*> N is INTEGER +*> The number of columns of the matrix A. N >= 0. +*> \endverbatim +*> +*> \param[in] NCC +*> \verbatim +*> NCC is INTEGER +*> The number of columns of the matrix C. NCC >= 0. +*> \endverbatim +*> +*> \param[in] KL +*> \verbatim +*> KL is INTEGER +*> The number of subdiagonals of the matrix A. KL >= 0. +*> \endverbatim +*> +*> \param[in] KU +*> \verbatim +*> KU is INTEGER +*> The number of superdiagonals of the matrix A. KU >= 0. +*> \endverbatim +*> +*> \param[in,out] AB +*> \verbatim +*> AB is COMPLEX*16 array, dimension (LDAB,N) +*> On entry, the m-by-n band matrix A, stored in rows 1 to +*> KL+KU+1. The j-th column of A is stored in the j-th column of +*> the array AB as follows: +*> AB(ku+1+i-j,j) = A(i,j) for max(1,j-ku)<=i<=min(m,j+kl). +*> On exit, A is overwritten by values generated during the +*> reduction. +*> \endverbatim +*> +*> \param[in] LDAB +*> \verbatim +*> LDAB is INTEGER +*> The leading dimension of the array A. LDAB >= KL+KU+1. +*> \endverbatim +*> +*> \param[out] D +*> \verbatim +*> D is DOUBLE PRECISION array, dimension (min(M,N)) +*> The diagonal elements of the bidiagonal matrix B. +*> \endverbatim +*> +*> \param[out] E +*> \verbatim +*> E is DOUBLE PRECISION array, dimension (min(M,N)-1) +*> The superdiagonal elements of the bidiagonal matrix B. +*> \endverbatim +*> +*> \param[out] Q +*> \verbatim +*> Q is COMPLEX*16 array, dimension (LDQ,M) +*> If VECT = 'Q' or 'B', the m-by-m unitary matrix Q. +*> If VECT = 'N' or 'P', the array Q is not referenced. +*> \endverbatim +*> +*> \param[in] LDQ +*> \verbatim +*> LDQ is INTEGER +*> The leading dimension of the array Q. +*> LDQ >= max(1,M) if VECT = 'Q' or 'B'; LDQ >= 1 otherwise. +*> \endverbatim +*> +*> \param[out] PT +*> \verbatim +*> PT is COMPLEX*16 array, dimension (LDPT,N) +*> If VECT = 'P' or 'B', the n-by-n unitary matrix P'. +*> If VECT = 'N' or 'Q', the array PT is not referenced. +*> \endverbatim +*> +*> \param[in] LDPT +*> \verbatim +*> LDPT is INTEGER +*> The leading dimension of the array PT. +*> LDPT >= max(1,N) if VECT = 'P' or 'B'; LDPT >= 1 otherwise. +*> \endverbatim +*> +*> \param[in,out] C +*> \verbatim +*> C is COMPLEX*16 array, dimension (LDC,NCC) +*> On entry, an m-by-ncc matrix C. +*> On exit, C is overwritten by Q**H*C. +*> C is not referenced if NCC = 0. +*> \endverbatim +*> +*> \param[in] LDC +*> \verbatim +*> LDC is INTEGER +*> The leading dimension of the array C. +*> LDC >= max(1,M) if NCC > 0; LDC >= 1 if NCC = 0. +*> \endverbatim +*> +*> \param[out] WORK +*> \verbatim +*> WORK is COMPLEX*16 array, dimension (max(M,N)) +*> \endverbatim +*> +*> \param[out] RWORK +*> \verbatim +*> RWORK is DOUBLE PRECISION array, dimension (max(M,N)) +*> \endverbatim +*> +*> \param[out] INFO +*> \verbatim +*> INFO is INTEGER +*> = 0: successful exit. +*> < 0: if INFO = -i, the i-th argument had an illegal value. +*> \endverbatim +* +* Authors: +* ======== +* +*> \author Univ. of Tennessee +*> \author Univ. of California Berkeley +*> \author Univ. of Colorado Denver +*> \author NAG Ltd. +* +*> \ingroup complex16GBcomputational +* +* ===================================================================== SUBROUTINE ZGBBRD( VECT, M, N, NCC, KL, KU, AB, LDAB, D, E, Q, $ LDQ, PT, LDPT, C, LDC, WORK, RWORK, INFO ) * -* -- LAPACK routine (version 3.2) -- +* -- LAPACK computational routine -- * -- LAPACK is a software package provided by Univ. of Tennessee, -- * -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..-- -* November 2006 * * .. Scalar Arguments .. CHARACTER VECT @@ -16,91 +205,6 @@ $ Q( LDQ, * ), WORK( * ) * .. * -* Purpose -* ======= -* -* ZGBBRD reduces a complex general m-by-n band matrix A to real upper -* bidiagonal form B by a unitary transformation: Q' * A * P = B. -* -* The routine computes B, and optionally forms Q or P', or computes -* Q'*C for a given matrix C. -* -* Arguments -* ========= -* -* VECT (input) CHARACTER*1 -* Specifies whether or not the matrices Q and P' are to be -* formed. -* = 'N': do not form Q or P'; -* = 'Q': form Q only; -* = 'P': form P' only; -* = 'B': form both. -* -* M (input) INTEGER -* The number of rows of the matrix A. M >= 0. -* -* N (input) INTEGER -* The number of columns of the matrix A. N >= 0. -* -* NCC (input) INTEGER -* The number of columns of the matrix C. NCC >= 0. -* -* KL (input) INTEGER -* The number of subdiagonals of the matrix A. KL >= 0. -* -* KU (input) INTEGER -* The number of superdiagonals of the matrix A. KU >= 0. -* -* AB (input/output) COMPLEX*16 array, dimension (LDAB,N) -* On entry, the m-by-n band matrix A, stored in rows 1 to -* KL+KU+1. The j-th column of A is stored in the j-th column of -* the array AB as follows: -* AB(ku+1+i-j,j) = A(i,j) for max(1,j-ku)<=i<=min(m,j+kl). -* On exit, A is overwritten by values generated during the -* reduction. -* -* LDAB (input) INTEGER -* The leading dimension of the array A. LDAB >= KL+KU+1. -* -* D (output) DOUBLE PRECISION array, dimension (min(M,N)) -* The diagonal elements of the bidiagonal matrix B. -* -* E (output) DOUBLE PRECISION array, dimension (min(M,N)-1) -* The superdiagonal elements of the bidiagonal matrix B. -* -* Q (output) COMPLEX*16 array, dimension (LDQ,M) -* If VECT = 'Q' or 'B', the m-by-m unitary matrix Q. -* If VECT = 'N' or 'P', the array Q is not referenced. -* -* LDQ (input) INTEGER -* The leading dimension of the array Q. -* LDQ >= max(1,M) if VECT = 'Q' or 'B'; LDQ >= 1 otherwise. -* -* PT (output) COMPLEX*16 array, dimension (LDPT,N) -* If VECT = 'P' or 'B', the n-by-n unitary matrix P'. -* If VECT = 'N' or 'Q', the array PT is not referenced. -* -* LDPT (input) INTEGER -* The leading dimension of the array PT. -* LDPT >= max(1,N) if VECT = 'P' or 'B'; LDPT >= 1 otherwise. -* -* C (input/output) COMPLEX*16 array, dimension (LDC,NCC) -* On entry, an m-by-ncc matrix C. -* On exit, C is overwritten by Q'*C. -* C is not referenced if NCC = 0. -* -* LDC (input) INTEGER -* The leading dimension of the array C. -* LDC >= max(1,M) if NCC > 0; LDC >= 1 if NCC = 0. -* -* WORK (workspace) COMPLEX*16 array, dimension (max(M,N)) -* -* RWORK (workspace) DOUBLE PRECISION array, dimension (max(M,N)) -* -* INFO (output) INTEGER -* = 0: successful exit. -* < 0: if INFO = -i, the i-th argument had an illegal value. -* * ===================================================================== * * .. Parameters .. @@ -165,7 +269,7 @@ RETURN END IF * -* Initialize Q and P' to the unit matrix, if needed +* Initialize Q and P**H to the unit matrix, if needed * IF( WANTQ ) $ CALL ZLASET( 'Full', M, M, CZERO, CONE, Q, LDQ ) @@ -338,7 +442,7 @@ * IF( WANTPT ) THEN * -* accumulate product of plane rotations in P' +* accumulate product of plane rotations in P**H * DO 60 J = J1, J2, KB1 CALL ZROT( N, PT( J+KUN-1, 1 ), LDPT,