--- rpl/lapack/lapack/zpotrs.f 2010/12/21 13:53:53 1.7 +++ rpl/lapack/lapack/zpotrs.f 2023/08/07 08:39:34 1.18 @@ -1,9 +1,116 @@ +*> \brief \b ZPOTRS +* +* =========== DOCUMENTATION =========== +* +* Online html documentation available at +* http://www.netlib.org/lapack/explore-html/ +* +*> \htmlonly +*> Download ZPOTRS + dependencies +*> +*> [TGZ] +*> +*> [ZIP] +*> +*> [TXT] +*> \endhtmlonly +* +* Definition: +* =========== +* +* SUBROUTINE ZPOTRS( UPLO, N, NRHS, A, LDA, B, LDB, INFO ) +* +* .. Scalar Arguments .. +* CHARACTER UPLO +* INTEGER INFO, LDA, LDB, N, NRHS +* .. +* .. Array Arguments .. +* COMPLEX*16 A( LDA, * ), B( LDB, * ) +* .. +* +* +*> \par Purpose: +* ============= +*> +*> \verbatim +*> +*> ZPOTRS solves a system of linear equations A*X = B with a Hermitian +*> positive definite matrix A using the Cholesky factorization +*> A = U**H * U or A = L * L**H computed by ZPOTRF. +*> \endverbatim +* +* Arguments: +* ========== +* +*> \param[in] UPLO +*> \verbatim +*> UPLO is CHARACTER*1 +*> = 'U': Upper triangle of A is stored; +*> = 'L': Lower triangle of A is stored. +*> \endverbatim +*> +*> \param[in] N +*> \verbatim +*> N is INTEGER +*> The order of the matrix A. N >= 0. +*> \endverbatim +*> +*> \param[in] NRHS +*> \verbatim +*> NRHS is INTEGER +*> The number of right hand sides, i.e., the number of columns +*> of the matrix B. NRHS >= 0. +*> \endverbatim +*> +*> \param[in] A +*> \verbatim +*> A is COMPLEX*16 array, dimension (LDA,N) +*> The triangular factor U or L from the Cholesky factorization +*> A = U**H * U or A = L * L**H, as computed by ZPOTRF. +*> \endverbatim +*> +*> \param[in] LDA +*> \verbatim +*> LDA is INTEGER +*> The leading dimension of the array A. LDA >= max(1,N). +*> \endverbatim +*> +*> \param[in,out] B +*> \verbatim +*> B is COMPLEX*16 array, dimension (LDB,NRHS) +*> On entry, the right hand side matrix B. +*> On exit, the solution matrix X. +*> \endverbatim +*> +*> \param[in] LDB +*> \verbatim +*> LDB is INTEGER +*> The leading dimension of the array B. LDB >= max(1,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 complex16POcomputational +* +* ===================================================================== SUBROUTINE ZPOTRS( UPLO, N, NRHS, A, LDA, B, LDB, 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 UPLO @@ -13,45 +120,6 @@ COMPLEX*16 A( LDA, * ), B( LDB, * ) * .. * -* Purpose -* ======= -* -* ZPOTRS solves a system of linear equations A*X = B with a Hermitian -* positive definite matrix A using the Cholesky factorization -* A = U**H*U or A = L*L**H computed by ZPOTRF. -* -* Arguments -* ========= -* -* UPLO (input) CHARACTER*1 -* = 'U': Upper triangle of A is stored; -* = 'L': Lower triangle of A is stored. -* -* N (input) INTEGER -* The order of the matrix A. N >= 0. -* -* NRHS (input) INTEGER -* The number of right hand sides, i.e., the number of columns -* of the matrix B. NRHS >= 0. -* -* A (input) COMPLEX*16 array, dimension (LDA,N) -* The triangular factor U or L from the Cholesky factorization -* A = U**H*U or A = L*L**H, as computed by ZPOTRF. -* -* LDA (input) INTEGER -* The leading dimension of the array A. LDA >= max(1,N). -* -* B (input/output) COMPLEX*16 array, dimension (LDB,NRHS) -* On entry, the right hand side matrix B. -* On exit, the solution matrix X. -* -* LDB (input) INTEGER -* The leading dimension of the array B. LDB >= max(1,N). -* -* INFO (output) INTEGER -* = 0: successful exit -* < 0: if INFO = -i, the i-th argument had an illegal value -* * ===================================================================== * * .. Parameters .. @@ -100,9 +168,9 @@ * IF( UPPER ) THEN * -* Solve A*X = B where A = U'*U. +* Solve A*X = B where A = U**H *U. * -* Solve U'*X = B, overwriting B with X. +* Solve U**H *X = B, overwriting B with X. * CALL ZTRSM( 'Left', 'Upper', 'Conjugate transpose', 'Non-unit', $ N, NRHS, ONE, A, LDA, B, LDB ) @@ -113,14 +181,14 @@ $ NRHS, ONE, A, LDA, B, LDB ) ELSE * -* Solve A*X = B where A = L*L'. +* Solve A*X = B where A = L*L**H. * * Solve L*X = B, overwriting B with X. * CALL ZTRSM( 'Left', 'Lower', 'No transpose', 'Non-unit', N, $ NRHS, ONE, A, LDA, B, LDB ) * -* Solve L'*X = B, overwriting B with X. +* Solve L**H *X = B, overwriting B with X. * CALL ZTRSM( 'Left', 'Lower', 'Conjugate transpose', 'Non-unit', $ N, NRHS, ONE, A, LDA, B, LDB )