--- rpl/lapack/lapack/dpftrs.f 2011/07/22 07:38:09 1.6 +++ rpl/lapack/lapack/dpftrs.f 2011/11/21 20:43:01 1.7 @@ -1,12 +1,208 @@ - SUBROUTINE DPFTRS( TRANSR, UPLO, N, NRHS, A, B, LDB, INFO ) +*> \brief \b DPFTRS * -* -- LAPACK routine (version 3.3.1) -- +* =========== DOCUMENTATION =========== * -* -- Contributed by Fred Gustavson of the IBM Watson Research Center -- -* -- April 2011 -- +* Online html documentation available at +* http://www.netlib.org/lapack/explore-html/ * +*> \htmlonly +*> Download DPFTRS + dependencies +*> +*> [TGZ] +*> +*> [ZIP] +*> +*> [TXT] +*> \endhtmlonly +* +* Definition: +* =========== +* +* SUBROUTINE DPFTRS( TRANSR, UPLO, N, NRHS, A, B, LDB, INFO ) +* +* .. Scalar Arguments .. +* CHARACTER TRANSR, UPLO +* INTEGER INFO, LDB, N, NRHS +* .. +* .. Array Arguments .. +* DOUBLE PRECISION A( 0: * ), B( LDB, * ) +* .. +* +* +*> \par Purpose: +* ============= +*> +*> \verbatim +*> +*> DPFTRS solves a system of linear equations A*X = B with a symmetric +*> positive definite matrix A using the Cholesky factorization +*> A = U**T*U or A = L*L**T computed by DPFTRF. +*> \endverbatim +* +* Arguments: +* ========== +* +*> \param[in] TRANSR +*> \verbatim +*> TRANSR is CHARACTER*1 +*> = 'N': The Normal TRANSR of RFP A is stored; +*> = 'T': The Transpose TRANSR of RFP A is stored. +*> \endverbatim +*> +*> \param[in] UPLO +*> \verbatim +*> UPLO is CHARACTER*1 +*> = 'U': Upper triangle of RFP A is stored; +*> = 'L': Lower triangle of RFP 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 DOUBLE PRECISION array, dimension ( N*(N+1)/2 ). +*> The triangular factor U or L from the Cholesky factorization +*> of RFP A = U**T*U or RFP A = L*L**T, as computed by DPFTRF. +*> See note below for more details about RFP A. +*> \endverbatim +*> +*> \param[in,out] B +*> \verbatim +*> B is DOUBLE PRECISION 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. +* +*> \date November 2011 +* +*> \ingroup doubleOTHERcomputational +* +*> \par Further Details: +* ===================== +*> +*> \verbatim +*> +*> We first consider Rectangular Full Packed (RFP) Format when N is +*> even. We give an example where N = 6. +*> +*> AP is Upper AP is Lower +*> +*> 00 01 02 03 04 05 00 +*> 11 12 13 14 15 10 11 +*> 22 23 24 25 20 21 22 +*> 33 34 35 30 31 32 33 +*> 44 45 40 41 42 43 44 +*> 55 50 51 52 53 54 55 +*> +*> +*> Let TRANSR = 'N'. RFP holds AP as follows: +*> For UPLO = 'U' the upper trapezoid A(0:5,0:2) consists of the last +*> three columns of AP upper. The lower triangle A(4:6,0:2) consists of +*> the transpose of the first three columns of AP upper. +*> For UPLO = 'L' the lower trapezoid A(1:6,0:2) consists of the first +*> three columns of AP lower. The upper triangle A(0:2,0:2) consists of +*> the transpose of the last three columns of AP lower. +*> This covers the case N even and TRANSR = 'N'. +*> +*> RFP A RFP A +*> +*> 03 04 05 33 43 53 +*> 13 14 15 00 44 54 +*> 23 24 25 10 11 55 +*> 33 34 35 20 21 22 +*> 00 44 45 30 31 32 +*> 01 11 55 40 41 42 +*> 02 12 22 50 51 52 +*> +*> Now let TRANSR = 'T'. RFP A in both UPLO cases is just the +*> transpose of RFP A above. One therefore gets: +*> +*> +*> RFP A RFP A +*> +*> 03 13 23 33 00 01 02 33 00 10 20 30 40 50 +*> 04 14 24 34 44 11 12 43 44 11 21 31 41 51 +*> 05 15 25 35 45 55 22 53 54 55 22 32 42 52 +*> +*> +*> We then consider Rectangular Full Packed (RFP) Format when N is +*> odd. We give an example where N = 5. +*> +*> AP is Upper AP is Lower +*> +*> 00 01 02 03 04 00 +*> 11 12 13 14 10 11 +*> 22 23 24 20 21 22 +*> 33 34 30 31 32 33 +*> 44 40 41 42 43 44 +*> +*> +*> Let TRANSR = 'N'. RFP holds AP as follows: +*> For UPLO = 'U' the upper trapezoid A(0:4,0:2) consists of the last +*> three columns of AP upper. The lower triangle A(3:4,0:1) consists of +*> the transpose of the first two columns of AP upper. +*> For UPLO = 'L' the lower trapezoid A(0:4,0:2) consists of the first +*> three columns of AP lower. The upper triangle A(0:1,1:2) consists of +*> the transpose of the last two columns of AP lower. +*> This covers the case N odd and TRANSR = 'N'. +*> +*> RFP A RFP A +*> +*> 02 03 04 00 33 43 +*> 12 13 14 10 11 44 +*> 22 23 24 20 21 22 +*> 00 33 34 30 31 32 +*> 01 11 44 40 41 42 +*> +*> Now let TRANSR = 'T'. RFP A in both UPLO cases is just the +*> transpose of RFP A above. One therefore gets: +*> +*> RFP A RFP A +*> +*> 02 12 22 00 01 00 10 20 30 40 50 +*> 03 13 23 33 11 33 11 21 31 41 51 +*> 04 14 24 34 44 43 44 22 32 42 52 +*> \endverbatim +*> +* ===================================================================== + SUBROUTINE DPFTRS( TRANSR, UPLO, N, NRHS, A, B, LDB, INFO ) +* +* -- LAPACK computational 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 .. CHARACTER TRANSR, UPLO @@ -16,131 +212,6 @@ DOUBLE PRECISION A( 0: * ), B( LDB, * ) * .. * -* Purpose -* ======= -* -* DPFTRS solves a system of linear equations A*X = B with a symmetric -* positive definite matrix A using the Cholesky factorization -* A = U**T*U or A = L*L**T computed by DPFTRF. -* -* Arguments -* ========= -* -* TRANSR (input) CHARACTER*1 -* = 'N': The Normal TRANSR of RFP A is stored; -* = 'T': The Transpose TRANSR of RFP A is stored. -* -* UPLO (input) CHARACTER*1 -* = 'U': Upper triangle of RFP A is stored; -* = 'L': Lower triangle of RFP 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) DOUBLE PRECISION array, dimension ( N*(N+1)/2 ). -* The triangular factor U or L from the Cholesky factorization -* of RFP A = U**T*U or RFP A = L*L**T, as computed by DPFTRF. -* See note below for more details about RFP A. -* -* B (input/output) DOUBLE PRECISION 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 -* -* Further Details -* =============== -* -* We first consider Rectangular Full Packed (RFP) Format when N is -* even. We give an example where N = 6. -* -* AP is Upper AP is Lower -* -* 00 01 02 03 04 05 00 -* 11 12 13 14 15 10 11 -* 22 23 24 25 20 21 22 -* 33 34 35 30 31 32 33 -* 44 45 40 41 42 43 44 -* 55 50 51 52 53 54 55 -* -* -* Let TRANSR = 'N'. RFP holds AP as follows: -* For UPLO = 'U' the upper trapezoid A(0:5,0:2) consists of the last -* three columns of AP upper. The lower triangle A(4:6,0:2) consists of -* the transpose of the first three columns of AP upper. -* For UPLO = 'L' the lower trapezoid A(1:6,0:2) consists of the first -* three columns of AP lower. The upper triangle A(0:2,0:2) consists of -* the transpose of the last three columns of AP lower. -* This covers the case N even and TRANSR = 'N'. -* -* RFP A RFP A -* -* 03 04 05 33 43 53 -* 13 14 15 00 44 54 -* 23 24 25 10 11 55 -* 33 34 35 20 21 22 -* 00 44 45 30 31 32 -* 01 11 55 40 41 42 -* 02 12 22 50 51 52 -* -* Now let TRANSR = 'T'. RFP A in both UPLO cases is just the -* transpose of RFP A above. One therefore gets: -* -* -* RFP A RFP A -* -* 03 13 23 33 00 01 02 33 00 10 20 30 40 50 -* 04 14 24 34 44 11 12 43 44 11 21 31 41 51 -* 05 15 25 35 45 55 22 53 54 55 22 32 42 52 -* -* -* We then consider Rectangular Full Packed (RFP) Format when N is -* odd. We give an example where N = 5. -* -* AP is Upper AP is Lower -* -* 00 01 02 03 04 00 -* 11 12 13 14 10 11 -* 22 23 24 20 21 22 -* 33 34 30 31 32 33 -* 44 40 41 42 43 44 -* -* -* Let TRANSR = 'N'. RFP holds AP as follows: -* For UPLO = 'U' the upper trapezoid A(0:4,0:2) consists of the last -* three columns of AP upper. The lower triangle A(3:4,0:1) consists of -* the transpose of the first two columns of AP upper. -* For UPLO = 'L' the lower trapezoid A(0:4,0:2) consists of the first -* three columns of AP lower. The upper triangle A(0:1,1:2) consists of -* the transpose of the last two columns of AP lower. -* This covers the case N odd and TRANSR = 'N'. -* -* RFP A RFP A -* -* 02 03 04 00 33 43 -* 12 13 14 10 11 44 -* 22 23 24 20 21 22 -* 00 33 34 30 31 32 -* 01 11 44 40 41 42 -* -* Now let TRANSR = 'T'. RFP A in both UPLO cases is just the -* transpose of RFP A above. One therefore gets: -* -* RFP A RFP A -* -* 02 12 22 00 01 00 10 20 30 40 50 -* 03 13 23 33 11 33 11 21 31 41 51 -* 04 14 24 34 44 43 44 22 32 42 52 -* * ===================================================================== * * .. Parameters ..