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Diffstat (limited to 'BLAS/SRC/dtrsv.f')
| -rw-r--r-- | BLAS/SRC/dtrsv.f | 243 |
1 files changed, 155 insertions, 88 deletions
diff --git a/BLAS/SRC/dtrsv.f b/BLAS/SRC/dtrsv.f index f901e699..4a0845b7 100644 --- a/BLAS/SRC/dtrsv.f +++ b/BLAS/SRC/dtrsv.f @@ -1,104 +1,171 @@ - SUBROUTINE DTRSV(UPLO,TRANS,DIAG,N,A,LDA,X,INCX) -* .. Scalar Arguments .. - INTEGER INCX,LDA,N - CHARACTER DIAG,TRANS,UPLO -* .. -* .. Array Arguments .. - DOUBLE PRECISION A(LDA,*),X(*) -* .. -* -* Purpose -* ======= -* -* DTRSV solves one of the systems of equations -* -* A*x = b, or A**T*x = b, +*> \brief \b DTRSV * -* where b and x are n element vectors and A is an n by n unit, or -* non-unit, upper or lower triangular matrix. +* =========== DOCUMENTATION =========== * -* No test for singularity or near-singularity is included in this -* routine. Such tests must be performed before calling this routine. +* Online html documentation available at +* http://www.netlib.org/lapack/explore-html/ * -* Arguments +* Definition * ========== * -* UPLO - CHARACTER*1. -* On entry, UPLO specifies whether the matrix is an upper or -* lower triangular matrix as follows: -* -* UPLO = 'U' or 'u' A is an upper triangular matrix. -* -* UPLO = 'L' or 'l' A is a lower triangular matrix. -* -* Unchanged on exit. -* -* TRANS - CHARACTER*1. -* On entry, TRANS specifies the equations to be solved as -* follows: -* -* TRANS = 'N' or 'n' A*x = b. -* -* TRANS = 'T' or 't' A**T*x = b. -* -* TRANS = 'C' or 'c' A**T*x = b. -* -* Unchanged on exit. -* -* DIAG - CHARACTER*1. -* On entry, DIAG specifies whether or not A is unit -* triangular as follows: -* -* DIAG = 'U' or 'u' A is assumed to be unit triangular. -* -* DIAG = 'N' or 'n' A is not assumed to be unit -* triangular. -* -* Unchanged on exit. +* SUBROUTINE DTRSV(UPLO,TRANS,DIAG,N,A,LDA,X,INCX) +* +* .. Scalar Arguments .. +* INTEGER INCX,LDA,N +* CHARACTER DIAG,TRANS,UPLO +* .. +* .. Array Arguments .. +* DOUBLE PRECISION A(LDA,*),X(*) +* .. +* +* Purpose +* ======= * -* N - INTEGER. -* On entry, N specifies the order of the matrix A. -* N must be at least zero. -* Unchanged on exit. +*>\details \b Purpose: +*>\verbatim +*> +*> DTRSV solves one of the systems of equations +*> +*> A*x = b, or A**T*x = b, +*> +*> where b and x are n element vectors and A is an n by n unit, or +*> non-unit, upper or lower triangular matrix. +*> +*> No test for singularity or near-singularity is included in this +*> routine. Such tests must be performed before calling this routine. +*> +*>\endverbatim * -* A - DOUBLE PRECISION array of DIMENSION ( LDA, n ). -* Before entry with UPLO = 'U' or 'u', the leading n by n -* upper triangular part of the array A must contain the upper -* triangular matrix and the strictly lower triangular part of -* A is not referenced. -* Before entry with UPLO = 'L' or 'l', the leading n by n -* lower triangular part of the array A must contain the lower -* triangular matrix and the strictly upper triangular part of -* A is not referenced. -* Note that when DIAG = 'U' or 'u', the diagonal elements of -* A are not referenced either, but are assumed to be unity. -* Unchanged on exit. +* Arguments +* ========= +* +*> \param[in] UPLO +*> \verbatim +*> UPLO is CHARACTER*1 +*> On entry, UPLO specifies whether the matrix is an upper or +*> lower triangular matrix as follows: +*> \endverbatim +*> \verbatim +*> UPLO = 'U' or 'u' A is an upper triangular matrix. +*> \endverbatim +*> \verbatim +*> UPLO = 'L' or 'l' A is a lower triangular matrix. +*> \endverbatim +*> +*> \param[in] TRANS +*> \verbatim +*> TRANS is CHARACTER*1 +*> On entry, TRANS specifies the equations to be solved as +*> follows: +*> \endverbatim +*> \verbatim +*> TRANS = 'N' or 'n' A*x = b. +*> \endverbatim +*> \verbatim +*> TRANS = 'T' or 't' A**T*x = b. +*> \endverbatim +*> \verbatim +*> TRANS = 'C' or 'c' A**T*x = b. +*> \endverbatim +*> +*> \param[in] DIAG +*> \verbatim +*> DIAG is CHARACTER*1 +*> On entry, DIAG specifies whether or not A is unit +*> triangular as follows: +*> \endverbatim +*> \verbatim +*> DIAG = 'U' or 'u' A is assumed to be unit triangular. +*> \endverbatim +*> \verbatim +*> DIAG = 'N' or 'n' A is not assumed to be unit +*> triangular. +*> \endverbatim +*> +*> \param[in] N +*> \verbatim +*> N is INTEGER +*> On entry, N specifies the order of the matrix A. +*> N must be at least zero. +*> \endverbatim +*> +*> \param[in] A +*> \verbatim +*> A is DOUBLE PRECISION array of DIMENSION ( LDA, n ). +*> Before entry with UPLO = 'U' or 'u', the leading n by n +*> upper triangular part of the array A must contain the upper +*> triangular matrix and the strictly lower triangular part of +*> A is not referenced. +*> Before entry with UPLO = 'L' or 'l', the leading n by n +*> lower triangular part of the array A must contain the lower +*> triangular matrix and the strictly upper triangular part of +*> A is not referenced. +*> Note that when DIAG = 'U' or 'u', the diagonal elements of +*> A are not referenced either, but are assumed to be unity. +*> \endverbatim +*> +*> \param[in] LDA +*> \verbatim +*> LDA is INTEGER +*> On entry, LDA specifies the first dimension of A as declared +*> in the calling (sub) program. LDA must be at least +*> max( 1, n ). +*> \endverbatim +*> +*> \param[in,out] X +*> \verbatim +*> X is DOUBLE PRECISION array of dimension at least +*> ( 1 + ( n - 1 )*abs( INCX ) ). +*> Before entry, the incremented array X must contain the n +*> element right-hand side vector b. On exit, X is overwritten +*> with the solution vector x. +*> \endverbatim +*> +*> \param[in] INCX +*> \verbatim +*> INCX is INTEGER +*> On entry, INCX specifies the increment for the elements of +*> X. INCX must not be zero. +*> \endverbatim +*> \verbatim +*> Level 2 Blas routine. +*> \endverbatim +*> \verbatim +*> -- Written on 22-October-1986. +*> Jack Dongarra, Argonne National Lab. +*> Jeremy Du Croz, Nag Central Office. +*> Sven Hammarling, Nag Central Office. +*> Richard Hanson, Sandia National Labs. +*> \endverbatim +*> +* +* Authors +* ======= * -* LDA - INTEGER. -* On entry, LDA specifies the first dimension of A as declared -* in the calling (sub) program. LDA must be at least -* max( 1, n ). -* Unchanged on exit. +*> \author Univ. of Tennessee +*> \author Univ. of California Berkeley +*> \author Univ. of Colorado Denver +*> \author NAG Ltd. * -* X - DOUBLE PRECISION array of dimension at least -* ( 1 + ( n - 1 )*abs( INCX ) ). -* Before entry, the incremented array X must contain the n -* element right-hand side vector b. On exit, X is overwritten -* with the solution vector x. +*> \date November 2011 * -* INCX - INTEGER. -* On entry, INCX specifies the increment for the elements of -* X. INCX must not be zero. -* Unchanged on exit. +*> \ingroup double_blas_level1 * +* ===================================================================== + SUBROUTINE DTRSV(UPLO,TRANS,DIAG,N,A,LDA,X,INCX) * -* Level 2 Blas routine. +* -- Reference BLAS level1 routine (version 3.4.0) -- +* -- Reference BLAS is a software package provided by Univ. of Tennessee, -- +* -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..-- +* November 2011 * -* -- Written on 22-October-1986. -* Jack Dongarra, Argonne National Lab. -* Jeremy Du Croz, Nag Central Office. -* Sven Hammarling, Nag Central Office. -* Richard Hanson, Sandia National Labs. +* .. Scalar Arguments .. + INTEGER INCX,LDA,N + CHARACTER DIAG,TRANS,UPLO +* .. +* .. Array Arguments .. + DOUBLE PRECISION A(LDA,*),X(*) +* .. * * ===================================================================== * |