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Diffstat (limited to 'BLAS/SRC/dtbmv.f')
| -rw-r--r-- | BLAS/SRC/dtbmv.f | 327 |
1 files changed, 202 insertions, 125 deletions
diff --git a/BLAS/SRC/dtbmv.f b/BLAS/SRC/dtbmv.f index 4f8778ad..ad062ca9 100644 --- a/BLAS/SRC/dtbmv.f +++ b/BLAS/SRC/dtbmv.f @@ -1,141 +1,218 @@ - SUBROUTINE DTBMV(UPLO,TRANS,DIAG,N,K,A,LDA,X,INCX) -* .. Scalar Arguments .. - INTEGER INCX,K,LDA,N - CHARACTER DIAG,TRANS,UPLO -* .. -* .. Array Arguments .. - DOUBLE PRECISION A(LDA,*),X(*) -* .. +*> \brief \b DTBMV +* +* =========== DOCUMENTATION =========== +* +* Online html documentation available at +* http://www.netlib.org/lapack/explore-html/ * +* Definition +* ========== +* +* SUBROUTINE DTBMV(UPLO,TRANS,DIAG,N,K,A,LDA,X,INCX) +* +* .. Scalar Arguments .. +* INTEGER INCX,K,LDA,N +* CHARACTER DIAG,TRANS,UPLO +* .. +* .. Array Arguments .. +* DOUBLE PRECISION A(LDA,*),X(*) +* .. +* * Purpose * ======= * -* DTBMV performs one of the matrix-vector operations +*>\details \b Purpose: +*>\verbatim +*> +*> DTBMV performs one of the matrix-vector operations +*> +*> x := A*x, or x := A**T*x, +*> +*> where x is an n element vector and A is an n by n unit, or non-unit, +*> upper or lower triangular band matrix, with ( k + 1 ) diagonals. +*> +*>\endverbatim +* +* 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 operation to be performed as +*> follows: +*> \endverbatim +*> \verbatim +*> TRANS = 'N' or 'n' x := A*x. +*> \endverbatim +*> \verbatim +*> TRANS = 'T' or 't' x := A**T*x. +*> \endverbatim +*> \verbatim +*> TRANS = 'C' or 'c' x := A**T*x. +*> \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] K +*> \verbatim +*> K is INTEGER +*> On entry with UPLO = 'U' or 'u', K specifies the number of +*> super-diagonals of the matrix A. +*> On entry with UPLO = 'L' or 'l', K specifies the number of +*> sub-diagonals of the matrix A. +*> K must satisfy 0 .le. K. +*> \endverbatim +*> +*> \param[in] A +*> \verbatim +*> A is DOUBLE PRECISION array of DIMENSION ( LDA, n ). +*> Before entry with UPLO = 'U' or 'u', the leading ( k + 1 ) +*> by n part of the array A must contain the upper triangular +*> band part of the matrix of coefficients, supplied column by +*> column, with the leading diagonal of the matrix in row +*> ( k + 1 ) of the array, the first super-diagonal starting at +*> position 2 in row k, and so on. The top left k by k triangle +*> of the array A is not referenced. +*> The following program segment will transfer an upper +*> triangular band matrix from conventional full matrix storage +*> to band storage: +*> \endverbatim +*> \verbatim +*> DO 20, J = 1, N +*> M = K + 1 - J +*> DO 10, I = MAX( 1, J - K ), J +*> A( M + I, J ) = matrix( I, J ) +*> 10 CONTINUE +*> 20 CONTINUE +*> \endverbatim +*> \verbatim +*> Before entry with UPLO = 'L' or 'l', the leading ( k + 1 ) +*> by n part of the array A must contain the lower triangular +*> band part of the matrix of coefficients, supplied column by +*> column, with the leading diagonal of the matrix in row 1 of +*> the array, the first sub-diagonal starting at position 1 in +*> row 2, and so on. The bottom right k by k triangle of the +*> array A is not referenced. +*> The following program segment will transfer a lower +*> triangular band matrix from conventional full matrix storage +*> to band storage: +*> \endverbatim +*> \verbatim +*> DO 20, J = 1, N +*> M = 1 - J +*> DO 10, I = J, MIN( N, J + K ) +*> A( M + I, J ) = matrix( I, J ) +*> 10 CONTINUE +*> 20 CONTINUE +*> \endverbatim +*> \verbatim +*> Note that when DIAG = 'U' or 'u' the elements of the array A +*> corresponding to the diagonal elements of the matrix are not +*> referenced, 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 +*> ( k + 1 ). +*> \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 vector x. On exit, X is overwritten with the +*> tranformed 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 +*> +* +* Authors +* ======= * -* x := A*x, or x := A**T*x, +*> \author Univ. of Tennessee +*> \author Univ. of California Berkeley +*> \author Univ. of Colorado Denver +*> \author NAG Ltd. * -* where x is an n element vector and A is an n by n unit, or non-unit, -* upper or lower triangular band matrix, with ( k + 1 ) diagonals. +*> \date November 2011 * -* Arguments -* ========== +*> \ingroup double_blas_level2 * -* 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 operation to be performed as -* follows: -* -* TRANS = 'N' or 'n' x := A*x. -* -* TRANS = 'T' or 't' x := A**T*x. -* -* TRANS = 'C' or 'c' x := A**T*x. -* -* 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. -* -* N - INTEGER. -* On entry, N specifies the order of the matrix A. -* N must be at least zero. -* Unchanged on exit. -* -* K - INTEGER. -* On entry with UPLO = 'U' or 'u', K specifies the number of -* super-diagonals of the matrix A. -* On entry with UPLO = 'L' or 'l', K specifies the number of -* sub-diagonals of the matrix A. -* K must satisfy 0 .le. K. -* Unchanged on exit. -* -* A - DOUBLE PRECISION array of DIMENSION ( LDA, n ). -* Before entry with UPLO = 'U' or 'u', the leading ( k + 1 ) -* by n part of the array A must contain the upper triangular -* band part of the matrix of coefficients, supplied column by -* column, with the leading diagonal of the matrix in row -* ( k + 1 ) of the array, the first super-diagonal starting at -* position 2 in row k, and so on. The top left k by k triangle -* of the array A is not referenced. -* The following program segment will transfer an upper -* triangular band matrix from conventional full matrix storage -* to band storage: -* -* DO 20, J = 1, N -* M = K + 1 - J -* DO 10, I = MAX( 1, J - K ), J -* A( M + I, J ) = matrix( I, J ) -* 10 CONTINUE -* 20 CONTINUE -* -* Before entry with UPLO = 'L' or 'l', the leading ( k + 1 ) -* by n part of the array A must contain the lower triangular -* band part of the matrix of coefficients, supplied column by -* column, with the leading diagonal of the matrix in row 1 of -* the array, the first sub-diagonal starting at position 1 in -* row 2, and so on. The bottom right k by k triangle of the -* array A is not referenced. -* The following program segment will transfer a lower -* triangular band matrix from conventional full matrix storage -* to band storage: -* -* DO 20, J = 1, N -* M = 1 - J -* DO 10, I = J, MIN( N, J + K ) -* A( M + I, J ) = matrix( I, J ) -* 10 CONTINUE -* 20 CONTINUE -* -* Note that when DIAG = 'U' or 'u' the elements of the array A -* corresponding to the diagonal elements of the matrix are not -* referenced, but are assumed to be unity. -* Unchanged on exit. -* -* LDA - INTEGER. -* On entry, LDA specifies the first dimension of A as declared -* in the calling (sub) program. LDA must be at least -* ( k + 1 ). -* Unchanged on exit. -* -* X - DOUBLE PRECISION array of dimension at least -* ( 1 + ( n - 1 )*abs( INCX ) ). -* Before entry, the incremented array X must contain the n -* element vector x. On exit, X is overwritten with the -* tranformed vector x. -* -* INCX - INTEGER. -* On entry, INCX specifies the increment for the elements of -* X. INCX must not be zero. -* Unchanged on exit. * * Further Details * =============== +*>\details \b Further \b Details +*> \verbatim +*> +*> Level 2 Blas routine. +*> The vector and matrix arguments are not referenced when N = 0, or M = 0 +*> +*> -- 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 +*> +* ===================================================================== + SUBROUTINE DTBMV(UPLO,TRANS,DIAG,N,K,A,LDA,X,INCX) * -* Level 2 Blas routine. -* The vector and matrix arguments are not referenced when N = 0, or M = 0 +* -- Reference BLAS level2 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,K,LDA,N + CHARACTER DIAG,TRANS,UPLO +* .. +* .. Array Arguments .. + DOUBLE PRECISION A(LDA,*),X(*) +* .. * * ===================================================================== * |