dtbmv - vector operations x := A*x, or x := A'*x
SUBROUTINE DTBMV(UPLO, TRANSA, DIAG, N, K, A, LDA, Y, INCY) CHARACTER*1 UPLO, TRANSA, DIAG INTEGER N, K, LDA, INCY DOUBLE PRECISION A(LDA,*), Y(*) SUBROUTINE DTBMV_64(UPLO, TRANSA, DIAG, N, K, A, LDA, Y, INCY) CHARACTER*1 UPLO, TRANSA, DIAG INTEGER*8 N, K, LDA, INCY DOUBLE PRECISION A(LDA,*), Y(*) F95 INTERFACE SUBROUTINE TBMV(UPLO, TRANSA, DIAG, N, K, A, LDA, Y, INCY) CHARACTER(LEN=1) :: UPLO, TRANSA, DIAG INTEGER :: N, K, LDA, INCY REAL(8), DIMENSION(:) :: Y REAL(8), DIMENSION(:,:) :: A SUBROUTINE TBMV_64(UPLO, TRANSA, DIAG, N, K, A, LDA, Y, INCY) CHARACTER(LEN=1) :: UPLO, TRANSA, DIAG INTEGER(8) :: N, K, LDA, INCY REAL(8), DIMENSION(:) :: Y REAL(8), DIMENSION(:,:) :: A C INTERFACE #include <sunperf.h> void dtbmv(char uplo, char transa, char diag, int n, int k, double *a, int lda, double *y, int incy); void dtbmv_64(char uplo, char transa, char diag, long n, long k, double *a, long lda, double *y, long incy);
Oracle Solaris Studio Performance Library dtbmv(3P) NAME dtbmv - perform one of the matrix-vector operations x := A*x, or x := A'*x SYNOPSIS SUBROUTINE DTBMV(UPLO, TRANSA, DIAG, N, K, A, LDA, Y, INCY) CHARACTER*1 UPLO, TRANSA, DIAG INTEGER N, K, LDA, INCY DOUBLE PRECISION A(LDA,*), Y(*) SUBROUTINE DTBMV_64(UPLO, TRANSA, DIAG, N, K, A, LDA, Y, INCY) CHARACTER*1 UPLO, TRANSA, DIAG INTEGER*8 N, K, LDA, INCY DOUBLE PRECISION A(LDA,*), Y(*) F95 INTERFACE SUBROUTINE TBMV(UPLO, TRANSA, DIAG, N, K, A, LDA, Y, INCY) CHARACTER(LEN=1) :: UPLO, TRANSA, DIAG INTEGER :: N, K, LDA, INCY REAL(8), DIMENSION(:) :: Y REAL(8), DIMENSION(:,:) :: A SUBROUTINE TBMV_64(UPLO, TRANSA, DIAG, N, K, A, LDA, Y, INCY) CHARACTER(LEN=1) :: UPLO, TRANSA, DIAG INTEGER(8) :: N, K, LDA, INCY REAL(8), DIMENSION(:) :: Y REAL(8), DIMENSION(:,:) :: A C INTERFACE #include <sunperf.h> void dtbmv(char uplo, char transa, char diag, int n, int k, double *a, int lda, double *y, int incy); void dtbmv_64(char uplo, char transa, char diag, long n, long k, double *a, long lda, double *y, long incy); PURPOSE dtbmv performs one of the matrix-vector operations x := A*x, or x := A'*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. ARGUMENTS UPLO (input) 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. TRANSA (input) On entry, TRANSA specifies the operation to be performed as follows: TRANSA = 'N' or 'n' x := A*x. TRANSA = 'T' or 't' x := A'*x. TRANSA = 'C' or 'c' x := A'*x. Unchanged on exit. DIAG (input) 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 (input) On entry, N specifies the order of the matrix A. N >= 0. Unchanged on exit. K (input) 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 >= 0. Unchanged on exit. A (input) 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 col- umn, 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 conven- tional 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 col- umn, 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 trans- fer 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 (input) On entry, LDA specifies the first dimension of A as declared in the calling (sub) program. LDA >= ( k + 1 ). Unchanged on exit. Y (input/output) ( 1 + ( n - 1 )*abs( INCY ) ). Before entry, the incremented array Y must contain the n element vector x. On exit, Y is overwritten with the tranformed vector x. INCY (input) On entry, INCY specifies the increment for the elements of Y. INCY <> 0. Unchanged on exit. 7 Nov 2015 dtbmv(3P)