dsbmv - vector operation y := alpha*A*x + beta*y
SUBROUTINE DSBMV(UPLO, N, K, ALPHA, A, LDA, X, INCX, BETA, Y, INCY) CHARACTER*1 UPLO INTEGER N, K, LDA, INCX, INCY DOUBLE PRECISION ALPHA, BETA DOUBLE PRECISION A(LDA,*), X(*), Y(*) SUBROUTINE DSBMV_64(UPLO, N, K, ALPHA, A, LDA, X, INCX, BETA, Y, INCY) CHARACTER*1 UPLO INTEGER*8 N, K, LDA, INCX, INCY DOUBLE PRECISION ALPHA, BETA DOUBLE PRECISION A(LDA,*), X(*), Y(*) F95 INTERFACE SUBROUTINE SBMV(UPLO, N, K, ALPHA, A, LDA, X, INCX, BETA, Y, INCY) CHARACTER(LEN=1) :: UPLO INTEGER :: N, K, LDA, INCX, INCY REAL(8) :: ALPHA, BETA REAL(8), DIMENSION(:) :: X, Y REAL(8), DIMENSION(:,:) :: A SUBROUTINE SBMV_64(UPLO, N, K, ALPHA, A, LDA, X, INCX, BETA, Y, INCY) CHARACTER(LEN=1) :: UPLO INTEGER(8) :: N, K, LDA, INCX, INCY REAL(8) :: ALPHA, BETA REAL(8), DIMENSION(:) :: X, Y REAL(8), DIMENSION(:,:) :: A C INTERFACE #include <sunperf.h> void dsbmv(char uplo, int n, int k, double alpha, double *a, int lda, double *x, int incx, double beta, double *y, int incy); void dsbmv_64(char uplo, long n, long k, double alpha, double *a, long lda, double *x, long incx, double beta, double *y, long incy);
Oracle Solaris Studio Performance Library dsbmv(3P) NAME dsbmv - perform the matrix-vector operation y := alpha*A*x + beta*y SYNOPSIS SUBROUTINE DSBMV(UPLO, N, K, ALPHA, A, LDA, X, INCX, BETA, Y, INCY) CHARACTER*1 UPLO INTEGER N, K, LDA, INCX, INCY DOUBLE PRECISION ALPHA, BETA DOUBLE PRECISION A(LDA,*), X(*), Y(*) SUBROUTINE DSBMV_64(UPLO, N, K, ALPHA, A, LDA, X, INCX, BETA, Y, INCY) CHARACTER*1 UPLO INTEGER*8 N, K, LDA, INCX, INCY DOUBLE PRECISION ALPHA, BETA DOUBLE PRECISION A(LDA,*), X(*), Y(*) F95 INTERFACE SUBROUTINE SBMV(UPLO, N, K, ALPHA, A, LDA, X, INCX, BETA, Y, INCY) CHARACTER(LEN=1) :: UPLO INTEGER :: N, K, LDA, INCX, INCY REAL(8) :: ALPHA, BETA REAL(8), DIMENSION(:) :: X, Y REAL(8), DIMENSION(:,:) :: A SUBROUTINE SBMV_64(UPLO, N, K, ALPHA, A, LDA, X, INCX, BETA, Y, INCY) CHARACTER(LEN=1) :: UPLO INTEGER(8) :: N, K, LDA, INCX, INCY REAL(8) :: ALPHA, BETA REAL(8), DIMENSION(:) :: X, Y REAL(8), DIMENSION(:,:) :: A C INTERFACE #include <sunperf.h> void dsbmv(char uplo, int n, int k, double alpha, double *a, int lda, double *x, int incx, double beta, double *y, int incy); void dsbmv_64(char uplo, long n, long k, double alpha, double *a, long lda, double *x, long incx, double beta, double *y, long incy); PURPOSE dsbmv performs the matrix-vector operation y := alpha*A*x + beta*y, where alpha and beta are scalars, x and y are n element vectors and A is an n by n symmetric band matrix, with k super-diagonals. ARGUMENTS UPLO (input) On entry, UPLO specifies whether the upper or lower triangu- lar part of the band matrix A is being supplied as follows: UPLO = 'U' or 'u' The upper triangular part of A is being supplied. UPLO = 'L' or 'l' The lower triangular part of A is being supplied. Unchanged on exit. N (input) On entry, N specifies the order of the matrix A. N >= 0. Unchanged on exit. K (input) On entry, K specifies the number of super-diagonals of the matrix A. K >= 0. Unchanged on exit. ALPHA (input) On entry, ALPHA specifies the scalar alpha. 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 symmetric matrix, 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 the upper triangular part of a symmetric 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 symmetric matrix, 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 the lower triangular part of a symmetric band matrix from conven- tional 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 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. X (input) ( 1 + ( n - 1 )*abs( INCX ) ). Before entry, the incremented array X must contain the vector x. Unchanged on exit. INCX (input) On entry, INCX specifies the increment for the elements of X. INCX <> 0. Unchanged on exit. BETA (input) On entry, BETA specifies the scalar beta. Unchanged on exit. Y (input/output) ( 1 + ( n - 1 )*abs( INCY ) ). Before entry, the incremented array Y must contain the vector y. On exit, Y is overwritten by the updated vector y. INCY (input) On entry, INCY specifies the increment for the elements of Y. INCY <> 0. Unchanged on exit. 7 Nov 2015 dsbmv(3P)