NAME

SYNOPSIS

  SUBROUTINE CGBMV( TRANSA, M, N, NSUB, NSUPER, ALPHA, A, LDA, X, 
 *      INCX, BETA, Y, INCY)
  CHARACTER * 1 TRANSA
  COMPLEX ALPHA, BETA
  COMPLEX A(LDA,*), X(*), Y(*)
  INTEGER M, N, NSUB, NSUPER, LDA, INCX, INCY
 
  SUBROUTINE CGBMV_64( TRANSA, M, N, NSUB, NSUPER, ALPHA, A, LDA, X, 
 *      INCX, BETA, Y, INCY)
  CHARACTER * 1 TRANSA
  COMPLEX ALPHA, BETA
  COMPLEX A(LDA,*), X(*), Y(*)
  INTEGER*8 M, N, NSUB, NSUPER, LDA, INCX, INCY
 

F95 INTERFACE

  SUBROUTINE GBMV( [TRANSA], [M], [N], NSUB, NSUPER, ALPHA, A, [LDA], 
 *       X, [INCX], BETA, Y, [INCY])
  CHARACTER(LEN=1) :: TRANSA
  COMPLEX :: ALPHA, BETA
  COMPLEX, DIMENSION(:) :: X, Y
  COMPLEX, DIMENSION(:,:) :: A
  INTEGER :: M, N, NSUB, NSUPER, LDA, INCX, INCY
 
  SUBROUTINE GBMV_64( [TRANSA], [M], [N], NSUB, NSUPER, ALPHA, A, [LDA], 
 *       X, [INCX], BETA, Y, [INCY])
  CHARACTER(LEN=1) :: TRANSA
  COMPLEX :: ALPHA, BETA
  COMPLEX, DIMENSION(:) :: X, Y
  COMPLEX, DIMENSION(:,:) :: A
  INTEGER(8) :: M, N, NSUB, NSUPER, LDA, INCX, INCY
 

C INTERFACE

void cgbmv(char transa, int m, int n, int nsub, int nsuper, complex alpha, complex *a, int lda, complex *x, int incx, complex beta, complex *y, int incy);

void cgbmv_64(char transa, long m, long n, long nsub, long nsuper, complex alpha, complex *a, long lda, complex *x, long incx, complex beta, complex *y, long incy);

PURPOSE

ARGUMENTS

* TRANSA (input)

On entry, TRANSA specifies the operation to be performed as follows:

TRANSA = 'N' or 'n' y := alpha*A*x + beta*y.

TRANSA = 'T' or 't' y := alpha*A'*x + beta*y.

TRANSA = 'C' or 'c' y := alpha*conjg( A' )*x + beta*y.

Unchanged on exit.

* M (input)

On entry, M specifies the number of rows of the matrix A. M must be at least zero. Unchanged on exit.

* N (input)

On entry, N specifies the number of columns of the matrix A. N must be at least zero. Unchanged on exit.

* NSUB (input)

On entry, NSUB specifies the number of sub-diagonals of the matrix A. NSUB must satisfy 0 .le. NSUB. Unchanged on exit.

* NSUPER (input)

On entry, NSUPER specifies the number of super-diagonals of the matrix A. NSUPER must satisfy 0 .le. NSUPER. Unchanged on exit.

* ALPHA (input)

On entry, ALPHA specifies the scalar alpha. Unchanged on exit.

* A (input)

Before entry, the leading ( kl + ku + 1 ) by n part of the array A must contain the matrix of coefficients, supplied column by column, with the leading diagonal of the matrix in row ( ku + 1 ) of the array, the first super-diagonal starting at position 2 in row ku, the first sub-diagonal starting at position 1 in row ( ku + 2 ), and so on. Elements in the array A that do not correspond to elements in the band matrix (such as the top left ku by ku triangle) are not referenced. The following program segment will transfer a band matrix from conventional full matrix storage to band storage:

    DO 20, J = 1, N
    K = NSUPER + 1 - J
      DO 10, I = MAX( 1, J - NSUPER ), MIN( M, J + NSUB )
        A( K + 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 must be at least ( kl + ku + 1 ). Unchanged on exit.

* X (input)

( 1 + ( n - 1 )*abs( INCX ) ) when TRANSA = 'N' or 'n' and at least ( 1 + ( m - 1 )*abs( INCX ) ) otherwise. 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 must not be zero. Unchanged on exit.

* BETA (input)

On entry, BETA specifies the scalar beta. When BETA is supplied as zero then Y need not be set on input. Unchanged on exit.

* Y (input/output)

( 1 + ( m - 1 )*abs( INCY ) ) when TRANSA = 'N' or 'n' and at least ( 1 + ( n - 1 )*abs( INCY ) ) otherwise. 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 must not be zero. Unchanged on exit.