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Class org.netlib.blas.Dsbmv

java.lang.Object
   |
   +----org.netlib.blas.Dsbmv

public class Dsbmv

extends Object

Following is the description from the original
Fortran source.  For each array argument, the Java
version will include an integer offset parameter, so
the arguments may not match the description exactly.
Contact seymour@cs.utk.edu with any questions.

 *     ..
 *
 *  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.
 *
 *  Parameters
 *  ==========
 *
 *  UPLO   - CHARACTER*1.
 *           On entry, UPLO specifies whether the upper or lower
 *           triangular 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      - INTEGER.
 *           On entry, N specifies the order of the matrix A.
 *           N must be at least zero.
 *           Unchanged on exit.
 *
 *  K      - INTEGER.
 *           On entry, K specifies the number of super-diagonals of the
 *           matrix A. K must satisfy  0 .le. K.
 *           Unchanged on exit.
 *
 *  ALPHA  - DOUBLE PRECISION.
 *           On entry, ALPHA specifies the scalar alpha.
 *           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 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 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
 *
 *           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
 *           vector x.
 *           Unchanged on exit.
 *
 *  INCX   - INTEGER.
 *           On entry, INCX specifies the increment for the elements of
 *           X. INCX must not be zero.
 *           Unchanged on exit.
 *
 *  BETA   - DOUBLE PRECISION.
 *           On entry, BETA specifies the scalar beta.
 *           Unchanged on exit.
 *
 *  Y      - DOUBLE PRECISION array of DIMENSION at least
 *           ( 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   - INTEGER.
 *           On entry, INCY specifies the increment for the elements of
 *           Y. INCY must not be zero.
 *           Unchanged on exit.
 *
 *
 *  Level 2 Blas routine.
 *
 *  -- 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.
 *
 *
 *     .. Parameters ..

Dsbmv()

dsbmv(String, int, int, double, double[], int, int, double[], int, int, double, double[], int, int)

 public Dsbmv()

 public static void dsbmv(String uplo,
                          int n,
                          int k,
                          double alpha,
                          double a[],
                          int _a_offset,
                          int lda,
                          double x[],
                          int _x_offset,
                          int incx,
                          double beta,
                          double y[],
                          int _y_offset,
                          int incy)

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