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Class org.netlib.blas.DTPMV

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

public class DTPMV

extends Object

DTPMV is a simplified interface to the JLAPACK routine dtpmv.
This interface converts Java-style 2D row-major arrays into
the 1D column-major linearized arrays expected by the lower
level JLAPACK routines.  Using this interface also allows you
to omit offset and leading dimension arguments.  However, because
of these conversions, these routines will be slower than the low
level ones.  Following is the description from the original Fortran
source.  Contact seymour@cs.utk.edu with any questions.

 *     ..
 *
 *  Purpose
 *  =======
 *
 *  DTPMV  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 matrix, supplied in packed form.
 *
 *  Parameters
 *  ==========
 *
 *  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'*x.
 *
 *              TRANS = 'C' or 'c'   x := A'*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.
 *
 *  AP     - DOUBLE PRECISION array of DIMENSION at least
 *           ( ( n*( n + 1 ) )/2 ).
 *           Before entry with  UPLO = 'U' or 'u', the array AP must
 *           contain the upper triangular matrix packed sequentially,
 *           column by column, so that AP( 1 ) contains a( 1, 1 ),
 *           AP( 2 ) and AP( 3 ) contain a( 1, 2 ) and a( 2, 2 )
 *           respectively, and so on.
 *           Before entry with UPLO = 'L' or 'l', the array AP must
 *           contain the lower triangular matrix packed sequentially,
 *           column by column, so that AP( 1 ) contains a( 1, 1 ),
 *           AP( 2 ) and AP( 3 ) contain a( 2, 1 ) and a( 3, 1 )
 *           respectively, and so on.
 *           Note that when  DIAG = 'U' or 'u', the diagonal elements of
 *           A are not referenced, but are assumed to be unity.
 *           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.
 *
 *
 *  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 ..

DTPMV()

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

 public DTPMV()

 public static void DTPMV(String uplo,
                          String trans,
                          String diag,
                          int n,
                          double ap[],
                          double x[],
                          int incx)

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