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Class org.netlib.lapack.DLANV2

java.lang.Object
   |
   +----org.netlib.lapack.DLANV2

public class DLANV2

extends Object

DLANV2 is a simplified interface to the JLAPACK routine dlanv2.
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
 *  =======
 *
 *  DLANV2 computes the Schur factorization of a real 2-by-2 nonsymmetric
 *  matrix in standard form:
 *
 *       [ A  B ] = [ CS -SN ] [ AA  BB ] [ CS  SN ]
 *       [ C  D ]   [ SN  CS ] [ CC  DD ] [-SN  CS ]
 *
 *  where either
 *  1) CC = 0 so that AA and DD are real eigenvalues of the matrix, or
 *  2) AA = DD and BB*CC < 0, so that AA + or - sqrt(BB*CC) are complex
 *  conjugate eigenvalues.
 *
 *  Arguments
 *  =========
 *
 *  A       (input/output) DOUBLE PRECISION
 *  B       (input/output) DOUBLE PRECISION
 *  C       (input/output) DOUBLE PRECISION
 *  D       (input/output) DOUBLE PRECISION
 *          On entry, the elements of the input matrix.
 *          On exit, they are overwritten by the elements of the
 *          standardised Schur form.
 *
 *  RT1R    (output) DOUBLE PRECISION
 *  RT1I    (output) DOUBLE PRECISION
 *  RT2R    (output) DOUBLE PRECISION
 *  RT2I    (output) DOUBLE PRECISION
 *          The real and imaginary parts of the eigenvalues. If the
 *          eigenvalues are both real, abs(RT1R) >= abs(RT2R); if the
 *          eigenvalues are a complex conjugate pair, RT1I > 0.
 *
 *  CS      (output) DOUBLE PRECISION
 *  SN      (output) DOUBLE PRECISION
 *          Parameters of the rotation matrix.
 *
 *  =====================================================================
 *
 *     .. Parameters ..

DLANV2()

DLANV2(doubleW, doubleW, doubleW, doubleW, doubleW, doubleW, doubleW, doubleW, doubleW, doubleW)

 public DLANV2()

 public static void DLANV2(doubleW a,
                           doubleW b,
                           doubleW c,
                           doubleW d,
                           doubleW rt1r,
                           doubleW rt1i,
                           doubleW rt2r,
                           doubleW rt2i,
                           doubleW cs,
                           doubleW sn)

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