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Class org.netlib.lapack.DLARTG

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

public class DLARTG

extends Object

DLARTG is a simplified interface to the JLAPACK routine dlartg.
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
 *  =======
 *
 *  DLARTG generate a plane rotation so that
 *
 *     [  CS  SN  ]  .  [ F ]  =  [ R ]   where CS**2 + SN**2 = 1.
 *     [ -SN  CS  ]     [ G ]     [ 0 ]
 *
 *  This is a slower, more accurate version of the BLAS1 routine DROTG,
 *  with the following other differences:
 *     F and G are unchanged on return.
 *     If G=0, then CS=1 and SN=0.
 *     If F=0 and (G .ne. 0), then CS=0 and SN=1 without doing any
 *        floating point operations (saves work in DBDSQR when
 *        there are zeros on the diagonal).
 *
 *  If F exceeds G in magnitude, CS will be positive.
 *
 *  Arguments
 *  =========
 *
 *  F       (input) DOUBLE PRECISION
 *          The first component of vector to be rotated.
 *
 *  G       (input) DOUBLE PRECISION
 *          The second component of vector to be rotated.
 *
 *  CS      (output) DOUBLE PRECISION
 *          The cosine of the rotation.
 *
 *  SN      (output) DOUBLE PRECISION
 *          The sine of the rotation.
 *
 *  R       (output) DOUBLE PRECISION
 *          The nonzero component of the rotated vector.
 *
 *  =====================================================================
 *
 *     .. Parameters ..

DLARTG()

DLARTG(double, double, doubleW, doubleW, doubleW)

 public DLARTG()

 public static void DLARTG(double f,
                           double g,
                           doubleW cs,
                           doubleW sn,
                           doubleW r)

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