org.netlib.lapack
Class Dlanv2
java.lang.Object
org.netlib.lapack.Dlanv2
public class Dlanv2
- extends java.lang.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
* =======
*
* 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 a complex conjugate pair, RT1I > 0.
*
* CS (output) DOUBLE PRECISION
* SN (output) DOUBLE PRECISION
* Parameters of the rotation matrix.
*
* Further Details
* ===============
*
* Modified by V. Sima, Research Institute for Informatics, Bucharest,
* Romania, to reduce the risk of cancellation errors,
* when computing real eigenvalues, and to ensure, if possible, that
* abs(RT1R) >= abs(RT2R).
*
* =====================================================================
*
* .. Parameters ..
Method Summary |
static void |
dlanv2(org.netlib.util.doubleW a,
org.netlib.util.doubleW b,
org.netlib.util.doubleW c,
org.netlib.util.doubleW d,
org.netlib.util.doubleW rt1r,
org.netlib.util.doubleW rt1i,
org.netlib.util.doubleW rt2r,
org.netlib.util.doubleW rt2i,
org.netlib.util.doubleW cs,
org.netlib.util.doubleW sn)
|
Methods inherited from class java.lang.Object |
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait |
Dlanv2
public Dlanv2()
dlanv2
public static void dlanv2(org.netlib.util.doubleW a,
org.netlib.util.doubleW b,
org.netlib.util.doubleW c,
org.netlib.util.doubleW d,
org.netlib.util.doubleW rt1r,
org.netlib.util.doubleW rt1i,
org.netlib.util.doubleW rt2r,
org.netlib.util.doubleW rt2i,
org.netlib.util.doubleW cs,
org.netlib.util.doubleW sn)