org.netlib.lapack
Class Dlags2

java.lang.Object
  extended by org.netlib.lapack.Dlags2

public class Dlags2
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 * ======= * * DLAGS2 computes 2-by-2 orthogonal matrices U, V and Q, such * that if ( UPPER ) then * * U'*A*Q = U'*( A1 A2 )*Q = ( x 0 ) * ( 0 A3 ) ( x x ) * and * V'*B*Q = V'*( B1 B2 )*Q = ( x 0 ) * ( 0 B3 ) ( x x ) * * or if ( .NOT.UPPER ) then * * U'*A*Q = U'*( A1 0 )*Q = ( x x ) * ( A2 A3 ) ( 0 x ) * and * V'*B*Q = V'*( B1 0 )*Q = ( x x ) * ( B2 B3 ) ( 0 x ) * * The rows of the transformed A and B are parallel, where * * U = ( CSU SNU ), V = ( CSV SNV ), Q = ( CSQ SNQ ) * ( -SNU CSU ) ( -SNV CSV ) ( -SNQ CSQ ) * * Z' denotes the transpose of Z. * * * Arguments * ========= * * UPPER (input) LOGICAL * = .TRUE.: the input matrices A and B are upper triangular. * = .FALSE.: the input matrices A and B are lower triangular. * * A1 (input) DOUBLE PRECISION * A2 (input) DOUBLE PRECISION * A3 (input) DOUBLE PRECISION * On entry, A1, A2 and A3 are elements of the input 2-by-2 * upper (lower) triangular matrix A. * * B1 (input) DOUBLE PRECISION * B2 (input) DOUBLE PRECISION * B3 (input) DOUBLE PRECISION * On entry, B1, B2 and B3 are elements of the input 2-by-2 * upper (lower) triangular matrix B. * * CSU (output) DOUBLE PRECISION * SNU (output) DOUBLE PRECISION * The desired orthogonal matrix U. * * CSV (output) DOUBLE PRECISION * SNV (output) DOUBLE PRECISION * The desired orthogonal matrix V. * * CSQ (output) DOUBLE PRECISION * SNQ (output) DOUBLE PRECISION * The desired orthogonal matrix Q. * * ===================================================================== * * .. Parameters ..


Constructor Summary
Dlags2()
           
 
Method Summary
static void dlags2(boolean upper, double a1, double a2, double a3, double b1, double b2, double b3, doubleW csu, doubleW snu, doubleW csv, doubleW snv, doubleW csq, doubleW snq)
           
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

Dlags2

public Dlags2()
Method Detail

dlags2

public static void dlags2(boolean upper,
                          double a1,
                          double a2,
                          double a3,
                          double b1,
                          double b2,
                          double b3,
                          doubleW csu,
                          doubleW snu,
                          doubleW csv,
                          doubleW snv,
                          doubleW csq,
                          doubleW snq)