ZLANV2(3)     ScaLAPACK routine of NEC Numeric Library Collection    ZLANV2(3)



NAME
       ZLANV2  - compute the Schur factorization of a complex 2-by-2 nonhermi-
       tian matrix in standard form

SYNOPSIS
       SUBROUTINE ZLANV2( A, B, C, D, RT1, RT2, CS, SN )

           DOUBLE         PRECISION CS

           COMPLEX*16     A, B, C, D, RT1, RT2, SN

PURPOSE
       ZLANV2 computes the Schur factorization of a complex  2-by-2  nonhermi-
       tian matrix in standard form:
            [ A  B ] = [ CS -SN ] [ AA  BB ] [ CS  SN ]
            [ C  D ]   [ SN  CS ] [  0  DD ] [-SN  CS ]


ARGUMENTS
       A       (input/output) COMPLEX*16
               B        (input/output)  COMPLEX*16 C       (input/output) COM-
               PLEX*16 D       (input/output) COMPLEX*16 On  entry,  the  ele-
               ments  of  the  input matrix.  On exit, they are overwritten by
               the elements of the standardised Schur form.

       RT1     (output) COMPLEX*16
               RT2     (output) COMPLEX*16 The two eigenvalues.

       CS      (output) DOUBLE PRECISION
               SN      (output) COMPLEX*16 Parameters of the rotation  matrix.

FURTHER DETAILS
       Implemented by Mark R. Fahey, May 28, 1999




ScaLAPACK routine               31 October 2017                      ZLANV2(3)