zlags2.f(3)							      LAPACK							       zlags2.f(3)

NAME

       zlags2.f -

SYNOPSIS

   Functions/Subroutines
       subroutine zlags2 (UPPER, A1, A2, A3, B1, B2, B3, CSU, SNU, CSV, SNV, CSQ, SNQ)
	   ZLAGS2

Function/Subroutine Documentation
   subroutine zlags2 (logicalUPPER, double precisionA1, complex*16A2, double precisionA3, double precisionB1, complex*16B2, double precisionB3,
       double precisionCSU, complex*16SNU, double precisionCSV, complex*16SNV, double precisionCSQ, complex*16SNQ)
       ZLAGS2

       Purpose:

	    ZLAGS2 computes 2-by-2 unitary matrices U, V and Q, such
	    that if ( UPPER ) then

		      U**H *A*Q = U**H *( A1 A2 )*Q = ( x  0  )
					( 0  A3 )     ( x  x  )
	    and
		      V**H*B*Q = V**H *( B1 B2 )*Q = ( x  0  )
				       ( 0  B3 )     ( x  x  )

	    or if ( .NOT.UPPER ) then

		      U**H *A*Q = U**H *( A1 0	)*Q = ( x  x  )
					( A2 A3 )     ( 0  x  )
	    and
		      V**H *B*Q = V**H *( B1 0	)*Q = ( x  x  )
					( B2 B3 )     ( 0  x  )
	    where

	      U = (   CSU    SNU ), V = (  CSV	  SNV ),
		  ( -SNU**H  CSU )	( -SNV**H CSV )

	      Q = (   CSQ    SNQ )
		  ( -SNQ**H  CSQ )

	    The rows of the transformed A and B are parallel. Moreover, if the
	    input 2-by-2 matrix A is not zero, then the transformed (1,1) entry
	    of A is not zero. If the input matrices A and B are both not zero,
	    then the transformed (2,2) element of B is not zero, except when the
	    first rows of input A and B are parallel and the second rows are
	    zero.

       Parameters:
	   UPPER

		     UPPER is LOGICAL
		     = .TRUE.: the input matrices A and B are upper triangular.
		     = .FALSE.: the input matrices A and B are lower triangular.

	   A1

		     A1 is DOUBLE PRECISION

	   A2

		     A2 is COMPLEX*16

	   A3

		     A3 is DOUBLE PRECISION
		     On entry, A1, A2 and A3 are elements of the input 2-by-2
		     upper (lower) triangular matrix A.

	   B1

		     B1 is DOUBLE PRECISION

	   B2

		     B2 is COMPLEX*16

	   B3

		     B3 is DOUBLE PRECISION
		     On entry, B1, B2 and B3 are elements of the input 2-by-2
		     upper (lower) triangular matrix B.

	   CSU

		     CSU is DOUBLE PRECISION

	   SNU

		     SNU is COMPLEX*16
		     The desired unitary matrix U.

	   CSV

		     CSV is DOUBLE PRECISION

	   SNV

		     SNV is COMPLEX*16
		     The desired unitary matrix V.

	   CSQ

		     CSQ is DOUBLE PRECISION

	   SNQ

		     SNQ is COMPLEX*16
		     The desired unitary matrix Q.

       Author:
	   Univ. of Tennessee

	   Univ. of California Berkeley

	   Univ. of Colorado Denver

	   NAG Ltd.

       Date:
	   November 2011

       Definition at line 158 of file zlags2.f.

Author
       Generated automatically by Doxygen for LAPACK from the source code.

Version 3.4.2							  Tue Sep 25 2012						       zlags2.f(3)