dlags2.f(3)							      LAPACK							       dlags2.f(3)

NAME

       dlags2.f -

SYNOPSIS

   Functions/Subroutines
       subroutine dlags2 (UPPER, A1, A2, A3, B1, B2, B3, CSU, SNU, CSV, SNV, CSQ, SNQ)
	   DLAGS2

Function/Subroutine Documentation
   subroutine dlags2 (logicalUPPER, double precisionA1, double precisionA2, double precisionA3, double precisionB1, double precisionB2, double
       precisionB3, double precisionCSU, double precisionSNU, double precisionCSV, double precisionSNV, double precisionCSQ, double precisionSNQ)
       DLAGS2

       Purpose:

	    DLAGS2 computes 2-by-2 orthogonal matrices U, V and Q, such
	    that if ( UPPER ) then

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

	    or if ( .NOT.UPPER ) then

		      U**T *A*Q = U**T *( A1 0	)*Q = ( x  x  )
					( A2 A3 )     ( 0  x  )
	    and
		      V**T*B*Q = V**T*( 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**T denotes the transpose of Z.

       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 DOUBLE PRECISION

	   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 DOUBLE PRECISION

	   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 DOUBLE PRECISION
		     The desired orthogonal matrix U.

	   CSV

		     CSV is DOUBLE PRECISION

	   SNV

		     SNV is DOUBLE PRECISION
		     The desired orthogonal matrix V.

	   CSQ

		     CSQ is DOUBLE PRECISION

	   SNQ

		     SNQ is DOUBLE PRECISION
		     The desired orthogonal matrix Q.

       Author:
	   Univ. of Tennessee

	   Univ. of California Berkeley

	   Univ. of Colorado Denver

	   NAG Ltd.

       Date:
	   November 2011

       Definition at line 152 of file dlags2.f.

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

Version 3.4.1							  Sun May 26 2013						       dlags2.f(3)