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dlae2.f(3)				      LAPACK				       dlae2.f(3)

NAME
       dlae2.f -

SYNOPSIS
   Functions/Subroutines
       subroutine dlae2 (A, B, C, RT1, RT2)
	   DLAE2 computes the eigenvalues of a 2-by-2 symmetric matrix.

Function/Subroutine Documentation
   subroutine dlae2 (double precisionA, double precisionB, double precisionC, double
       precisionRT1, double precisionRT2)
       DLAE2 computes the eigenvalues of a 2-by-2 symmetric matrix.

       Purpose:

	    DLAE2  computes the eigenvalues of a 2-by-2 symmetric matrix
	       [  A   B  ]
	       [  B   C  ].
	    On return, RT1 is the eigenvalue of larger absolute value, and RT2
	    is the eigenvalue of smaller absolute value.

       Parameters:
	   A

		     A is DOUBLE PRECISION
		     The (1,1) element of the 2-by-2 matrix.

	   B

		     B is DOUBLE PRECISION
		     The (1,2) and (2,1) elements of the 2-by-2 matrix.

	   C

		     C is DOUBLE PRECISION
		     The (2,2) element of the 2-by-2 matrix.

	   RT1

		     RT1 is DOUBLE PRECISION
		     The eigenvalue of larger absolute value.

	   RT2

		     RT2 is DOUBLE PRECISION
		     The eigenvalue of smaller absolute value.

       Author:
	   Univ. of Tennessee

	   Univ. of California Berkeley

	   Univ. of Colorado Denver

	   NAG Ltd.

       Date:
	   September 2012

       Further Details:

	     RT1 is accurate to a few ulps barring over/underflow.

	     RT2 may be inaccurate if there is massive cancellation in the
	     determinant A*C-B*B; higher precision or correctly rounded or
	     correctly truncated arithmetic would be needed to compute RT2
	     accurately in all cases.

	     Overflow is possible only if RT1 is within a factor of 5 of overflow.
	     Underflow is harmless if the input data is 0 or exceeds
		underflow_threshold / macheps.

       Definition at line 103 of file dlae2.f.

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

Version 3.4.2				 Tue Sep 25 2012			       dlae2.f(3)
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