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dlas2.f(3)                          LAPACK                          dlas2.f(3)

NAME
       dlas2.f -

SYNOPSIS
   Functions/Subroutines
       subroutine dlas2 (F, G, H, SSMIN, SSMAX)
           DLAS2 computes singular values of a 2-by-2 triangular matrix.

Function/Subroutine Documentation
   subroutine dlas2 (double precisionF, double precisionG, double precisionH,
       double precisionSSMIN, double precisionSSMAX)
       DLAS2 computes singular values of a 2-by-2 triangular matrix.

       Purpose:

            DLAS2  computes the singular values of the 2-by-2 matrix
               [  F   G  ]
               [  0   H  ].
            On return, SSMIN is the smaller singular value and SSMAX is the
            larger singular value.

       Parameters:
           F

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

           G

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

           H

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

           SSMIN

                     SSMIN is DOUBLE PRECISION
                     The smaller singular value.

           SSMAX

                     SSMAX is DOUBLE PRECISION
                     The larger singular value.

       Author:
           Univ. of Tennessee

           Univ. of California Berkeley

           Univ. of Colorado Denver

           NAG Ltd.

       Date:
           September 2012

       Further Details:

             Barring over/underflow, all output quantities are correct to within
             a few units in the last place (ulps), even in the absence of a guard
             digit in addition/subtraction.

             In IEEE arithmetic, the code works correctly if one matrix element is
             infinite.

             Overflow will not occur unless the largest singular value itself
             overflows, or is within a few ulps of overflow. (On machines with
             partial overflow, like the Cray, overflow may occur if the largest
             singular value is within a factor of 2 of overflow.)

             Underflow is harmless if underflow is gradual. Otherwise, results
             may correspond to a matrix modified by perturbations of size near
             the underflow threshold.

       Definition at line 108 of file dlas2.f.

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

Version 3.4.2                   Sat Nov 16 2013                     dlas2.f(3)