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slas2.f(3)                          LAPACK                          slas2.f(3)

NAME
       slas2.f -

SYNOPSIS
   Functions/Subroutines
       subroutine slas2 (F, G, H, SSMIN, SSMAX)
           SLAS2 computes singular values of a 2-by-2 triangular matrix.

Function/Subroutine Documentation
   subroutine slas2 (realF, realG, realH, realSSMIN, realSSMAX)
       SLAS2 computes singular values of a 2-by-2 triangular matrix.

       Purpose:

            SLAS2  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 REAL
                     The (1,1) element of the 2-by-2 matrix.

           G

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

           H

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

           SSMIN

                     SSMIN is REAL
                     The smaller singular value.

           SSMAX

                     SSMAX is REAL
                     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 slas2.f.

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

Version 3.4.2                   Sat Nov 16 2013                     slas2.f(3)