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dlasq4.f(3)                         LAPACK                         dlasq4.f(3)

NAME
       dlasq4.f -

SYNOPSIS
   Functions/Subroutines
       subroutine dlasq4 (I0, N0, Z, PP, N0IN, DMIN, DMIN1, DMIN2, DN, DN1,
           DN2, TAU, TTYPE, G)
           DLASQ4 computes an approximation to the smallest eigenvalue using
           values of d from the previous transform. Used by sbdsqr.

Function/Subroutine Documentation
   subroutine dlasq4 (integerI0, integerN0, double precision, dimension( * )Z,
       integerPP, integerN0IN, double precisionDMIN, double precisionDMIN1,
       double precisionDMIN2, double precisionDN, double precisionDN1, double
       precisionDN2, double precisionTAU, integerTTYPE, double precisionG)
       DLASQ4 computes an approximation to the smallest eigenvalue using
       values of d from the previous transform. Used by sbdsqr.

       Purpose:

            DLASQ4 computes an approximation TAU to the smallest eigenvalue
            using values of d from the previous transform.

       Parameters:
           I0

                     I0 is INTEGER
                   First index.

           N0

                     N0 is INTEGER
                   Last index.

           Z

                     Z is DOUBLE PRECISION array, dimension ( 4*N )
                   Z holds the qd array.

           PP

                     PP is INTEGER
                   PP=0 for ping, PP=1 for pong.

           N0IN

                     N0IN is INTEGER
                   The value of N0 at start of EIGTEST.

           DMIN

                     DMIN is DOUBLE PRECISION
                   Minimum value of d.

           DMIN1

                     DMIN1 is DOUBLE PRECISION
                   Minimum value of d, excluding D( N0 ).

           DMIN2

                     DMIN2 is DOUBLE PRECISION
                   Minimum value of d, excluding D( N0 ) and D( N0-1 ).

           DN

                     DN is DOUBLE PRECISION
                   d(N)

           DN1

                     DN1 is DOUBLE PRECISION
                   d(N-1)

           DN2

                     DN2 is DOUBLE PRECISION
                   d(N-2)

           TAU

                     TAU is DOUBLE PRECISION
                   This is the shift.

           TTYPE

                     TTYPE is INTEGER
                   Shift type.

           G

                     G is REAL
                   G is passed as an argument in order to save its value between
                   calls to DLASQ4.

       Author:
           Univ. of Tennessee

           Univ. of California Berkeley

           Univ. of Colorado Denver

           NAG Ltd.

       Date:
           September 2012

       Further Details:

             CNST1 = 9/16

       Definition at line 151 of file dlasq4.f.

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

Version 3.4.2                   Sat Nov 16 2013                    dlasq4.f(3)