SUBROUTINE DIFEX2 (N,FCN,T,Y,TEND,EPS,HMAX,H,KFLAG)
C
C* Begin Prologue DIFEX2
C
C  ---------------------------------------------------------------------
C
C* Title
C
C    Explicit extrapolation integrator for non-stiff systems of
C    second-order differential equations with the first derivative
C    absent in the right-hand side (based on Stoermer discretization).
C
C    Special version adapted for possible call in the multiple shooting
C    code BVPSOL.
C
C* Written by        P. Deuflhard, U. Nowak, U. Poehle
C* Purpose           Solution of systems of initial value problems
C* Method            Explicit mid-point rule discretization with
C                    h**2-extrapolation
C* Category          i1a1c2. - System of nonstiff second order
C                              differential equations
C* Keywords          extrapolation, ODE, explicit mid-point rule,
C                    non-stiff
C* Version           1.0 , August 1982
C* Latest Change     Februar 1991
C* Library           CodeLib
C* Code              Fortran 77
C                    Double Precision
C* Environment       Standard version for FORTRAN77 environments on
C                    PCs, workstations, and hosts
C* Copyright     (c) Konrad-Zuse-Zentrum fuer Informationstechnik
C                    Berlin (ZIB)
C                    Takustrasse 7, D-14195 Berlin-Dahlem
C                    phone : + 49/30/84185-0
C                    fax   : + 49/30/84185-125
C* Contact           Uwe Poehle
C                    ZIB, Scientific Software Group
C                    phone : + 49/30/84185-241
C                    fax   : + 49/30/84185-107
C                    e-mail: poehle@zib.de
C
C  ---------------------------------------------------------------------

The distribution contains the following files:

  difex2.f         the solver
  difex2.nrm       output of the example
  main_difex2.f    main example program
  makefile         makefile for compilation
  readme           this file
  zibconst.f       machine dependant constants