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PROBLEMS   311
                Table P6.9 Comparison of the BVP Solver Routines bvp2 shoot()/bvp2 fdf()

                                                      Mismatching Error
                        BVP              Routine         (P6.9.0b)      Times
                                       bvp2 shoot()      1.5 × 10 −6
                 (P6.9.1)
                 N = 100, tol = 1e-6,  bvp2 fdf()
                 kmax = 10                                     −6
                                       bvp4c()           2.9 × 10
                                       bvp2 shoot()
                 (P6.9.2)
                 N = 100, tol = 1e-6,  bvp2 fdf()       1.6 × 10 −23
                 kmax = 10
                                       bvp4c()
                                       bvp2 shoot()     1.7 × 10 −17
                 (P6.9.3)
                 N = 100, tol = 1e-6,  bvp2 fdf()
                 kmax = 10
                                       bvp4c()          7.8 × 10 −14
                                       bvp2 shoot()
                 (P6.9.4)
                 N = 100, tol = 1e-6,  bvp2 fdf()       4.4 × 10 −27
                 kmax = 10
                                       bvp4c()
                                       bvp2 shoot()      8.9 × 10 −9
                 (P6.9.5)
                 N = 100, tol = 1e-6,  bvp2 fdf()
                 kmax = 10                                     −7
                                       bvp4c()           8.9 × 10
                                       bvp2 shoot()
                 (P6.9.6)
                 N = 100, tol =1e-6,   bvp2 fdf()       4.4 × 10 −25
                 kmax =10
                                       bvp4c()


                             N−1
                         1         (2)                          2
                  err =         {D y(x i ) − f(Dy(x i ), y(x i ), u(x i ))}  (P6.9.0b)
                       N − 1
                              i=1
                with
                            y(x i+1 ) − 2y(x i ) + y(x i−1 )   y(x i+1 ) − y(x i−1 )
                   (2)
                 D y(x i ) =                       ,  Dy(x i ) =
                                      h 2                            2h
                                                                       (P6.9.0c)
                                                  x f − x 0
                              x i = x 0 + ih,  h =                     (P6.9.0d)
                                                     N
                and can be computed by using the following routine “err_of_sol_de()”.
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