polynomial: 
           x            DDPOLY          actual
       0.100000       -0.590490       -0.590490
       0.200000       -0.327680       -0.327680
       0.300000       -0.168070       -0.168070
       0.400000       -0.077760       -0.077760
       0.500000       -0.031250       -0.031250
       0.600000       -0.010240       -0.010240
       0.700000       -0.002430       -0.002430
       0.800000       -0.000320       -0.000320
       0.900000       -0.000010       -0.000010
       1.000000        0.000000        0.000000
       1.100000        0.000010        0.000010
       1.200000        0.000320        0.000320
       1.300000        0.002430        0.002430
       1.400000        0.010240        0.010240
       1.500000        0.031250        0.031250
       1.600000        0.077760        0.077760
       1.700000        0.168070        0.168070
       1.800000        0.327681        0.327680
       1.900000        0.590491        0.590490
       2.000000        1.000000        1.000000
press ENTER to continue...
       first deriv: 
           x            DDPOLY          actual
       0.100000        3.280500        3.280500
       0.200000        2.048000        2.048000
       0.300000        1.200500        1.200500
       0.400000        0.648000        0.648000
       0.500000        0.312500        0.312500
       0.600000        0.128000        0.128000
       0.700000        0.040500        0.040500
       0.800000        0.008000        0.008000
       0.900000        0.000501        0.000500
       1.000000        0.000000        0.000000
       1.100000        0.000500        0.000500
       1.200000        0.008001        0.008000
       1.300000        0.040499        0.040500
       1.400000        0.128001        0.128000
       1.500000        0.312500        0.312500
       1.600000        0.648000        0.648000
       1.700000        1.200500        1.200500
       1.800000        2.048001        2.048000
       1.900000        3.280502        3.280500
       2.000000        5.000000        5.000000
press ENTER to continue...
       second deriv: 
           x            DDPOLY          actual
       0.100000      -14.580000      -14.579999
       0.200000      -10.240001      -10.239999
       0.300000       -6.859999       -6.860000
       0.400000       -4.320000       -4.320000
       0.500000       -2.500000       -2.500000
       0.600000       -1.280001       -1.280000
       0.700000       -0.540001       -0.540000
       0.800000       -0.160001       -0.160000
       0.900000       -0.019996       -0.020000
       1.000000        0.000000        0.000000
       1.100000        0.019999        0.020000
       1.200000        0.160001        0.160000
       1.300000        0.539999        0.540000
       1.400000        1.280002        1.280000
       1.500000        2.500000        2.500000
       1.600000        4.319999        4.320000
       1.700000        6.860001        6.860002
       1.800000       10.240000       10.239998
       1.900000       14.580003       14.579998
       2.000000       20.000000       20.000000
press ENTER to continue...
       third deriv: 
           x            DDPOLY          actual
       0.100000       48.599998       48.600000
       0.200000       38.399998       38.399999
       0.300000       29.400002       29.399999
       0.400000       21.600000       21.600001
       0.500000       15.000000       15.000000
       0.600000        9.599993        9.599999
       0.700000        5.399999        5.400000
       0.800000        2.400000        2.400000
       0.900000        0.600008        0.600000
       1.000000        0.000000        0.000000
       1.100000        0.599997        0.600000
       1.200000        2.400002        2.400001
       1.300000        5.399997        5.399998
       1.400000        9.600004        9.599999
       1.500000       15.000000       15.000000
       1.600000       21.599998       21.600001
       1.700000       29.400003       29.400004
       1.800000       38.399994       38.399996
       1.900000       48.600002       48.599997
       2.000000       60.000000       60.000000
press ENTER to continue...
       fourth deriv: 
           x            DDPOLY          actual
       0.100000     -108.000015     -107.999997
       0.200000      -96.000023      -96.000001
       0.300000      -83.999985      -83.999999
       0.400000      -71.999985      -72.000003
       0.500000      -60.000000      -60.000000
       0.600000      -48.000011      -47.999997
       0.700000      -36.000000      -36.000001
       0.800000      -23.999998      -23.999999
       0.900000      -11.999994      -12.000003
       1.000000        0.000000        0.000000
       1.100000       11.999997       12.000003
       1.200000       24.000006       24.000006
       1.300000       35.999992       35.999994
       1.400000       48.000000       47.999997
       1.500000       60.000000       60.000000
       1.600000       72.000000       72.000003
       1.700000       84.000008       84.000006
       1.800000       95.999992       95.999994
       1.900000      108.000000      107.999997
       2.000000      120.000000      120.000000
press ENTER to continue...