» prob2b

pp1 = 

      form: 'pp'
    breaks: [-4 -2 0 2 4]
     coefs: [4x4 double]
    pieces: 4
     order: 4
       dim: 1


ans =

    0.0536         0   -0.2143         0
   -0.1429    0.3214    0.4286         0
    0.1429   -0.5357         0    1.0000
   -0.0536    0.3214   -0.4286         0


pp2 = 

      form: 'pp'
    breaks: [-4 -3 -2 -1 0 1 2 3 4]
     coefs: [8x4 double]
    pieces: 8
     order: 4
       dim: 1


ans =

    0.0309         0   -0.0309         0
   -0.1546    0.0928    0.0619         0
    0.5876   -0.3711   -0.2165         0
   -1.1959    1.3918    0.8041         0
    1.1959   -2.1959   -0.0000    1.0000
   -0.5876    1.3918   -0.8041         0
    0.1546   -0.3711    0.2165         0
   -0.0309    0.0928   -0.0619         0


pp3 = 

      form: 'pp'
    breaks: [1x17 double]
     coefs: [16x4 double]
    pieces: 16
     order: 4
       dim: 1


ans =

    0.0009         0   -0.0002         0
   -0.0047    0.0014    0.0005         0
    0.0177   -0.0056   -0.0016         0
   -0.0663    0.0210    0.0061         0
    0.2474   -0.0784   -0.0226         0
   -0.9234    0.2927    0.0845         0
    3.4462   -1.0924   -0.3154         0
   -4.8616    4.0770    1.1769         0
    0.0000   -3.2154    1.6077    1.0000
    4.8616   -3.2154   -1.6077    1.0000
   -3.4462    4.0770   -1.1769         0
    0.9234   -1.0924    0.3154         0
   -0.2474    0.2927   -0.0845         0
    0.0662   -0.0784    0.0226         0
   -0.0174    0.0209   -0.0061         0
    0.0035   -0.0052    0.0017         0