» prob2a

pp1 = 

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


ans =

    0.0415         0   -0.0985    0.0003
   -0.1163    0.2490    0.3995    0.1353
    0.1163   -0.4487         0    1.0000
   -0.0415    0.2490   -0.3995    0.1353


pp2 = 

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


ans =

    0.0078   -0.0000    0.0029    0.0003
    0.0743    0.0235    0.0264    0.0111
   -0.0716    0.2465    0.2964    0.1353
   -0.2125    0.0316    0.5744    0.6065
    0.2125   -0.6060   -0.0000    1.0000
    0.0716    0.0316   -0.5744    0.6065
   -0.0743    0.2465   -0.2964    0.1353
   -0.0078    0.0235   -0.0264    0.0111


pp3 = 

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


ans =

    0.0074         0    0.0019    0.0003
    0.0198    0.0110    0.0074    0.0022
    0.0482    0.0407    0.0332    0.0111
    0.0647    0.1130    0.1101    0.0439
    0.0079    0.2100    0.2716    0.1353
   -0.1391    0.2219    0.4876    0.3247
   -0.2392    0.0132    0.6051    0.6065
   -0.1244   -0.3456    0.4389    0.8825
    0.1244   -0.5322    0.0000    1.0000
    0.2392   -0.3456   -0.4389    0.8825
    0.1391    0.0132   -0.6051    0.6065
   -0.0079    0.2219   -0.4876    0.3247
   -0.0647    0.2100   -0.2716    0.1353
   -0.0482    0.1130   -0.1101    0.0439
   -0.0198    0.0407   -0.0332    0.0111
   -0.0074    0.0110   -0.0074    0.0022