Example (Using InputForm[ ])

This example should help you decipher the output of InputForm[ ].


  g={{1,2},{2,3},{3,6},{4,12}}


  fitg=SplineFit[g,Cubic]


  plot1=ParametricPlot[fitg[x],{x,0,3},PlotRange->All,
  	Compiled->False];


  InputForm[fitg]

Notice how the coefficients and variables (x-h)/a work.
The form is {{h, a, 0, 0}, {c0, c1, c2, c3}}
c0+c1((x-h)/a)+c2((x-h)/a)^2+c3((x-h)/a)^3.
For example, {{2, 1, 0, 0}, {3, 5/3, 1, 1/3}} means that the cubic between x=2 ands x=3 is
3+5/3 ((x-2)/1) + 1((x-2)/1)^2 + 1/3 ((x-2)/1)^3.


  g1[x_]:=2+2/3 (x-1)+1/3 (x-1)^3
  g2[x_]:=3+5/3 (x-2)+(x-2)^2+1/3 (x-2)^2
  g3[x_]:=6+14/3 (x-3)+2 (x-3)^2-2/3 (x-3)^3


  gspl[x_]:=If[x<=2,g1[x],
  				 If[x<=3,g2[x],
  					If[x<=4,g3[x]]
  				 ]
  			    ]


  plot2=Plot[gspl[x],{x,1,4}];


  Show[plot1,plot2];

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