Spline Toolbox

Using the Spline Fits

If f is one of these splines cs, ch, or sp so constructed, then, as we saw already, it can be displayed by the statement

• fnplt(f) 
  

Its value a at a is given by the statement

• fnval(f,a);
  

Its second derivative is constructed by the statement

• DDf = fnder(fnder(f));
  

or by the statement

• DDf = fnder(f,2);
  

Its definite integral over the interval [a..b] is supplied by the statement

• [1 -1]*fnval(fnint(f),[b;a]);
  

and the difference between the spline in cs and the one in ch can be computed as

• fncmb(cs,'-',sp);
  

Least Squares

Vector-Valued Functions