title: Cubic Spline class for Obj C or C?
body: <p>I need to use natural cubic spline interpolation in an iPhone app.  Does anyone know of a class for Obj C or C that resembles this: 
  <a href="http://www.ee.ucl.ac.uk/~mflanaga/java/CubicSpline.html" rel="nofollow">http://www.ee.ucl.ac.uk/~mflanaga/java/CubicSpline.html</a></p>
  
  <p>"performing an interpolation within a one dimensional array of data points, y = f(x), using a cubic spline."</p>