Re: Interpolation vs. SplineFit
- To: mathgroup at smc.vnet.net
- Subject: [mg21927] Re: [mg21889] Interpolation vs. SplineFit
- From: Bojan Bistrovic <bojanb at physics.odu.edu>
- Date: Fri, 4 Feb 2000 02:54:53 -0500 (EST)
- Sender: owner-wri-mathgroup at wolfram.com
> > Hello- > > What is the difference between a Cubic SplineFit and Interpolation with > InterpolationOrder->3? In the documentation, Interpolation works by fitting > polynomials of the specified order over the data. This is also the concept > behind SplineFit. When I have compared the two functions, the Interpolation > function creates a "smoother" plot, however, it has some undesirable ripples. > SplineFit more accurately interpolates the physical realities of the data, but > cannot handle any data points outside the region of the original data set. I > would like to use Interpolation so that I can extrapolate beyond the original > data range (carefully, of course). > > Mostly, I'm interested in the differences in how SplineFit and Interpolation > create functions over the data. > > Thanks > > Matt Johnson > > Interpolation will always produce the function, and when I say function, I mean in mathematical sense: for each "x" there's ONE AND ONLY ONE f[x]; spline will fit it to a line in a plane, so for one "x" you can have more f[x]-es. Look at NumericalMath`SplineFit` for examples. Bojan -- ------------------------------------------------------------- Bojan Bistrovic, bojanb at physics.odu.edu Old Dominion University, Physics Department, Norfolk, VA -------------------------------------------------------------