Fitting data smoothly in Matlab and Gnuplot

Question

I would like to find a better way of fitting my data. Right now, that it the best I can do, see Figure.

It's done using Gnuplot and smooth when plotting. However, as you might see in the Figure, 'csplines' seems to be the most acuarate technique, but it is not enough. It is fine in the first half of the graph, but not good at all in the second half. The real data, just 4 points in 'x=[1,2,4,8]', is marked in 'Line 1'. Is there a better way of doing it using Gnuplot?

What about Matlab (or even other tools)? How can I easily create a smooth curve connecting a few points?

Answer 1

Why not have a look at the scipy interpolation documentation:

http://docs.scipy.org/doc/scipy/reference/tutorial/interpolate.html

There are plenty of schemes there which will help you plot your smoothed data using matplotib.

HTH