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Curve fitting with superposition of waves

Thu, 03/16/2017 - 03:54 am

I want to do curve fitting to an experimental wave.
I don't want to use a mathematical expression but just a superposition of already exisiting waves, i.e. something like
wave0 = alpha * wave1 + beta * wave2
where alpha and beta are the fitting parameters.

The wave to be described with this fit and the components wave1/wave2 all have the same x values.

Is there an easy way to do this with IGOR?

HJDrescher

This is a sample function I used for two components, an offset and shifts:
Make sure to use the all-at-once version of the fitting function. The use of MultiThread depends on the number of data points in your waves.

Function CalorimetryOdd(wc,wy,wx):Fitfunc
Wave wc, wy, wx
Wave LO=root:NAC:Experiment:FitLaserReferenceOdd, RO=root:NAC:Experiment:FitRadiationOdd
    MultiThread wy=wc[0]+wc[1]*LO(x-wc[2])+wc[3]*RO(x-wc[4])
End

March 16, 2017 at 04:25 am - Permalink