Interpolate within two data sets

Dear Root-Users

I do have two data sets, describing measurements at different energies, each data set contains a length(position) and an arbitrary value (of interest). The number of data points within these sets can be different (different positions as well).

I want to interpolate values at an energy in between these two. To use the Interpolator function I would basically need to create a third data set at an energy in between these two.

What I found so far: I could implement it in the following way: Use Interpolator class to interpolate data set A to get a fixed number of data points, do the same with data set B. Now call the Interpolator for every data point in A and B to get the new data set. This sounds quite inefficient to me. Is there a better way to do that?

Example (I just made up the values)
A(@100MeV)

length	value
0.15	23
0.25	26
0.35	43
0.45	44
0.55	50

B(@200MeV)
length	value
0.17	24
0.27	27
0.37	44

Cheers,
Hermann

-- 
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DI Hermann Fuchs
Div. Medical Radiation Physics
Department of Radiotherapy
Med. Univ. Vienna / AKH Vienna
Währinger Gürtel 18-20
A-1090 Wien

Tel.  + 43 / 1 / 40 400 7271
Mail. hermann.fuchs_at_meduniwien.ac.at