Build a function by combining a variable number of sub-functions

Hi,

I’m building an app to fit some data.

The fitting function can vary, and I’d like to have the possibility to use different combinations of basic functions, like Lorentzian, gaussian, damped harmonic oscillator…. In the example below, there are two of these functions (Lrz and DHO) and a multiplying factor (be) :

properties (Access = public)

nLrz, nLrzw, nDHO, T   % Lorz
end

methods (Access = private)

function nw=be(app,x,Temp)
kT=8.6173303e-2*Temp;
nw = 1/kT*x./(1-exp(-x/kT));
nw(isnan(nw))=1;
end

function fLrz = Lrz(app,P,x)
fLrz=(P(1)/pi*P(2)./(x.^2 + P(2)^2));        
end

function fDHO = DHO(app,P,x)
fDHO=P(1)/pi * 2*P(2) * P(3)^2 ./ ( (x.^2-P(3)^2).^2 + 4*(P(2) * x).^2 ) ;     
end
end

The number of the Lrz and DHO is also a variable (they typically range from 1 to 4). For example: Ftot = Lrz1 + Lrz2 + be*DHO (that is nLrz=2 and nDHO=1), that means that I’d like to have something like :

Ftot = @(pL1,pL2,pL1,x) Lrz(app,pL1,x) + Lrz(app,pL2,x) + be.*DHO(app,pD1,x)

As far I understood, loops are not suggested.

Based on the number of parameters, the app will produce a table where to enter the guess values of the (variable number of) parameters pL1,pL2,pD1, T,and so on

I am wondering which is the best way to enter the parameters in Ftot.

A possible choice is to have something like:

pL(1).I=10; % 1st Lrz

pL(1).G=2;

pL(2).I=1; % 2nd Lrz

pL(2).G=6;

pD(1).I=1; % 1st DHO

pD(1).G=1;

pD(1).E=8;

I am looking for some hints on the more efficient way to go on.

Thanks for your help!