Example: Lorentzian model

The example here will use a custom-built Lorentzian shape line with one and two modes and fit them using the fit_curve_model tool.

The complete code can be found here.

Load modules

using Plots, LaTeXStrings
pyplot()
using ThinFilmsTools

X-axis length

Let's define now the x-axis span:

x = -10:0.01:10
len_x = length(x)

Lorentzian: 1 peak

seed1 = [[0.0], # offset
         [15.0, 0.0, 0.5]] # peak

Generate data

We generate some data using the Lorentzian model. For this, we use the same function to model, with some parameters:

y_data = Utils.lorentzian(x, seed1) .+ randn(len_x)

Optimise

We run the optimiser and plot the results:

sol = fit_curve_model(:lorentzian, x, y_data, seed1)
plot(FitSpectrum(), x, y_data, sol.ymodel)
gui()

Lorentzian: 2 peaks

Now let's try the same thing, but with one more peak:

seed2 = [[0.0], # offset
         [15.0, -1.0, 0.5], # first peak
         [30.0, 1.0, 0.5]] # second peak
y_data = Utils.lorentzian(x, seed2) .+ randn(len_x)
sol = fit_curve_model(:lorentzian, x, y_data, seed2)
plot(FitSpectrum(), x, y_data, sol.ymodel)
gui()