import numpy as np from lmfit.models1d import GaussianModel, LorentzianModel, VoigtModel import matplotlib.pyplot as plt x = np.linspace(0, 10, 101) sca = 1./(2.0*np.sqrt(2*np.pi)) noise = 5e-2*np.random.randn(len(x)) dat = 2.60 -0.04*x + 7.5 * np.exp(-(x-4.0)**2 / (2*0.35)**2) + noise mod = GaussianModel(background='linear') # mod = VoigtModel(background='linear') # mod = LorentzianModel(background='linear') mod.guess_starting_values(dat, x) plt.plot(x, dat) # initial guess plt.plot(x, mod.model(x=x) + mod.calc_background(x), 'r+') mod.fit(dat, x=x) print mod.fit_report() # best fit plt.plot(x, mod.model(x=x) + mod.calc_background(x)) plt.show()
model = VoigtModel(background='linear') # get default starting values, but then alter them model.guess_starting_values(y, x=x) model.params['amplitude'].value = 2.0 init_fit = model.model(x=x) # the actual fit model.fit(y, x=x) print model.fit_report(min_correl=0.25) vfit = model.model(x=x) mod2 = GaussianModel(background='linear') mod2.fit(y, x=x) gfit = mod2.model(x=x) print mod2.fit_report(min_correl=0.25) print 'Voigt Sum of Squares: ', ((vfit - y)**2).sum() print 'Gaussian Sum of Squares: ', ((gfit - y)**2).sum() plt.plot(x, vfit, 'r-') plt.plot(x, gfit, 'b-') plt.plot(x, y, 'bo') plt.show()
import numpy as np from lmfit.models1d import GaussianModel import matplotlib.pyplot as plt data = np.loadtxt('model1d_gauss.dat') x = data[:, 0] y = data[:, 1] model = GaussianModel() # background='linear' # model.guess_starting_values(y, x, negative=False) # model.params['bkg_offset'].value=min(y) init_fit = model.model(x=x) + model.calc_background(x) model.fit(y, x=x) print model.fit_report() final_fit = model.model(x=x) plt.plot(x, y) plt.plot(x, init_fit) plt.plot(x, final_fit) plt.show()
import numpy as np from lmfit.models1d import GaussianModel import matplotlib.pyplot as plt data = np.loadtxt('model1d_gauss.dat') x = data[:, 0] y = data[:, 1] model = GaussianModel() model.guess_starting_values(y, x=x) # model.params['amplitude'].value=6.0 init_fit = model.model(x=x) model.fit(y, x=x) print model.fit_report(min_correl=0.25) final_fit = model.model(x=x) plt.plot(x, final_fit, 'r-') plt.plot(x, init_fit, 'k--') plt.plot(x, y, 'bo') plt.show()