Пример #1
0
    def gauss(x, y):
        print(
            'Selecione a regiao do fit gaussiano quantas vezes for necessario')
        l1, l2 = fit_gauss(x, y)
        index1 = np.where(abs(x - l1) == min(abs(x - l1)))[0]
        index1 = np.int(index1)
        index2 = np.where(abs(x - l2) == min(abs(x - l2)))[0]
        index2 = np.int(index2)
        print(index1, index2)
        x1 = x[index1:index2]
        y1 = y[index1:index2]
        mod = GaussianModel()
        pars = mod.guess(y1, x=x1)
        out = mod.fit(y1, pars, x=x1)
        xgauss = copy.copy(x1)
        ygauss = copy.copy(out.best_fit)
        #-#######
        x0 = x[0:index1]
        y0 = np.zeros(len(y[0:index1]))
        x2 = x[index2:]
        y2 = np.zeros(len(y[index2:]))
        x1 = np.append(x0, x1)
        x1 = np.append(x1, x2)
        y1 = np.append(y0, out.best_fit)
        y1 = np.append(y1, y2)
        print(out.fit_report(min_correl=0.25))

        mod = GaussianModel()
        pars = mod.guess(y1, x=x1)
        out = mod.fit(y1, pars, x=x1)

        #-#######

        return x1, out.best_fit, xgauss, ygauss
Пример #2
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    def twoPeakGaussianFit(self):
        try:
            nRow, nCol = self.dockedOpt.fileInfo()

            self.binFitData = np.zeros((nRow, 0))
            self.TwoPkGausFitData = np.zeros((nCol, 12))  # Creates the empty 2D List
            for j in range(nCol):
                yy1 = []
                yy2 = []
                yy = self.dockedOpt.TT[:, j]
                i = 0
                for y in yy:
                    if i < len(yy) / 2:
                        yy1.append(y)
                    else:
                        yy2.append(y)
                    i += 1

                xx = np.arange(0, len(yy))
                xx1 = np.arange(0, len(yy) / 2)
                xx2 = np.arange(len(yy) / 2, len(yy))
                x1 = xx[0]
                x2 = xx[-1]
                y1 = yy[0]
                y2 = yy[-1]
                m = (y2 - y1) / (x2 - x1)
                b = y2 - m * x2

                mod1 = GaussianModel(prefix='p1_')

                mod2 = GaussianModel(prefix='p2_')

                pars1 = mod1.guess(yy1, x=xx1)
                pars2 = mod2.guess(yy2, x=xx2)

                mod = mod1 + mod2 + LinearModel()
                pars = pars1 + pars2

                pars.add('intercept', value=b, vary=True)
                pars.add('slope', value=m, vary=True)
                out = mod.fit(yy, pars, x=xx, slope=m)

                self.TwoPkGausFitData[j, :] = (out.best_values['p1_amplitude'], 0, out.best_values['p1_center'],
                                                       0, out.best_values['p1_sigma'], 0,
                                                       out.best_values['p2_amplitude'], 0, out.best_values['p2_center'],
                                                       0, out.best_values['p2_sigma'], 0)

                # Saves fitted data of each fit
                fitData = out.best_fit
                binFit = np.reshape(fitData, (len(fitData), 1))
                self.binFitData = np.concatenate((self.binFitData, binFit), axis=1)

                if self.continueGraphingEachFit == True:
                    self.graphEachFitRawData(xx, yy, out.best_fit, 'G')

            return False
        except Exception as ex:
            qtWidgets.QMessageBox.warning(self.myMainWindow, "Error", "Please make sure the guesses are realistic when fitting."
                                                            "\n\nException: " + str(ex))
            return True
Пример #3
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def test_guess_requires_x():
    """Regression test for GH #747."""
    x = np.arange(100)
    y = np.exp(-(x - 50)**2 / (2 * 10**2))

    mod = GaussianModel()
    msg = r"guess\(\) missing 1 required positional argument: 'x'"
    with pytest.raises(TypeError, match=msg):
        mod.guess(y)
Пример #4
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def fit_gaussians_to_emission_lines(spectra, centers, x=None, verbose=False):
    # First, sort out x
    if x is None: x = np.arange(spectra.shape[0])

    # we know which peaks to calibrate off, we still need to fit a Gaussian to them so we can get the exact peak position instead of just the highest pixel
    pars = []
    Model = None

    gaussmodel = GaussianModel(prefix='f{:}_'.format(0))
    pars = gaussmodel.guess(x, spectra)
    pars['f{:}_center'.format(0)].set(vary=True,
                                      value=centers[0],
                                      min=centers[0] - 2,
                                      max=centers[0] + 2)
    pars['f{:}_amplitude'.format(0)].set(
        vary=True,
        value=0.5,
    )
    pars['f{:}_sigma'.format(0)].set(vary=True, value=2, min=0.9, max=5)

    for i in range(1, centers.shape[0]):
        gaussmodel_ = GaussianModel(prefix='f{:}_'.format(i))
        pars_ = gaussmodel_.guess(x, spectra)
        pars_['f{:}_center'.format(i)].set(vary=True,
                                           value=centers[i],
                                           min=centers[i] - 5,
                                           max=centers[i] + 5)
        pars_['f{:}_amplitude'.format(i)].set(vary=True, value=0.5)
        pars_['f{:}_sigma'.format(i)].set(vary=True, value=2, min=0.9, max=5)
        gaussmodel = gaussmodel + gaussmodel_
        pars = pars + pars_
    out = gaussmodel.fit(spectra, pars, x=x, method='powell')

    if verbose:
        print('Gaussians fit to spectra:')
        print(out.fit_report())

    centers = np.array([
        float(out.params['f{:}_center'.format(i)].value)
        for i in range(len(centers))
    ])
    aplitudes = np.array([
        float(out.params['f{:}_amplitude'.format(i)].value)
        for i in range(len(centers))
    ])
    sigmas = np.array([
        float(out.params['f{:}_sigma'.format(i)].value)
        for i in range(len(centers))
    ])

    return centers, aplitudes, sigmas, out
Пример #5
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def fit_gauss(graph=False, cdf=False, residuals=False):
    xranges, yranges, xrange, yrange, filename1, dat1 = range_to_list()
    FitVals = DataFrame(columns=['Sigma', 'Center', 'Amplitude', 'FWHM', 'Height', 'Intercept', 'Slope', 'ChiSq',
                                 'RedChiSq', 'Akaike', 'Bayesian'])
    for i in range(0, len(xranges)):
        mdl = GaussianModel()
        params = mdl.guess(data=yranges[i], x=xranges[i])
        result = mdl.fit(yranges[i], params, x=xranges[i])
        print(result.fit_report())
        FitVals.at[i, 'Sigma'] = ufloat(result.params['sigma'].value, result.params['sigma'].stderr)
        FitVals.at[i, 'Center'] = ufloat(result.params['center'].value, result.params['center'].stderr)
        FitVals.at[i, 'Amplitude'] = ufloat(result.params['amplitude'].value, result.params['amplitude'].stderr)
        FitVals.at[i, 'FWHM'] = ufloat(result.params['fwhm'].value, result.params['fwhm'].stderr)
        FitVals.at[i, 'Height'] = ufloat(result.params['height'].value, result.params['height'].stderr)
        FitVals.at[i, 'ChiSq'] = result.chisqr
        FitVals.at[i, 'RedChiSq'] = result.redchi
        FitVals.at[i, 'Akaike'] = result.aic
        FitVals.at[i, 'Bayesian'] = result.bic
        if graph:
            plt.plot(xranges[i], yranges[i], '.', markerfacecolor="None", color='#050505',
                     mew=1.4, ms=1, antialiased=True, label='Data from frequency sweep')
            plt.plot(xranges[i], result.best_fit, lw=2, label='Gaussian + Line fit')
            plt.legend()
            plt.xlabel('Frequency (Hz)')
            plt.ylabel('Variance (a.u)')
            fullscreen()
            plt.show()
        if cdf:
            values, base = np.histogram(yranges[i], bins='auto')
            cumulative = np.cumsum(values)
            plt.plot(base[:-1], cumulative)
            plt.plot(base[:-1], values)
            fullscreen()
            plt.show()
        if residuals:
            values, base = np.histogram(result.residual, bins='fd')
            cumulative = np.cumsum(values)
            # plt.plot(xranges[i], result.residual)
            # plt.plot(base[:-1], cumulative, '.')
            mdl2 = GaussianModel()
            params2 = mdl2.guess(data=values, x=base[:-1])
            model2 = mdl2
            result2 = model2.fit(values, params2, x=base[:-1])
            plt.plot(base[:-1], values, '.')
            plt.plot(base[:-1], result2.best_fit)
            plt.xlabel('Residuals')
            plt.ylabel('Counts')
            fullscreen()
            plt.show()
Пример #6
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def GaussCalc(x, y, x1, y1):
    y = removerBackground(y)
    y1 = removerBackground(y1)

    mod = GaussianModel()
    pars = mod.guess(y, x=x)
    out = mod.fit(y, pars, x=x)

    mod = GaussianModel()
    pars1 = mod.guess(y1, x=x1)
    out1 = mod.fit(y1, pars1, x=x1)

    center = out.best_values['center']
    sigma = Decon_Gau(out.best_values['sigma'], out1.best_values['sigma'])
    return ScherrerEquation(sigma, center)
Пример #7
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def fit(les_x_init, les_y_init, remove):
    les_x = []
    les_y = []
    for i in range(len(les_x_init)):
        if les_x_init[i] not in remove:
            les_x.append(les_x_init[i])
            les_y.append(les_y_init[i])
    x = scipy.asarray(les_x)
    y = scipy.asarray(les_y)
    gmod = GaussianModel()
    param = gmod.guess(y, x=x)
    amplitude = param['amplitude'].value
    center = param['center'].value
    sigma = param['sigma'].value
    the_fit = gmod.fit(y, x=x, amplitude=amplitude, center=center, sigma=sigma)
    best_res = the_fit.chisqr
    amplitude = the_fit.params['amplitude'].value
    center = the_fit.params['center'].value
    sigma = the_fit.params['sigma'].value
    best_sol = [amplitude, center, sigma]
    y_fit = []
    for i in range(len(les_x_init)):
        y_fit.append(
            gmod.eval(x=les_x_init[i],
                      amplitude=amplitude,
                      center=center,
                      sigma=sigma))
    return [best_sol, best_res, y_fit]
Пример #8
0
def GaussConst(signal, guess):
    
    if guess == False:
        return [0, 0, 0]
    else:
        amp, centre, stdev, offset = guess
        
        data = np.array([range(len(signal)), signal]).T
        X = data[:,0]
        Y = data[:,1]

        gauss_mod = GaussianModel(prefix='gauss_')
        const_mod = ConstantModel(prefix='const_')
        
        #pars = lorentz_mod.make_params(amplitude=amp, center=centre, sigma=stdev / 3.)
        #lorentz_mod.set_param_hint('sigma', value = stdev / 3., min=0., max=stdev)
        
        pars = gauss_mod.guess(Y, x=X, center=centre, sigma=stdev / 3., amplitude=amp)
        #pars += step_mod.guess(Y, x=X, center=centre)
        pars += const_mod.guess(Y, x=X)
        
        pars['gauss_sigma'].vary = False
        mod = gauss_mod + const_mod
        result = mod.fit(Y, pars, x=X)
        # write error report
        #print result.fit_report()
        fwhm = result.best_values['gauss_sigma'] * 2.3548

        
    return X, result.best_fit, result.redchi, fwhm
Пример #9
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def NewFit2(amp1, amp2, mu1, mu2, sig1, sig2, x, y):

    '=========================================='
    'Define the first gaussian'
    gauss1 = GaussianModel(prefix='g1_')  # Model first as a gaussian
    pars = gauss1.guess(y, x=x)  # Make a gautomatic guess of the parameters

    'Set the Parameters values'
    pars['g1_center'].set(mu1, vary=True)
    pars['g1_sigma'].set(sig1, vary=True)
    pars['g1_amplitude'].set(amp1, vary=True)

    '==========================================='
    'Define the second Gaussian'
    gauss2 = GaussianModel(prefix='g2_')
    pars.update(
        gauss2.make_params())  #update the parameter list with another gaussian

    pars['g2_center'].set(mu2, vary=True)
    pars['g2_sigma'].set(sig2, vary=True)
    pars['g2_amplitude'].set(amp2, vary=True)

    '==========================================='

    'Make the model as the sum of gaussians'
    mod = gauss1 + gauss2

    'Fit and print the data'
    out = mod.fit(y, pars, x=x)
    print(out.fit_report(min_correl=0.5))
    plt.plot(x, out.best_fit, 'r-', linewidth=1.50)
    plt.show()
    return pars
Пример #10
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def find_fraunhofer_center(field: np.ndarray,
                           ic: np.ndarray,
                           debug: bool = False) -> float:
    """Extract the field at which the Fraunhofer is centered.

    Parameters
    ----------
    field : np.ndarray
        1D array of the magnetic field applied of the JJ.
    ic : np.ndarray
        1D array of the JJ critical current.

    Returns
    -------
    float
        Field at which the center of the pattern is located.

    """
    max_loc = np.argmax(ic)
    width, *_ = peak_widths(ic, [max_loc], rel_height=0.5)
    width_index = int(round(width[0] * 0.65))
    subset_field = field[max_loc - width_index:max_loc + width_index + 1]
    subset_ic = ic[max_loc - width_index:max_loc + width_index + 1]
    model = GaussianModel()
    params = model.guess(subset_ic, subset_field)
    out = model.fit(subset_ic, params, x=subset_field)

    if debug:
        plt.figure()
        plt.plot(field, ic)
        plt.plot(subset_field, out.best_fit)
        plt.show()

    return out.best_values["center"]
Пример #11
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    def refine_energies(self,
                        frame_width: int = 20) -> List[Tuple[float, Any]]:
        """
        Refine energy locations using curve fitting. For every peak in `.energies`, a small slice of the data around it is curve fitted to a gaussian and the center used as the refined energy location.
        
        Will set the property `.refined_energies` equal to function output

        Note: The detector energy channel is a `float` here

        Parameters:
            frame_width (int): The width of the slice of data around the peak used for curve fitting

        Returns:
            (List[Tuple[float, Any]]): List of energy locations as tuple (detector energy channel, actual energy)
        """
        model = GaussianModel()
        refined = []
        for energy in self.energies:
            domain = (int(max(energy[0] - frame_width / 2, 0)),
                      int(
                          min(energy[0] + frame_width / 2,
                              self.data.shape[0] - 1)))
            frame = self.data[domain[0]:domain[1]]
            pars = model.guess(frame, x=np.arange(0, 20))
            out = model.fit(frame, pars, x=np.arange(0, 20))
            refined.append((out.params["center"].value + domain[0], energy[1]))

        self.refined_energies = refined
        self.polynomial_coefficients = None
        return refined
Пример #12
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def test_2gaussians():

  x = np.linspace(0.0, 10.0, num=1000)
  y = gaussian(x, -1, 3, 0.75) + gaussian(x, -0.5, 5, 0.8) + np.random.normal(0, 0.01, x.shape[0])

  gauss1  = GaussianModel(prefix='g1_')
  
  pars = gauss1.guess(y, x=x)
  pars['g1_amplitude'].set(-0.9)
  pars['g1_center'].set(2.5)
  pars['g1_sigma'].set(0.5)

  gauss2  = GaussianModel(prefix='g2_')
  pars.update(gauss2.make_params())
  pars['g2_amplitude'].set(-0.4)
  pars['g2_center'].set(5)
  pars['g2_sigma'].set(0.5)

  mod = gauss1 + gauss2

  init = mod.eval(pars, x=x)

  plt.plot(x, y)
  plt.plot(x, init, 'k--')

  out = mod.fit(y, pars, x=x)

  print(out.fit_report(min_correl=0.5))

  plt.plot(x, out.best_fit, 'r-')
  plt.show()
Пример #13
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    def gaussian_model(self):
        composite_model = None
        composite_pars = None

        x, y = self.background_correction()

        for i in range(self.num_of_gaussians):

            model = GaussianModel(prefix='g' + str(i + 1) + '_')

            if composite_pars is None:
                composite_pars = model.guess(y, x=x)
#                 composite_pars = model.make_params()

            else:
                composite_pars.update(model.make_params())

            if composite_model is None:
                composite_model = model
            else:
                composite_model += model

        result = composite_model.fit(y,
                                     composite_pars,
                                     x=x,
                                     nan_policy='propagate')
        return result
Пример #14
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def gaussian(x, y):

	# Gaussian fit to a curve

    x_shifted = x - x.min() # Shifting to 0    
    y_shifted = y - y.min() # Shifting to 0    
    mod = GaussianModel() # Setting model type
    pars = mod.guess(y_shifted, x=x_shifted) # Estimating fit
    out = mod.fit(y_shifted, pars, x=x_shifted) # Fitting fit
    print(out.fit_report(min_correl=0.25)) # Outputting best fit results
    #print("Gaussian FWHM = ", out.params['fwhm'].value) # Outputting only FWHM
    out.plot() # Plotting fit
    
    
    std = np.std(x_shifted)
    mux = np.mean(x_shifted)
    h_y = np.max(out.best_fit)
    #print(std, mux, h_y)
    
    y_x = h_y/2
    
    x_i = mux - np.sqrt(2*(std**2)*
                    np.log((np.sqrt(2*np.pi)*y_x*std)/
                          (h_y)))
    
    x_f = mux + np.sqrt(2*(std**2)*
                    np.log((np.sqrt(2*np.pi)*y_x*std)/
                          (h_y)))  
    
    fwhm = x_f-x_i
    print(x_i, x_f, fwhm)
Пример #15
0
    def fit_and_plot_scan(self):
        #        self.ui.result_textBrowser.append("Starting Scan Fitting")
        print("Starting Scan Fitting")

        try:
            """Define starting and stopping wavelength values here"""
            start_nm = int(self.ui.start_nm_spinBox.value())
            stop_nm = int(self.ui.stop_nm_spinBox.value())

            ref = self.bck_file
            index = (ref[:, 0] > start_nm) & (ref[:, 0] < stop_nm)

            x = self.wavelengths
            x = x[index]

            data_array = self.intensities

            result_dict = {}

            for i in range(data_array.shape[0]):

                y = data_array[i, index]  # intensity
                yref = ref[index, 1]

                y = y - yref  # background correction
                y = y - np.mean(
                    y[(x > start_nm)
                      & (x < start_nm + 25)])  # removing any remaining bckgrnd

                gmodel = GaussianModel(prefix='g1_')  # calling gaussian model
                pars = gmodel.guess(y,
                                    x=x)  # parameters - center, width, height
                result = gmodel.fit(y, pars, x=x, nan_policy='propagate')
                result_dict["result_" + str(i)] = result

#            self.ui.result_textBrowser.append("Scan Fitting Complete!")
            print("Scan Fitting Complete!")

            filename = QtWidgets.QFileDialog.getSaveFileName(self)
            pickle.dump(result_dict,
                        open(filename[0] + "_fit_result_dict.pkl", "wb"))

            #            self.ui.result_textBrowser.append("Data Saved!")
            print("Data Saved!")

        except Exception as e:
            self.ui.result_textBrowser2.append(str(e))
            pass


#        self.ui.result_textBrowser.append("Loading Fit Data and Plotting")
        print("Loading Fit Data and Plotting")
        try:
            self.fit_scan_file = pickle.load(
                open(filename[0] + "_fit_result_dict.pkl", 'rb'))
            self.plot_fit_scan()

        except Exception as e:
            self.ui.result_textBrowser2.append(str(e))
            pass
Пример #16
0
    def gaussian_model_w_lims(self, peak_pos, sigma, min_max_range):
        #center_initial_guesses - list containing initial guesses for peak centers. [center_guess1, center_guess2]
        #sigma_initial_guesses - list containing initial guesses for sigma. [sigma1, sigma2]
        #min_max_range - list containing lists of min and max for peak center. [ [min1, max1], [min2, max2] ]

        x, y = self.background_correction()
        gmodel_1 = GaussianModel(prefix='g1_')  # calling gaussian model
        pars = gmodel_1.guess(y, x=x)  # parameters - center, width, height
        pars['g1_center'].set(peak_pos[0],
                              min=min_max_range[0][0],
                              max=min_max_range[0][1])
        pars['g1_sigma'].set(sigma[0])
        pars['g1_amplitude'].set(min=0)

        gmodel_2 = GaussianModel(prefix='g2_')
        pars.update(gmodel_2.make_params()
                    )  # update parameters - center, width, height
        pars['g2_center'].set(peak_pos[1],
                              min=min_max_range[1][0],
                              max=min_max_range[1][1])
        pars['g2_sigma'].set(sigma[1], min=composite_pars['g1_sigma'].value)
        pars['g2_amplitude'].set(min=0)

        gmodel = gmodel_1 + gmodel_2
        result = gmodel.fit(y, pars, x=x, nan_policy='propagate')
        return result
Пример #17
0
 def peakFit(self, x, y, model = 'gau', pi = None, di = None):
     ti = time.time()
     if pi:
         NumPeaks = len(pi)
         center = []
         fwhm = []
         amp = []
         numVal = len(x)
         for i in range(NumPeaks):
             pImin = pi[i]-di
             if pImin < 0:
                 pImin = 0
             pImax = pi[i] + di
             if pImax > (numVal-1):
                 pImax = numVal-1
             __y = y[pImin:pImax]
             __x = x[pImin:pImax]
             
             __y = np.power(10,__y/10) #np.array(y)- np.min(y)
             
             mod = GaussianModel()
             pars = mod.guess(__y, x=__x)
             out  = mod.fit(__y, pars, x=__x)
             center.append(out.best_values['center'])
             fwhm.append(out.best_values['sigma']*2.3548)
             amp.append(out.best_values['amplitude'])
         #print 'fit:', time.time()-ti
         return center, fwhm ,amp
Пример #18
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    def fit(self, xx, yy, fitType):
        xx = np.asarray(xx)
        yy = np.asarray(yy)
        print("XX", xx)
        print("YY", yy)
        print(len(xx))
        print(len(yy))
        print("XX", xx)
        x1 = xx[0]
        x2 = xx[-1]
        y1 = yy[0]
        y2 = yy[-1]
        m = (y2 - y1) / (x2 - x1)
        b = y2 - m * x2

        if fitType == "Gaussian":
            mod = GaussianModel()
        elif fitType == "Lorentzian":
            mod = LorentzianModel()
        else:
            mod = VoigtModel()

        pars = mod.guess(yy, x=xx, slope=m)
        print(pars)
        mod = mod + LinearModel()
        pars.add('intercept', value=b, vary=True)
        pars.add('slope', value=m, vary=True)
        out = mod.fit(yy, pars, x=xx)

        return out.best_fit
Пример #19
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def test_2gaussians():

    x = np.linspace(0.0, 10.0, num=1000)
    y = gaussian(x, -1, 3, 0.75) + gaussian(
        x, -0.5, 5, 0.8) + np.random.normal(0, 0.01, x.shape[0])

    gauss1 = GaussianModel(prefix='g1_')

    pars = gauss1.guess(y, x=x)
    pars['g1_amplitude'].set(-0.9)
    pars['g1_center'].set(2.5)
    pars['g1_sigma'].set(0.5)

    gauss2 = GaussianModel(prefix='g2_')
    pars.update(gauss2.make_params())
    pars['g2_amplitude'].set(-0.4)
    pars['g2_center'].set(5)
    pars['g2_sigma'].set(0.5)

    mod = gauss1 + gauss2

    init = mod.eval(pars, x=x)

    plt.plot(x, y)
    plt.plot(x, init, 'k--')

    out = mod.fit(y, pars, x=x)

    print(out.fit_report(min_correl=0.5))

    plt.plot(x, out.best_fit, 'r-')
    plt.show()
Пример #20
0
def lmfit_ngauss(x, y, *params):
    params = params[0]
    mods = []
    prefixes = []
    for i in range(0, len(params), 3):
        pref = "g%02i_" % (i / 3)
        gauss_i = GaussianModel(prefix=pref)

        if i == 0:
            pars = gauss_i.guess(y, x=x)
        else:
            pars.update(gauss_i.make_params())

        A = params[i]
        l_cen = params[i + 1]
        sigma = params[i + 2]

        pars[pref + 'amplitude'].set(A)
        pars[pref + 'center'].set(l_cen)
        pars[pref + 'sigma'].set(sigma)

        mods.append(gauss_i)
        prefixes.append(pref)

    mod = mods[0]

    if len(mods) > 1:
        for m in mods[1:]:
            mod += m

    print mod

    init = mod.eval(pars, x=x)
    out = mod.fit(y, pars, x=x)
    return mod, out, init
Пример #21
0
def lmfit_ngauss(x,y, *params):
  params = params[0]
  mods = []
  prefixes = []
  for i in range(0, len(params), 3):
    pref = "g%02i_" % (i/3)
    gauss_i = GaussianModel(prefix=pref)

    if i == 0:
      pars = gauss_i.guess(y, x=x)
    else:
      pars.update(gauss_i.make_params())

    A = params[i]
    l_cen = params[i+1]
    sigma = params[i+2]

    pars[pref+'amplitude'].set(A)
    pars[pref+'center'].set(l_cen)
    pars[pref+'sigma'].set(sigma)

    mods.append(gauss_i)
    prefixes.append(pref)

  mod = mods[0]

  if len(mods) > 1:
    for m in mods[1:]:
      mod += m

  print mod

  init = mod.eval(pars, x=x)
  out = mod.fit(y, pars, x=x)
  return mod, out, init
Пример #22
0
	def fit_to_gaussian(self, x, y):
		gmodel = GaussianModel()
		params = gmodel.guess(y, x=x)
		c = params['center'].value
		n = len(y)
		q3 = ((np.max(x) - c) / 2) + c
		min_x = np.min(x)
		q1 = ((params['center'].value - min_x) / 2) + min_x
		s = params['sigma'].value
		h = params['height'].value
		max_y = np.max(y)
		if np.max([h, max_y]) < 0.5:
			amp = 1 / n
			diff_h = 0.6 - h
			gmodel.set_param_hint('amplitude', value=amp)
			gmodel.set_param_hint('amplitude', max=amp * (1 + diff_h))
			gmodel.set_param_hint('amplitude', min=amp * diff_h)
		gmodel.set_param_hint('center', value=c)
		gmodel.set_param_hint('center', max=q3)
		gmodel.set_param_hint('center', min=q1)
		gmodel.set_param_hint('sigma', value=s)
		gmodel.set_param_hint('sigma', min=s / 2)
		gmodel.set_param_hint('sigma', max=s * 1.5)
		gmodel.set_param_hint('height', min=0.6)
		result = gmodel.fit(y, x=x)
		# gmodel.print_param_hints()
		report = result.fit_report()
		chi_re = re.compile(r'chi-square\s+=\s+([0-9.]+)')
		cor_re = re.compile(r'C\(sigma, amplitude\)\s+=\s+([0-9.-]+)')
		chis = np.float32(chi_re.findall(report))
		cors = np.float32(cor_re.findall(report))
		coeffs = np.concatenate((chis, cors))
		mse_model = self.assess_fit(y, result.init_fit - result.best_fit)
		mse_yhat = self.assess_fit(y, result.residual)
		return mse_model, mse_yhat, result, report, coeffs
Пример #23
0
    def _fit_gauss(xval, yval):

        model = GaussianModel()
        result = model.fit(yval, model.guess(yval, x=xval,
                           amplitude=np.max(yval)), x=xval)

        return result
Пример #24
0
def gauss_peak_fit(energy_data, cnts_data, energy_spectrum, channel_width):
    '''
    spectrum_gauss_fit takes an input spectrum and finds the peaks of the
    spectrum and fits a gaussian curve to the photopeaks and returns the
    amplitude and sigma of the gaussian peak.
    Make sure the spectrum is calibrated first.

    sigma_list, amplitude_list = spectrum_gauss_fit(energy_data, cnts_data, energy_spectrum, channel_width)

    energy_data: .energies_kev that has been calibrated from becquerel
    cnts_data: .cps_vals from becquerel spectrum
    energy_spectrum: an array of gamma energies generated from gamma_energies
    channel_width: width of the peak for analysis purposes
    '''
    sigma_list = []
    amplitude_list = []
    for erg in energy_spectrum:
        x_loc = list(
            filter(lambda x: (erg - 3) < energy_data[x] < (erg + 3),
                   range(len(energy_data))))
        x_loc_pk = range(int(x_loc[0] - 5), int(x_loc[0] + 5))
        pk_cnt = np.argmax(cnts_data[x_loc_pk])
        ch_width = range(int(x_loc_pk[pk_cnt] - channel_width),
                         int(x_loc_pk[pk_cnt] + channel_width))

        calibration = energy_data[ch_width]
        real_y_gauss = cnts_data[ch_width]
        x = np.asarray(calibration)
        real_y = np.asarray(real_y_gauss)

        mod_gauss = GaussianModel(prefix='g1_')
        line_mod = LinearModel(prefix='line')
        pars = mod_gauss.guess(real_y, x=x)
        pars.update(line_mod.make_params(intercept=real_y.min(), slope=0))
        pars.update(mod_gauss.make_params())
        pars['g1_center'].set(x[np.argmax(real_y)], min=x[np.argmax(real_y)]\
        - 3)
        pars['g1_sigma'].set(3, min=0.25)
        pars['g1_amplitude'].set(max(real_y), min=max(real_y) - 10)
        mod = mod_gauss + line_mod
        out = mod.fit(real_y, pars, x=x)

        #print("The amplitude sum is %0.2f" % sum(real_y))
        gauss_x = []
        gauss_y = []
        parameter_list_1 = []
        real_y_gauss = []
        #print(out.fit_report(min_correl=10))
        sigma = out.params['g1_sigma'].value
        amplitude = out.params['g1_amplitude'].value
        sigma_list.append(sigma)
        amplitude_list.append(amplitude)
        fit_params = {}

        #gauss_fit_parameters = [out.params[key].value for k in out.params]
        #print(key, "=", out.params[key].value, "+/-", out.params[key].stderr)
        gauss_fit_parameters = []

    return sigma_list, amplitude_list
def get_plume_gaussian_model(dat, img_width):
    '''returns a single gaussian fit for the pd series provided
    dat = horizontal row of plume time average df'''
    mod = GaussianModel()
    pars = mod.guess(dat, x=img_width)  # guesses starting value for gaussian
    out = mod.fit(dat, pars, x=img_width)  # finds best fit of gaussian

    return out
def fit_s21mag(x_val, y_val):
    peak = GaussianModel()
    offset = ConstantModel()
    model = peak + offset
    pars = offset.make_params(c=np.median(y_val))
    pars += peak.guess(y_val, x=x_val, amplitude=-0.5)
    result = model.fit(y_val, pars, x=x_val)
    return result
Пример #27
0
def fitSimpleHist(array,
                  title='E5XX',
                  nbins=25,
                  xlabel='mytit',
                  verbose=False,
                  savedir=None,
                  fileappendix='',
                  ax=None):
    """ Simple Gaussian fit to an array of datapoints. Output can be saved to file if wanted 
    Input Argument:
        array        -- np.array of input points
        title        -- title of graph. Will also be the filename
        nbins        -- number of histogram bins
        xlabel       -- label on x-axis
        verbose      -- T/F print the fit report
        savedir      -- Directory to save output to, if not specified nothing will be saved. Suggest os.getcwd() or '.'
        fileappendix -- will add "_fileappendix" to the filename specified by title.
    """
    gausfit = GaussianModel()
    if (ax == None):
        fig, ax = plt.subplots(figsize=(15, 3), nrows=1, ncols=1)
    redarray = array[array >= (array.mean() - 5 * array.std()
                               )]  # and array<= (array.mean()+ 5*array.std())]
    n, bins, patches = ax.hist(
        redarray[redarray <= array.mean() + 5 * array.std()], nbins)
    cbins = np.zeros(len(bins) - 1)
    for k in (range(0, len(bins) - 1)):
        cbins[k] = (bins[k] + bins[k + 1]) / 2
    pars = gausfit.guess(n, x=cbins)
    fitresult = gausfit.fit(n, pars, x=cbins)
    if (verbose):
        print(fitresult.fit_report())
    ax.plot(cbins, fitresult.best_fit, 'r-', linewidth=2)
    mean = fitresult.best_values['center']
    fwhm = 2.35 * fitresult.best_values['sigma']
    textstring = ' Mean : ' + '{:4.3f}'.format(mean) + '\n'
    textstring += ' FWHM : ' + '{:4.3f}'.format(fwhm)
    props = dict(boxstyle='round', facecolor='wheat', alpha=0.5)
    ax.text(0.05,
            0.95,
            textstring,
            transform=ax.transAxes,
            fontsize=14,
            verticalalignment='top',
            bbox=props)
    ax.set_xlabel(xlabel)
    ax.set_ylabel('Frequency')
    ax.set_title(title)
    if savedir != None:
        filename = os.path.join(savedir, title)
        if (fileappendix != ''):
            filename += '_' + fileappendix
        filename += '.png'
        plt.savefig(filename, dpi=200, bbox_inches='tight')

#   plt.show()
#   return
    return fitresult
 def fit_gaussian(self, array_x, array_y, figure_number):
     mod = GaussianModel()
     pars = mod.guess(array_y, x=array_x)
     out = mod.fit(array_y, pars, x=array_x)
     self.sigma_temp = out.params['sigma'].value
     self.amplitude_temp = out.params['amplitude'].value
     self.center_temp = out.params['center'].value
     self.plot_fit_function(array_x, figure_number)
     return self.sigma_temp, self.amplitude_temp, self.center_temp
Пример #29
0
 def gaussian_model_w_lims(self, peak_pos, sigma, min_max_range):
     x, y = self.background_correction()
     gmodel = GaussianModel(prefix='g1_')  # calling gaussian model
     pars = gmodel.guess(y, x=x)  # parameters - center, width, height
     pars['g1_center'].set(peak_pos,
                           min=min_max_range[0],
                           max=min_max_range[1])
     pars['g1_sigma'].set(sigma)
     result = gmodel.fit(y, pars, x=x, nan_policy='propagate')
     return result  #770 760 780   sigma 15
Пример #30
0
 def fit_gaussian(self):
     mod = GaussianModel()
     pars = mod.guess(self.result[:, 1], x=self.result[:, 0])
     out = mod.fit(self.result[:, 1], pars, x=self.result[:, 0])
     self.sigma = out.params['sigma'].value
     self.amp = out.params['amplitude'].value
     self.center = out.params['center'].value
     print('sigma:' + str(self.sigma), 'amp:' + str(self.amp), 'center' + str(self.center))
     self.plot_fit_function(1)
     return self.sigma, self.amp, self.center
Пример #31
0
def bootg(data,
          flareinds,
          ind,
          st=40,
          end=130,
          indiv=False,
          num=100,
          offset=0):
    '''Bootstrap gaussian fit for one flare.
    Inputs:
    -------
    data: sog4
    flareinds: flareinds
    ind: index of flare to bootstrap (used to get inds from flareinds if indiv False)
    st: used as start index if indiv True
    end: used as end index if indiv True
    indiv: use individual index arguments (st,end) rather than ind, which then references flareinds (default False)
    num: number of bootstrap iterations (default 100)
    offset: gaussian vertical offset
    
    Outputs:
    --------
    bsouts: list of bootstrap model results
    bsfits: DataFrame with parameters from each bootstrap iteration 
    '''
    if indiv:
        ind1, ind2 = st, end
    else:
        ind1, ind2 = flareinds[ind][0], flareinds[ind][1]
    bsouts = []
    for i in range(num):
        #bootstrap indices of first flare
        bs = sk.resample(np.arange(ind1, ind2))
        bst = np.array(data['MJD-50000'][bs])
        bsi = np.array(data['I mag'][bs])
        x = bst
        #uses original (not detrended) data
        y = np.max(bsi) - bsi + offset
        mod = GaussianModel()
        pars = mod.guess(y, x=x)
        out = mod.fit(y, pars, x=x)
        bsouts.append(out)
    bsfits = pd.DataFrame(columns=['center', 'sigma', 'fwhm', 'height', 'amp'])
    bsfits['center'] = np.zeros(num)
    #adding to DataFrame
    i = 0
    for b in bsouts:
        bsfits['center'][i] = b.params['center'].value
        bsfits['fwhm'][i] = b.params['fwhm'].value
        bsfits['height'][i] = b.params['height'].value
        bsfits['amp'][i] = b.params['amplitude'].value
        bsfits['sigma'][i] = b.params['sigma'].value
        i += 1
    #returns list of model results and DataFrame with compiled best fit parameter values
    return bsouts, bsfits
Пример #32
0
def fit_curve(ps_list):
    #--input:ps_list, (x,y)
    x = np.array([r[0] for r in ps_list])
    y = np.array([r[1] for r in ps_list])

    mod = GaussianModel()

    pars = mod.guess(y, x=x)
    bestresult = mod.fit(y, pars, x=x)

    return (bestresult.best_fit,x,y,getfloat_attr(bestresult, 'chisqr'),bestresult)
def gaussian_fit(x, y, title_name):
    mod = GaussianModel()
    pars = mod.guess(y, x=x)
    out = mod.fit(y, pars, x=x)
    plt.figure()
    plt.plot(x, y)
    plt.plot(x, out.best_fit, 'r-')
    plt.title(title_name)
    print(out.fit_report(min_correl=0.25))
    print('Center at ' + str(out.best_values['center']) + ' Angstrom')
    plt.show()
def gaussian_fit(x, y, title_name):
	mod = GaussianModel()
	pars = mod.guess(y, x=x)
	out = mod.fit(y, pars, x=x)
	plt.figure()
	plt.plot(x, y)
	plt.plot(x, out.best_fit, 'r-')
	plt.title(title_name)
	print(out.fit_report(min_correl = 0.25))
	print('Center at ' + str(out.best_values['center']) + ' Angstrom')
	plt.show()
def gaussian_fit(x, y, title_name):
	mod = GaussianModel()
	pars = mod.guess(y, x=x)
	#pars = mod.make_params(amplitude = -2000, sigma = 1, center = 6562.801)
	out = mod.fit(y, pars, x=x)
	plt.figure()
	plt.plot(x, y)
	plt.plot(x, out.best_fit, 'r-')
	plt.title(title_name)
	print(out.fit_report(min_correl = 0.25))
	print('Center at ' + str(out.best_values['center']) + ' Angstrom')
	plt.show()
Пример #36
0
def fluxError(counts, wavelength, error, continuum):
	flux_vector = []
	E_W_vector = []
	cont_avg = np.mean(continuum)
	#plt.close('all')

	for i in range(100):
		#plt.errorbar(wavelength, counts, yerr=error)
		new_counts=[]
		j = 0
		for point in counts:
			new_counts.append(np.random.normal(point, error[j]))
			j = j + 1
		new_counts = np.array(new_counts)
		#So for each N in 1000 a new counts vector is generated randomly
		#Take this data against the wavelength values and fit a gaussian 
		#each time to compute the flux. Append this to a vector and then 
		#find the standard deviation to get the flux error for that emission line
		#Note this is to be encorporated in the fitLines module so that each of the emission 
		#lines is fit in turn. Next step here is to construct the model with lmfit, 
		#guess the initial parameters and then fit the gaussian and take 
		#out.best_values('amplitude') as the flux and store in flux_vector	

		#Now use the lmfit package to perform gaussian fits to the data	
		#Construct the gaussian model
		mod = GaussianModel()

	#Take an initial guess at what the model parameters are 
	#In this case the gaussian model has three parameters, 
	#Which are amplitude, center and sigma
		pars = mod.guess(new_counts, x=wavelength)

	#We know from the redshift what the center of the gaussian is, set this
	#And choose the option not to vary this parameter 
	#Leave the guessed values of the other parameters
		pars['center'].set(value = np.mean(wavelength))


	#Now perform the fit to the data using the set and guessed parameters 
	#And the inverse variance weights form the fits file 
		out  = mod.fit(new_counts, pars, x=wavelength)
		flux = out.best_values['amplitude']
		E_W = out.best_values['amplitude'] / cont_avg
		flux_vector.append(flux)
		E_W_vector.append(E_W)
		#plt.scatter(wavelength, new_counts)
		#plt.plot(wavelength, out.best_fit)
		

	print 'Hello', flux_vector
	#Now return the standard deviation of the flux_vector as the flux error 
	return {'flux_error' : np.std(flux_vector), 'E_W_error' : np.std(E_W_vector)}	
def fit_gaussian(y,x):    
    x=array(x)
    y=array(y)
    mod=GaussianModel()
    pars=mod.guess(y,x=x)
    result=mod.fit(y,pars,x=x)
    a=result.params['amplitude'].value
    b=result.params['center'].value
    c=result.params['sigma'].value
    best=result.best_fit
    chsqred=result.redchi
    chisq=result.chisqr
    fwhm=result.params['fwhm'].value
    
    return a,b,c,best,fwhm,chisq,chsqred
Пример #38
0
 def peakFit(self, x, y):
     if len(x) == 0:
         y = self.getdBmSpec()
         y = y[self.__scalePos]
         x = self.__scaledWavelength
     y = np.power(10,y/10)
     mod = GaussianModel()
     pars = mod.guess(y, x=x)
     out  = mod.fit(y, pars, x=x)
     
     print(out.fit_report(min_correl=0.25))
     center = out.best_values['center']
     fwhm = out.best_values['sigma']*2.3548
     
     return center, fwhm#, amp
Пример #39
0
def lmfit_ngauss_constrains(x,y, params, constrains):
  """
  INPUT:
  x - is the wavelength array
  y - is the normalized flux
  params - is a list/array of initial guess values for the parameters
  		   (this controls the number of gaussians to be fitted
  		   	number of gaussians: len(params)/3 - 3 parameters per Gaussian)
  contrains - the limits of the constrains for the fit of the parameters
  OUTPUT:
  mod - the lmfit model object used for the fit
  out - the lmfit fit object that contains all the results of the fit
  init- array with the initial guess model (usefull to see the initial guess when plotting)
  """

  mods = []
  prefixes = []
  for i in range(0, len(params), 3):
    pref = "g%02i_" % (i/3)
    gauss_i = GaussianModel(prefix=pref)

    if i == 0:
      pars = gauss_i.guess(y, x=x)
    else:
      pars.update(gauss_i.make_params())
    A = params[i]
    limA = constrains[i]
    l_cen = params[i+1]
    limL = constrains[i+1]
    sigma = params[i+2]
    limS = constrains[i+2]

    pars[pref+'amplitude'].set(A, min=limA[0], max=limA[1])
    pars[pref+'center'].set(l_cen, min=limL[0], max=limL[1])
    pars[pref+'sigma'].set(sigma, min=limS[0], max=limS[1])

    mods.append(gauss_i)
    prefixes.append(pref)

  mod = mods[0]

  if len(mods) > 1:
    for m in mods[1:]:
      mod += m
  init = mod.eval(pars, x=x)
  out = mod.fit(y, pars, x=x)

  return mod, out, init
Пример #40
0
def gaussian_fit(x, y, bounds=None):
    """Fit a gaussian background to `field` in `scan`

    Parameters
    ----------
    x : array
        independent variable
    y : array
        dependent variable
    bounds : iterable
        The +/- range to fit the data to

    Returns
    -------
    fit : lmfit.model.ModelFit
        The results of fitting the data to a gaussian peak

    Examples
    --------
    >>> fit = fit_gaussian(scan.scan_data)
    >>> fit.plot()
    """
    gaussian = GaussianModel()
    center = x[np.argmax(y)]
    if bounds is None:
        lower, upper = 0, len(x)
    else:
        lower = center - bounds
        upper = center + bounds
        if lower < 0:
            lower = 0
        if upper > len(x):
            upper = len(x)
    bounds = slice(lower, upper)
    y = y[bounds]
    x = x[bounds]
    gaussian_params = gaussian.guess(y, x=x, center=center)
    model = gaussian
    return model.fit(y, x=x, params=gaussian_params)
Пример #41
0
def lmfit_ngauss_constrains(x,y, params, constrains):
  #params = params[0]
  #constrains = constrains[0]
  mods = []
  prefixes = []
  for i in range(0, len(params), 3):
    pref = "g%02i_" % (i/3)
    gauss_i = GaussianModel(prefix=pref)

    if i == 0:
      pars = gauss_i.guess(y, x=x)
    else:
      pars.update(gauss_i.make_params())

    A = params[i]
    limA = constrains[i]
    l_cen = params[i+1]
    limL = constrains[i+1]
    sigma = params[i+2]
    limS = constrains[i+2]

    pars[pref+'amplitude'].set(A, min=limA[0], max=limA[1])
    pars[pref+'center'].set(l_cen, min=limL[0], max=limL[1])
    pars[pref+'sigma'].set(sigma, min=limS[0], max=limS[1])

    mods.append(gauss_i)
    prefixes.append(pref)

  mod = mods[0]

  if len(mods) > 1:
    for m in mods[1:]:
      mod += m

  init = mod.eval(pars, x=x)
  out = mod.fit(y, pars, x=x)
  return mod, out, init
	def fitLines(self, flux, wavelength, z, weights): 	

		#Convert all into numpy arrays 
		flux = np.array(flux)
		wavelength = np.array(wavelength)
		z = np.array(z)
		weights = np.array(weights)
		error = np.sqrt(1 / weights)

		#Fit a polynomial to the continuum background emission of the galaxy
		#This is the crude way to do it 
		continuum_poly = self.fitPoly(flux, wavelength)

		#Can also compute the continuum in the more advanced way
		#masking the emission lines and using a moving average


		#Define the wavelength values of the relevant emission lines
		OII3727 = 3727.092
		OII3729 = 3729.875
		H_beta = 4862.721
		OIII4959 = 4960.295
		OIII5007 = 5008.239
		H_alpha = 6564.614
		NII6585 = 6585.27
		SII6718 = 6718.29
		SII6732 = 6732.68

		#Now apply the redshift formula to find where this will be observed
		#Note that for these SDSS spectra the OII doublet is not in range
		OII3727_shifted = OII3727 * (1 + z)
		OII3729_shifted = OII3729 * (1 + z)
		H_beta_shifted = H_beta * (1 + z)
		OIII4959_shifted = OIII4959 * (1 + z)
		OIII5007_shifted = OIII5007 * (1 + z)
		H_alpha_shifted = H_alpha * (1 + z)
		NII6585_shifted = NII6585 * (1 + z)
		SII6718_shifted = SII6718 * (1 + z)
		SII6732_shifted = SII6732 * (1 + z)

		#hellofriend
		#Will choose to mask pm 15 for each of the lines
		H_beta_index = np.where(np.logical_and(wavelength>=(H_beta_shifted - 15), wavelength<=(H_beta_shifted + 15)))
		OIII_one_index = np.where(np.logical_and(wavelength>=(OIII4959_shifted - 15), wavelength<=(OIII4959_shifted + 15)))
		OIII_two_index = np.where(np.logical_and(wavelength>=(OIII5007_shifted - 15), wavelength<=(OIII5007_shifted + 15)))
		NII_one_index = np.where(np.logical_and(wavelength>=(NII6585_shifted - 15), wavelength<=(NII6585_shifted + 15)))
		H_alpha_index = np.where(np.logical_and(wavelength>=(H_alpha_shifted - 15), wavelength<=(H_alpha_shifted + 15)))
		SII_one_index = np.where(np.logical_and(wavelength>=(SII6718_shifted - 15), wavelength<=(SII6718_shifted + 15)))
		SII_two_index = np.where(np.logical_and(wavelength>=(SII6732_shifted - 15), wavelength<=(SII6732_shifted + 15)))

		#define the mask 1 values from the index values
		mask = np.zeros(len(flux))
		mask[H_beta_index] = 1
		mask[OIII_one_index] = 1
		mask[OIII_two_index] = 1
		mask[NII_one_index] = 1
		mask[H_alpha_index] = 1
		mask[SII_one_index] = 1
		mask[SII_two_index] = 1

		#Now apply these to the flux to mask 
		masked_flux = ma.masked_array(flux, mask=mask)

		#Make my own with np.mean()
		continuum = np.empty(len(masked_flux))
		for i in range(len(masked_flux)):

			if (i + 5) < len(masked_flux):
				continuum[i] = ma.mean(masked_flux[i:i+5])
				if np.isnan(continuum[i]):
					continuum[i] = continuum[i - 1]
			else:
				continuum[i] = ma.mean(masked_flux[i-5:i])
				if np.isnan(continuum[i]):
					continuum[i] = continuum[i - 1]

		

		#Subtract the continuum from the flux, just use polynomial fit right now 
		counts = flux - continuum_poly

		#Construct a dictionary housing these shifted emission line values 
		#Note that values for the OII doublet are not present
		line_dict = {'H_beta' : H_beta_shifted, 'OIII4959' : OIII4959_shifted, 
		'OIII5007' : OIII5007_shifted, 'H_alpha' : H_alpha_shifted, 'NII6585' : NII6585_shifted, 
		'SII6718' : SII6718_shifted, 'SII6732' : SII6732_shifted}

		#Plot the initial continuum subtracted spectrum
		plt.plot(wavelength, counts)

		#Initialise a dictionary for the results in the for loop
		results_dict = {}

		#Begin for loop to fit an arbitrary number of emission lines
		for key in line_dict:
			
		
		########################################################################
		#FITTING EACH OF THE EMISSION LINES IN TURN
		########################################################################
		#We don't want to include all the data in the gaussian fit 
		#Look for the indices of the points closes to the wavelength value
		#The appropriate range is stored in fit_wavelength etc.

		#Use np.where to find the indices of data surrounding the gaussian
			new_index = np.where(np.logical_and(wavelength > (line_dict[key] - 10) ,
												wavelength < (line_dict[key] + 10)))  

		#Select only data for the fit with these indices
			fit_wavelength = wavelength[new_index]
			fit_counts = counts[new_index]
			fit_weights = weights[new_index]
			fit_continuum = continuum[new_index]
			fit_error = error[new_index]



		#Now use the lmfit package to perform gaussian fits to the data	
		#Construct the gaussian model
			mod = GaussianModel()

		#Take an initial guess at what the model parameters are 
		#In this case the gaussian model has three parameters, 
		#Which are amplitude, center and sigma
			pars = mod.guess(fit_counts, x=fit_wavelength)

		#We know from the redshift what the center of the gaussian is, set this
		#And choose the option not to vary this parameter 
		#Leave the guessed values of the other parameters
			pars['center'].set(value = line_dict[key])
			pars['center'].set(vary = 'False')

		#Now perform the fit to the data using the set and guessed parameters 
		#And the inverse variance weights form the fits file 
			out  = mod.fit(fit_counts, pars, weights = fit_weights, x=fit_wavelength)
			#print(out.fit_report(min_correl=0.25))

		#Plot the results and the spectrum to check the fit
			plt.plot(fit_wavelength, out.best_fit, 'r-')
		
		#Return the error on the flux 
			error_dict = self.fluxError(fit_counts, fit_wavelength, fit_error, continuum_poly)

		#Compute the equivalent width
			con_avg = np.mean(continuum_poly)
			E_w = out.best_values['amplitude'] / con_avg

		#The amplitude parameter is the area under the curve, equivalent to the flux
			results_dict[key] = [out.best_values['amplitude'], error_dict['flux_error'], out.best_values['sigma'], 
			2.3548200*out.best_values['sigma'], E_w, error_dict['E_W_error']]

		plt.show()	
		#plt.savefig('fitted_spectrum.png')
		#The return dictionary for this method is a sequence of results vectors
		return results_dict	
def lmfit_mngauss(x,y, *params):
    """
    Fit multiple gaussians from two spectra that are multiplied together

    INPUT:
    x - is the wavelength array
    y - is the normalized flux
    params - is a tuple of 2 list/arrays of initial guess values for the each spectras parameters
             (this controls the number of gaussians to be fitted
                 number of gaussians: len(params)/3 - 3 parameters per Gaussian)
    OUTPUT:
    mod - the lmfit model object used for the fit
    out - the lmfit fit object that contains all the results of the fit
    init- array with the initial guess model (usefull to see the initial guess when plotting)
    """
    
    m_params = params[0]
    
    m_mods = []
    prefixes = []
    for i in range(0, len(m_params), 3):
        pref = "gm%02i_" % (i/3)
        gauss_i = GaussianModel(prefix=pref)

        if i == 0:
            pars = gauss_i.guess(y, x=x)
        else:
            pars.update(gauss_i.make_params())
    
        A = m_params[i]
        l_cen = m_params[i+1]
        sigma = m_params[i+2]

        pars[pref+'amplitude'].set(A)
        pars[pref+'center'].set(l_cen)
        pars[pref+'sigma'].set(sigma)

        m_mods.append(gauss_i)
        prefixes.append(pref)
    
    m_mod = m_mods[0]
    if len(m_mods) > 1:
      for m in m_mods[1:]:
            m_mod += m

    m_one = ConstantModel(prefix="m_one_")
    prefixes.append("m_one_")
    pars.update(m_one.make_params())
    pars['m_one_c'].set(value=1, vary=False)

    try: 
        n_params = params[1]
        n_mods = []
        #prefixes = []
        for j in range(0, len(n_params), 3):
            pref = "gn%02i_" % (j/3)
            gauss_j = GaussianModel(prefix=pref)
            pars.update(gauss_j.make_params())
        
            A = n_params[j]
            l_cen = n_params[j+1]
            sigma = n_params[j+2]

            pars[pref+'amplitude'].set(A)
            pars[pref+'center'].set(l_cen)
            pars[pref+'sigma'].set(sigma)

            n_mods.append(gauss_j)
            prefixes.append(pref)
        
        n_mod = n_mods[0]
        if len(n_mods) > 1:
            for n in n_mods[1:]:
                n_mod += n
        
        n_one = ConstantModel(prefix="n_one_")
        prefixes.append("n_one_")
        pars.update(n_one.make_params())
        pars['n_one_c'].set(value=1, vary=False)

        mod = (m_one + m_mod) * (n_one + n_mod)
    except:
    	print("Error with second spectra, only fitting first")
        mod = m_one + m_mod
    
    

    init = mod.eval(pars, x=x)
    out = mod.fit(y, pars, x=x)
    
    print("Printed prefixes", prefixes)
    #print(init)
    return mod, out, init
exp_mod = ExponentialModel(prefix='exp_')
gauss1  = GaussianModel(prefix='g1_')
gauss2  = GaussianModel(prefix='g2_')

def index_of(arrval, value):
    "return index of array *at or below* value "
    if value < min(arrval):  return 0
    return max(np.where(arrval<=value)[0])

ix1 = index_of(x,  75)
ix2 = index_of(x, 135)
ix3 = index_of(x, 175)

pars1 = exp_mod.guess(y[:ix1], x=x[:ix1])
pars2 = gauss1.guess(y[ix1:ix2], x=x[ix1:ix2])
pars3 = gauss2.guess(y[ix2:ix3], x=x[ix2:ix3])

pars = pars1 + pars2 + pars3
mod = gauss1 + gauss2 + exp_mod

out = mod.fit(y, pars, x=x)

print(out.fit_report(min_correl=0.5))

plt.plot(x, y)
plt.plot(x, out.init_fit, 'k--')
plt.plot(x, out.best_fit, 'r-')
plt.show()
#<end examples/doc_nistgauss2.py>
Пример #45
0
#Module Preparing
import numpy as np
import matplotlib.pyplot as plt
'''
也可以使用import pylab as pl
'''

from lmfit.models import GaussianModel

#Read data from file
data=np.loadtxt('**实验数据文件**')
x=data[:,0]
y=data[:,1]

#Preparing the Model
model=GaussianModel()
pars=model.guess(y,x=x)

#Do the fit
result=model.fit(y,pars,x=x)

#Print the fit result
print(result.fit_report(min_correl=0.25))

#Draw the plot
pl.plot(x,y,color='red',linestyle='--')

pl.plot(x,result.best_fit,color='blue',linestyle='-')

#Tobe Continue
Пример #46
0
def measure_line_index(wave,
                       flux,
                       flux_err=None,
                       mask=None,
                       z=None,
                       line_info=None,
                       num_refit=(100, None),
                       filepath=None,
                       return_type='dict',
                       verbose=False):
    """ Measure line index / EW and have it plotted

    Parameters
    ----------
    wave: array-like
        wavelength vector

    flux: array-like
        flux vector

    flux_err: array-like
        flux error vector (optional)
        If un-specified, auto-generate an np.ones array

    mask: array-like
        andmask or ormask (optional)
        If un-specified, auto-generate an np.ones array (evenly weighted)

    line_info: dict
        information about spectral line, eg:
        line_info_dib5780 = {'line_center':         5780,
                             'line_range':          (5775, 5785),
                             'line_shoulder_left':  (5755, 5775),
                             'line_shoulder_right': (5805, 5825)}

    num_refit: non-negative integer
        number of refitting.
        If 0, no refit will be performed
        If positive, refits will be performed after adding normal random noise

    z: float
        redshift (only specify when z is large)

    filepath: string
        path of the diagnostic figure
        if None, do nothing, else print diagnostic figure

    return_type: string
        'dict' or 'array'
        if 'array', np.array(return dict.values())

    verbose: bool
        if True, print details

    Returns
    -------
    line_indx: dict
        A dictionary type result of line index.
        If any problem encountered, return the default result (filled with nan).

    """
    try:
        # 0. do some input check
        # 0.1> check line_info
        line_info_keys = line_info.keys()
        assert 'line_range' in line_info_keys
        assert 'line_shoulder_left' in line_info_keys
        assert 'line_shoulder_right' in line_info_keys
        # 0.2> check line range/shoulder in spectral range
        assert np.min(wave) <= line_info['line_shoulder_left'][0]
        assert np.max(wave) >= line_info['line_shoulder_right'][0]

        # 1. get line information
        # line_center = line_info['line_center']  # not used
        line_range = line_info['line_range']
        line_shoulder_left = line_info['line_shoulder_left']
        line_shoulder_right = line_info['line_shoulder_right']

        # 2. shift spectra to rest-frame
        wave = np.array(wave)
        flux = np.array(flux)
        if z is not None:
            wave /= 1. + z

        # 3. estimate the local continuum
        # 3.1> shoulder wavelength range
        ind_shoulder = np.any([
            np.all([wave > line_shoulder_left[0],
                    wave < line_shoulder_left[1]], axis=0),
            np.all([wave > line_shoulder_right[0],
                    wave < line_shoulder_right[1]], axis=0)], axis=0)
        wave_shoulder = wave[ind_shoulder]
        flux_shoulder = flux[ind_shoulder]

        # 3.2> integrated/fitted wavelength range
        ind_range = np.logical_and(wave > line_range[0], wave < line_range[1])
        wave_range = wave[ind_range]
        flux_range = flux[ind_range]
        # flux_err_range = flux_err[ind_range]  # not used
        mask_range = mask[ind_range]
        flux_err_shoulder = flux_err[ind_shoulder]
        # mask_shoulder = mask[ind_shoulder]    # not used

        # 4. linear model
        mod_linear = LinearModel(prefix='mod_linear_')
        par_linear = mod_linear.guess(flux_shoulder, x=wave_shoulder)
        # ############################################# #
        # to see the parameter names:                   #
        # model_linear.param_names                      #
        # {'linear_fun_intercept', 'linear_fun_slope'}  #
        # ############################################# #
        out_linear = mod_linear.fit(flux_shoulder,
                                    par_linear,
                                    x=wave_shoulder,
                                    method='leastsq')

        # 5. estimate continuum
        cont_shoulder = out_linear.best_fit
        noise_std = np.std(flux_shoulder / cont_shoulder)
        cont_range = mod_linear.eval(out_linear.params, x=wave_range)
        resi_range = 1 - flux_range / cont_range

        # 6.1 Integrated EW (
        # estimate EW_int
        wave_diff = np.diff(wave_range)
        wave_step = np.mean(np.vstack([np.hstack([wave_diff[0], wave_diff]),
                                       np.hstack([wave_diff, wave_diff[-1]])]),
                            axis=0)
        EW_int = np.dot(resi_range, wave_step)

        # estimate EW_int_err
        num_refit_ = num_refit[0]
        if num_refit_ is not None and num_refit_>0:
            EW_int_err = np.std(np.dot(
                (resi_range.reshape(1, -1).repeat(num_refit_, axis=0) +
                 np.random.randn(num_refit_, resi_range.size) * noise_std),
                wave_step))

        # 6.2 Gaussian model
        # estimate EW_fit
        mod_gauss = GaussianModel(prefix='mod_gauss_')
        par_gauss = mod_gauss.guess(resi_range, x=wave_range)
        out_gauss = mod_gauss.fit(resi_range, par_gauss, x=wave_range)
        line_indx = collections.OrderedDict([
            ('SN_local_flux_err',        np.median(flux_shoulder / flux_err_shoulder)),
            ('SN_local_flux_std',        1. / noise_std),
            ('num_bad_pixel',            np.sum(mask_range != 0)),
            ('EW_int',                   EW_int),
            ('EW_int_err',               EW_int_err),
            ('mod_linear_slope',         out_linear.params[mod_linear.prefix + 'slope'].value),
            ('mod_linear_slope_err',     out_linear.params[mod_linear.prefix + 'slope'].stderr),
            ('mod_linear_intercept',     out_linear.params[mod_linear.prefix + 'intercept'].value),
            ('mod_linear_intercept_err', out_linear.params[mod_linear.prefix + 'intercept'].stderr),
            ('mod_gauss_amplitude',      out_gauss.params[mod_gauss.prefix + 'amplitude'].value),
            ('mod_gauss_amplitude_err',  out_gauss.params[mod_gauss.prefix + 'amplitude'].stderr),
            ('mod_gauss_center',         out_gauss.params[mod_gauss.prefix + 'center'].value),
            ('mod_gauss_center_err',     out_gauss.params[mod_gauss.prefix + 'center'].stderr),
            ('mod_gauss_sigma',          out_gauss.params[mod_gauss.prefix + 'sigma'].value),
            ('mod_gauss_sigma_err',      out_gauss.params[mod_gauss.prefix + 'sigma'].stderr),
            ('mod_gauss_amplitude_std',  np.nan),
            ('mod_gauss_center_std',     np.nan),
            ('mod_gauss_sigma_std',      np.nan)])

        # estimate EW_fit_err
        num_refit_ = num_refit[1]
        if num_refit_ is not None and num_refit_ > 2:
            # {'mod_gauss_amplitude',
            #  'mod_gauss_center',
            #  'mod_gauss_fwhm',
            #  'mod_gauss_sigma'}
            out_gauss_refit_amplitude = np.zeros(num_refit_)
            out_gauss_refit_center = np.zeros(num_refit_)
            out_gauss_refit_sigma = np.zeros(num_refit_)
            # noise_fit = np.random.randn(num_refit,resi_range.size)*noise_std
            for i in range(int(num_refit_)):
                # resi_range_with_noise = resi_range + noise_fit[i,:]
                resi_range_with_noise = resi_range + \
                                        np.random.randn(resi_range.size) * noise_std
                out_gauss_refit = mod_gauss.fit(resi_range_with_noise,
                                                par_gauss,
                                                x=wave_range)
                out_gauss_refit_amplitude[i],\
                out_gauss_refit_center[i],\
                out_gauss_refit_sigma[i] =\
                    out_gauss_refit.params[mod_gauss.prefix + 'amplitude'].value,\
                    out_gauss_refit.params[mod_gauss.prefix + 'center'].value,\
                    out_gauss_refit.params[mod_gauss.prefix + 'sigma'].value
                print(out_gauss_refit_amplitude[i], out_gauss_refit_center[i], out_gauss_refit_sigma[i])
            line_indx.update({'mod_gauss_amplitude_std': np.nanstd(out_gauss_refit_amplitude),
                              'mod_gauss_center_std':    np.nanstd(out_gauss_refit_center),
                              'mod_gauss_sigma_std':     np.nanstd(out_gauss_refit_sigma)})

        # 7. plot and save image
        if filepath is not None and os.path.exists(os.path.dirname(filepath)):
            save_image_line_indice(filepath, wave, flux, ind_range, cont_range,
                                   ind_shoulder, line_info)

        # if necessary, convert to array
        # NOTE: for a non-ordered dict the order of keys and values may change!
        if return_type == 'array':
            return np.array(line_indx.values())
        return line_indx
    except Exception:
        return measure_line_index_null_result(return_type)
Пример #47
0
    # ax_res_y2.set_yticks((ax_res.get_yticks() / 100) * yNorm)
    for xticklabel in ax.get_xticklabels():
        xticklabel.set_visible(False)
    for xticklabel in axy2.get_xticklabels():
        xticklabel.set_visible(False)
    ax.get_yticklabels()[0].set_visible(False)
    axy2.get_yticklabels()[0].set_visible(False)
    ax_res.get_yticklabels()[-1].set_visible(False)
    ax_res_y2.get_yticklabels()[-1].set_visible(False)
    if legend:
        ax.legend(loc='best')
    ax_res.set_xlabel(xlabel)
    ax.set_ylabel(ylabel)
    return fig, [ax, axy2, ax_res, ax_res_y2]

if __name__ == '__main__':
    from functions import gaussian
    from lmfit.models import GaussianModel
    x = np.linspace(-3, 3, 200)
    y = gaussian(x, sigma=0.5) * (1 + np.random.normal(0, 0.1, len(x)))
    gmod = GaussianModel()
    para = gmod.guess(y, x=x)
    gfit = gmod.fit(y, para, x=x)
    models = [gfit.init_fit, gfit.best_fit]
    plt.close('all')
    fig, axes = plotResidual(x, y, models, yNorm=1.0, yThresh=0.1)
    axes[0].set_ylabel('relative [%]')
    axes[1].set_ylabel('absolute')
    axes[2].set_xlabel('xxx')
    plt.show()
Пример #48
0
    da = s / (np.pi*fac)
    dmu = (2. * A * (xx-mu)*s)/(np.pi * fac**2)
    return np.array([ds, dmu, da])


if __name__ == '__main__':
    xs = np.linspace(-4, 4, 100)

    print('**********************************')
    print('***** Test Gaussian **************')
    print('**********************************')
    ys = gaussian(xs, 2.5, 0, 0.5)
    yn = ys + 0.1*np.random.normal(size=len(xs))

    mod = GaussianModel()
    pars = mod.guess(yn, xs)
    out = mod.fit(yn, pars, x=xs)
    out2 = mod.fit(yn, pars, x=xs, fit_kws={'Dfun': dfunc_gaussian,
                                            'col_deriv': 1})
    print('lmfit without dfunc **************')
    print('number of function calls: ', out.nfev)
    print('params', out.best_values)
    print('lmfit with dfunc *****************')
    print('number of function calls: ', out2.nfev)
    print('params', out2.best_values)
    print('\n \n')
    out2.plot(datafmt='.')

    print('**********************************')
    print('***** Test Lorentzian ************')
    print('**********************************')
Пример #49
0
cont = 3.0   # continuum level
randamp = 3. # amplitude of gaussian noise

x   = np.arange(0,xmax)
y   = randamp * np.random.randn(xmax) + jrr.spec.onegaus(x, aa, bb, cc, cont)
err = randamp * np.random.randn(xmax)
plt.plot(x, y, color='black')

# Let's try fitting that gaussian w the python version of MPFIT
p0 = (50., xmax/2, 5, 2)
fa = {'x':x, 'y':y, 'err':err}
m = mpfit.mpfit(myfunct, p0, functkw=fa)
# There has got to be a less kludgy way to do line below
bestfit = jrr.spec.onegaus(x, m.params[0], m.params[1], m.params[2], m.params[3])
plt.plot(x, bestfit, color='blue')


# The same, but with LMFIT
mod1 = GaussianModel()
mod2 = ConstantModel()  # The continuum level
mod = mod1 + mod2
pars = mod1.guess(y, x=x) + mod2.guess(y, x=x)  # This is cool.  It made rough guesses for us.
pars['c'].min = 0  # Set bounds on continuum
pars['c'].max = 10 # Set bounds on continuum
#pars['amplitude'].vary = False  # Fix a parameter
out = mod.fit(y, pars, x=x, weights=1/err**2)  # Fitting is done here.
plt.plot(x, out.best_fit, color='orange')
print(out.fit_report(min_correl=0.25))
plt.show()
# This is actually more elegant.  I think I should learn LMFIT and use it...
 def CurveFitting(self, frec, Pxx, iaf, ax):
     'Non-Linear Least-Squares Minimization and Curve-Fitting for Python'
     
     # ----- adjusting a model to the obtained PSD -----               
     # model 1: constante
     g1 = ConstantModel(prefix = 'g1_')
     pars = g1.guess(Pxx, x = frec)    
     pars['g1_c'].set(0)
     # model 2: k2/f^-1
     g2 = PowerLawModel(prefix = 'g2_')
     pars += g2.guess(Pxx, x = frec)
     pars['g2_exponent'].set(-1)
     #model 3: probability density function
     g3 = GaussianModel(prefix = 'g3_')
     pars += g3.guess(Pxx, x = frec)
     pars['g3_center'].set(iaf, min = iaf-2, max = iaf+2)
     # model 4: probability density function
     g4 = GaussianModel(prefix = 'g4_')
     pars += g4.guess(Pxx, x = frec)
     pars['g4_center'].set(20, min = 16, max = 25)
     # final model
     gA = g1 + g2 + g3 + g4
     outA = gA.fit(Pxx, pars, x = frec) 
     diffA= np.sum(Pxx - outA.best_fit)        
     gB = g1 + g2 + g3 
     outB = gB.fit(Pxx, pars, x = frec) 
     diffB= np.sum(Pxx - outB.best_fit)
     gC = g1 + g2 
     outC = gC.fit(Pxx, pars, x = frec) 
     diffC= np.sum(Pxx - outC.best_fit)
     diffs= np.abs([diffA, diffB, diffC])
     idx  = np.where(diffs == np.min(diffs))[0][0]
     out  = [outA, outB, outC][idx]
     # ----- plotting the desire PSD -----   
     # original and fitted curves
     ax.plot(frec, Pxx, 'k', linewidth = 2, label = 'PSD')
     ax.plot(frec, out.best_fit, 'b.-', linewidth = 2, markersize = 9, label ='BestModel')
     ax.set_xlim(frec[0], 32)
     ax.set_ylim(ymin = 0)
     ax.tick_params(axis = 'both', labelsize = 16)
     ax.set_xlabel('Frequency [Hz]', fontsize = 'x-large')
     ax.grid()
     # components of the fitted curved
     comps = out.eval_components(x = frec)
     g12 = comps['g1_'] + comps['g2_']
     ax.plot(frec, g12, 'g--', linewidth = 2, label = 'PowerLawModel')      
     idx1, idx2 = np.where(frec >= 5)[0][0], np.where(frec <= 15)[0][-1]
     # final value on the subplot
     if out != outC:
         diffs = out.best_fit[idx1:idx2] - g12[idx1:idx2]
         peak1 = np.amax(diffs)
         idx = np.where(diffs == peak1)[0]
         idx+= len(out.best_fit[:idx1])
         ax.plot((frec[idx],frec[idx]), (g12[idx],out.best_fit[idx]), 'r-o', linewidth = 3, markersize = 9) 
         ax.text(frec[idx], g12[idx], str(np.around(peak1, decimals=2)), horizontalalignment='right', verticalalignment='top', color='r', fontsize='xx-large')
     else:
         peak1 = 0
     # optional valued on the subplot        
     diffs = Pxx[idx1:idx2] - g12[idx1:idx2]
     peak2 = np.amax(diffs)        
     idx = np.where(peak2 == diffs)[0]
     idx+= len(Pxx[:idx1])
     ax.plot((frec[idx],frec[idx]), (g12[idx], Pxx[idx]), 'r-*', linewidth = 3, markersize = 11) 
     ax.text(frec[idx], Pxx[idx], str(np.around(peak2, decimals=2)), horizontalalignment='left', verticalalignment='top', color='r', fontsize='xx-large')
     ax.legend(loc='upper right', shadow=True)
     
     return peak1, peak2
Пример #51
0
# MODEL = 'loren'
# MODEL = 'voigt'
# gamma_free = True

if MODEL.lower().startswith('g'):
    mod = GaussianModel()
    gamma_free = False
    figname = '../doc/_images/models_peak1.png'
elif MODEL.lower().startswith('l'):
    mod = LorentzianModel()
    gamma_free = False
    figname = '../doc/_images/models_peak2.png'
elif MODEL.lower().startswith('v'):
    mod = VoigtModel()
    figname = '../doc/_images/models_peak3.png'

pars = mod.guess(y, x=x)

if gamma_free:
    pars['gamma'].set(value=0.7, vary=True, expr='')
    figname = '../doc/_images/models_peak4.png'

out = mod.fit(y, pars, x=x)
print(out.fit_report(min_correl=0.25))

plt.plot(x, y, 'b-')
plt.plot(x, out.best_fit, 'r-')
# plt.savefig(figname)
plt.show()
# <end examples/doc_builtinmodels_peakmodels.py>