def guess_parameters(self):
fit = Fit(self.data, self.functions)
y = np.array(fit.y)
for f in self.functions:
guess = f.module.guess(fit.x, y)
map(lambda p, g: p.__setattr__('value', g), f.parameters, guess)
y = y - f.module.values(fit.x, guess)
def mfit(data, xmin, xmax, ymin, ymax, dy):
fs = [Function('Linear', linear), Function('Gaussian', gaussian)]
x = np.linspace(xmin, xmax, 200)
ylo, yhi = ymin, ymin + dy
while yhi < ymax:
slab = data[ylo:yhi, xmin:xmax]
diff = slab.nxsignal.shape[0]
cut = slab.sum([0])
cut.plot()
fit = Fit(cut, fs, use_errors=True)
y = np.array(fit.y)
for f in fs:
f.guess_parameters(fit.x, y)
y = y - f.function_values(fit.x)
fit.fit_data()
NXdata(fit.get_model(x), x).oplot('-')
if raw_input('Keep? [y,N] ') == 'y':
data[ylo:yhi, xmin:xmax] = slab - fit.get_model(f=fs[1]) / diff
ylo = yhi
yhi = ylo + dy
return data
def get_model(self, f=None):
self.read_parameters()
fit = Fit(self.data, self.functions)
if self.plot_checkbox.isChecked():
x = fit.x
else:
x = np.linspace(float(self.plot_minbox.text()),
float(self.plot_maxbox.text()), 1001)
return NXdata(NXfield(fit.get_model(x, f), name='model'),
NXfield(x, name=fit.data.nxaxes[0].nxname),
title='Fit Results')
def fit_data(self):
self.read_parameters()
if self.fit_checkbox.isChecked():
use_errors = True
else:
use_errors = False
from nexpy.gui.mainwindow import report_error
try:
self.fit = Fit(self.data, self.functions, use_errors)
self.fit.fit_data()
except Exception as error:
report_error("Fitting Data", error)
if self.fit.result.success:
self.fit_label.setText('Fit Successful Chi^2 = %s' %
self.fit.result.redchi)
else:
self.fit_label.setText('Fit Failed Chi^2 = %s' %
self.fit.result.redchi)
self.write_parameters()
if not self.fitted:
self.action_layout.addWidget(self.report_button)
self.action_layout.addWidget(self.restore_button)
self.save_button.setText('Save Fit')
self.fitted = True
