add function integration, tests and docs

tests/test_fit.py

@@ -1,15 +1,53 @@
+"""Test of fit module.
+
+:Date: 2019-05-29
+
+.. module:: test_fit
+  :platform: *nix, Windows
+  :synopsis: Test of fit module.
+
+.. moduleauthor:: Daniel Weschke <daniel.weschke@directbox.de>
+"""
 import unittest
 
 import os
 import sys
+from pylab import array, argmax, subplot, plot, title, xlim, show, gradient, linspace
 sys.path.insert(0, os.path.abspath('../src'))
-import fit
+from data import data_read
+from numerical.fit import gauss_fit
 
 
 class TestFit(unittest.TestCase):
 
-  def test_property(self):
-    self.assertEqual()
+  def test_gauss(self):
+    """test function"""
+    file_name = "test_fit.dat"
+    x, y = data_read(file_name, 3, 2)
+    
+    subplot(2,2,1)
+    plot(x, y, '.-')
+    
+    subplot(2,2,2)
+    dx = x[1] - x[0]
+    dydx = gradient(y, dx)  # central differences
+    x_fit = linspace(x[0], x[-1], 150 if len(x) < 50 else len(x)*3)
+    y_fit, popt, FWHM = gauss_fit(list(reversed(x)), list(reversed(dydx)), x_fit=x_fit, verbose=True)   # x must increase!
+    plot(x, dydx, '.-')
+    plot(x_fit, y_fit, 'r:')
+    title('FWHM: %f' % FWHM)
+    
+    subplot(2,2,3)
+    plot(x, y, '.-')
+    xlim(popt[1]-2*FWHM, popt[1]+2*FWHM)
+    
+    subplot(2,2,4)
+    plot(x, dydx, '.-')
+    plot(x_fit, y_fit, 'r:')
+    xlim(popt[1]-2*FWHM, popt[1]+2*FWHM)
+    
+    show()
+    self.assertEqual(FWHM, 0.12975107355013618)
 
 
 if __name__ == '__main__':