add parabola

examples/test.py

@@ -0,0 +1,60 @@
+import sys
+import os.path as path
+
+build_dir = path.join(path.dirname(__file__), '..', 'build')
+print('Adding build directory to sys.path:', build_dir)
+sys.path.append(build_dir)
+
+import slopefit as sf
+import numpy as np
+import matplotlib.pyplot as plt
+
+
+fl = 1200.0 # mm
+theta_mrad = 3.0 # mrad
+theta_rad = theta_mrad * 1e-3
+theta = theta_rad / np.pi * 180.0 # deg
+
+parab = sf.ParabolaParams(fl, theta)
+
+filename = 'microMAX_vsru_mispu_absum.dat'
+dirname = path.dirname(__file__)
+
+data = sf.import_dat_file(path.join(dirname, filename))
+
+# flip both x and y
+data[:, 0] = -data[:, 0]
+data[:, 1] = -data[:, 1]
+
+n_skip = 20
+data = data[n_skip:-n_skip, :]
+
+ref = parab(data[:, 0])
+
+# convert ref from slope to rad
+# ref = np.arctan(ref)
+# convert to arcsec
+# ref = ref / np.pi * 180.0 * 3600.0
+
+
+plt.plot(data[:, 0], data[:, 1], 'x')
+plt.plot(data[:, 0], ref, '-')
+plt.xlabel('x (mm)')
+plt.ylabel('slope (arcsec)')
+plt.show()
+
+d_parab = sf.ParabolaParams(100.0, 0.00001)
+
+fitted = sf.fit_parabola(data, parab, d_parab)
+
+print('Fitted parameters:')
+print('fl =', fitted.focal_length)
+print('theta =', fitted.theta * np.pi * 1e3 / 180.0, 'mrad')
+
+fitted_ref = fitted(data[:, 0])
+
+plt.plot(data[:, 0], data[:, 1], 'x')
+plt.plot(data[:, 0], fitted_ref, '-')
+plt.xlabel('x (mm)')
+plt.ylabel('slope (arcsec)')
+plt.show()