python unit test for FitBasis

python/gtsam/tests/test_basis.py

@@ -0,0 +1,38 @@
+"""
+GTSAM Copyright 2010-2019, Georgia Tech Research Corporation,
+Atlanta, Georgia 30332-0415
+All Rights Reserved
+
+See LICENSE for the license information
+
+Basis unit tests.
+Author: Frank Dellaert & Gerry Chen (Python)
+"""
+import unittest
+
+import numpy as np
+
+import gtsam
+from gtsam.utils.test_case import GtsamTestCase
+from gtsam.symbol_shorthand import B
+
+class TestBasis(GtsamTestCase):
+    def test_fit_basis(self):
+        f = lambda x: x  # line y = x
+        N = 2
+        datax = [0., 0.5, 0.75]
+        interpx = np.linspace(0., 1., 10)
+        noise = gtsam.noiseModel.Unit.Create(1)
+        def testBasis(fitter, basis, f=f):
+            data = {x: f(x) for x in datax}
+            fit = fitter(N, data, noise)
+            coeff = fit.parameters()
+            interpy = basis.WeightMatrix(N, interpx) @ coeff
+            np.testing.assert_almost_equal(interpy, np.array([f(x) for x in interpx]), decimal=7)
+        testBasis(gtsam.FitBasisFourierBasis, gtsam.FourierBasis, f=lambda x: 0.7*np.cos(x))
+        testBasis(gtsam.FitBasisChebyshev1Basis, gtsam.Chebyshev1Basis)
+        testBasis(gtsam.FitBasisChebyshev2Basis, gtsam.Chebyshev2Basis)
+        testBasis(gtsam.FitBasisChebyshev2, gtsam.Chebyshev2)
+
+if __name__ == "__main__":
+    unittest.main()