Added ToroidalFourierDistribution

Author: FlorianPfaff

pyrecest/tests/distributions/test_toroidal_fourier_distribution.py

@@ -0,0 +1,81 @@
+import unittest
+import numpy as np
+from pyrecest.distributions.hypertorus.toroidal_fourier_distribution import ToroidalFourierDistribution
+from pyrecest.distributions.hypertorus.toroidal_von_mises_sine_distribution import ToroidalVonMisesSineDistribution
+from pyrecest.distributions.hypertorus.hypertoroidal_fourier_distribution import HypertoroidalFourierDistribution
+
+
+class ToroidalFourierDistributionTest(unittest.TestCase):
+    def setUp(self):
+        self.tvm = ToroidalVonMisesSineDistribution(np.array([1, 4]), np.array([0.3, 0.7]), 0.5)
+        self.tfd = ToroidalFourierDistribution.from_distribution(self.tvm, [15, 15], 'sqrt')
+        self.hfd = HypertoroidalFourierDistribution.from_distribution(self.tvm, [15, 15], 'sqrt')
+        self.test_points = np.random.rand(100, 2) * 4 * np.pi - np.pi
+
+    def test_single_element_vector(self):
+        ToroidalFourierDistribution([1])
+
+    def test_from_function(self):
+        tvm = ToroidalVonMisesSineDistribution(np.array([1, 2]), np.array([0.3, 0.5]), 0.5)
+        tfd1_fun = ToroidalFourierDistribution.from_function(
+            lambda x, y: np.reshape(tvm.pdf(np.column_stack([x.ravel(), y.ravel()])), x.shape),
+            [15, 15],
+            desired_transformation='identity'
+        )
+        tfd2_fun = ToroidalFourierDistribution.from_function(
+            lambda x, y: np.reshape(tvm.pdf(np.column_stack([x.ravel(), y.ravel()])), x.shape),
+            [15, 15],
+            desired_transformation='sqrt'
+        )
+        for i in range(-2, 4):
+            tvm_moment = tvm.trigonometric_moment(i)
+            np.testing.assert_allclose(tfd1_fun.trigonometric_moment(i), tvm_moment, atol=1e-6)
+            np.testing.assert_allclose(tfd1_fun.trigonometric_moment_numerical(i), tvm_moment, atol=1e-6)
+            np.testing.assert_allclose(tfd2_fun.trigonometric_moment(i), tvm_moment, atol=1e-6)
+            np.testing.assert_allclose(tfd2_fun.trigonometric_moment_numerical(i), tvm_moment, atol=1e-6)
+
+    def test_from_function_and_moments(self):
+        tvm = ToroidalVonMisesSineDistribution([1, 2], [0.3, 0.5], 0.5)
+        tfd1 = ToroidalFourierDistribution.from_distribution(tvm, [15, 15], 'identity')
+        tfd2 = ToroidalFourierDistribution.from_distribution(tvm, [15, 15], 'sqrt')
+        for i in range(-2, 4):
+            tvm_moment = tvm.trigonometric_moment(i)
+            np.testing.assert_allclose(tfd1.trigonometric_moment(i), tvm_moment, atol=1e-6)
+            np.testing.assert_allclose(tfd1.trigonometric_moment_numerical(i), tvm_moment, atol=1e-6)
+            np.testing.assert_allclose(tfd2.trigonometric_moment(i), tvm_moment, atol=1e-6)
+            np.testing.assert_allclose(tfd2.trigonometric_moment_numerical(i), tvm_moment, atol=1e-6)
+
+        with np.testing.assert_warns(Warning):
+            np.testing.assert_allclose(tfd1.trigonometric_moment(16), [0, 0])
+            np.testing.assert_allclose(tfd2.trigonometric_moment(30), [0, 0])
+
+    def test_integrate(self):
+        tvm = ToroidalVonMisesSineDistribution([1, 2], [0.6, 1], 0.2)
+        tfd_id = ToroidalFourierDistribution.from_distribution(tvm, [45, 49], 'identity')
+        tfd_sqrt = ToroidalFourierDistribution.from_distribution(tvm, [45, 49], 'sqrt')
+        l = [0.3, 0.3]
+        r = [1.5, 1.5]
+        np.testing.assert_allclose(tfd_id.integrate(l, r), tvm.integrate(l, r), atol=1e-6)
+        np.testing.assert_allclose(tfd_id.integral_numerical(l, r), tvm.integrate(l, r), atol=1e-6)
+        np.testing.assert_allclose(tfd_sqrt.integrate(l, r), tvm.integrate(l, r), atol=1e-6)
+        np.testing.assert_allclose(tfd_sqrt.integral_numerical(l, r), tvm.integrate(l, r), atol=1e-6)
+
+        tfd_simple = ToroidalFourierDistribution(np.diag([0, 1 / (4 * np.pi ** 2), 0]), 'identity')
+        np.testing.assert_allclose(tfd_simple.integrate(), 1, atol=1e-6)
+
+    def test_to_twn(self):
+        mu = [1, 3]
+        C = [[9, 0.3], [0.3, 2]]
+        twn = HypertoroidalWrappedNormalDistribution(mu, C)
+        tfd = ToroidalFourierDistribution.from_distribution(twn, 9, 'identity')
+        twn_conv = tfd.to_twn()
+        np.testing.assert_allclose(twn_conv.mu, twn.mu, atol=1e-4)
+        np.testing.assert_allclose(twn_conv.C, twn.C, atol=1e-4)
+        tfd = ToroidalFourierDistribution.from_distribution(twn, 9, 'sqrt')
+        twn_conv = tfd.to_twn()
+        np.testing.assert_allclose(twn_conv.mu, twn.mu, atol=1e-4)
+        np.testing.assert_allclose(twn_conv.C, twn.C, atol=1e-4)
+
+
+if __name__ == '__main__':
+    unittest.main()