mappings, including tests

GPy/testing/mapping_tests.py

@@ -0,0 +1,72 @@
+# Copyright (c) 2012, 2013 GPy authors (see AUTHORS.txt).
+# Licensed under the BSD 3-clause license (see LICENSE.txt)
+
+import unittest
+import numpy as np
+import GPy
+
+class MappingGradChecker(GPy.core.Model):
+    """
+    This class has everything we need to check the gradient of a mapping. It
+    implement a simple likelihood which is a weighted sum of the outputs of the
+    mapping. the gradients are checked against the parameters of the mapping
+    and the input.
+    """
+    def __init__(self, mapping, X, name='map_grad_check'):
+        super(MappingGradChecker, self).__init__(name)
+        self.mapping = mapping
+        self.link_parameter(self.mapping)
+        self.X = GPy.core.Param('X',X)
+        self.link_parameter(self.X)
+        self.dL_dY = np.random.randn(self.X.shape[0], self.mapping.output_dim)
+    def log_likelihood(self):
+        return np.sum(self.mapping.f(self.X) * self.dL_dY)
+    def parameters_changed(self):
+        self.X.gradient = self.mapping.gradients_X(self.dL_dY, self.X)
+        self.mapping.update_gradients(self.dL_dY, self.X)
+
+
+
+
+
+
+
+class MappingTests(unittest.TestCase):
+
+    def test_kernelmapping(self):
+        X = np.random.randn(100,3)
+        Z = np.random.randn(10,3)
+        mapping = GPy.mappings.Kernel(3, 2, Z, GPy.kern.RBF(3))
+        self.assertTrue(MappingGradChecker(mapping, X).checkgrad())
+
+    def test_linearmapping(self):
+        mapping = GPy.mappings.Linear(3, 2)
+        X = np.random.randn(100,3)
+        self.assertTrue(MappingGradChecker(mapping, X).checkgrad())
+
+    def test_mlpmapping(self):
+        mapping = GPy.mappings.MLP(input_dim=3, hidden_dim=5, output_dim=2)
+        X = np.random.randn(100,3)
+        self.assertTrue(MappingGradChecker(mapping, X).checkgrad())
+
+    def test_addmapping(self):
+        m1 = GPy.mappings.MLP(input_dim=3, hidden_dim=5, output_dim=2)
+        m2 = GPy.mappings.Linear(input_dim=3, output_dim=2)
+        mapping = GPy.mappings.Additive(m1, m2)
+        X = np.random.randn(100,3)
+        self.assertTrue(MappingGradChecker(mapping, X).checkgrad())
+
+    def test_compoundmapping(self):
+        m1 = GPy.mappings.MLP(input_dim=3, hidden_dim=5, output_dim=2)
+        Z = np.random.randn(10,2)
+        m2 = GPy.mappings.Kernel(2, 4, Z, GPy.kern.RBF(2))
+        mapping = GPy.mappings.Compound(m1, m2)
+        X = np.random.randn(100,3)
+        self.assertTrue(MappingGradChecker(mapping, X).checkgrad())
+
+
+
+
+if __name__ == "__main__":
+    print "Running unit tests, please be (very) patient..."
+    unittest.main()