basic tests for jacobian/hessian functions

theano/tensor/tests/test_2nd_order_grads.py

+"""
+WRITE ME
+
+Test for jacobian/hessian functions in Theano
+"""
+import unittest
+from theano.tests  import unittest_tools as utt
+from theano import function
+import theano
+from theano import tensor
+import numpy
+
+
+def test_jacobian():
+    x = tensor.vector()
+    y = x * 2
+    Jx = tensor.jacobian(y, x)
+    f = theano.function([x], Jx, allow_input_downcast=True)
+    vx = numpy.arange(10).astype(theano.config.floatX)
+    assert numpy.allclose(f(vx), numpy.eye(10) * 2)
+
+
+def test_hessian():
+    x = tensor.vector()
+    y = tensor.sum(x ** 2)
+    Hx = tensor.hessian(y, x)
+    f = theano.function([x], Hx, allow_input_downcast=True)
+    vx = numpy.arange(10).astype(theano.config.floatX)
+    assert numpy.allclose(f(vx), numpy.eye(10) * 2)