a first test file

theano/sandbox/scan_module/tests/test_scan.py

+import os
+import shutil
+from tempfile import mkdtemp
+import time
+import unittest
+
+import cPickle
+import numpy
+from numpy.testing import dec
+
+import theano
+import theano.sandbox.rng_mrg
+from theano import tensor
+from theano.compile.pfunc import rebuild_collect_shared
+from theano.gof.python25 import any
+from theano.tests  import unittest_tools as utt
+from numpy.testing.noseclasses import KnownFailureTest
+
+from test_utils import *
+import theano.sandbox.scan_module as scan_module
+
+
+class TestScan(unittest.TestCase):
+
+    def setUp(self):
+        utt.seed_rng()
+
+    # generator network, only one output , type scalar ; no sequence or
+    # non sequence arguments
+    def test001_generator_one_scalar_output(self):
+        def f_pow2(x_tm1):
+            return 2 * x_tm1
+        state = theano.tensor.scalar('state')
+        n_steps = theano.tensor.iscalar('nsteps')
+        output, updates = scan_module.scan(f_pow2,
+                                           [],
+                                           state,
+                                           [],
+                                           n_steps=n_steps,
+                                           truncate_gradient=-1,
+                                           go_backwards=False)
+
+        my_f = theano.function([state, n_steps],
+                               output,
+                               updates=updates,
+                               allow_input_downcast=True)
+
+        rng = numpy.random.RandomState(utt.fetch_seed())
+        state = rng.uniform()
+        steps = 5
+
+        numpy_values = numpy.array([state * (2 ** (k + 1)) for k
+                                    in xrange(steps)])
+        theano_values = my_f(state, steps)
+        assert numpy.allclose(numpy_values, theano_values)