def test_001_exceptions (self):
""" check it fails for invalid input """
valid_ber = (0.5,) * 3
invalid_ber1 = (0.5,) * 4 # Too long
invalid_ber2 = (0.5, 0.5, 2) # BER=2
valid_trans_matrix = (0.8, 0.15, 0.05,
0.1, 0.6, 0.3,
0.2, 0.1, 0.7)
invalid_trans_matrix1= (0.8, 0.15, 0.2, # Doesn't add up to one
0.1, 0.6, 0.3,
0.2, 0.1, 0.7)
invalid_trans_matrix2= (0.8, 0.15, 0.05,
0.1, 0.6, 0.3) # Wrong size
self.assertRaises(ValueError,
lambda: cc.markovchan_bb(invalid_ber1, valid_trans_matrix))
self.assertRaises(ValueError,
lambda: cc.markovchan_bb(invalid_ber2, valid_trans_matrix))
self.assertRaises(ValueError,
lambda: cc.markovchan_bb(invalid_ber1, invalid_trans_matrix1))
self.assertRaises(ValueError,
lambda: cc.markovchan_bb(valid_ber, invalid_trans_matrix1))
self.assertRaises(ValueError,
lambda: cc.markovchan_bb(valid_ber, invalid_trans_matrix2))
self.assertRaises(ValueError,
lambda: cc.markovchan_bb(valid_ber, valid_trans_matrix, 9))
self.assertRaises(ValueError,
lambda: cc.markovchan_bb(valid_ber, valid_trans_matrix, 8, 5))
try:
m = cc.markovchan_bb(valid_ber, valid_trans_matrix)
m = cc.markovchan_bb(valid_ber, valid_trans_matrix, 8, 0)
except ValueError:
self.fail("An error was raised, but shouldn't have.")
def test_003_t (self):
""" two states, random switching """
n_bytes = 10000
ber = (0, 0.5)
trans_matrix = (0.5, 0.5,
0.5, 0.5)
src = gr.glfsr_source_b(32) # Create some pseudo-random bits
head = gr.head(1, n_bytes)
chan = cc.markovchan_bb(ber, trans_matrix, 8)
ber = cc.ber_b(8)
sink_state = gr.vector_sink_i()
self.tb.connect(src, head, chan, (ber, 0))
self.tb.connect(head, (ber, 1))
self.tb.connect((chan, 1), sink_state)
self.tb.run ()
n_times_in_state_1 = np.sum(sink_state.data())
print "\nNumber of times in state 1 = " + str(n_times_in_state_1)
print " Expected value = " + str(n_bytes/2)
self.assertTrue(n_times_in_state_1 > 3500 and n_times_in_state_1 < 6500,
"Due to the statistical nature of the bsc, this can actually fail (though very unlikely). Try again.")
print " Measured BER = " + str(ber.ber())
print "Expected value = 0.25"
self.assertTrue(abs(ber.ber()- 0.25) < 0.05,
msg="Due to the statistical nature of the bsc, this can actually fail (though very unlikely). Try again.")
def test_002_t (self):
""" two state: one errorless, and the other can never be reached """
n_bytes = 10000
ber = (0, 0.5)
trans_matrix = (1.0, 0.0,
1.0, 0.0)
src = gr.glfsr_source_b(32) # Create some pseudo-random bits
head = gr.head(1, n_bytes)
chan = cc.markovchan_bb(ber, trans_matrix, 8)
ber = cc.ber_b(8)
sink_state = gr.vector_sink_i()
self.tb.connect(src, head, chan, (ber, 0))
self.tb.connect(head, (ber, 1))
self.tb.connect((chan, 1), sink_state)
self.tb.run ()
self.assertEqual(ber.ber(), 0)
self.assertEqual(sink_state.data(), (0,) * n_bytes, "State was not always 0!")