def test_rnn_step_backward(self):
print('Checking RNN Step backward')
np.random.seed(231)
N, D, H = 4, 5, 6
x = np.random.randn(N, D)
h = np.random.randn(N, H)
Wx = np.random.randn(D, H)
Wh = np.random.randn(H, H)
b = np.random.randn(H)
out, cache = rnn_step_forward(x, h, Wx, Wh, b)
dnext_h = np.random.randn(*out.shape)
def fx(x):
return rnn_step_forward(x, h, Wx, Wh, b)[0]
def fh(prev_h):
return rnn_step_forward(x, h, Wx, Wh, b)[0]
def fWx(Wx):
return rnn_step_forward(x, h, Wx, Wh, b)[0]
def fWh(Wh):
return rnn_step_forward(x, h, Wx, Wh, b)[0]
def fb(b):
return rnn_step_forward(x, h, Wx, Wh, b)[0]
dx_num = self.eval_numerical_gradient_array(fx, x, dnext_h)
dprev_h_num = self.eval_numerical_gradient_array(fh, h, dnext_h)
dWx_num = self.eval_numerical_gradient_array(fWx, Wx, dnext_h)
dWh_num = self.eval_numerical_gradient_array(fWh, Wh, dnext_h)
db_num = self.eval_numerical_gradient_array(fb, b, dnext_h)
dx, dprev_h, dWx, dWh, db = rnn_step_backward(dnext_h, cache)
self.assertTrue(
self.rel_error(dx_num, dx) < 1e-5,
"dx elative error should be less than 1e-5")
self.assertTrue(
self.rel_error(dprev_h_num, dprev_h) < 1e-5,
"dprev_h relative error should be less than 1e-5")
self.assertTrue(
self.rel_error(dWx_num, dWx) < 1e-5,
"dWx relative error should be less than 1e-5")
self.assertTrue(
self.rel_error(dWh_num, dWh) < 1e-5,
"dWh relative error should be less than 1e-5")
self.assertTrue(
self.rel_error(db_num, db) < 1e-5,
"db relative error should be less than 1e-5")
def test_rnn_step_forward(self):
N, D, H = 3, 10, 4
print('Checking RNN Step forward')
x = np.linspace(-0.4, 0.7, num=N * D).reshape(N, D)
prev_h = np.linspace(-0.2, 0.5, num=N * H).reshape(N, H)
Wx = np.linspace(-0.1, 0.9, num=D * H).reshape(D, H)
Wh = np.linspace(-0.3, 0.7, num=H * H).reshape(H, H)
b = np.linspace(-0.2, 0.4, num=H)
next_h, _ = rnn_step_forward(x, prev_h, Wx, Wh, b)
expected_next_h = np.asarray(
[[-0.58172089, -0.50182032, -0.41232771, -0.31410098],
[0.66854692, 0.79562378, 0.87755553, 0.92795967],
[0.97934501, 0.99144213, 0.99646691, 0.99854353]])
self.assertTrue(
self.rel_error(expected_next_h, next_h) < 1e-5,
"Relative error should be less than 1e-5")
def fb(b):
return rnn_step_forward(x, h, Wx, Wh, b)[0]
def fWh(Wh):
return rnn_step_forward(x, h, Wx, Wh, b)[0]
def fWx(Wx):
return rnn_step_forward(x, h, Wx, Wh, b)[0]
def fh(prev_h):
return rnn_step_forward(x, h, Wx, Wh, b)[0]