def testComputation(self):
batch_size = 2
hidden_size = 4
inputs = tf.placeholder(tf.float32, shape=[batch_size, hidden_size])
prev_cell = tf.placeholder(tf.float32, shape=[batch_size, hidden_size])
prev_hidden = tf.placeholder(tf.float32, shape=[batch_size, hidden_size])
lstm = snt.LSTM(hidden_size)
_, next_state = lstm(inputs, (prev_hidden, prev_cell))
next_hidden, next_cell = next_state
lstm_variables = lstm.get_variables()
param_map = {param.name.split("/")[-1].split(":")[0]:
param for param in lstm_variables}
# With random data, check the TF calculation matches the Numpy version.
input_data = np.random.randn(batch_size, hidden_size)
prev_hidden_data = np.random.randn(batch_size, hidden_size)
prev_cell_data = np.random.randn(batch_size, hidden_size)
with self.test_session() as session:
tf.global_variables_initializer().run()
fetches = [(next_hidden, next_cell),
param_map[snt.LSTM.W_GATES],
param_map[snt.LSTM.B_GATES]]
output = session.run(fetches,
{inputs: input_data,
prev_cell: prev_cell_data,
prev_hidden: prev_hidden_data})
next_state_ex, gate_weights_ex, gate_biases_ex = output
in_and_hid = np.concatenate((input_data, prev_hidden_data), axis=1)
real_gate = np.dot(in_and_hid, gate_weights_ex) + gate_biases_ex
# i = input_gate, j = next_input, f = forget_gate, o = output_gate
i, j, f, o = np.hsplit(real_gate, 4)
real_cell = (prev_cell_data / (1 + np.exp(-(f + lstm._forget_bias))) +
1 / (1 + np.exp(-i)) * np.tanh(j))
real_hidden = np.tanh(real_cell) * 1 / (1 + np.exp(-o))
self.assertAllClose(real_hidden, next_state_ex[0])
self.assertAllClose(real_cell, next_state_ex[1])
评论列表
文章目录