def check_stacked_lstm(seq_len,
input_size,
hidden_size,
batch_size,
init_func,
return_seq=True,
backward=False,
reset_cells=False,
num_iter=2):
Cin = ng.make_axis(input_size, name='Feature')
REC = ng.make_axis(seq_len, name='REC')
N = ng.make_axis(batch_size, name='N')
with ExecutorFactory() as ex:
np.random.seed(0)
inp_ng = ng.placeholder([Cin, REC, N])
lstm_ng_1 = LSTM(hidden_size,
init_func,
activation=Tanh(),
gate_activation=Logistic(),
reset_cells=reset_cells,
return_sequence=return_seq,
backward=backward)
lstm_ng_2 = LSTM(hidden_size + 1,
init_func,
activation=Tanh(),
gate_activation=Logistic(),
reset_cells=reset_cells,
return_sequence=return_seq,
backward=backward)
out_ng_1 = lstm_ng_1(inp_ng)
out_ng_2 = lstm_ng_2(out_ng_1)
fprop_neon_fun_2 = ex.executor(out_ng_2, inp_ng)
gates = ['i', 'f', 'o', 'g']
Wxh_neon_1_fun = copier_T(
ex.executor(list(lstm_ng_1.W_input[k] for k in gates)))
Whh_neon_1_fun = copier_T(
ex.executor(list(lstm_ng_1.W_recur[k] for k in gates)))
bh_neon_1_fun = copier(ex.executor(list(lstm_ng_1.b[k]
for k in gates)))
Wxh_neon_2_fun = copier_T(
ex.executor(list(lstm_ng_2.W_input[k] for k in gates)))
Whh_neon_2_fun = copier_T(
ex.executor(list(lstm_ng_2.W_recur[k] for k in gates)))
bh_neon_2_fun = copier(ex.executor(list(lstm_ng_2.b[k]
for k in gates)))
h_init_fun = ex.executor(lstm_ng_2.h_init)
# fprop on random inputs for multiple iterations
fprop_neon_2_list = []
input_value_list = []
for i in range(num_iter):
input_value = rng.uniform(-1, 1, inp_ng.axes)
fprop_neon_2 = fprop_neon_fun_2(input_value).copy()
# comparing outputs
if return_seq is True:
fprop_neon_2 = fprop_neon_2[:, :, 0]
input_value_list.append(input_value)
fprop_neon_2_list.append(fprop_neon_2)
if reset_cells is False:
# look at the last hidden states
h_init_neon = fprop_neon_2[:, -1].reshape(-1, 1)
h_init_ng = h_init_fun()
ng.testing.assert_allclose(h_init_neon,
h_init_ng,
rtol=rtol,
atol=atol)
# after the rnn graph has been executed, can get the W values. Get copies so
# shared values don't confuse derivatives
# concatenate weights to i, f, o, g together (in this order)
gates = ['i', 'f', 'o', 'g']
Wxh_neon_1 = np.concatenate(Wxh_neon_1_fun(), 1)
Whh_neon_1 = np.concatenate(Whh_neon_1_fun(), 1)
bh_neon_1 = np.concatenate(bh_neon_1_fun())
Wxh_neon_2 = np.concatenate(Wxh_neon_2_fun(), 1)
Whh_neon_2 = np.concatenate(Whh_neon_2_fun(), 1)
bh_neon_2 = np.concatenate(bh_neon_2_fun())
# reference numpy LSTM
lstm_ref_1 = RefLSTM()
lstm_ref_2 = RefLSTM()
WLSTM_1 = lstm_ref_1.init(input_size, hidden_size)
WLSTM_2 = lstm_ref_2.init(hidden_size, hidden_size + 1)
# make ref weights and biases the same with neon model
WLSTM_1[0, :] = bh_neon_1
WLSTM_1[1:input_size + 1, :] = Wxh_neon_1
WLSTM_1[input_size + 1:] = Whh_neon_1
WLSTM_2[0, :] = bh_neon_2
WLSTM_2[1:hidden_size + 1, :] = Wxh_neon_2
WLSTM_2[hidden_size + 1:] = Whh_neon_2
# transpose input X and do fprop
fprop_ref_2_list = []
c0_1 = h0_1 = None
c0_2 = h0_2 = None
for i in range(num_iter):
input_value = input_value_list[i]
inp_ref = input_value.copy().transpose([1, 2, 0])
(Hout_ref_1, cprev_1, hprev_1,
batch_cache) = lstm_ref_1.forward(inp_ref, WLSTM_1, c0_1, h0_1)
(Hout_ref_2, cprev_2, hprev_2,
batch_cache) = lstm_ref_2.forward(Hout_ref_1, WLSTM_2, c0_2, h0_2)
if reset_cells is False:
c0_1 = cprev_1
h0_1 = hprev_1
c0_2 = cprev_2
h0_2 = hprev_2
# the output needs transpose as well
Hout_ref_2 = Hout_ref_2.reshape(seq_len * batch_size,
hidden_size + 1).T
fprop_ref_2_list.append(Hout_ref_2)
for i in range(num_iter):
ng.testing.assert_allclose(fprop_neon_2_list[i],
fprop_ref_2_list[i],
rtol=rtol,
atol=atol)
def check_lstm(seq_len,
input_size,
hidden_size,
batch_size,
init_func,
inp_moms=[0.0, 1.0]):
# init_func is the initializer for the model params
# inp_moms is the [ mean, std dev] of the random input
input_shape = (input_size, seq_len * batch_size)
hidden_shape = (hidden_size, seq_len * batch_size)
NervanaObject.be.bsz = NervanaObject.be.batch_size = batch_size
# neon LSTM
lstm = LSTM(hidden_size,
init_func,
activation=Tanh(),
gate_activation=Logistic())
inp = np.random.rand(*input_shape) * inp_moms[1] + inp_moms[0]
inpa = lstm.be.array(inp)
# run neon fprop
lstm.configure((input_size, seq_len))
lstm.prev_layer = True # Hack to force allocating a delta buffer
lstm.allocate()
lstm.set_deltas([lstm.be.iobuf(lstm.in_shape)])
lstm.fprop(inpa)
# reference numpy LSTM
lstm_ref = RefLSTM()
WLSTM = lstm_ref.init(input_size, hidden_size)
# make ref weights and biases with neon model
WLSTM[0, :] = lstm.b.get().T
WLSTM[1:input_size + 1, :] = lstm.W_input.get().T
WLSTM[input_size + 1:] = lstm.W_recur.get().T
# transpose input X and do fprop
inp_ref = inp.copy().T.reshape(seq_len, batch_size, input_size)
(Hout_ref, cprev, hprev, batch_cache) = lstm_ref.forward(inp_ref, WLSTM)
# the output needs transpose as well
Hout_ref = Hout_ref.reshape(seq_len * batch_size, hidden_size).T
IFOGf_ref = batch_cache['IFOGf'].reshape(seq_len * batch_size,
hidden_size * 4).T
Ct_ref = batch_cache['Ct'].reshape(seq_len * batch_size, hidden_size).T
# compare results
neon_logger.display('====Verifying IFOG====')
assert allclose_with_out(lstm.ifog_buffer.get(),
IFOGf_ref,
rtol=0.0,
atol=1.5e-5)
neon_logger.display('====Verifying cell states====')
assert allclose_with_out(lstm.c_act_buffer.get(),
Ct_ref,
rtol=0.0,
atol=1.5e-5)
neon_logger.display('====Verifying hidden states====')
assert allclose_with_out(lstm.outputs.get(),
Hout_ref,
rtol=0.0,
atol=1.5e-5)
neon_logger.display('fprop is verified')
# now test the bprop
# generate random deltas tensor
deltas = np.random.randn(*hidden_shape)
lstm.bprop(lstm.be.array(deltas))
# grab the delta W from gradient buffer
dWinput_neon = lstm.dW_input.get()
dWrecur_neon = lstm.dW_recur.get()
db_neon = lstm.db.get()
deltas_ref = deltas.copy().T.reshape(seq_len, batch_size, hidden_size)
(dX_ref, dWLSTM_ref, dc0_ref,
dh0_ref) = lstm_ref.backward(deltas_ref, batch_cache)
dWrecur_ref = dWLSTM_ref[-hidden_size:, :]
dWinput_ref = dWLSTM_ref[1:input_size + 1, :]
db_ref = dWLSTM_ref[0, :]
dX_ref = dX_ref.reshape(seq_len * batch_size, input_size).T
# compare results
neon_logger.display('Making sure neon LSTM match numpy LSTM in bprop')
neon_logger.display('====Verifying update on W_recur====')
assert allclose_with_out(dWrecur_neon,
dWrecur_ref.T,
rtol=0.0,
atol=1.5e-5)
neon_logger.display('====Verifying update on W_input====')
assert allclose_with_out(dWinput_neon,
dWinput_ref.T,
rtol=0.0,
atol=1.5e-5)
neon_logger.display('====Verifying update on bias====')
assert allclose_with_out(db_neon.flatten(), db_ref, rtol=0.0, atol=1.5e-5)
neon_logger.display('====Verifying output delta====')
assert allclose_with_out(lstm.out_deltas_buffer.get(),
dX_ref,
rtol=0.0,
atol=1.5e-5)
neon_logger.display('bprop is verified')
return
def check_lstm(seq_len,
input_size,
hidden_size,
batch_size,
init_func,
return_seq=True,
backward=False,
reset_cells=False,
num_iter=2):
Cin = ng.make_axis(input_size, name='Feature')
REC = ng.make_axis(seq_len, name='REC')
N = ng.make_axis(batch_size, name='N')
with ExecutorFactory() as ex:
np.random.seed(0)
inp_ng = ng.placeholder([Cin, REC, N])
lstm_ng = LSTM(hidden_size,
init_func,
activation=Tanh(),
gate_activation=Logistic(),
reset_cells=reset_cells,
return_sequence=return_seq,
backward=backward)
out_ng = lstm_ng(inp_ng)
fprop_neon_fun = copier(ex.executor((out_ng, lstm_ng.h_init), inp_ng))
gates = ['i', 'f', 'o', 'g']
Wxh_neon_fun = copier_T(
ex.executor(list(lstm_ng.W_input[k] for k in gates)))
Whh_neon_fun = copier_T(
ex.executor(list(lstm_ng.W_recur[k] for k in gates)))
bh_neon_fun = copier(ex.executor(list(lstm_ng.b[k] for k in gates)))
fprop_neon_list = []
input_value_list = []
for i in range(num_iter):
# fprop on random inputs
input_value = rng.uniform(-1, 1, inp_ng.axes)
fprop_neon, h_init_neon = fprop_neon_fun(input_value)
if return_seq is True:
fprop_neon = fprop_neon[:, :, 0]
input_value_list.append(input_value)
fprop_neon_list.append(fprop_neon)
if reset_cells is False:
# look at the last hidden states
ng.testing.assert_allclose(fprop_neon[:, -1].reshape(-1, 1),
h_init_neon,
rtol=rtol,
atol=atol)
# after the rnn graph has been executed, can get the W values. Get copies so
# shared values don't confuse derivatives
# concatenate weights to i, f, o, g together (in this order)
Wxh_neon = Wxh_neon_fun()
Whh_neon = Whh_neon_fun()
bh_neon = bh_neon_fun()
# reference numpy LSTM
lstm_ref = RefLSTM()
WLSTM = lstm_ref.init(input_size, hidden_size)
# make ref weights and biases with neon model
WLSTM[0, :] = np.concatenate(bh_neon)
WLSTM[1:input_size + 1, :] = np.concatenate(Wxh_neon, 1)
WLSTM[input_size + 1:] = np.concatenate(Whh_neon, 1)
# transpose input X and do fprop
fprop_ref_list = []
c0 = h0 = None
for i in range(num_iter):
input_value = input_value_list[i]
inp_ref = input_value.copy().transpose([1, 2, 0])
(Hout_ref, cprev, hprev,
batch_cache) = lstm_ref.forward(inp_ref, WLSTM, c0, h0)
if reset_cells is False:
c0 = cprev
h0 = hprev
# the output needs transpose as well
Hout_ref = Hout_ref.reshape(seq_len * batch_size, hidden_size).T
fprop_ref_list.append(Hout_ref)
for i in range(num_iter):
ng.testing.assert_allclose(fprop_neon_list[i],
fprop_ref_list[i],
rtol=rtol,
atol=atol)
def gradient_check_ref(seq_len,
input_size,
hidden_size,
batch_size,
epsilon=1.0e-5,
dtypeu=np.float64,
threshold=1e-4):
# this is a check of the reference code itself
# estimates the gradients by adding perturbations
# to the input and the weights and compares to
# the values calculated in bprop
# generate sparse random input matrix
NervanaObject.be.bsz = NervanaObject.be.batch_size = batch_size
input_shape = (seq_len, input_size, batch_size)
# hidden_shape = (seq_len, hidden_size, batch_size)
(inp_bl, nz_inds) = sparse_rand(input_shape,
frac=1.0 / float(input_shape[1]))
inp_bl = np.random.randn(*input_shape)
# convert input matrix from neon to ref code format
inp_bl = inp_bl.swapaxes(1, 2).astype(dtypeu)
# generate reference LSTM
lstm_ref = RefLSTM()
WLSTM = lstm_ref.init(input_size, hidden_size).astype(dtypeu)
# init parameters as done for neon
WLSTM = np.random.randn(*WLSTM.shape)
(Hout, cprev, hprev, cache) = lstm_ref.forward(inp_bl, WLSTM)
# scale Hout by random matrix...
rand_scale = np.random.random(Hout.shape) * 2.0 - 1.0
rand_scale = dtypeu(rand_scale)
# line below would be the loss function
# loss_bl = np.sum(rand_scale * Hout)
# run bprop, input deltas is rand_scale
(dX_bl, dWLSTM_bl, dc0, dh0) = lstm_ref.backward(rand_scale, cache)
grads_est = np.zeros(dX_bl.shape)
inp_pert = inp_bl.copy()
for pert_ind in range(inp_bl.size):
save_val = inp_pert.flat[pert_ind]
# add/subtract perturbations to input
inp_pert.flat[pert_ind] = save_val + epsilon
# and run fprop on perturbed input
(Hout_pos, cprev, hprev, cache) = lstm_ref.forward(inp_pert, WLSTM)
inp_pert.flat[pert_ind] = save_val - epsilon
(Hout_neg, cprev, hprev, cache) = lstm_ref.forward(inp_pert, WLSTM)
# calculate the loss on outputs
loss_pos = np.sum(rand_scale * Hout_pos)
loss_neg = np.sum(rand_scale * Hout_neg)
grads_est.flat[pert_ind] = 0.5 / float(epsilon) * (loss_pos - loss_neg)
# reset input
inp_pert.flat[pert_ind] = save_val
# assert that gradient estimates within rel threshold of
# bprop calculated deltas
assert allclose_with_out(grads_est, dX_bl, rtol=threshold, atol=0.0)
return