This commit is contained in:
ixaxaar 2017-11-27 23:44:21 +05:30
parent 33249133d9
commit 57b082d5f0
2 changed files with 71 additions and 43 deletions

View File

@ -35,50 +35,53 @@ class SparseMemory(nn.Module):
self.K = sparse_reads if self.mem_size > sparse_reads else self.mem_size
self.num_kdtrees = num_kdtrees
self.index_checks = index_checks
self.rebuild_indexes_after = rebuild_indexes_after
# self.rebuild_indexes_after = rebuild_indexes_after
self.index_reset_ctr = 0
# self.index_reset_ctr = 0
m = self.mem_size
w = self.cell_size
r = self.K
r = self.K + 1
if self.independent_linears:
self.read_keys_transform = nn.Linear(self.input_size, w)
self.write_key_transform = nn.Linear(self.input_size, w)
self.read_query_transform = nn.Linear(self.input_size, w)
self.write_vector_transform = nn.Linear(self.input_size, w)
self.interpolation_gate_transform = nn.Linear(self.input_size, w)
self.write_gate_transform = nn.Linear(self.input_size, 1)
else:
self.interface_size = (3 * w) + 1
self.interface_size = (2 * w) + r + 1
self.interface_weights = nn.Linear(self.input_size, self.interface_size)
self.I = cuda(1 - T.eye(m).unsqueeze(0), gpu_id=self.gpu_id) # (1 * n * n)
self.last_used_mem = 0
def rebuild_indexes(self, hidden):
def rebuild_indexes(self, hidden, force=False):
b = hidden['sparse'].shape[0]
if self.rebuild_indexes_after == self.index_reset_ctr or 'dict' not in hidden:
self.index_reset_ctr = 0
hidden['dict'] = [FLANN() for x in range(b)]
[
x.build_index(hidden['sparse'][n], algorithm='kdtree', trees=self.num_kdtrees, checks=self.index_checks)
for n, x in enumerate(hidden['dict'])
]
self.index_reset_ctr += 1
# if self.rebuild_indexes_after == self.index_reset_ctr or 'indexes' not in hidden:
# self.index_reset_ctr = 0
hidden['indexes'] = [FLANN() for x in range(b)]
[
x.build_index(hidden['sparse'][n], algorithm='kdtree', trees=self.num_kdtrees, checks=self.index_checks)
for n, x in enumerate(hidden['indexes'])
]
# self.index_reset_ctr += 1
return hidden
def reset(self, batch_size=1, hidden=None, erase=True):
m = self.mem_size
w = self.cell_size
b = batch_size
r = self.K + 1
if hidden is None:
hidden = {
# warning can be a huge chunk of contiguous memory
'sparse': np.zeros((b, m, w), dtype=np.float32),
'read_weights': cuda(T.zeros(b, 1, m).fill_(δ), gpu_id=self.gpu_id),
'write_weights': cuda(T.zeros(b, 1, m).fill_(δ), gpu_id=self.gpu_id)
'read_weights': cuda(T.zeros(b, 1, r).fill_(δ), gpu_id=self.gpu_id),
'write_weights': cuda(T.zeros(b, 1, m).fill_(δ), gpu_id=self.gpu_id),
'read_vectors': cuda(T.zeros(b, r, w).fill_(δ), gpu_id=self.gpu_id),
'last_used_mem': [0] * b
# 'read_positions': np.zeros((b, 1, r)).tolist()
}
# Build FLANN randomized k-d tree indexes for each batch
hidden = self.rebuild_indexes(hidden)
@ -86,6 +89,7 @@ class SparseMemory(nn.Module):
# hidden['memory'] = hidden['memory'].clone()
hidden['read_weights'] = hidden['read_weights'].clone()
hidden['write_weights'] = hidden['write_weights'].clone()
hidden['read_vectors'] = hidden['read_vectors'].clone()
if erase:
hidden = self.rebuild_indexes(hidden)
@ -93,26 +97,49 @@ class SparseMemory(nn.Module):
# hidden['memory'].data.fill_(δ)
hidden['read_weights'].data.fill_(δ)
hidden['write_weights'].data.fill_(δ)
hidden['read_vectors'].data.fill_(δ)
return hidden
def write(self, write_key, write_vector, write_gate, hidden):
# write_weights = write_gate * ( \
# interpolation_gate * hidden['read_weights'] + \
# (1 - interpolation_gate)*cuda(T.ones(hidden['read_weights'].size()), gpu_id=self.gpu_id) )
def write_into_memory(self, hidden):
read_vectors = hidden['read_vectors'].data.cpu().numpy()
positions = hidden['read_positions']
for p in positions:
hidden['sparse'][:, p, :] = read_vectors
hidden = self.rebuild_indexes(hidden)
# NOTE: we cycle the memory in case it gets exhausted
# TODO: make this based on a usage measure
hidden['last_used_mem'] = [positions[l][-1] + 1 if positions[l][-1] + 1 < self.mem_size else 0
for l in range(read_vectors.shape[0])]
return hidden
def write(self, interpolation_gate, write_vector, write_gate, hidden):
write_weights = write_gate.unsqueeze(1) * (
interpolation_gate * hidden['read_weights'] +
(1 - interpolation_gate) * cuda(T.ones(hidden['read_weights'].size()), gpu_id=self.gpu_id))
# no erasing and hence no erase matrix R_{t}
hidden['read_vectors'] = hidden['read_vectors'] + T.bmm(write_weights.transpose(1, 2), write_vector)
if 'read_positions' in hidden:
hidden = self.write_into_memory(hidden)
return hidden
def read_from_sparse_memory(self, sparse, dict, keys):
def read_from_sparse_memory(self, sparse, indexes, keys, last_used_mem):
keys = keys.data.cpu().numpy()
read_vectors = []
read_positions = []
read_weights = []
for batch in range(keys.shape[0]):
positions, distances = dict[batch].nn_index(keys[batch, 0, :], num_neighbors=self.K)
positions, distances = indexes[batch].nn_index(keys[batch, 0, :], num_neighbors=self.K)
# add an extra word which is the least used memory cell
# TODO: for now, we assume infinite memory
positions = list(positions[0] if self.K > 1 else positions) + [last_used_mem[batch]]
distances = list(distances[0] if self.K > 1 else distances) + [0]
distances = distances / max(distances)
positions = positions[0] if self.K > 1 else positions
read_vector = [sparse[batch, p] for p in list(positions)]
read_weights.append(distances)
@ -120,46 +147,47 @@ class SparseMemory(nn.Module):
read_positions.append(positions)
read_vectors = cudavec(np.array(read_vectors), gpu_id=self.gpu_id)
read_weights = cudavec(np.array(read_weights), gpu_id=self.gpu_id)
read_weights = cudavec(np.array(read_weights), gpu_id=self.gpu_id).unsqueeze(1).float()
return read_vectors, positions, read_weights
return read_vectors, read_positions, read_weights
def read(self, read_keys, hidden):
def read(self, read_query, hidden):
# sparse read
read_vectors, positions, read_weights = \
self.read_from_sparse_memory(hidden['sparse'], hidden['dict'], read_keys)
self.read_from_sparse_memory(hidden['sparse'], hidden['indexes'], read_query, hidden['last_used_mem'])
hidden['read_positions'] = positions
hidden['read_weights'] = read_weights
hidden['read_vectors'] = read_vectors
return read_vectors, hidden
return hidden['read_vectors'][:, :-1, :].contiguous(), hidden
def forward(self, ξ, hidden):
# ξ = ξ.detach()
m = self.mem_size
w = self.cell_size
r = self.K
r = self.K + 1
b = ξ.size()[0]
if self.independent_linears:
# r read keys (b * r * w)
read_keys = self.read_keys_transform(ξ).view(b, 1, w)
read_query = self.read_query_transform(ξ).view(b, 1, w)
# write key (b * 1 * w)
write_key = self.write_key_transform(ξ).view(b, 1, w)
# write vector (b * 1 * w)
write_vector = self.write_vector_transform(ξ).view(b, 1, w)
# write vector (b * 1 * w)
interpolation_gate = self.interpolation_gate_transform(ξ).view(b, 1, r)
# write gate (b * 1)
write_gate = F.sigmoid(self.write_gate_transform(ξ).view(b, 1))
else:
ξ = self.interface_weights(ξ)
# r read keys (b * w * r)
read_keys = ξ[:, :w].contiguous().view(b, 1, w)
read_query = ξ[:, :w].contiguous().view(b, 1, w)
# write key (b * w * 1)
write_key = ξ[:, w: 2*w].contiguous().view(b, 1, w)
write_vector = ξ[:, w: 2 * w].contiguous().view(b, 1, w)
# write vector (b * w)
write_vector = ξ[:, 2*w: 3*w].contiguous().view(b, 1, w)
interpolation_gate = ξ[:, 2 * w: 2 * w + r].contiguous().view(b, 1, r)
# write gate (b * 1)
write_gate = F.sigmoid(ξ[:, -1].contiguous()).unsqueeze(1).view(b, 1)
hidden = self.write(write_key, write_vector, write_gate, hidden)
return self.read(read_keys, hidden)
hidden = self.write(interpolation_gate, write_vector, write_gate, hidden)
return self.read(read_query, hidden)

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@ -87,9 +87,9 @@ def test_rnn_n():
num_layers = 3
num_hidden_layers = 5
dropout = 0.2
nr_cells = 12
nr_cells = 20
cell_size = 17
sparse_reads = 3
sparse_reads = 9
gpu_id = -1
debug = True
lr = 0.001
@ -131,7 +131,7 @@ def test_rnn_n():
assert target_output.size() == T.Size([27, 10, 100])
assert chx[0][0].size() == T.Size([num_hidden_layers,10,100])
# assert mhx['memory'].size() == T.Size([10,12,17])
assert rv.size() == T.Size([10, 51])
assert rv.size() == T.Size([10, 153])
def test_rnn_no_memory_pass():