def test_get_sub_seed():
n = 100
seed = np.random.randint(2**31)
sub_seeds = []
for i in range(n):
sub_seeds.append(get_sub_seed(seed, i, n))
assert len(np.unique(sub_seeds)) == n
# Test the cached version
cache = {}
sub_seeds_cached = []
for i in range(n):
sub_seed, cache = get_sub_seed(seed, i, n, cache=cache)
sub_seeds_cached.append(sub_seed)
assert np.array_equal(sub_seeds, sub_seeds_cached)
def test_get_sub_seed():
n = 100
rs = np.random.RandomState()
state = rs.get_state()
sub_seeds = []
for i in range(n):
rs.set_state(state)
sub_seeds.append(get_sub_seed(rs, i, n))
assert len(np.unique(sub_seeds)) == n
def prepare_seed(*inputs, **kwinputs):
if 'random_state' in kwinputs:
# Get the seed for this batch, assuming np.RandomState instance
seed = kwinputs['random_state'].get_state()[1][0]
# Since we may not be the first operation to use this seed, lets generate a
# a sub seed using this seed
sub_seed_index = kwinputs.get('index_in_batch') or 0
kwinputs['seed'] = get_sub_seed(np.random.RandomState(seed), sub_seed_index)
return inputs, kwinputs
def rvs(self, size=None, random_state=None):
random_state = random_state or np.random
self.context.batch_size = size or 1
self.context.seed = get_sub_seed(random_state, 0)
loaded_net = self.client.load_data(self._rvs_net, self.context, batch_index=0)
batch = self.client.compute(loaded_net)
rvs = np.column_stack([batch[p] for p in self.parameter_names])
if self.dim == 1:
rvs = rvs.reshape(size or 1)
return rvs[0] if size is None else rvs
def load(cls, context, compiled_net, batch_index):
"""Add an instance of random state to the corresponding node.
Parameters
----------
context : ComputationContext
compiled_net : nx.DiGraph
batch_index : int
Returns
-------
net : nx.DiGraph
Loaded net, which is the `compiled_net` that has been loaded with data that
can depend on the batch_index.
"""
key = 'output'
seed = context.seed
if seed is 'global':
# Get the random_state of the respective worker by delaying the evaluation
random_state = get_np_random
key = 'operation'
elif isinstance(seed, (int, np.int32, np.uint32)):
# TODO: In the future, we could use https://pypi.python.org/pypi/randomstate to enable
# jumps?
sub_seed, context.sub_seed_cache = get_sub_seed(seed,
batch_index,
cache=context.sub_seed_cache)
random_state = np.random.RandomState(sub_seed)
else:
raise ValueError("Seed of type {} is not supported".format(seed))
# Assign the random state or its acquirer function to the corresponding node
node_name = '_random_state'
if compiled_net.has_node(node_name):
compiled_net.node[node_name][key] = random_state
return compiled_net
def load(cls, context, compiled_net, batch_index):
key = 'output'
seed = context.seed
if seed is 'global':
# Get the random_state of the respective worker by delaying the evaluation
random_state = get_np_random
key = 'operation'
elif isinstance(seed, (int, np.int32, np.uint32)):
random_state = np.random.RandomState(context.seed)
else:
raise ValueError("Seed of type {} is not supported".format(seed))
# Jump (or scramble) the state based on batch_index to create parallel separate
# pseudo random sequences
if seed is not 'global':
# TODO: In the future, we could use https://pypi.python.org/pypi/randomstate to enable jumps?
random_state = np.random.RandomState(get_sub_seed(random_state, batch_index))
_random_node = '_random_state'
if compiled_net.has_node(_random_node):
compiled_net.node[_random_node][key] = random_state
return compiled_net