def save_nodes(nodes: List[AbstractNode], path: Union[str, BinaryIO]) -> None:
"""Save an iterable of nodes into hdf5 format.
Args:
nodes: An iterable of connected nodes. All nodes have to connect within
`nodes`.
path: path to file where network is saved.
"""
if reachable(nodes) > set(nodes):
raise ValueError(
"Some nodes in `nodes` are connected to nodes not contained in `nodes`."
" Saving not possible.")
if len(set(nodes)) < len(list(nodes)):
raise ValueError(
'Some nodes in `nodes` appear more than once. This is not supported')
#we need to iterate twice and order matters
edges = list(get_all_edges(nodes))
nodes = list(nodes)
old_edge_names = {n: edge.name for n, edge in enumerate(edges)}
old_node_names = {n: node.name for n, node in enumerate(nodes)}
#generate unique names for nodes and edges
#for saving them
for n, node in enumerate(nodes):
node.set_name('node{}'.format(n))
for e, edge in enumerate(edges):
edge.set_name('edge{}'.format(e))
with h5py.File(path, 'w') as net_file:
nodes_group = net_file.create_group('nodes')
node_names_group = net_file.create_group('node_names')
node_names_group.create_dataset(
'names',
dtype=string_type,
data=np.array(list(old_node_names.values()), dtype=object))
edges_group = net_file.create_group('edges')
edge_names_group = net_file.create_group('edge_names')
edge_names_group.create_dataset(
'names',
dtype=string_type,
data=np.array(list(old_edge_names.values()), dtype=object))
for n, node in enumerate(nodes):
node_group = nodes_group.create_group(node.name)
node._save_node(node_group)
for edge in node.edges:
if edge.node1 == node and edge in edges:
edge_group = edges_group.create_group(edge.name)
edge._save_edge(edge_group)
edges.remove(edge)
#name edges and nodes back to their original names
for n, node in enumerate(nodes):
nodes[n].set_name(old_node_names[n])
for n, edge in enumerate(edges):
edges[n].set_name(old_edge_names[n])
def nodes(self) -> Set[BaseNode]:
"""All tensor-network nodes involved in the operator."""
return reachable(
get_all_nodes(self.out_edges + self.in_edges) | self.ref_nodes)