def read_pathcollection(filename: str,
separator: str = ',',
frequency: bool = False,
directed: bool = True,
maxlines: int = None) -> PathCollection:
"""Read path in edgelist format
Reads data from a file containing multiple lines of *edges* of the form
"v,w,frequency,X" (where frequency is optional and X are arbitrary
additional columns). The default separating character ',' can be changed.
Parameters
----------
filename : str
path to edgelist file
separator : str
character separating the nodes
frequency : bool
is a frequency given? if ``True`` it is the last element in the
edge (i.e. ``a,b,2``)
directed : bool
are the edges directed or undirected
maxlines : int
number of lines to read (useful to test large files).
None means the entire file is read
"""
from pathpy.core.path import Path, PathCollection
nodes: dict = {}
edges: dict = {}
paths: dict = {}
with open(filename, 'r') as csv:
for n, line in enumerate(csv):
fields = line.rstrip().split(separator)
assert len(fields) >= 1, 'Error: empty line: {0}'.format(line)
if frequency:
path = tuple(fields[:-1])
freq = float(fields[-1])
else:
path = tuple(fields)
freq = 1.0
for node in path:
if node not in nodes:
nodes[node] = Node(node)
if len(path) == 1 and path not in paths:
paths[path] = Path(nodes[path[0]], frequency=freq)
else:
edge_list = []
for u, v in zip(path[:-1], path[1:]):
if (u, v) not in edges:
edges[(u, v)] = Edge(nodes[u], nodes[v])
edge_list.append(edges[(u, v)])
if path not in paths:
paths[path] = Path(*edge_list, frequency=freq)
if maxlines is not None and n >= maxlines:
break
ncoll = NodeCollection()
for node in nodes.values():
ncoll.add(node)
ecoll = EdgeCollection(nodes=ncoll)
for edge in edges.values():
ecoll._add(edge)
_paths = PathCollection(directed=directed, nodes=ncoll, edges=ecoll)
for _path in paths.values():
_paths._add(_path)
return _paths
def read_file(cls,
filename: str,
separator: str = ',',
frequency: bool = False,
directed: bool = True,
maxlines: int = None) -> None:
"""
Read path in edgelist format
Reads data from a file containing multiple lines of *edges* of the
form "v,w,frequency,X" (where frequency is optional and X are
arbitrary additional columns). The default separating character ','
can be changed.
Parameters
----------
filename : str
path to edgelist file
separator : str
character separating the nodes
frequency : bool
is a frequency given? if ``True`` it is the last element in the
edge (i.e. ``a,b,2``)
directed : bool
are the edges directed or undirected
maxlines : int
number of lines to read (useful to test large files).
None means the entire file is read
"""
nodes = {}
edges = {}
paths = {}
with open(filename, 'r') as f:
for n, line in enumerate(f):
fields = line.rstrip().split(separator)
assert len(fields) >= 2, 'Error: malformed line: {0}'.format(
line)
if frequency:
path = tuple(fields[:-1])
f = int(fields[-1])
else:
path = tuple(fields)
f = 1
for node in path:
if node not in nodes:
nodes[node] = Node(node)
edge_list = []
for u, v in zip(path[:-1], path[1:]):
if (u, v) not in edges:
edges[(u, v)] = Edge(nodes[u],
nodes[v],
uid=u + '-' + v)
edge_list.append(edges[(u, v)])
if path not in paths:
paths[path] = Path(*edge_list, frequency=f)
if maxlines is not None and n >= maxlines:
break
nc = NodeCollection()
nc.add(*nodes.values())
ec = EdgeCollection(nodes=nc)
for edge in edges.values():
ec._add(edge)
p = PathCollection(nodes=nc, edges=ec)
for path in paths.values():
p._add(path)
return p