def get_turtle_state_from(self, head):
turtle = Turtle()
root = self.get_root_from(head)
path = shortest_path(self.parentage, root, head)
for node in path:
turtle.move(node)
return turtle
def test_join_network(self):
"""
Tests various joins by path analysis
"""
md = MetaData()
table_one = Table("one", md, Column("pk", Integer, primary_key=True))
table_two = Table(
"two",
md,
Column("pk", Integer, primary_key=True),
Column("one_fk", Integer, ForeignKey("one.pk")),
)
network = join_network(md.tables)
self.assertListEqual(
[tbl.name for tbl in shortest_path(network, table_two, table_one)],
["two", "one"])
def fails():
shortest_path(network, table_one, table_two)
self.assertRaises(NetworkXNoPath, fails)
table_three = Table("three", md, Column("pk",
Integer,
primary_key=True),
Column("two_fk", Integer, ForeignKey("two.pk")))
table_four = Table("four", md, Column("pk", Integer, primary_key=True),
Column("three_fk", Integer, ForeignKey("three.pk")))
self.assertListEqual([
tbl.name for tbl in shortest_path(join_network(md.tables),
table_four, table_one)
], ["four", "three", "two", "one"])
table_five = Table("five", md, Column("pk", Integer, primary_key=True),
Column("one_fk", Integer, ForeignKey("one.pk")))
table_six = Table("six", md, Column("pk", Integer, primary_key=True),
Column("five_fk", Integer, ForeignKey("five.pk")))
self.assertListEqual([
tbl.name for tbl in shortest_path(join_network(md.tables),
table_six, table_one)
], ["six", "five", "one"])
def solve_instance(self, instance):
"""
Where the magic happens.
This method should return the solution (as a string) of the given instance.
"""
self.graph = nx.Graph()
self.add_nodes_to_graph(instance)
self.add_edges_to_graph(instance)
path = shortest_path(self.graph, instance.start, instance.end)
return "->".join(path)
def shortestPath(self, source: V, target: V) -> Optional[list]:
"""
"""
try:
path_nodes = shortest_path(self.graph,
source=source,
target=target)
path: list = [{} for x in range(0, len(path_nodes) - 1)]
for pos, _ in enumerate(path):
path[pos] = {path_nodes[pos], path_nodes[pos + 1]}
return path
except NetworkXNoPath:
return None
def find_cycle_with_edge_of_matching(graph: nx.Graph, matching: Dict[Any, Any]) -> List[Any]:
tmp_graph = copy.deepcopy(graph)
# Remove the edge so and find a path from a node of the edge to the other one.
# If a path is found, the circle is completed with the removed edge
for k, v in matching.items():
if not tmp_graph.has_edge(k, v):
# The graph could have been reduced
continue
tmp_graph.remove_edge(k, v)
try:
path = shortest_path(G=tmp_graph, source=v, target=k)
except nx.NetworkXNoPath:
tmp_graph.add_edge(k, v)
continue
else:
tmp_graph.add_edge(k, v)
return cast(List[Any], path)
# No cycle was found
raise nx.NetworkXNoCycle
def make_candidate_path_graph(drop_poles, candidate_segment_cost_graph):
g = nx.Graph()
for pole1, pole2 in combinations(drop_poles, 2):
pole1_id = pole1.id
pole2_id = pole2.id
pole1_xyz = pole1.geometry.coords[0]
pole2_xyz = pole2.geometry.coords[0]
line_coords = shortest_path(candidate_segment_cost_graph,
pole1_xyz,
pole2_xyz,
weight='cost')
line_cost = shortest_path_length(candidate_segment_cost_graph,
pole1_xyz,
pole2_xyz,
weight='cost')
g.add_edge(pole1_id,
pole2_id,
id='%s-%s' % (pole1_id, pole2_id),
path_type=None,
geometry=LineString(line_coords),
cost=line_cost)
return g
def shortest_path(self, from_node, to_node):
path = shortest_path(self.reachability, from_node, to_node)
return path
def compose_join(network,
loa_name,
table_name,
column_name,
loa_index_columns,
agg_fn="avg"):
"""
compose_join
Creates a list of operations that can be applied to a Query object, making
it retrieve data at a certain LOA
:param network: A networkx graph representing a database
:param loa_name: The name of the LOA to retrieve data at
:param table_name: The name of the table from which to retrieve the data
:param column_name: The name of the column to retrieve
:param agg_fn: If the retrieval op. needs to aggregate data, if will do so with this function
:returns: An iterator containing functions to be applied to a Query object
:raises QueryError: If table_name.column_name does not exist in the DB
:raises ConfigError: If the requested loa is not configured
"""
lookup = {tbl.name: tbl for tbl in network}
get_col_ref = lambda tbl, name: lookup[tbl].c[name] #.label(tbl+"_"+name)
loa_table = lookup[loa_name]
try:
column_ref = get_col_ref(table_name, column_name)
except KeyError as ke:
raise exceptions.QueryError(
f"{table_name}.{column_name} not found") from ke
index_columns_ref = []
for idx_table_name, idx_column_name in loa_index_columns:
try:
index_columns_ref.append(
get_col_ref(idx_table_name, idx_column_name))
except KeyError as ke:
raise exceptions.ConfigError(
f"Index column for {loa_table}"
f" {idx_table_name}.{idx_column_name} not found")
all_columns = list(set(index_columns_ref + [column_ref]))
names = [c.table.name + "_" + c.name for c in all_columns]
aggregates = False
# Compute joins (+ agg)
join = []
joined = set()
for idx, c in enumerate(all_columns):
try:
path = shortest_path(network, loa_table, c.table)
except NetworkXNoPath:
aggregates = True
path = shortest_path(network, c.table, loa_table)
path.reverse()
all_columns[idx] = getattr(sa.func, agg_fn)(c)
names[idx] = names[idx] + "_" + agg_fn
prev = loa_table
for table in path[1:]:
if table not in joined:
try:
con = network[prev][table]
join.append(
class_partial("join", table,
con["reference"] == con["referent"]))
except KeyError:
con = network[table][prev]
join.append(
class_partial("join", table,
con["referent"] == con["reference"]))
joined = joined.union({table})
else:
pass
prev = table
# Selects
all_columns = [col.label(name) for col, name in zip(all_columns, names)]
select = [class_partial("add_columns", col) for col in all_columns]
# Aggregation
if aggregates:
group_by = [class_partial("group_by", c) for c in index_columns_ref]
else:
group_by = []
logger.debug("%s selects", len(select))
logger.debug("%s joins", len(join))
logger.debug("%s groupbys", len(group_by))
return chain(select, [class_partial("select_from", loa_table)], join,
group_by)
def shortest_path_to_destination(self, origin: Location,
destination: Location) -> List[Location]:
path: List[Tuple[int]] = shortest_paths.shortest_path(
self._graph, origin.coordinates, destination.coordinates)
return [Location(node[0], node[1]) for node in path]
import networkx as nx
from networkx.algorithms.shortest_paths import shortest_path
with open("input.txt") as input_file:
lines = input_file.readlines()
g = nx.DiGraph()
for line in lines:
if ")" not in line:
continue
t, f = line.strip().split(")")
g.add_edge(f, t)
orbits = 0
for node in g.nodes:
if node == "COM":
continue
path = shortest_path(g, node, "COM")
orbits += len(path) - 1
print(orbits)
def fails():
shortest_path(network, table_one, table_two)
import networkx as nx
from networkx.algorithms.shortest_paths import shortest_path
with open("input.txt") as input_file:
lines = input_file.readlines()
g = nx.Graph()
for line in lines:
if ")" not in line:
continue
t, f = line.strip().split(")")
g.add_edge(f, t)
orbits = 0
path = shortest_path(g, "YOU", "SAN")
steps = len(path)-3
print(path)
print(steps)