def _remove_edge_rhs(self, node1, node2):
"""Remove edge from the rhs of the graph."""
primitives.remove_edge(self.rhs, node1, node2)
for pn1 in keys_by_value(self.p_rhs, node1):
for pn2 in keys_by_value(self.p_rhs, node2):
if (pn1, pn2) in self.p.edges():
primitives.remove_edge(self.p, pn1, pn2)
def remove_edge_rhs(self, node1, node2):
"""Remove edge from the rhs of the graph."""
primitives.remove_edge(self.rhs, node1, node2)
for pn1 in keys_by_value(self.p_rhs, node1):
for pn2 in keys_by_value(self.p_rhs, node2):
print(pn1, pn2)
try:
primitives.remove_edge(self.p, pn1, pn2)
except GraphError:
continue
def inject_remove_edge(self, n1, n2):
"""Inject removal of an edge by the rule.
Parameters
----------
n1 : hashable
Id of an edge's source node in `lhs`.
n2 : hashable
Id of an edge's target node in `lhs`.
Raises
------
RuleError
If some of the nodes are not found in neither
`lhs` nor `p`, or if a corresponding edge in
`p` does not exist.
"""
# Find nodes in p mapping to n1 & n2
p_keys_1 = keys_by_value(self.p_lhs, n1)
p_keys_2 = keys_by_value(self.p_lhs, n2)
# n1 is actually a node from `p`
if len(p_keys_1) == 0:
if n1 in self.p.nodes():
p_keys_1 = [n1]
else:
raise RuleError(
"Node '%s' is not found in neither left-hand "
"side nor preserved part" % n2)
if len(p_keys_2) == 0:
if n2 in self.p.nodes():
p_keys_2 = [n2]
else:
raise RuleError(
"Node '%s' is not found in neither left-hand "
"side nor preserved part" % str(n2))
for k1 in p_keys_1:
for k2 in p_keys_2:
if (k1, k2) in self.p.edges():
primitives.remove_edge(self.p, k1, k2)
primitives.remove_edge(self.rhs, self.p_rhs[k1], self.p_rhs[k2])
else:
raise RuleError(
"Edge '%s->%s' does not exist in the preserved part"
% (k1, k2))
return
def remove_edge(self, n1, n2):
"""Remove edge from the graph."""
# Find nodes in p mapping to n1 & n2
p_keys_1 = keys_by_value(self.p_lhs, n1)
p_keys_2 = keys_by_value(self.p_lhs, n2)
# Remove edge from the preserved part & rhs of the rule
for k1 in p_keys_1:
if k1 not in self.p.nodes():
raise RuleError(
"Node with the id '%s' does not exist in "
"the preserved part" % k1
)
for k2 in p_keys_2:
if k2 not in self.p.nodes():
raise RuleError(
"Node with the id '%s' does not exist in "
"the preserved part" % k2
)
rhs_key_1 = self.p_rhs[k1]
rhs_key_2 = self.p_rhs[k2]
if self.p.is_directed():
if (k1, k2) not in self.p.edges():
raise RuleError(
"Edge '%s->%s' does not exist in the preserved "
"part of the rule " % (k1, k2)
)
if (rhs_key_1, rhs_key_2) not in self.rhs.edges():
raise RuleError(
"Edge '%s->%s' does not exist in the right hand "
"side of the rule " % (rhs_key_1, rhs_key_2)
)
primitives.remove_edge(self.p, k1, k2)
primitives.remove_edge(self.rhs, rhs_key_1, rhs_key_2)
else:
if (k1, k2) not in self.p.edges() and\
(k2, k1) not in self.p.edges():
raise RuleError(
"Edge '%s->%s' does not exist in the "
"preserved part of the rule " % (k1, k2)
)
if (rhs_key_1, rhs_key_2) not in self.rhs.edges() and\
(rhs_key_2, rhs_key_1) not in self.rhs.edges():
raise RuleError(
"Edge '%s->%s' does not exist in the right "
"hand side of the rule " % (rhs_key_1, rhs_key_2)
)
primitives.remove_edge(self.p, k1, k2)
return
def _propagate_rule_up(graph,
origin_typing,
rule,
instance,
p_origin,
p_typing,
inplace=False):
if inplace is True:
graph_prime = graph
else:
graph_prime = copy.deepcopy(graph)
if p_typing is None:
p_typing = {}
lhs_removed_nodes = rule.removed_nodes()
lhs_removed_node_attrs = rule.removed_node_attrs()
p_removed_edges = rule.removed_edges()
p_removed_edge_attrs = rule.removed_edge_attrs()
lhs_cloned_nodes = rule.cloned_nodes()
graph_prime_graph = id_of(graph.nodes())
graph_prime_origin = copy.deepcopy(origin_typing)
for lhs_node in rule.lhs.nodes():
origin_node = instance[lhs_node]
g_nodes = keys_by_value(origin_typing, origin_node)
for node in g_nodes:
if lhs_node in lhs_removed_nodes:
primitives.remove_node(graph_prime, node)
del graph_prime_graph[node]
del graph_prime_origin[node]
else:
graph_prime_origin[node] = origin_node
for lhs_node, p_nodes in lhs_cloned_nodes.items():
nodes_to_clone = keys_by_value(origin_typing, instance[lhs_node])
for node in nodes_to_clone:
if node in p_typing.keys():
p_nodes = p_typing[node]
for i, p_node in enumerate(p_nodes):
if i == 0:
graph_prime_origin[node] = p_origin[p_node]
graph_prime_graph[node] = node
else:
new_name = primitives.clone_node(graph_prime, node)
graph_prime_origin[new_name] = p_origin[p_node]
graph_prime_graph[new_name] = node
if len(p_nodes) == 0:
primitives.remove_node(graph_prime, node)
for lhs_node, attrs in lhs_removed_node_attrs.items():
nodes_to_remove_attrs = keys_by_value(origin_typing,
instance[lhs_node])
for node in nodes_to_remove_attrs:
primitives.remove_node_attrs(graph_prime, node, attrs)
for p_u, p_v in p_removed_edges:
us = keys_by_value(graph_prime_origin, p_origin[p_u])
vs = keys_by_value(graph_prime_origin, p_origin[p_v])
for u in us:
for v in vs:
if (u, v) in graph_prime.edges():
primitives.remove_edge(graph_prime, u, v)
for (p_u, p_v), attrs in p_removed_edge_attrs.items():
us = keys_by_value(origin_typing, p_origin[p_u])
vs = keys_by_value(origin_typing, p_origin[p_v])
for u in us:
for v in vs:
primitives.removed_edge_attrs(graph_prime, u, v, attrs)
return (graph_prime, graph_prime_graph, graph_prime_origin)
def _propagate_rule_to(graph, origin_typing, rule, instance, p_origin,
inplace=False):
if inplace is True:
graph_prime = graph
else:
graph_prime = copy.deepcopy(graph)
lhs_removed_nodes = rule.removed_nodes()
lhs_removed_node_attrs = rule.removed_node_attrs()
p_removed_edges = rule.removed_edges()
p_removed_edge_attrs = rule.removed_edge_attrs()
lhs_cloned_nodes = rule.cloned_nodes()
graph_prime_graph = id_of(graph.nodes())
graph_prime_origin = dict()
for lhs_node in rule.lhs.nodes():
origin_node = instance[lhs_node]
g_nodes = keys_by_value(
origin_typing, origin_node)
for node in g_nodes:
if lhs_node in lhs_removed_nodes:
primitives.remove_node(
graph_prime, node)
del graph_prime_graph[node]
else:
graph_prime_origin[node] = origin_node
for lhs_node, p_nodes in lhs_cloned_nodes.items():
nodes_to_clone = keys_by_value(origin_typing, instance[lhs_node])
for node in nodes_to_clone:
for i, p_node in enumerate(p_nodes):
if i == 0:
graph_prime_origin[node] = p_origin[p_node]
graph_prime_graph[node] = node
else:
new_name = primitives.clone_node(
graph_prime,
node)
graph_prime_origin[new_name] = p_origin[p_node]
graph_prime_graph[new_name] = node
for lhs_node, attrs in lhs_removed_node_attrs.items():
nodes_to_remove_attrs = keys_by_value(
origin_typing, instance[lhs_node])
for node in nodes_to_remove_attrs:
primitives.remove_node_attrs(
graph_prime,
node, attrs)
for p_u, p_v in p_removed_edges:
us = keys_by_value(graph_prime_origin, p_origin[p_u])
vs = keys_by_value(graph_prime_origin, p_origin[p_v])
for u in us:
for v in vs:
if (u, v) in graph_prime.edges():
primitives.remove_edge(
graph_prime, u, v)
for (p_u, p_v), attrs in p_removed_edge_attrs.items():
us = keys_by_value(origin_typing, p_origin[p_u])
vs = keys_by_value(origin_typing, p_origin[p_v])
for u in us:
for v in vs:
primitives.removed_edge_attrs(
graph_prime, u, v, attrs)
return (graph_prime, graph_prime_graph, graph_prime_origin)
def remove_edge_p(self, node1, node2):
"""Remove edge from the p of the graph."""
primitives.remove_edge(self.p, node1, node2)
def pullback_complement(a, b, d, a_b, b_d, inplace=False):
"""Find the final pullback complement from a->b->d.
Makes changes to d inplace.
"""
check_homomorphism(a, b, a_b, total=True)
check_homomorphism(b, d, b_d, total=True)
if not is_monic(b_d):
raise InvalidHomomorphism(
"Second homomorphism is not monic, "
"cannot find final pullback complement!"
)
if inplace is True:
c = d
else:
c = copy.deepcopy(d)
a_c = dict()
c_d = id_of(c.nodes())
# Remove/clone nodes
for b_node in b.nodes():
a_keys = keys_by_value(a_b, b_node)
# Remove nodes
if len(a_keys) == 0:
remove_node(c, b_d[b_node])
del c_d[b_d[b_node]]
# Keep nodes
elif len(a_keys) == 1:
a_c[a_keys[0]] = b_d[b_node]
# Clone nodes
else:
i = 1
for k in a_keys:
if i == 1:
a_c[k] = b_d[b_node]
c_d[b_d[b_node]] = b_d[b_node]
else:
new_name = clone_node(c, b_d[b_node])
a_c[k] = new_name
c_d[new_name] = b_d[b_node]
i += 1
# Remove edges
for (b_n1, b_n2) in b.edges():
a_keys_1 = keys_by_value(a_b, b_n1)
a_keys_2 = keys_by_value(a_b, b_n2)
if len(a_keys_1) > 0 and len(a_keys_2) > 0:
for k1 in a_keys_1:
for k2 in a_keys_2:
if d.is_directed():
if (k1, k2) not in a.edges() and\
(a_c[k1], a_c[k2]) in c.edges():
remove_edge(c, a_c[k1], a_c[k2])
else:
if (k1, k2) not in a.edges() and\
(k2, k1) not in a.edges():
if (a_c[k1], a_c[k2]) in d.edges() or\
(a_c[k2], a_c[k1]) in d.edges():
remove_edge(c, a_c[k1], a_c[k2])
# Remove node attrs
for a_node in a.nodes():
attrs_to_remove = dict_sub(
b.node[a_b[a_node]],
a.node[a_node]
)
remove_node_attrs(c, a_c[a_node], attrs_to_remove)
# removed_node_attrs[a_c[a_node]] = attrs_to_remove
# Remove edge attrs
for (n1, n2) in a.edges():
attrs_to_remove = dict_sub(
get_edge(b, a_b[n1], a_b[n2]),
get_edge(a, n1, n2)
)
remove_edge_attrs(c, a_c[n1], a_c[n2], attrs_to_remove)
# removed_edge_attrs[(a_c[n1], a_c[n2])] = attrs_to_remove
return (c, a_c, c_d)
def pullback_complement(a, b, d, a_b, b_d, inplace=False):
"""Find the final pullback complement from a->b->d.
Makes changes to d inplace.
"""
check_homomorphism(a, b, a_b, total=True)
check_homomorphism(b, d, b_d, total=True)
if not is_monic(b_d):
raise InvalidHomomorphism("Second homomorphism is not monic, "
"cannot find final pullback complement!")
if inplace is True:
c = d
else:
c = copy.deepcopy(d)
a_c = dict()
c_d = id_of(c.nodes())
# Remove/clone nodes
for b_node in b.nodes():
a_keys = keys_by_value(a_b, b_node)
# Remove nodes
if len(a_keys) == 0:
remove_node(c, b_d[b_node])
del c_d[b_d[b_node]]
# Keep nodes
elif len(a_keys) == 1:
a_c[a_keys[0]] = b_d[b_node]
# Clone nodes
else:
i = 1
for k in a_keys:
if i == 1:
a_c[k] = b_d[b_node]
c_d[b_d[b_node]] = b_d[b_node]
else:
new_name = clone_node(c, b_d[b_node])
a_c[k] = new_name
c_d[new_name] = b_d[b_node]
i += 1
# Remove edges
for (b_n1, b_n2) in b.edges():
a_keys_1 = keys_by_value(a_b, b_n1)
a_keys_2 = keys_by_value(a_b, b_n2)
if len(a_keys_1) > 0 and len(a_keys_2) > 0:
for k1 in a_keys_1:
for k2 in a_keys_2:
if d.is_directed():
if (k1, k2) not in a.edges() and\
(a_c[k1], a_c[k2]) in c.edges():
remove_edge(c, a_c[k1], a_c[k2])
else:
if (k1, k2) not in a.edges() and\
(k2, k1) not in a.edges():
if (a_c[k1], a_c[k2]) in d.edges() or\
(a_c[k2], a_c[k1]) in d.edges():
remove_edge(c, a_c[k1], a_c[k2])
# Remove node attrs
for a_node in a.nodes():
attrs_to_remove = dict_sub(b.node[a_b[a_node]], a.node[a_node])
remove_node_attrs(c, a_c[a_node], attrs_to_remove)
# removed_node_attrs[a_c[a_node]] = attrs_to_remove
# Remove edge attrs
for (n1, n2) in a.edges():
attrs_to_remove = dict_sub(get_edge(b, a_b[n1], a_b[n2]),
get_edge(a, n1, n2))
remove_edge_attrs(c, a_c[n1], a_c[n2], attrs_to_remove)
# removed_edge_attrs[(a_c[n1], a_c[n2])] = attrs_to_remove
return (c, a_c, c_d)