def subproblem(self, c, clusterproblem):
# return basic connectivityproblem
# (graph, agents, eagents, big_agents, reward_dict)
# induced by cluster c
agents = {
r: clusterproblem.graph.agents[r]
for r in self.agent_clusters[c]
}
static_agents = [
r for r in agents.keys() if r in clusterproblem.static_agents
]
# add childcluster stuff
addn_nodes = set()
for C in self.child_clusters[c]:
agents[self.submasters[C[0]]] = C[1]
static_agents.append(self.submasters[C[0]])
addn_nodes.add(C[1])
G = deepcopy(clusterproblem.graph)
del_nodes = set(
clusterproblem.graph.nodes) - self.subgraphs[c] - addn_nodes
G.remove_nodes_from(del_nodes)
G.init_agents(agents)
# basic rewards based on centrality
reward_dict = betweenness_centrality(nx.DiGraph(G))
norm = max(reward_dict.values())
if norm == 0:
norm = 1
reward_dict = {
v: clusterproblem.max_centrality_reward * val / norm
for v, val in reward_dict.items()
}
# initialize subproblem
return ConnectivityProblem(
graph=G,
static_agents=static_agents,
eagents=[r for r in agents if r in clusterproblem.eagents],
big_agents=[r for r in agents if r in clusterproblem.big_agents],
reward_dict=reward_dict,
)
def test_horiz2():
G = Graph()
connectivity_edges = [0, 1, 2, 3] # directed connectivity path (one way)
transition_edges = [0, 1, 2, 3] # directed transition path (one way)
# Add edges to graph
G.add_transition_path(transition_edges)
G.add_connectivity_path(connectivity_edges)
# Set initial position of agents
agent_positions = {0: 0, 1: 1, 2: 3} # agent:position
# Init agents in graphs
G.init_agents(agent_positions)
# Set up the connectivity problem
cp = ConnectivityProblem()
# Specify graph
cp.graph = G
# Specify time horizon
cp.T = 2
# Specify sources
cp.src = [2]
cp.static_agents = [0, 2]
if import_gurobi():
cp.solve_flow()
# positions of robot 0
np.testing.assert_equal(cp.traj[0, 0], 0)
np.testing.assert_equal(cp.traj[0, 1], 0)
np.testing.assert_equal(cp.traj[0, 2], 0)
# positions of robot 1
np.testing.assert_equal(cp.traj[1, 0], 1)
np.testing.assert_equal(cp.traj[1, 1], 2)
np.testing.assert_equal(cp.traj[1, 2], 1)
# positions of robot 2 (fixed)
np.testing.assert_equal(cp.traj[2, 0], 3)
np.testing.assert_equal(cp.traj[2, 1], 3)
np.testing.assert_equal(cp.traj[2, 2], 3)
def test_frontier_weighting():
n = 4
# Define a connectivity graph
G = Graph()
G.add_transition_path(list(range(n)))
G.add_connectivity_path(list(range(n)))
G.set_node_positions({i: (0, i) for i in range(n)})
frontiers = {0: 1, 1: 1, 2: 4, 3: 1}
G.set_frontiers(frontiers)
agent_positions = {0: 0, 1: 2, 2: 3}
G.init_agents(agent_positions)
# Set up the connectivity problem
cp = ConnectivityProblem()
cp.graph = G
cp.T = 6
cp.static_agents = []
cp.master = 0
cp.src = [2]
cp.snk = [1]
# Solve
if import_gurobi():
cp.solve_flow(master=True,
frontier_reward=True,
connectivity=True,
cut=True)
# Check solution
for t in range(3):
np.testing.assert_equal(cp.traj[0, t], [0, 1, 2, 2][t])
np.testing.assert_equal(cp.traj[1, t], 2)
np.testing.assert_equal(cp.traj[2, t], 3)
np.testing.assert_equal(cp.conn[0], set())
np.testing.assert_equal(cp.conn[1], set())
np.testing.assert_equal(cp.conn[2],
set([(2, 3, "master"), (3, 2, 2)]))
from cops.problem import ConnectivityProblem
from cops.animate import animate
from graph_examples import get_linear_graph
n = 4
G = get_linear_graph(n)
frontiers = {i: 1 for i in range(3)}
G.set_frontiers(frontiers)
agent_positions = {0: 0, 1: 2, 2: 3}
G.init_agents(agent_positions)
# Set up the connectivity problem
cp = ConnectivityProblem()
cp.graph = G
cp.T = 6
cp.static_agents = []
cp.master = 0
cp.src = [2]
cp.snk = [1]
# Solve
cp.solve_flow(master=True, frontier_reward=True, connectivity=True, cut=True, solver='gurobi')
# Animate solution
animate(G, cp.traj, cp.conn)
def test_master_comm():
n = 4 # size of graph
# Define a connectivity graph
G = Graph()
G.add_transition_path(list(range(n)))
G.add_connectivity_path(list(range(n)))
G.set_node_positions({i: (0, i) for i in range(n)})
G.set_frontiers({1: 1})
G.init_agents({0: 0, 1: 2, 2: 3})
# Set up the connectivity problem
cp = ConnectivityProblem()
cp.graph = G
cp.T = 5
cp.static_agents = []
cp.master = 0
cp.src = [2]
cp.snk = [1]
# Solve with master, without frontier rewards
if import_gurobi():
cp.solve_flow(frontier_reward=False,
master=True,
connectivity=True,
cut=False)
# Check solution
for t in range(6):
np.testing.assert_equal(cp.traj[0, t], 0 if t == 0 else 1)
np.testing.assert_equal(cp.traj[1, t], 2)
np.testing.assert_equal(cp.traj[2, t], 3)
np.testing.assert_equal(
cp.conn[t],
set([(1, 2, "master"), (2, 3, "master"),
(3, 2, 2)]) if t == 1 else set(),
)
cp.solve_flow(frontier_reward=True,
master=True,
connectivity=True,
cut=False)
# Check solution
for t in range(6):
np.testing.assert_equal(cp.traj[0, t], 0 if t == 0 else 1)
np.testing.assert_equal(cp.traj[1, t], 2 if t < 2 else 1)
np.testing.assert_equal(cp.traj[2, t], [3, 3, 2, 1, 1, 1][t])
np.testing.assert_equal(
cp.conn[t],
set([(1, 2, "master"), (2, 3, "master")]) if t == 1 else set())
# Solve without master, without frontier rewards
cp.solve_flow(frontier_reward=False,
master=False,
connectivity=True,
cut=False)
# Check solution
for t in range(6):
np.testing.assert_equal(cp.traj[0, t], 0)
np.testing.assert_equal(cp.traj[1, t], 2)
np.testing.assert_equal(cp.traj[2, t], 3)
np.testing.assert_equal(cp.conn[t],
set([(3, 2, 2)]) if t == 0 else set())
# Solve without master, with frontier rewards
cp.solve_flow(frontier_reward=True,
master=False,
connectivity=True,
cut=False)
# Check solution
for t in range(6):
np.testing.assert_equal(cp.traj[0, t], 0 if t == 0 else 1)
np.testing.assert_equal(cp.traj[1, t], 2 if t < 1 else 1)
np.testing.assert_equal(cp.traj[2, t], [3, 2, 1, 1, 1, 1][t])
np.testing.assert_equal(cp.conn[t], set())
static_agents = [0]
# MAIN-LOOP----------------------------------------------------------------------
while not G.is_known():
# find frontiers
frontiers = {v: 1 for v in G.nodes if G.is_frontier(v)}
G.set_frontiers(frontiers)
# create sub-graph
g = deepcopy(G)
unknown = [v for v in G.nodes if not G.nodes[v]["known"]]
g.remove_nodes_from(unknown)
# Process1-TRAVERSE TO FRONTIERS-------------------------------------------------
cp1 = ConnectivityProblem()
cp1.graph = g # graph
cp1.master = master # master_agent
cp1.static_agents = static_agents # static agents
cp1.graph.agents = agent_positions
cp1.src = []
cp1.snk = []
cp1.diameter_solve_flow(master=True, connectivity=False)
agent_positions = {r: cp1.traj[(r, cp1.T_sol)] for r in cp1.graph.agents}
problem_list.append(cp1)
# Process2-EXPLORE FRONTIERS-----------------------------------------------------
ep = ExplorationProblem()
ep.graph = G # full graph
ep.T = 8 # exploration time
ep.static_agents = static_agents # static agents