From f0b20fae13007e97bb03a1f2f53f9f2de0e564a4 Mon Sep 17 00:00:00 2001
From: msurl <masur101@hhu.de>
Date: Sat, 13 Jun 2020 17:55:45 +0200
Subject: [PATCH] corrected algorithm to add vertex separators lazily
---
.../k_hop_dom_set.py | 55 ++++++++++++++++---
1 file changed, 47 insertions(+), 8 deletions(-)
diff --git a/python/conda package/k_hop_dominating_set_gurobi/k_hop_dominating_set_gurobi/k_hop_dom_set.py b/python/conda package/k_hop_dominating_set_gurobi/k_hop_dominating_set_gurobi/k_hop_dom_set.py
index a64a893..5e12bc1 100755
--- a/python/conda package/k_hop_dominating_set_gurobi/k_hop_dominating_set_gurobi/k_hop_dom_set.py
+++ b/python/conda package/k_hop_dominating_set_gurobi/k_hop_dominating_set_gurobi/k_hop_dom_set.py
@@ -165,6 +165,44 @@ class ConnectedKHopDominatingSet(KHopDominatingSet):
ds = {i for i,x_i in enumerate(self.m.getVars()) if x_i.x > 0.5}
return ds
+ # Probably uncorrect version
+ # def elim_unconnectivity(model, where):
+ # if where == GRB.Callback.MIPSOL:
+ # vals = model.cbGetSolution(model._vars)
+ # ds = {i for i in model._vars.keys() if vals[i] > 0.5}
+
+ # G_prime_prime = model._G.subgraph(ds)
+ # if(not nx.is_connected(G_prime_prime)):
+ # C = [c for c in nx.algorithms.components.connected_components(G_prime_prime)]
+ # for i in range(len(C)-1):
+ # C_i = C[i]
+ # for j in range(i+1, len(C)):
+ # C_j = C[j]
+ # h = next(iter(C_i))
+ # l = next(iter(C_j))
+ # min_ij_sep = ConnectedKHopDominatingSet.min_ij_separator(model._G, h, l, C_i)
+ # model.cbLazy(gp.quicksum(model._vars[s] for s in min_ij_sep) >= model._vars[h] + model._vars[l] - 1)
+
+ # V1
+ # def elim_unconnectivity(model, where):
+ # if where == GRB.Callback.MIPSOL:
+ # vals = model.cbGetSolution(model._vars)
+ # ds = {i for i in model._vars.keys() if vals[i] > 0.5}
+
+ # G_prime_prime = model._G.subgraph(ds)
+ # if(not nx.is_connected(G_prime_prime)):
+ # C = [c for c in nx.algorithms.components.connected_components(G_prime_prime)]
+ # for i in range(len(C)):
+ # C_i = C[i]
+ # for j in range(len(C)):
+ # C_j = C[j]
+ # h = next(iter(C_i))
+ # l = next(iter(C_j))
+ # min_ij_sep = ConnectedKHopDominatingSet.min_ij_separator(model._G, h, l, C_i)
+ # if min_ij_sep:
+ # model.cbLazy(gp.quicksum(model._vars[s] for s in min_ij_sep) >= model._vars[h] + model._vars[l] - 1)
+
+ # V2
def elim_unconnectivity(model, where):
if where == GRB.Callback.MIPSOL:
vals = model.cbGetSolution(model._vars)
@@ -173,15 +211,16 @@ class ConnectedKHopDominatingSet(KHopDominatingSet):
G_prime_prime = model._G.subgraph(ds)
if(not nx.is_connected(G_prime_prime)):
C = [c for c in nx.algorithms.components.connected_components(G_prime_prime)]
- for i in range(len(C)-1):
+ for i in range(len(C)):
C_i = C[i]
- for j in range(i+1, len(C)):
+ for j in range(len(C)):
C_j = C[j]
h = next(iter(C_i))
l = next(iter(C_j))
min_ij_sep = ConnectedKHopDominatingSet.min_ij_separator(model._G, h, l, C_i)
- model.cbLazy(gp.quicksum(model._vars[s] for s in min_ij_sep) >= model._vars[h] + model._vars[l] - 1)
-
+ if min_ij_sep:
+ for w in C_i:
+ model.cbLazy(gp.quicksum(model._vars[s] for s in min_ij_sep) >= model._vars[w] + model._vars[l] - 1)
class RootedConnectecKHopDominatingSet(ConnectedKHopDominatingSet):
@@ -192,10 +231,10 @@ class RootedConnectecKHopDominatingSet(ConnectedKHopDominatingSet):
self.m.addConstr(self.nodes[root] >= 1)
# self.add_all_combinations_root_separators()
- print("neighborhood separators:")
- self.add_all_neighborhood_root_separators()
- print("single node separators:")
- self.add_single_root_separators()
+ # print("neighborhood separators:")
+ # self.add_all_neighborhood_root_separators()
+ # print("single node separators:")
+ # self.add_single_root_separators()
def add_single_root_separators(self):
number_of_found_separators = 0
--
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