Use cliques for != (#188)

* use cliques for !=
* fixed bug: all different should return false if infeasible due to not enough values
* using lp solver if specified
* geqset constraint
* use captured alldifferent constraint for pruning bounds
* simplify several a >= b with same a to GeqSetConstraint
* results2csvs for visualizing benchmarking
* simplify as option

Author: Wikunia

CHANGELOG.md

@@ -1,9 +1,15 @@
 # ConstrainSolver.jl - Changelog
 
-## v0.3.1
+## Unreleased
+- Use LP solver also for single variable objectives
+- Combine several `x != y` constraints into all different constraints
+- Combine several `a >= x` constraints with the same `a` into a vector constraints
+  - used for better bounds using all different constraints
+
+## v0.3.1 (16th of November 2020)
 - Added `copy` function for constraint structs for latest JuMP/MOI versions
 
-## v0.3.0
+## v0.3.0 (11th of July 2020)
 - Reified constraint [#171](https://github.com/Wikunia/ConstraintSolver.jl/pull/171)
 
 ## v0.2.2 (26th of June 2020)

Project.toml

@@ -7,6 +7,7 @@ version = "0.3.1"
 Formatting = "59287772-0a20-5a39-b81b-1366585eb4c0"
 JSON = "682c06a0-de6a-54ab-a142-c8b1cf79cde6"
 JuMP = "4076af6c-e467-56ae-b986-b466b2749572"
+LightGraphs = "093fc24a-ae57-5d10-9952-331d41423f4d"
 MathOptInterface = "b8f27783-ece8-5eb3-8dc8-9495eed66fee"
 MatrixNetworks = "4f449596-a032-5618-b826-5a251cb6dc11"
 Statistics = "10745b16-79ce-11e8-11f9-7d13ad32a3b2"
@@ -15,6 +16,7 @@ Statistics = "10745b16-79ce-11e8-11f9-7d13ad32a3b2"
 Formatting = "^0.4.1"
 JSON = "~0.18, ~0.19, ~0.20, ~0.21"
 JuMP = "^0.21.3"
+LightGraphs = "1"
 MathOptInterface = "^0.9.11"
 MatrixNetworks = "^1"
 julia = "1"

benchmark/benchmarks.jl

@@ -54,4 +54,4 @@ SUITE["graph_coloring"]["US_8+equal"] = @benchmarkable solve_us_graph_coloring(;
 SUITE["graph_coloring"]["US_50colors+equal"] = @benchmarkable solve_us_graph_coloring(;num_colors=50, equality=true) seconds=5
 SUITE["graph_coloring"]["US_50colors"] = @benchmarkable solve_us_graph_coloring(;num_colors=50, equality=false) seconds=5
 SUITE["graph_coloring"]["queen7_7"] = @benchmarkable color_graph(joinpath(dir, "benchmark/graph_color/data/queen7_7.col"), 7) seconds=10
-SUITE["graph_coloring"]["le450_5d"] = @benchmarkable color_graph(joinpath(dir, "benchmark/graph_color/data/le450_5d.col"), 5) seconds=10
+SUITE["graph_coloring"]["le450_5d"] = @benchmarkable color_graph(joinpath(dir, "benchmark/graph_color/data/le450_5d.col"), 5) seconds=30

benchmark/graph_color/cs.jl

@@ -1,16 +1,18 @@
-using ConstraintSolver, JuMP
+using ConstraintSolver, JuMP, GLPK
 CS = ConstraintSolver
 
 function main(filename; benchmark = false, time_limit=100)
-    m = Model(optimizer_with_attributes(CS.Optimizer, "time_limit"=>time_limit))
+    lp_optimizer = optimizer_with_attributes(GLPK.Optimizer, "msg_lev" => GLPK.GLP_MSG_OFF)
+    m = Model(optimizer_with_attributes(CS.Optimizer, "time_limit"=>time_limit, "lp_optimizer" => lp_optimizer))
 
     lines = readlines(filename)
     num_colors = 0
     x = nothing
     max_color = nothing
     degrees = nothing
     for line in lines
-        parts = split(line, " ")
+        isempty(line) && continue
+        parts = split(line)
         if parts[1] == "p"
             num_colors = parse(Int, parts[3])
             @variable(m, 1 <= max_color <= num_colors, Int)
@@ -36,6 +38,9 @@ function main(filename; benchmark = false, time_limit=100)
     optimize!(m)
 
     status = JuMP.termination_status(m)
-
-    print("$status, $(JuMP.objective_value(m)), $(JuMP.solve_time(m))")
+    if status == MOI.OPTIMAL
+        print("$status, $(JuMP.objective_value(m)), $(JuMP.solve_time(m))")
+    else
+        print("$status, NaN, $(time_limit)")
+    end
 end