Merge branch 'master' of https://github.com/chkwon/TSPSolvers.jl

.github/workflows/ci.yml

@@ -0,0 +1,40 @@
+name: CI
+on:
+  push:
+    branches: [master]
+  pull_request:
+    types: [opened, synchronize, reopened]
+jobs:
+  test:
+    name: Julia ${{ matrix.version }} - ${{ matrix.os }} - ${{ matrix.arch }} - ${{ github.event_name }}
+    runs-on: ${{ matrix.os }}
+    strategy:
+      fail-fast: false
+      matrix:
+        version: ['1']  # Test against LTS and current minor release
+        os: [ubuntu-latest, macOS-latest, windows-latest] # macOS-latest, windows-latest
+        arch: [x64]
+    steps:
+      - uses: actions/checkout@v2
+      - uses: julia-actions/setup-julia@v1
+        with:
+          version: ${{ matrix.version }}
+          arch: ${{ matrix.arch }}
+      - uses: actions/cache@v1
+        env:
+          cache-name: cache-artifacts
+        with:
+          path: ~/.julia/artifacts
+          key: ${{ runner.os }}-test-${{ env.cache-name }}-${{ hashFiles('**/Project.toml') }}
+          restore-keys: |
+            ${{ runner.os }}-test-${{ env.cache-name }}-
+            ${{ runner.os }}-test-
+            ${{ runner.os }}-
+      # - name: Install dependencies
+      #   run: julia --project=. -e 'using Pkg; Pkg.add(url="""https://github.com/matago/TSPLIB.jl"""); Pkg.instantiate()' 
+      - uses: julia-actions/julia-buildpkg@v1
+      - uses: julia-actions/julia-runtest@v1
+      - uses: julia-actions/julia-processcoverage@v1
+      - uses: codecov/codecov-action@v1
+        with:
+          file: lcov.info

src/main.jl

@@ -22,7 +22,7 @@ const supported_algorithms = [
 ]
 
 
-function solve_tsp(dist_mtx::Matrix{Int}; algorithm="LKH", firstcity=1, kwargs...) 
+function solve_tsp(dist_mtx::Matrix{Int}; algorithm="LKH", firstcity=1, init_tour::Vector{Int}=Int[], kwargs...) 
     n = size(dist_mtx, 1)
 
     S = dist_mtx
@@ -66,7 +66,22 @@ function solve_tsp(dist_mtx::Matrix{Int}; algorithm="LKH", firstcity=1, kwargs..
         return tour, cost
 
     elseif algorithm == "TwoOpt"
-        init_tour = rand_tour_for_heuristics(size(S, 1); firstcity=firstcity)
+        if isempty(init_tour)
+            init_tour = rand_tour_for_heuristics(size(S, 1); firstcity=firstcity)
+        end
+
+        if length(init_tour) == n 
+            init_tour = shift_tour!(init_tour, firstcity)
+            push!(init_tour, firstcity)
+        end
+
+        @assert length(init_tour) == n + 1
+        @assert init_tour[1] == init_tour[end]
+
+        if init_tour[1] != firstcity 
+            @warn("The first city of the initial tour is not $firstcity. It will be ignored.")
+        end
+
         _tour, cost = TravelingSalesmanHeuristics.two_opt(S, init_tour; kwargs...)
         tour = _tour[1:end-1]
         return tour, cost

src/utils.jl

@@ -34,14 +34,15 @@ end
 function shift_tour!(tour::Vector{Int}, firstcity)
     if tour[1] != firstcity 
         idx = findfirst(x -> x==firstcity, tour)
-        circshift!(tour, idx - 1)
+        circshift!(tour, length(tour) - idx + 1)
     end
 end
 
 function rand_tour_for_heuristics(n::Int; firstcity=1)
     tour = shuffle(1:n)
     shift_tour!(tour, firstcity)
     push!(tour, firstcity) # TravelingSalesmanHeuristics requires the first node at the end of the tour again.
+
     return tour
 end
 

test/runtests.jl

@@ -3,5 +3,6 @@ using Test
 
 @testset "TSPSolvers.jl" begin
     # Write your tests here.
-    include("simple.jl")
+    include("test_shift_tour.jl")
+    include("test_simple_TSP.jl")
 end

test/test_shift_tour.jl

@@ -0,0 +1,14 @@
+using TSPSolvers
+using Test 
+using LinearAlgebra
+using Random 
+
+@testset "Test Shift Tour" begin
+    for _ in 1:10
+        n = rand(1:100)
+        tour = shuffle(1:n)
+        first_city = rand(1:n)
+        TSPSolvers.shift_tour!(tour, first_city)
+        @test tour[1] == first_city
+    end
+end