/// <summary>
/// Test removing adding every customer at every position.
/// </summary>
public void DoTestAddRemoveComplete()
{
// create a new empty route.
const int count = 10;
for (int customerToRemove = 0; customerToRemove < count; customerToRemove++)
{
for (int customerToPlaceAfter = 0; customerToPlaceAfter < count; customerToPlaceAfter++)
{
if (customerToRemove != customerToPlaceAfter)
{
IRoute route = this.BuildRoute(true);
if (route != null)
{ // this part needs testing.
for (int customer = 0; customer < count; customer++)
{
route.InsertAfter(customer - 1, customer);
//route.InsertAfterAndRemove(customer - 1, customer, -1);
}
route.Remove(customerToRemove);
route.InsertAfter(customerToPlaceAfter, customerToRemove);
//route.InsertAfterAndRemove(customer_to_place_after, customer_to_remove, -1);
Assert.IsTrue(route.Contains(customerToPlaceAfter, customerToRemove));
Assert.AreEqual(count, route.Count);
var customersInRoute = new HashSet <int>(route);
Assert.AreEqual(customersInRoute.Count, route.Count);
}
}
}
}
}
/// <summary>
/// Removes a given customer.
/// </summary>
/// <param name="customer"></param>
/// <returns></returns>
public bool Remove(int customer)
{
if (customer == 0)
{
throw new Exception("Cannot remove depot from depot routes.");
}
return(_route.Remove(customer));
}
/// <summary>
/// Tests adding customers.
/// </summary>
public void DoTestRemove()
{
IMultiRoute multiRoute = this.BuildRoute(true);
Assert.AreEqual(0, multiRoute.Count);
int count = 10;
int routes = 3;
// test with initializing the routes empty.
var customersPerRoute = new List <List <int> >();
Assert.AreEqual(0, multiRoute.Count);
for (int routeIdx = 0; routeIdx < routes; routeIdx++)
{
customersPerRoute.Add(new List <int>());
int customerStart = (routeIdx * count);
IRoute route = multiRoute.Add();
for (int customer = customerStart; customer < customerStart + count; customer++)
{
customersPerRoute[routeIdx].Add(customer);
route.InsertAfter(customer - 1, customer);
//route.InsertAfterAndRemove(customer - 1, customer, -1);
}
}
// remove all the customers.
while (customersPerRoute.Count > 0)
{
int routeIdx = OsmSharp.Math.Random.StaticRandomGenerator.Get().Generate(customersPerRoute.Count);
int customerIdx = OsmSharp.Math.Random.StaticRandomGenerator.Get().Generate(customersPerRoute[routeIdx].Count);
int customer = customersPerRoute[routeIdx][customerIdx];
customersPerRoute[routeIdx].RemoveAt(customerIdx);
IRoute route = multiRoute.Route(routeIdx);
route.Remove(customer);
Assert.AreEqual(customersPerRoute[routeIdx].Count, route.Count);
Assert.AreEqual(customersPerRoute[routeIdx].Count == 0, route.IsEmpty);
Assert.AreEqual(true, route.IsRound);
Assert.AreEqual(route.First, route.Last);
if (customersPerRoute[routeIdx].Count == 0)
{
customersPerRoute.RemoveAt(routeIdx);
multiRoute.Remove(routeIdx);
}
}
}
/// <summary>
/// Tries to improve the existing route using CI and return true if succesful.
/// </summary>
/// <param name="problem"></param>
/// <param name="route"></param>
/// <param name="difference"></param>
/// <returns></returns>
public bool Improve(IProblemWeights problem, IRoute route, out double difference)
{
bool improvement = false;
difference = 0;
if (route.Count > 3)
{
// loop over all customers and try cheapest insertion.
for (int customer = 0; customer < problem.Size; customer++)
{
//string route_string = route.ToString();
//IRoute previous = route.Clone() as IRoute;
if (route.Contains(customer))
{
// remove customer and keep position.
int next = route.GetNeigbours(customer)[0];
route.Remove(customer);
// insert again.
ArbitraryInsertionSolver.InsertOne(problem, route, customer, out difference);
if (!route.IsValid())
{
throw new Exception();
}
if (route.GetNeigbours(customer)[0] != next &&
difference < 0)
{ // another customer was found as the best, improvement is succesful.
improvement = true;
break;
}
}
}
}
return(improvement);
}
/// <summary>
/// Test removing customers.
/// </summary>
public void DoTestRemove()
{
// create a new empty route.
const int count = 100;
IRoute route = this.BuildRoute(0, true);
var customers = new List <int>();
if (route != null)
{ // this part needs testing!
customers.Add(0);
for (int customer = 1; customer < count; customer++)
{
route.InsertAfter(customer - 1, customer);
//route.InsertAfterAndRemove(customer - 1, customer, -1);
customers.Add(customer);
}
// remove customers.
while (customers.Count > 0)
{
int customerIdx = OsmSharp.Math.Random.StaticRandomGenerator.Get().Generate(
customers.Count);
int customer = customers[customerIdx];
customers.RemoveAt(customerIdx);
route.Remove(customer);
Assert.AreEqual(customers.Count, route.Count);
Assert.AreEqual(customers.Count == 0, route.IsEmpty);
Assert.AreEqual(true, route.IsRound);
Assert.AreEqual(route.Last, route.First);
}
}
route = this.BuildRoute(true);
customers = new List <int>();
if (route != null)
{ // this part needs testing!
for (int customer = 0; customer < count; customer++)
{
route.InsertAfter(customer - 1, customer);
//route.InsertAfterAndRemove(customer - 1, customer, -1);
customers.Add(customer);
}
// remove customers.
while (customers.Count > 0)
{
int customerIdx = OsmSharp.Math.Random.StaticRandomGenerator.Get().Generate(
customers.Count);
int customer = customers[customerIdx];
customers.RemoveAt(customerIdx);
route.Remove(customer);
Assert.AreEqual(customers.Count, route.Count);
Assert.AreEqual(customers.Count == 0, route.IsEmpty);
Assert.AreEqual(true, route.IsRound);
Assert.AreEqual(route.Last, route.First);
}
}
}
/// <summary>
/// Applies a local search strategy.
/// </summary>
/// <param name="problem"></param>
/// <param name="route"></param>
/// <returns></returns>
public static void CalculateRePlaceOptHelper(
IProblemWeights problem, IRoute route)
{
//bool improvement = true;
//while (improvement)
//{
//// reset improvement flag.
//improvement = false;
// try re-placement of one customer.
int before = -1;
//int after = -1;
int found_customer = -1;
// loop over all customers and try to place it better.
HashSet <int> customers_to_place = new HashSet <int>(route);
foreach (int customer_to_place in customers_to_place)
{
// find the best place.
double current_cost = -1;
double other_cost = double.MaxValue;
int previous_before = -1;
int previous = -1;
foreach (int customer in route)
{
if (previous >= 0 && previous_before >= 0)
{
if (previous == customer_to_place)
{
current_cost = problem.Weight(previous_before, previous) +
problem.Weight(previous, customer);
}
else if (previous_before != customer_to_place &&
customer != customer_to_place)
{ // calculate the cost.
double cost = problem.Weight(previous_before, customer_to_place) +
problem.Weight(customer_to_place, previous);
if (cost < other_cost)
{
other_cost = cost;
before = previous_before;
//after = previous;
found_customer = customer;
}
}
}
previous_before = previous;
previous = customer;
}
// determine if the cost is better.
if (current_cost > other_cost)
{ // the current cost is better.
route.Remove(found_customer);
//route.InsertAfterAndRemove(before, found_customer, after);
route.InsertAfter(before, found_customer);
break;
}
else
{ // current cost is not better.
before = -1;
//after = -1;
found_customer = -1;
}
}
//if (found_customer >= 0)
//{ // a found customer.
// improvement = true;
//}
//}
}
/// <summary>
/// Tries to improve the existing route using CI and return true if succesful.
/// </summary>
/// <param name="problem"></param>
/// <param name="route"></param>
/// <param name="difference"></param>
/// <returns></returns>
public bool Improve(IProblemWeights problem, IRoute route, out double difference)
{
bool improvement = false;
difference = 0;
if (route.Count > 3)
{
// loop over all customers and try cheapest insertion.
for (int customer = 0; customer < problem.Size; customer++)
{
//string route_string = route.ToString();
//IRoute previous = route.Clone() as IRoute;
if (route.Contains(customer))
{
// remove customer and keep position.
int next = route.GetNeigbours(customer)[0];
route.Remove(customer);
// insert again.
ArbitraryInsertionSolver.InsertOne(problem, route, customer, out difference);
if (!route.IsValid())
{
throw new Exception();
}
if (route.GetNeigbours(customer)[0] != next
&& difference < 0)
{ // another customer was found as the best, improvement is succesful.
improvement = true;
break;
}
}
}
}
return improvement;
}
/// <summary>
/// Applies a local search strategy.
/// </summary>
/// <param name="problem"></param>
/// <param name="route"></param>
/// <returns></returns>
public static void CalculateRePlaceOptHelper(
IProblemWeights problem, IRoute route)
{
//bool improvement = true;
//while (improvement)
//{
//// reset improvement flag.
//improvement = false;
// try re-placement of one customer.
int before = -1;
int after = -1;
int found_customer = -1;
// loop over all customers and try to place it better.
HashSet<int> customers_to_place = new HashSet<int>(route);
foreach (int customer_to_place in customers_to_place)
{
// find the best place.
double current_cost = -1;
double other_cost = double.MaxValue;
int previous_before = -1;
int previous = -1;
foreach (int customer in route)
{
if (previous >= 0 && previous_before >= 0)
{
if (previous == customer_to_place)
{
current_cost = problem.Weight(previous_before, previous) +
problem.Weight(previous, customer);
}
else if (previous_before != customer_to_place &&
customer != customer_to_place)
{ // calculate the cost.
double cost = problem.Weight(previous_before, customer_to_place) +
problem.Weight(customer_to_place, previous);
if (cost < other_cost)
{
other_cost = cost;
before = previous_before;
after = previous;
found_customer = customer;
}
}
}
previous_before = previous;
previous = customer;
}
// determine if the cost is better.
if (current_cost > other_cost)
{ // the current cost is better.
route.Remove(found_customer);
//route.InsertAfterAndRemove(before, found_customer, after);
route.InsertAfter(before, found_customer);
break;
}
else
{ // current cost is not better.
before = -1;
after = -1;
found_customer = -1;
}
}
//if (found_customer >= 0)
//{ // a found customer.
// improvement = true;
//}
//}
}
