Routing Formulation

What is routing

• TSP: Single vehicle, visit all locations once (e.g. shortest tour).
• VRP: Multiple vehicles, capacity and/or time limits; assign orders to vehicles and sequence stops.
• PDP: Pickup and delivery pairs; pickup must be visited before the corresponding delivery.

Required questions (problem and data)

1. Problem type — TSP, VRP, or PDP?
2. Locations — How many? Depot(s)? Cost or distance between pairs (matrix or derived)?
3. Orders / tasks — Which locations must be visited? Demand or service per stop?
4. Fleet — Number of vehicles, capacity per vehicle (and per dimension if multiple), start/end locations?
5. Constraints — Time windows (earliest/latest arrival), service times, precedence (order A before B)?

Typical data

• Cost or distance matrix (or travel-time matrix).
• Order locations and, for VRP, demand per order.
• Vehicle capacities and optional time windows for vehicles and orders.