# OR-Library

OR-Library is a collection of test data sets for a variety of OR problems.

A full list of the test data sets available in OR-Library can be found
here.

## Site-Dependent Multi-Trip Periodic Vehicle Routing Problem

There are currently 10 data files.
These files are sdmtpvrp1, sdmtpvrp2, ..., sdmtpvrp10
These data files are the ones considered in:
"A tabu search algorithm for the periodic vehicle routing problem
with multiple vehicle trips and accessibility restrictions"
by F. Alonso, M.J. Alvarez and J.E. Beasley,
Journal of the Operational Research Society vol.59, 2008, pp963-976
The format of data files is as described below.
The first line contains the following information:
n t |C| |P| m tt
where
n = number of customers
t = number of days of the period
|C| = total number of delivery-day patterns
|P| = total number of vehicle types
m = number of vehicles
tt = proportionality constant for travel time
The next line contains the information about the depot:
dx dy lt
where
dx = x coordinate of the depot
dx = y coordinate of the depot
lt = proportionality constant for load time
The next m lines contain, for each vehicle, the following information:
p Q D c
where
p = Vehicle type
Q = maximum load of a vehicle
D = maximum duration of a route
c = Operation cost per unit of distance travelled
The next n lines contain, for each customer, the following information:
x y q ut f a list1 e list2
where
x = x coordinate
y = y coordinate
q = demand
ut = proportionality constant for unload time
f = frequency of visit
a = number of possible visit combinations
list1 = list of all possible visit combinations
e = number of possible vehicle types
list 2 = list of all possible vehicle types
The next |C| lines contain, for each delivery-day pattern, the following information:
f list
where:
f = frequency of visit
list = list visit days
The proportionality constants are used to transform distance/load units into time units
Hence the time to travel between two customers is equal to the Euclidean distance between
them multiplied by the appropriate proportionality constant.
The time to load at the depot, or unload at a customer, is equal to the amount loaded/unloaded
multiplied by the appropriate proportionality constant.
The entire set of files is of size 200Kb (approximately).
Click here to access these files