def main():
read_write = TspRW() # create a read_write object
read_write.read_file(
raw_input('Enter file to read from: '
)) # reads all the coordinates of citties from an ASCII file
l = read_write.labels
c = read_write.coordinates
handle = Nearest_Neighbour(
l, c) # create a Nearest_neigbour class from the given vertices
# for each vertex
for i in handle.vertices:
handle.mark_unvisited_cities() # mark all the citites unvisited
handle.empty_tour() # empties the tour
handle.startcity = i # set the city to start city
handle.currentcity = handle.startcity # sets the start city to current city
handle.mark_visited() # marks the city visited
# while there is an unvisited city
while len(handle.coordinates) != 0:
handle.calculate_nearneighbor(
) # find the nearest neighbour for the current city
handle.add_currcity_tour() # adds the current city to the tour
handle.add_tourCost() # adds the cost to the tour
handle.currentcity = handle.nearestcity # sets nearest city to current city
handle.mark_visited() # marks the current city visited
e = Edge(handle.currentcity, handle.startcity
) # creates the last edge between the current and start city
handle.best_tour.add_edge(e) # add that last edge to best tour
# updates best_tour_so_far if the last tour was lest costly
if handle.cost_of_tour < handle.cost_of_best_tour_so_far:
handle.cost_of_best_tour_so_far = handle.cost_of_tour
handle.best_tour_so_far = handle.best_tour
handle.best_label_so_far = handle.best_label
handle.best_coordinates_so_far = handle.best_coordinates
# write the coordinates to an ASCII file with .tour extension
read_write.coordinates = handle.best_coordinates_so_far
read_write.labels = handle.best_label_so_far
read_write.write_file()
# print handle.best_tour_so_far
# print handle.cost_of_best_tour_so_far
# print handle.best_label_so_far
# print handle.best_coordinates_so_far
# for i in range(len(handle.best_label_so_far)):
# handle.best_label_so_far[i].pos = handle.best_coordinates_so_far
# The following two lines allows to swtich the layout of the graph displayed
layout = CartesianLayout(handle.best_tour_so_far)
# layout = RandomLayout(handle.best_tour_so_far)
# draw the graph
gw = GraphWorld()
gw.show_graph(handle.best_tour_so_far, layout)
gw.mainloop()
def main():
read_write = TspRW() # create a read_write object
read_write.read_file(raw_input('Enter file to read from: ')) # reads all the coordinates of citties from an ASCII file
l = read_write.labels
c = read_write.coordinates
handle = Nearest_Neighbour(l, c) # create a Nearest_neigbour class from the given vertices
# for each vertex
for i in handle.vertices:
handle.mark_unvisited_cities() # mark all the citites unvisited
handle.empty_tour() # empties the tour
handle.startcity = i # set the city to start city
handle.currentcity = handle.startcity # sets the start city to current city
handle.mark_visited() # marks the city visited
# while there is an unvisited city
while len(handle.coordinates)!= 0:
handle.calculate_nearneighbor() # find the nearest neighbour for the current city
handle.add_currcity_tour() # adds the current city to the tour
handle.add_tourCost() # adds the cost to the tour
handle.currentcity = handle.nearestcity # sets nearest city to current city
handle.mark_visited() # marks the current city visited
e = Edge(handle.currentcity, handle.startcity) # creates the last edge between the current and start city
handle.best_tour.add_edge(e) # add that last edge to best tour
# updates best_tour_so_far if the last tour was lest costly
if handle.cost_of_tour < handle.cost_of_best_tour_so_far :
handle.cost_of_best_tour_so_far = handle.cost_of_tour
handle.best_tour_so_far = handle.best_tour
handle.best_label_so_far = handle.best_label
handle.best_coordinates_so_far = handle.best_coordinates
# write the coordinates to an ASCII file with .tour extension
read_write.coordinates = handle.best_coordinates_so_far
read_write.labels = handle.best_label_so_far
read_write.write_file()
# print handle.best_tour_so_far
# print handle.cost_of_best_tour_so_far
# print handle.best_label_so_far
# print handle.best_coordinates_so_far
# for i in range(len(handle.best_label_so_far)):
# handle.best_label_so_far[i].pos = handle.best_coordinates_so_far
# The following two lines allows to swtich the layout of the graph displayed
layout = CartesianLayout(handle.best_tour_so_far)
# layout = RandomLayout(handle.best_tour_so_far)
# draw the graph
gw = GraphWorld()
gw.show_graph(handle.best_tour_so_far, layout)
gw.mainloop()
def main():
time.clock()
object = TwoOpt() # create a two-opt object
read_write = TspRW() # create a read_write object
read_write.read_file(raw_input('Enter file to read from: ')) # reads all the coordinates of citties from an ASCII file
object.labels = read_write.labels # store the labels in a list
object.coordinates = read_write.coordinates # store the coordinates in this list
numRound = int(raw_input('Enter the number of random graphs you want to generate: '))
roundTimes = int(raw_input('Enter the number of times you want to swap edges: '))
for i in range(numRound):
object.generate_rand_graph() # generate a random graph
for i in range(roundTimes):
object.generate_rand_vertices() # randomly generate two indices which have no common connection
object.find_random_edge() # generate two random edges from the given indices
object.find_new_edge() # find the new edge if swap were to happen.
dx_oldtour = object.cal_distance_of_edge(object.edge1) + object.cal_distance_of_edge(object.edge2) # difference in cost before swapping using two-opt
dx_newtour = object.cal_distance_of_edge(object.new_edge1) + object.cal_distance_of_edge(object.new_edge2) # difference in cost after adding two edges.
if dx_newtour < dx_oldtour:
object.remove_edges()
object.add_edge_reversely()
if object.costOfBestTour > object.costOfTour:
bestTour = object.tour
bestTour_vertices = object.tour_vertices
object.costOfBestTour = object.costOfTour
# write the tour in .tour ASCII file
read_write.coordinates = []
read_write.labels = []
for i in bestTour_vertices:
read_write.coordinates.append(i.pos)
for i in bestTour_vertices:
read_write.labels.append(i.label)
read_write.write_file()
print 'Run time: ', time.clock()
# The following two lines allows to switch the layout of the graph displayed
# layout = CartesianLayout(bestTour)
layout = RandomLayout(bestTour)
# layout = CircleLayout(bestTour)
# draw the graph
gw = GraphWorld()
gw.show_graph(bestTour, layout)
gw.mainloop()
def main():
time.clock()
object = TwoOpt() # create a two-opt object
read_write = TspRW() # create a read_write object
read_write.read_file(
raw_input('Enter file to read from: '
)) # reads all the coordinates of citties from an ASCII file
object.labels = read_write.labels # store the labels in a list
object.coordinates = read_write.coordinates # store the coordinates in this list
numRound = int(
raw_input('Enter the number of random graphs you want to generate: '))
roundTimes = int(
raw_input('Enter the number of times you want to swap edges: '))
for i in range(numRound):
object.generate_rand_graph() # generate a random graph
for i in range(roundTimes):
object.generate_rand_vertices(
) # randomly generate two indices which have no common connection
object.find_random_edge(
) # generate two random edges from the given indices
object.find_new_edge() # find the new edge if swap were to happen.
dx_oldtour = object.cal_distance_of_edge(
object.edge1) + object.cal_distance_of_edge(
object.edge2
) # difference in cost before swapping using two-opt
dx_newtour = object.cal_distance_of_edge(
object.new_edge1) + object.cal_distance_of_edge(
object.new_edge2
) # difference in cost after adding two edges.
if dx_newtour < dx_oldtour:
object.remove_edges()
object.add_edge_reversely()
if object.costOfBestTour > object.costOfTour:
bestTour = object.tour
bestTour_vertices = object.tour_vertices
object.costOfBestTour = object.costOfTour
# write the tour in .tour ASCII file
read_write.coordinates = []
read_write.labels = []
for i in bestTour_vertices:
read_write.coordinates.append(i.pos)
for i in bestTour_vertices:
read_write.labels.append(i.label)
read_write.write_file()
print 'Run time: ', time.clock()
# The following two lines allows to switch the layout of the graph displayed
# layout = CartesianLayout(bestTour)
layout = RandomLayout(bestTour)
# layout = CircleLayout(bestTour)
# draw the graph
gw = GraphWorld()
gw.show_graph(bestTour, layout)
gw.mainloop()
