def main(argv):
coords, distances = tsplib.load(argv[1])
plot = plotting.TspPlot(coords)
solution, cost = nearest_tour(distances, len(distances))
plot.redraw_best(solution, cost)
print cost
while 1:
pass
def main(argv):
coords, distances = tsplib.load(argv[1])
plot = plotting.TspPlot(coords)
solution, cost = nearest_tour(distances, len(distances))
print cost
def calc_cost(solution):
return tsplib.calc_cost(solution, distances)
two_opt(solution, cost, len(distances), calc_cost, plot.redraw_best)
while 1:
pass
def main(argv):
coords, distances = tsplib.load(argv[1])
plot = plotting.TspPlot(coords)
solution, cost = nearest_tour(distances, len(distances))
print cost
def calc_cost(solution):
return tsplib.calc_cost(solution, distances)
two_opt(solution, cost, len(distances), calc_cost, plot.redraw_best)
while 1:
pass
def main():
filename = input('TSP Instance: ') #Get file input
tspfile = tsplib.load(filename) #Load the TSP file based upon user input
print("n = ", tspfile.vertex_count()) #Print out the # of vertices
start = time.perf_counter() #Get beginning time
result = tsp_algo(tspfile) #Find the optimal path
end = time.perf_counter() #Get end time
cost = cycle_weight(tspfile, result) #Compute the cost
#Prints out the result
print('Elapsed time: ' + str(end - start))
print('Optimal Cycle: ' + str(result))
print('Optimal Cost: ' + str(cost))
def main(argv):
alpha = float(argv[1])
coords, distances = tsplib.load(argv[2])
count = len(distances)
solution, best_cost = nearest_tour(distances, len(distances))
plot = plotting.TspPlot(coords, draw_guess=True)
print best_cost
penalties = numpy.copy(distances)
penalties[:] = 0.0
def calc_cost(solution):
cost = tsplib.calc_cost(solution, distances)
sol_pens = penalties[solution[:-1], solution[1:]]
gls_cost = (cost +
alpha *
(best_cost/count+1) *
(sol_pens.sum() + penalties[solution[-1], solution[0]]))
return gls_cost
def penalise(solution):
sol_dists = distances[solution[0:-1], solution[1:]]
sol_dists = numpy.append(sol_dists, (distances[solution[0], solution[-1]],))
sol_pens = penalties[solution[0:-1], solution[1:]]
sol_pens = numpy.append(sol_pens, (penalties[solution[0], solution[-1]],))
utility = sol_dists/(sol_pens+1)
index_a = numpy.argmax(utility)
index_b = index_a+1 if index_a != count-1 else 0
a = solution[index_a]
b = solution[index_b]
penalties[a,b] += 1.0
penalties[b,a] += 1.0
def redraw_guess(solution, cost):
cost = tsplib.calc_cost(solution, distances) # ugh
plot.redraw_guess(solution, cost)
gls_cost = cost = best_cost
best_solution = numpy.copy(solution)
plot.redraw_best(best_solution, cost)
while 1:
solution, gls_cost = two_opt(solution, gls_cost, len(distances), calc_cost, redraw_guess)
cost = tsplib.calc_cost(solution, distances)
if cost < best_cost:
print cost
best_cost = cost
best_solution[:] = solution
plot.redraw_best(best_solution, cost)
penalise(solution)
def main():
#Verify the correct number of command line arguments were used
if len(sys.argv) != 2:
print('error: you must supply exactly one arguments\n\n' +
'usage: python3 tsp.py <weighted_graph.xml.zip file>')
sys.exit(1)
#Capture the command line arguments
weighted_graph = sys.argv[1]
print('TSP Instance:') #Get file input
tspfile = tsplib.load(weighted_graph) #Load the TSP file based upon user input
print("n = ", tspfile.vertex_count()) #Print out the # of vertices
start = time.perf_counter() #Get beginning time
result = tsp_algo(tspfile) #Find the Hamiltonian cycle of minimum total weight
end = time.perf_counter() #Get end time
cost = cycle_weight(tspfile, result) #Compute the cost
#Prints out the result
print('Elapsed time: ' + str(end - start))
print('Optimal Cycle: ' + str(result))
print('Optimal Cost: ' + str(cost))
