def Opt2(tour: List[Location.Location]):
oldTour = tour.copy()
newTour = tour.copy()
shortestDist = Location.FindTourLength(tour)
i = 0
j = 0
ij = len(tour)**2
while (i < len(tour)):
j = i + 1
if miscGlobal.specialPrint == True:
Funcs.PrintProgressBar(i * j, ij)
while (j < len(tour)):
if (time.process_time() - miscGlobal.start
) > miscGlobal.maxTime: #A little bit spaghetti
if miscGlobal.specialPrint == True:
print()
return oldTour
newTour = oldTour.copy()
TwoOptSwap(i, j, oldTour, newTour)
# print('Elements: ' + str(len(newTour)))
newDist = Location.FindTourLength(newTour)
# print('CurDist: ' + str(newDist))
if (newDist < shortestDist):
oldTour = newTour
shortestDist = newDist
yield oldTour
# print("\tNew shorter dist: " + str(shortestDist))
j += 1
i += 1
if miscGlobal.specialPrint == True:
Funcs.PrintProgressBar(100, 100)
print()
return oldTour
def SimulatedAnneal(tour : List[Location.Location], temp : float = 1000000.0, coolRate : float = 0.0003, targetTmp : float = 0.001, maxIts : int = 10000000):
bestTour = tour
bestDist = Location.FindTourLength(tour)
currentTour = bestTour
currentDist = bestDist
#Initialise these once
tourIndex1 = 0
tourIndex2 = 0
totalIts = 0
while temp > targetTmp and totalIts < maxIts:
if (100 / maxIts * totalIts) % 1 == 0 and miscGlobal.specialPrint == True: #Only write to console when needed
Funcs.PrintProgressBar(totalIts, maxIts)
if (time.process_time() - miscGlobal.start) > miscGlobal.maxTime: #A little bit spaghetti
if miscGlobal.specialPrint == True:
print()
return bestTour
totalIts += 1
newTour = currentTour.copy()
while tourIndex1 == tourIndex2: #Make sure that these aren't the same
tourIndex1 = random.randint(0, len(newTour) - 1)
tourIndex2 = random.randint(0, len(newTour) - 1)
#Swap the locations
Location.Swap(newTour, tourIndex1, tourIndex2)
newDist = Location.FindTourLength(newTour)
if AcceptProbs(currentDist, newDist, temp) : #Should we accept this new tour
currentTour = newTour
currentDist = newDist
# print('New tour dist: ' + str(currentDist))
if newDist < bestDist:
bestTour = newTour
bestDist = newDist
yield newTour
tourIndex1 = tourIndex2 #Makes them both equal so they will be recalculated
temp *= 1 - coolRate
# print(temp)
if miscGlobal.specialPrint == True:
Funcs.PrintProgressBar(100, 100)
print()
return bestTour
def SolveProblem(problemText: str, problemName: str, maxTime: float):
miscGlobal.maxTime = float(maxTime)
path = []
# print(Parse(problemText))
path = Parse(problemText)
path = NearestNeighbour(path)
path = TwoOpt(path)
path = SimulatedAnnealing(path)
if miscGlobal.specialPrint == True:
print('\nComputation time: ' +
str(time.process_time() - miscGlobal.start))
print('Total path length: ' + str(Location.FindTourLength(path)))
else:
Funcs.PrintData(problemName, Location.FindTourLength(path), path)
return path
def TwoOpt(path: List[Location.Location]):
#2Opt
if miscGlobal.specialPrint == True:
print('Opt2 Results:')
pathLenDiff = 10
pathLenDiffThreshold = 0.001
lastLength = Location.FindTourLength(path)
#If the path_delta < 1, it's not worth calculating anymore
while pathLenDiff >= pathLenDiffThreshold and (
time.process_time() - miscGlobal.start) < miscGlobal.maxTime:
for newPath in Opt2.Opt2(path):
yield newPath
path = newPath
newLength = Location.FindTourLength(path)
pathLenDiff = lastLength - newLength #Calculate this once
if miscGlobal.specialPrint == True:
print('Made path shorter by: ' + str(lastLength - newLength))
lastLength = newLength
if miscGlobal.specialPrint == True:
Funcs.PrintTour(path)
return path
if not DataBaseInterface.DoesProblemExist(problemName):
print(DataBaseInterface.AddProblem(sys.argv[3], problemName))
else:
print("PROBLEM ALREADY EXISTS")
elif len(sys.argv) >= 4 and sys.argv[
2] == 'SOLVE': #> python TSP_db.py problemName SOLVE maxSolveTime
if DataBaseInterface.DoesProblemExist(problemName):
solution = tsp.SolveProblem(
DataBaseInterface.GetProblem(problemName), \
problemName,
sys.argv[3]
)
DataBaseInterface.AddSolution(
problemName, \
Funcs.TourToIDText(solution), \
Location.FindTourLength(solution), \
"Test algorithm" \
)
else:
print(f"Problem '{problemName}' does not exist")
# print(DataBaseInterface.RetrieveProblemInfo(sys.argv[1]))
elif len(sys.argv) >= 3 and sys.argv[
2] == 'FETCH': #> python TSP_db.py problemName FETCH
if DataBaseInterface.DoesSolutionExist(problemName):
print(DataBaseInterface.GetSolution(problemName))
else:
print(f"Solution for problem '{problemName}' does not yet exist")
elif len(sys.argv) >= 3 and sys.argv[2] == 'PROBLEMEXISTS':
print(
'TRUE' if DataBaseInterface.DoesProblemExist(problemName) else 'FALSE')
elif len(sys.argv) >= 3 and sys.argv[2] == 'SOLEXISTS':
def SaveToSolution(any):
DataBaseInterface.AddSolution(miscGlobal.name, Funcs.TourToIDText(miscGlobal.tour), \
Location.FindTourLength(miscGlobal.tour), miscGlobal.algorithmChoice.name)
def TourToText(tour : List[Location.Location]):
text = 'Length: ' + str(Location.FindTourLength(tour)) + '\n'
for n in tour :
text += f"{n._id}\t{n._xpos}\t{n._ypos}\n"
text += f"-1\t{tour[0]._xpos}\t{tour[0]._ypos}\n" #Add first
return text
