is_assignments/a1/code/main_t1.py

197 lines
6.5 KiB
Python

import pygad
import numpy as np
import time
# Create a maze class
global maze_ix
def fitness_func(path, solution_idx):
maze = mazes[maze_ix]
fitness = np.sum(path * maze.punish_matrix.reshape(-1))
path = path.reshape(maze.punish_matrix.shape)
if path[maze.start_pos] == 0:
fitness -= 10000
if path[maze.end_pos] == 0:
fitness -= 10000
if path[maze.start_pos] == 1 and path[maze.end_pos] == 1:
fitness += 100
if maze.ga_iteration >= 4000 and maze.shortest_path == []:
critical = True
else:
critical = False
# Check if there is a valid path
complete_path = maze.walk_through_maze(path, critical_situation=critical)
complete_path_len = len(complete_path)
# Set the first path found as the shotest one
if maze.shortest_path == [] and complete_path_len > 0:
maze.adjust_weights(complete_path)
print('First path found')
maze.shortest_path = complete_path
# Check if the current path is shorter than the shortest one
elif complete_path_len != 0 and complete_path_len < len(maze.shortest_path):
print('Found a better path')
maze.shortest_path = complete_path
maze.adjust_weights(complete_path)
maze.ga_iteration += 1
return fitness
class Maze:
def __init__(self, maze, start_pos, end_pos, punish_matrix, logfile, shortest_path):
self.maze = maze
self.start_pos = start_pos
self.end_pos = end_pos
self.punish_matrix = punish_matrix
self.shortest_path = shortest_path
self.ga_iteration = 0
self.start_time = 0
self.end_time = 0
self.logfile = logfile
def run_genetic_algorithm(self):
# Set global punish matrix
punish_matrix = self.punish_matrix
maze = self.maze
self.start_time = time.time()
ga_instance = pygad.GA(num_genes=punish_matrix.size,
num_generations=1000,
sol_per_pop=20,
num_parents_mating=15,
gene_type=int,
crossover_type="two_points",
fitness_func=fitness_func,
parent_selection_type="tournament",
keep_parents=-1,
allow_duplicate_genes=True,
parallel_processing=4,
gene_space=[0, 1])
ga_instance.run()
self.end_time = time.time()
solution, solution_fitness, solution_idx = ga_instance.best_solution()
self.log_experiment()
#print("The shortest path is", self.shortest_path, self.ga_iteration)
#self.print_shortest_path()
def walk_through_maze(self, solution_matrix, critical_situation):
queue = [[self.start_pos]]
def add_to_queue(full_path, x, y):
if (x,y) not in full_path:
full_path = full_path.copy()
full_path.append((x, y))
queue.append(full_path)
while queue != []:
full_path = queue.pop()
x, y = full_path[-1]
if(self.maze[x][y] == 'E'):
return full_path
if x + 1 < len(self.maze) :
if solution_matrix[x+1, y] == 1 and (critical_situation or (self.maze[x+1][y] == "." or self.maze[x+1][y] == "E")):
add_to_queue(full_path, x+1, y)
if x - 1 >= 0:
if solution_matrix[x-1, y] == 1 and (critical_situation or (self.maze[x-1][y] == "." or self.maze[x-1][y] == "E")):
add_to_queue(full_path, x-1, y)
if y + 1 < len(self.maze) :
if solution_matrix[x, y+1] == 1 and (critical_situation or(self.maze[x][y+1] == "." or self.maze[x][y+1] == "E")):
add_to_queue(full_path, x, y+1)
if y - 1 >= 0:
if solution_matrix[x, y-1] == 1 and (critical_situation or (self.maze[x][y-1] == "." or self.maze[x][y-1] == "E")):
add_to_queue(full_path, x, y-1)
return []
def adjust_weights(self, found_path):
for (x, y) in found_path:
self.punish_matrix[x,y] += 700
def print_maze(self):
for row in self.maze:
print(' '.join(row))
def print_shortest_path(self):
for (x, y) in self.shortest_path:
lst = list(self.maze[x])
lst[y] = 'X'
self.maze[x] = ''.join(lst)
self.print_maze()
def log_experiment(self):
with open(self.logfile, 'a') as f:
f.write(str(maze_ix) +',')
f.write(str(self.end_time - self.start_time) +',')
f.write(str(self.shortest_path))
f.write('\n')
f.flush()
f.close()
def read_mazes():
with open('./mazes_classic.txt', 'r') as f:
mazes = []
maze = []
for line in f:
if line == '\n':
mazes.append(maze)
maze = []
continue
maze.append(line.strip())
return mazes
def prepare_maze(maze_ix, mazes, LOGFILE):
maze = mazes[maze_ix]
punish_matrix = np.zeros((len(maze), len(maze)), dtype=np.int64)
start_index = 0, 0
end_index = 0, 0
treasures = []
# Initialize punish matrix and find start and end index
for i, x in enumerate(maze):
for j, y in enumerate(x):
if y == "#":
punish_matrix[i, j] = -1000
if y == ".":
punish_matrix[i, j] = +700
if y == "S":
start_index = i, j
if y == "E":
end_index = i, j
if y == "T":
treasures.append((i, j))
# Create maze class
maze = Maze(maze, start_index, end_index, punish_matrix, LOGFILE, [])
return maze
def prepare_log(LOGFILE):
with open(LOGFILE, 'a') as f:
f.write('Maze,Time,Shortest path')
f.write('\n')
f.flush()
f.close()
def main():
# Read mazes
global maze_ix, mazes
mazes = []
text_mazes = read_mazes()
LOGFILE = 'log_t1_classic.txt'
prepare_log(LOGFILE)
for i in range(len(text_mazes)):
print('MAZE: ', i)
maze_ix = i
maze = prepare_maze(i, text_mazes, LOGFILE)
mazes.append(maze)
maze.run_genetic_algorithm()
if __name__ == "__main__":
main()