Question

我正在研究一种星形算法，如下所示，我的代码是手工编写的，我正在考虑制作100 * 100大小的网格。因此，手动编写它们太可怕了。我需要将起点设置在（0,0）位置，将目标设置在（99,99）位置。

我正在尝试使用下面的这一行制作网格

grid1 = [[0 for i in range(100)]for j in range(100)]

但是如何在不触摸起点和目标点的位置的情况下随机或不随机地向该网格分配障碍物呢？

这是在我的代码下面：

from __future__ import print_function
import random

grid = [[0, 1, 0, 0, 0, 0],
        [0, 1, 0, 0, 0, 0],#0 are free path whereas 1's are obstacles
        [0, 1, 0, 0, 0, 0],
        [0, 1, 0, 0, 1, 0],
        [0, 0, 0, 0, 1, 0]]

'''
heuristic = [[9, 8, 7, 6, 5, 4],
             [8, 7, 6, 5, 4, 3],
             [7, 6, 5, 4, 3, 2],
             [6, 5, 4, 3, 2, 1],
             [5, 4, 3, 2, 1, 0]]'''

init = [0, 0]
goal = [len(grid)-1, len(grid[0])-1] #all coordinates are given in format [y,x] 
cost = 1

drone_h = 60

#the cost map which pushes the path closer to the goal
heuristic = [[0 for row in range(len(grid[0]))] for col in range(len(grid))]
for i in range(len(grid)):    
    for j in range(len(grid[0])):            
        heuristic[i][j] = abs(i - goal[0]) + abs(j - goal[1])

        #if grid[i][j] == 1:
            #heuristic[i][j] = 99 #added extra penalty in the heuristic map
print(heuristic)
elevation = [[0 for row in range(len(grid[0]))] for col in range(len(grid))]
for i in range(len(grid)):    
    for j in range(len(grid[0])): 
        if grid[i][j] == 1:
            elevation[i][j] = random.randint(1,100)
        else:
            elevation[i][j] = 0



#the actions we can take
delta = [[-1, 0 ], # go up
         [ 0, -1], # go left
         [ 1, 0 ], # go down
         [ 0, 1 ]] # go right


#function to search the path
def search(grid,init,goal,cost,heuristic):

    closed = [[0 for col in range(len(grid[0]))] for row in range(len(grid))]# the referrence grid
    closed[init[0]][init[1]] = 1
    action = [[0 for col in range(len(grid[0]))] for row in range(len(grid))]#the action grid

    x = init[0]
    y = init[1]
    g = 0

    f = g + heuristic[init[0]][init[0]] + elevation[init[0]][init[0]]
    cell = [[f, g, x, y]]

    found = False  # flag that is set when search is complete
    resign = False # flag set if we can't find expand

    while not found and not resign:
        if len(cell) == 0:
            resign = True
            return "FAIL"
        else:
            cell.sort()#to choose the least costliest action so as to move closer to the goal
            cell.reverse()
            next = cell.pop()
            x = next[2]
            y = next[3]
            g = next[1]
            f = next[0]


            if x == goal[0] and y == goal[1]:
                found = True
            else:
                for i in range(len(delta)):#to try out different valid actions
                    x2 = x + delta[i][0]
                    y2 = y + delta[i][1]
                    if x2 >= 0 and x2 < len(grid) and y2 >=0 and y2 < len(grid[0]):
                        if closed[x2][y2] == 0 and grid[x2][y2] == 0 and elevation[x2][y2] < drone_h :
                            g2 = g + cost
                            f2 = g2 + heuristic[x2][y2] + elevation[x2][y2]
                            cell.append([f2, g2, x2, y2])
                            closed[x2][y2] = 1
                            action[x2][y2] = i
    invpath = []
    x = goal[0]
    y = goal[1]
    invpath.append([x, y])#we get the reverse path from here
    while x != init[0] or y != init[1]:
        x2 = x - delta[action[x][y]][0]
        y2 = y - delta[action[x][y]][1]
        x = x2
        y = y2
        invpath.append([x, y])

    path = []
    for i in range(len(invpath)):
        path.append(invpath[len(invpath) - 1 - i])
    print("ACTION MAP")
    for i in range(len(action)):
        print(action[i])

    return path

a = search(grid,init,goal,cost,heuristic)
for i in range(len(a)):
    print(a[i])

Answer 1

您可以随机分配网格，然后确保起点和终点都没有障碍物。对于相邻字段，您可以仅对这两个字段执行相同的操作。

import random
grid1 = [[random.randint(0,1) for i in range(100)]for j in range(100)]

# clear starting and end point of potential obstacles
grid1[0][0] = 0
grid1[99][99] = 0

如何在不手动编写障碍物的情况下将障碍物分配到网格？

1 个答案: