How to insert a value in 2D random lists?

Question

I'm trying to make a minesweeper with python. Now I'm trying to insert 10 mines into the lists randomly. Please help me to figure it out!

import random
import numpy as np
from random import randint

#assign a value of mines and create 8 x 8 empty array.
mines = 1000
arr1 = np.empty((8,8))

#insert 10 mines into random lists.
z = 1

if z < 11 :
    np.append(arr1, np.array(random.randint[mines]))
    z = z + 1

Does this answer your question? [Non-repetitive random number in numpy](https://stackoverflow.com/questions/8505651/non-repetitive-random-number-in-numpy) — Mateen Ulhaq, Jun 06 '20 at 03:42

Kuldeep Singh Sidhu · Answer 1 · 2020-06-06T03:41:46.847

since you have a total of 64 places

get a random int in 0,63(total 64)

and figure out the x and y

import random
import numpy as np
from random import randint

#assign a value of mines and create 8 x 8 empty array.
mines = 1000
arr1 = np.empty((8,8))
print(arr1)

minesRemaining = 10
while minesRemaining > 0:
    r = randint (0,63)
    i = r//8
    j = r%8
    if arr1[i][j]!=1000:
        arr1[i][j]=1000
        minesRemaining-=1
print(arr1)

[[2.2588207e-316 0.0000000e+000 0.0000000e+000 0.0000000e+000
  0.0000000e+000 0.0000000e+000 0.0000000e+000 0.0000000e+000]
 [0.0000000e+000 0.0000000e+000 0.0000000e+000 0.0000000e+000
  0.0000000e+000 0.0000000e+000 0.0000000e+000 0.0000000e+000]
 [0.0000000e+000 0.0000000e+000 0.0000000e+000 0.0000000e+000
  0.0000000e+000 0.0000000e+000 0.0000000e+000 0.0000000e+000]
 [0.0000000e+000 0.0000000e+000 0.0000000e+000 0.0000000e+000
  0.0000000e+000 0.0000000e+000 0.0000000e+000 0.0000000e+000]
 [0.0000000e+000 0.0000000e+000 0.0000000e+000 0.0000000e+000
  0.0000000e+000 0.0000000e+000 0.0000000e+000 0.0000000e+000]
 [0.0000000e+000 0.0000000e+000 0.0000000e+000 0.0000000e+000
  0.0000000e+000 0.0000000e+000 0.0000000e+000 0.0000000e+000]
 [0.0000000e+000 0.0000000e+000 0.0000000e+000 0.0000000e+000
  0.0000000e+000 0.0000000e+000 0.0000000e+000 0.0000000e+000]
 [0.0000000e+000 0.0000000e+000 0.0000000e+000 0.0000000e+000
  0.0000000e+000 0.0000000e+000 0.0000000e+000 0.0000000e+000]]
[[1000.    0.    0.    0.    0.    0.    0.    0.]
 [   0.    0.    0. 1000.    0.    0.    0.    0.]
 [1000. 1000.    0.    0.    0.    0.    0.    0.]
 [   0. 1000.    0.    0.    0.    0.    0.    0.]
 [   0.    0.    0.    0.    0.    0. 1000.    0.]
 [   0.    0.    0. 1000.    0.    0.    0.    0.]
 [   0.    0.    0.    0. 1000.    0.    0.    0.]
 [1000.    0.    0.    0. 1000.    0.    0.    0.]]

score 1 · Answer 2 · answered Jun 06 '20 at 03:43

This will generate a minefield:

grid = np.zeros((8, 8), dtype=np.bool)
mask = np.random.choice(grid.size, 10, replace=False)
grid.reshape(-1)[mask] = True

One example output:

>>> grid
array([[False, False, False, False, False,  True, False,  True],
       [False, False, False, False, False, False,  True, False],
       [False,  True, False, False, False, False, False, False],
       [False,  True, False, False, False, False, False, False],
       [False, False, False, False, False, False,  True, False],
       [False, False, False, False, False, False, False, False],
       [False, False, False, False, False, False,  True, False],
       [False,  True,  True, False, False, False,  True, False]])

score 1 · Answer 3 · answered Jun 06 '20 at 03:47

1

foo = np.array(list(range(64))
bar = numpy.random.choice(foo, 10)
baz = np.zeros(64)
baz[bar] = 1000
baaz = reshape((8, 8))

answered Jun 06 '20 at 03:47

Igor Rivin

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How to insert a value in 2D random lists?

3 Answers3