Question

How to define, use and print 2D (two-dimensional) array (list) in Python

Answer 1

w, h = 3, 2

arr = []
for y in range(h):
    arr.append([0 for x in range(w)])

arr[0][0] = 3
arr[0][1] = 8
arr[0][2] = 1

arr[1][0] = 4
arr[1][1] = 6
arr[1][2] = 9

print(arr[0][0])
print(arr[1][1])
print(arr[1][2])


'''
run:

3
6
9

'''

 

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Answer 2

w, h = 3, 2

arr = []
for y in range(h):
    arr.append([0 for x in range(w)])

arr[0][0] = 3
arr[0][1] = 8
arr[0][2] = 1

arr[1][0] = 4
arr[1][1] = 6
arr[1][2] = 9

print('\n'.join([''.join(['{:4}'.format(item) for item in row]) for row in arr]))


'''
run:

   3   8   1
   4   6   9

'''

 

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Answer 3

w, h = 3, 2

arr = []
for y in range(h):
    arr.append([0 for x in range(w)])

arr[0][0] = 3
arr[0][1] = 8
arr[0][2] = 1

arr[1][0] = 4
arr[1][1] = 6
arr[1][2] = 9

for i in range(h):
    for j in range(w):
        print('{:4}'.format(arr[i][j]), end=" ")
    print('\n')


'''
run:

   3    8    1

   4    6    9 

'''

 

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Answer 4

w, h = 3, 2

arr = []
for y in range(h):
    arr.append([0 for x in range(w)])

arr[0][0] = 3
arr[0][1] = 8
arr[0][2] = 1

arr[1][0] = 4
arr[1][1] = 6
arr[1][2] = 9

for row in arr:
    for val in row:
        print('{:4}'.format(val), end=" ")
    print('\n')


'''
run:

   3    8    1

   4    6    9 

'''

 

70+ SQL courses for beginners and professionals