how to create a 2d list in python code example

Example 1: how to create 2d list in python

o=[]
for i in range(0,rows):
    x=[]
    for j in range(0,cols):
        x.append(0)
    o.append(x)
#if you use [[0]*cols]*rows all rows will become the same list
#so editing in one row will edit all rows

Example 2: 2d array python

array = [[value] * lenght] * height

//example
array = [[0] * 5] * 10

print(array)

Example 3: python print 2d array as table

for row in A:
    for val in row:
        print '{:4}'.format(val),
    print

Example 4: python print 2d array as table

import numpy as np
print(np.matrix(A))

Example 5: print 2d list in one line

import itertools
arr = [[1, 2, 3], [3, 4, 5]]
res = list(itertools.chain(*arr))
print(" ".join(map(str, res)))
1 2 3 3 4 5