How can I make a square with a specified circumference and add margin?

byMR

December 16, 2021

I am trying to make a square path of a specified length:

I made a function – and if I put 20 then I get a 6×6 matrix.

How can I add a margin of 0’s of eg. 3 fields thickness?

like this

0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 1 1 1 1 1 1 0 0 0
0 0 0 1 1 1 1 1 1 0 0 0
0 0 0 1 1 1 1 1 1 0 0 0
0 0 0 1 1 1 1 1 1 0 0 0
0 0 0 1 1 1 1 1 1 0 0 0
0 0 0 1 1 1 1 1 1 0 0 0
0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0 0

def square(length): return [
    [1 for _ in range(length//4+1)]
    for _ in range(length//4+1)
]

for x in square(24):
    print(x)

>Solution :

Here’s one way. One caution here is that, because of the way I duplicated the zero rows, those are all the same list. If you modify one of the zero rows, it will modify all of them.

def square(length): 
    zeros = [0]*(length//4+7)
    sq = [zeros] * 3
    sq.extend( [
        ([0,0,0] + [1 for _ in range(length//4+1)] + [0,0,0] )
        for _ in range(length//4+1)
    ])
    sq.extend( [zeros]*3 )
    return sq

for x in square(24):
    print(x)

Here’s a numpy method.

import numpy as np
def square(length): 
    c = length//4+1
    sq = np.zeros((c+6,c+6)).astype(int)
    sq[3:c+3,3:c+3] = np.ones((c,c))
    return sq

print( square(24) )