Python - How to find the maximum number comparing to all its neighbors

I have a problem to solve with a Python code.

• Input ( M ) = 2D array with integer numbers
• Output (T ) same 2D array but with 0 and 1.
• Ti,j = 1 if all the neighbors of the integer Mi,j (in the 8 possible directions) are STRICTLY smaller than the Mi,j.
• Otherwise, in the opposite case, Ti,j = 0 if there is at least one neighbor in the matrix M greater than or equal to Mij.

I try with this code but it doesn't return the correct T.

def findmaximun(M):
    # Write your code here
    r, c = len(M),len(M[0])
    T = [[1 for col in range(c)] for row in range(r)]
    for i in range(0,r):
        for j in range(0,c): 
            for k in [-1,0,1]:
                if i+k>=0 and i+k<r:
                    for l in [-1,0,1]:
                        if j+l>=0 and j+l<c and max(-i-k,0)!=max(-j-l,0):
                            if M[i][j] <= M[i+k][j+l]:
                                      T[i][j]=0                
    return(T)

my solution is very explicit. I'm sure there is a more elegant way of handling the edge cases, but it may not be as readable. Ideally one would use numpy for such a task. It's way faster and offers better indexing and array operations. Also instead of typing out idx explicitly, one could use itertools.

I validated the code with matplotlibs imshow

import random

r = 10
c = 15

M = []
for i in range(r):
    M.append([])
    for j in range(c):
        M[i].append(random.random())


def find_max(M):
    # Setup array dimensions and output array
    r, c = len(M), len(M[0])
    T = [[0 for col in range(c)] for row in range(r)]
    # iterate over array
    for i, row in enumerate(M):
        for j, elem in enumerate(row):
            # handle edge cases (literally!)
            if i == 0:
                if j==0:
                    idx = [(1,0), (1,1), (0,1)]
                elif j==c-1:
                    idx = [(1,0), (1,-1), (0,-1)]
                else:
                    idx = [(1,0), (1,1), (0,1), (1,-1), (0,-1)]
            elif i==r-1:
                if j==0:
                    idx = [(-1,0), (-1,1), (0,1)]
                elif j==c-1:
                    idx = [(-1,0), (-1,-1), (0,-1)]
                else:
                    idx = [(-1,0), (-1,1), (0,1), (-1,-1), (0,-1)]
            else:
                if j==0:
                    idx = [(-1,0), (-1,1), (0,1), (1,1), (1,0)]
                elif j==c-1:
                    idx = [(-1,0), (-1,-1), (0,-1), (1,-1), (1,0)]
                else:
                    idx = [(0,1), (1,1), (1,0), (1,-1), (0,-1), (-1,-1), (-1,0), (-1,1)]
            # get the neighbors
            neighbors = []
            for x, y in idx:
                neighbors.append(M[i + x][j + y])
            # calculate t    
            if elem > max(neighbors):
                T[i][j] = 1
    return T
T = find_max(M)