Strict Diagonal Dominance Check

Problem

Return True if matrix A is strictly diagonally dominant: in every row, the absolute diagonal entry is greater than the sum of the absolute off-diagonal entries.

Return False if A is not square or any row fails the test.

Hint

The inequality must be strict in every row; zero rows always fail.

Test cases

case 1

in: [[[2,1],[1,2]]]

expected: true

case 2

in: [[[1,2],[3,4]]]

expected: false

case 3

in: [[[0,0],[0,0]]]

expected: false

case 4

in: [[[5,1,-1],[0,3,1],[1,0,4]]]

expected: true

Starter codePython

def is_diagonally_dominant(A):
    # Your code here
    pass

4 test cases · run your code against them in the editor