Skip to content
Related Articles

Related Articles

Improve Article
Save Article
Like Article

Python Program to check if matrix is lower triangular

  • Last Updated : 17 Jan, 2022

Given a square matrix and the task is to check the matrix is in lower triangular form or not. A square matrix is called lower triangular if all the entries above the main diagonal are zero. 
 

Examples: 
 

Input : mat[4][4] = {{1, 0, 0, 0},
                     {1, 4, 0, 0},
                     {4, 6, 2, 0},
                     {0, 4, 7, 6}};
Output : Matrix is in lower triangular form.

Input : mat[4][4] = {{1, 0, 0, 0},
                     {4, 3, 0, 1},
                     {7, 9, 2, 0},
                     {8, 5, 3, 6}};
Output : Matrix is not in lower triangular form.

 

Python3




# Python3 Program to check 
# lower triangular matrix.
  
# Function to check matrix 
# is in lower triangular
def islowertriangular(M):
    for i in range(0, len(M)):
        for j in range(i + 1, len(M)):
            if(M[i][j] != 0): 
                    return False
    return True
      
# Driver function.
M = [[1,0,0,0],
     [1,4,0,0],
     [4,6,2,0],
     [0,4,7,6]]
  
if islowertriangular(M):
    print ("Yes")
else:
    print ("No")
      
# This code is contributed by Anurag Rawat

Output: 
 

Yes

Please refer complete article on Program to check if matrix is lower triangular for more details!

My Personal Notes arrow_drop_up
Recommended Articles
Page :

Start Your Coding Journey Now!