Lower Triangular and Upper Triangular matrices in Java

🔷 Definitions

  1. Lower Triangular Matrix:

    • All elements above the main diagonal are 0.

    • For any cell (i, j), if j > i, set value to 0.

  2. Upper Triangular Matrix:

    • All elements below the main diagonal are 0.

    • For any cell (i, j), if i > j, set value to 0.


public class TriangularMatrix {


    // Function to print Lower Triangular Matrix

    static void printLowerTriangular(int[][] matrix) {

        int n = matrix.length;

        System.out.println("Lower Triangular Matrix:");

        for (int i = 0; i < n; i++) {

            for (int j = 0; j < n; j++) {

                if (j > i)

                    System.out.print("0 ");

                else

                    System.out.print(matrix[i][j] + " ");

            }

            System.out.println();

        }

    }


    // Function to print Upper Triangular Matrix

    static void printUpperTriangular(int[][] matrix) {

        int n = matrix.length;

        System.out.println("Upper Triangular Matrix:");

        for (int i = 0; i < n; i++) {

            for (int j = 0; j < n; j++) {

                if (i > j)

                    System.out.print("0 ");

                else

                    System.out.print(matrix[i][j] + " ");

            }

            System.out.println();

        }

    }


    public static void main(String[] args) {

        int[][] matrix = {

            {1, 2, 3},

            {4, 5, 6},

            {7, 8, 9}

        };


        printLowerTriangular(matrix);

        printUpperTriangular(matrix);

    }

}



 Matrix =

[123456789]

Lower Triangular Matrix = [100450789]


Upper Triangular Matrix =

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