# Check if matrix is lower triangular

Here given code implementation process.

/*
C Program
+ Check if matrix is lower triangular
*/
#include<stdio.h>
//Size of matrix
#define ROW 4
#define COL 4

//Display the element of given 2d matrix
void show_data(int matrix[][COL]) {

for (int i = 0; i < ROW; ++i) {

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

printf("%4d", matrix[i][j]);
}

printf("\n");
}

printf("\n");
}
//Check if given matrix is lower triangular or not
void lower_triangular(int matrix[ROW][COL])
{
int status=1;

for (int i = 0; i < COL && status==1; ++i)
{
for (int j = i+1; j < ROW && status==1; ++j)
{
if(matrix[i][j] != 0)
{
//When matrix is not lower triangular
status=0;
}
}

}
if(status==1)
{
printf("  Yes\n");
}
else
{
printf("  NO\n");
}

}
int main(){

int matrix[ROW][COL]=  {
{ 1, 0, 0, 0 },
{ 1, 2, 0, 0 },
{ 1, 2, 3, 0 },
{ 1, 2, 3, 4 }  };
show_data(matrix);
lower_triangular(matrix);

return 0;
}

#### Output

1   0   0   0
1   2   0   0
1   2   3   0
1   2   3   4

Yes
/*
C++ Program
Check if matrix is lower triangular
*/
#include<iostream>
#define ROW 4
#define COL 4
using namespace std;

class MyMatrix {
public:

//Display the element of given 2d matrix
void show_data(int matrix[][COL], int row, int col) {
for (int i = 0; i < row; ++i) {
for (int j = 0; j < col; ++j) {
cout << " " << matrix[i][j];
}
cout << "\n";
}
cout << "\n";
}
//Check if given matrix is lower triangular or not
void lower_triangular(int matrix[][COL], int row, int col) {
int status = 1;
for (int i = 0; i < col && status == 1; ++i) {
for (int j = i + 1; j < row && status == 1; ++j) {
if (matrix[i][j] != 0) {
//When matrix is not lower triangular
status = 0;
}
}
}
if (status == 1) {
cout << " Yes\n";
} else {
cout << " NO\n";
}
}
};
int main() {
MyMatrix obj ;
int matrix[][COL] = {
{
1,
0,
0,
0
},
{
1,
2,
0,
0
},
{
1,
2,
3,
0
},
{
1,
2,
3,
4
}
};
//This is size of matrix

obj.show_data(matrix, ROW, COL);
obj.lower_triangular(matrix, ROW, COL);
return 0;
}

#### Output

1 0 0 0
1 2 0 0
1 2 3 0
1 2 3 4

Yes
/*
Java Program
Check if matrix is lower triangular
*/
public class MyMatrix {

//Display the element of given 2d matrix
public void show_data(int [][]matrix, int row,int col) {

for (int i = 0; i < row; ++i) {

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

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

System.out.print("\n");
}

System.out.print("\n");
}
//Check if given matrix is lower triangular or not
public void lower_triangular(int [][]matrix, int row,int col)
{
int status=1;

for (int i = 0; i < col && status==1; ++i)
{
for (int j = i+1; j < row && status==1; ++j)
{
if(matrix[i][j] != 0)
{
//When matrix is not lower triangular
status=0;
}
}

}
if(status==1)
{
System.out.print("  Yes\n");
}
else
{
System.out.print("  NO\n");
}

}

public static void main(String[] args)
{

MyMatrix obj = new MyMatrix();
int [][]matrix =  {
{ 1, 0, 0, 0 },
{ 1, 2, 0, 0 },
{ 1, 2, 3, 0 },
{ 1, 2, 3, 4 }
};
//This is size of matrix
int row = matrix.length;
int col = matrix[0].length;

obj.show_data(matrix,row,col);
obj.lower_triangular(matrix,row,col);

}
}

#### Output

1 0 0 0
1 2 0 0
1 2 3 0
1 2 3 4

Yes
/*
C# Program
Check if matrix is lower triangular
*/
using System;

public class MyMatrix {
//Display the element of given 2d matrix
public void show_data(int[,] matrix, int row, int col) {
for (int i = 0; i < row; ++i) {
for (int j = 0; j < col; ++j) {
Console.Write(" " + matrix[i,j]);
}
Console.Write("\n");
}
Console.Write("\n");
}
//Check if given matrix is lower triangular or not
public void lower_triangular(int[,] matrix, int row, int col) {
int status = 1;
for (int i = 0; i < col && status == 1; ++i) {
for (int j = i + 1; j < row && status == 1; ++j) {
if (matrix[i,j] != 0) {
//When matrix is not lower triangular
status = 0;
}
}
}
if (status == 1) {
Console.Write(" Yes\n");
} else {
Console.Write(" NO\n");
}
}
public static void Main(String[] args) {
MyMatrix obj = new MyMatrix();
int[,] matrix = {
{
1,
0,
0,
0
},
{
1,
2,
0,
0
},
{
1,
2,
3,
0
},
{
1,
2,
3,
4
}
};
//This is size of matrix
int row = matrix.GetLength(0);
int col = matrix.GetLength(1);
obj.show_data(matrix, row, col);
obj.lower_triangular(matrix, row, col);
}
}

#### Output

1 0 0 0
1 2 0 0
1 2 3 0
1 2 3 4

Yes
<?php
/*
Php Program
Check if matrix is lower triangular
*/
class MyMatrix {
//Display the element of given 2d matrix
public 	function show_data(\$matrix, \$row, \$col) {
for (\$i = 0; \$i < \$row; ++\$i) {
for (\$j = 0; \$j < \$col; ++\$j) {
echo(" ". \$matrix[\$i][\$j]);
}
echo("\n");
}
echo("\n");
}
//Check if given matrix is lower triangular or not
public 	function lower_triangular(\$matrix, \$row, \$col) {
\$status = 1;
for (\$i = 0; \$i < \$col && \$status == 1; ++\$i) {
for (\$j = \$i + 1; \$j < \$row && \$status == 1; ++\$j) {
if (\$matrix[\$i][\$j] != 0) {
//When matrix is not lower triangular
\$status = 0;
}
}
}
if (\$status == 1) {
echo(" Yes\n");
} else {
echo(" NO\n");
}
}
};

function main() {
\$obj = new MyMatrix();
\$matrix = array(
array(1, 0, 0, 0),
array(1, 2, 0, 0),
array(1, 2, 3, 0),
array(1, 2, 3, 4)
);
//This is size of matrix
\$row = count(\$matrix);
\$col = count(\$matrix[0]);
\$obj->show_data(\$matrix, \$row, \$col);
\$obj->lower_triangular(\$matrix, \$row, \$col);

}
main();

#### Output

1 0 0 0
1 2 0 0
1 2 3 0
1 2 3 4

Yes
/*
Node Js Program
Check if matrix is lower triangular
*/
class MyMatrix {
//Display the element of given 2d matrix
show_data(matrix, row, col) {
for (var i = 0; i < row; ++i) {
for (var j = 0; j < col; ++j) {
process.stdout.write(" " + matrix[i][j]);
}

process.stdout.write("\n");
}

process.stdout.write("\n");
}

//Check if given matrix is lower triangular or not
lower_triangular(matrix, row, col) {
var status = 1;
for (var i = 0; i < col && status == 1; ++i) {
for (var j = i + 1; j < row && status == 1; ++j) {
if (matrix[i][j] != 0) {
//When matrix is not lower triangular
status = 0;
}
}
}

if (status == 1) {
process.stdout.write(" Yes\n");
} else {
process.stdout.write(" NO\n");
}
}
}

function main(args) {
var obj = new MyMatrix();
var matrix = [
[1, 0, 0, 0],
[1, 2, 0, 0],
[1, 2, 3, 0],
[1, 2, 3, 4]
];
//This is size of matrix
var row = matrix.length;
var col = matrix[0].length;
obj.show_data(matrix, row, col);
obj.lower_triangular(matrix, row, col);
}

main();

#### Output

1 0 0 0
1 2 0 0
1 2 3 0
1 2 3 4

Yes
#   Python 3 Program
#   Check if matrix is lower triangular
class MyMatrix :
# Display the element of given 2d matrix
def show_data(self, matrix, row, col) :
i = 0
while (i < row) :
j = 0
while (j < col) :
print(" ", matrix[i][j], end = "")
j += 1

print("\n", end = "")
i += 1

print("\n", end = "")

# Check if given matrix is lower triangular or not
def lower_triangular(self, matrix, row, col) :
status = 1
i = 0
while (i < col and status == 1) :
j = i + 1
while (j < row and status == 1) :
if (matrix[i][j] != 0) :
# When matrix is not lower triangular
status = 0

j += 1

i += 1

if (status == 1) :
print(" Yes\n", end = "")
else :
print(" NO\n", end = "")

def main() :
obj = MyMatrix()
matrix = [
[1, 0, 0, 0],
[1, 2, 0, 0],
[1, 2, 3, 0],
[1, 2, 3, 4]
]
row = len(matrix)
col = len(matrix[0])
obj.show_data(matrix, row, col)
obj.lower_triangular(matrix, row, col)

if __name__ == "__main__":
main()

#### Output

1  0  0  0
1  2  0  0
1  2  3  0
1  2  3  4

Yes
#   Ruby Program
#   Check if matrix is lower triangular
class MyMatrix
# Display the element of given 2d matrix
def show_data(matrix, row, col)
i = 0
while (i < row)
j = 0
while (j < col)
print(" ", matrix[i][j])
j += 1
end
print("\n")
i += 1
end
print("\n")
end
# Check if given matrix is lower triangular or not
def lower_triangular(matrix, row, col)
status = 1
i = 0
while (i < col && status == 1)
j = i + 1
while (j < row && status == 1)
if (matrix[i][j] != 0)
# When matrix is not lower triangular
status = 0
end
j += 1
end
i += 1
end
if (status == 1)
print(" Yes\n")
else
print(" NO\n")
end
end
end
def main()
obj = MyMatrix.new()
matrix = [
[1, 0, 0, 0],
[1, 2, 0, 0],
[1, 2, 3, 0],
[1, 2, 3, 4]
]
row = matrix.length
col = matrix[0].length
obj.show_data(matrix, row, col)
obj.lower_triangular(matrix, row, col)
end
main()

#### Output

1 0 0 0
1 2 0 0
1 2 3 0
1 2 3 4

Yes
/*
Scala Program
Check if matrix is lower triangular
*/
class MyMatrix {
//Display the element of given 2d matrix
def show_data(matrix: Array[Array[Int]], row: Int, col: Int): Unit = {
var i: Int = 0;
while (i < row) {
var j: Int = 0;
while (j < col) {
print(" " + matrix(i)(j));
j += 1;
}
print("\n");
i += 1;
}
print("\n");
}
//Check if given matrix is lower triangular or not
def lower_triangular(matrix: Array[Array[Int]], row: Int, col: Int): Unit = {
var status: Int = 1;
var i: Int = 0;
while (i < col && status == 1) {
var j: Int = i + 1;
while (j < row && status == 1) {
if (matrix(i)(j) != 0) {
//When matrix is not lower triangular
status = 0;
}
j += 1;
}
i += 1;
}
if (status == 1) {
print(" Yes\n");
} else {
print(" NO\n");
}
}
}
object Main {
def main(args: Array[String]): Unit = {
val obj: MyMatrix = new MyMatrix();
val matrix: Array[Array[Int]] = Array(
Array(1, 0, 0, 0),
Array(1, 2, 0, 0),
Array(1, 2, 3, 0),
Array(1, 2, 3, 4));
val row: Int = matrix.length;
val col: Int = matrix(0).length;
obj.show_data(matrix, row, col);
obj.lower_triangular(matrix, row, col);
}
}

#### Output

1 0 0 0
1 2 0 0
1 2 3 0
1 2 3 4

Yes
/*
Swift Program
Check if matrix is lower triangular
*/
class MyMatrix {
//Display the element of given 2d matrix
func show_data(_ matrix: [
[Int]
], _ row: Int, _ col: Int) {
var i: Int = 0;
while (i < row) {
var j: Int = 0;
while (j < col) {
print(" ", matrix[i][j], terminator: "");
j += 1;
}
print("\n", terminator: "");
i += 1;
}
print("\n", terminator: "");
}
//Check if given matrix is lower triangular or not
func lower_triangular(_ matrix: [
[Int]
], _ row: Int, _ col: Int) {
var status: Int = 1;
var i: Int = 0;
while (i < col && status == 1) {
var j: Int = i + 1;
while (j < row && status == 1) {
if (matrix[i][j] != 0) {
//When matrix is not lower triangular
status = 0;
}
j += 1;
}
i += 1;
}
if (status == 1) {
print(" Yes\n", terminator: "");
} else {
print(" NO\n", terminator: "");
}
}
}
func main() {
let obj: MyMatrix = MyMatrix();
let matrix: [
[Int]
] = [
[1, 0, 0, 0],
[1, 2, 0, 0],
[1, 2, 3, 0],
[1, 2, 3, 4]
];
let row: Int = matrix.count;
let col: Int = matrix[0].count;
obj.show_data(matrix, row, col);
obj.lower_triangular(matrix, row, col);
}
main();

1  0  0  0
1  2  0  0
1  2  3  0
1  2  3  4

Yes

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