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Kotlin program to check Identity Matrix

Kotlin | Identity Matrix: Here, we are going to learn how to check whether a given matrix is identity matrix or not in Kotlin programming language? Submitted by IncludeHelp, on May 06, 2020

Kotlin - Check Identity Matrix

An identity Matrix is a square matrix in which all the elements of the principal diagonal are ones and all other elements are zeros.

Given a matrix, we have to check whether it is identity matrix or not.

Example

Input:
matrix:
[1, 0, 0]
[0, 1, 0]
[0, 0, 1]

Output:
Identity Matrix !!

Program to check Identity Matrix in Kotlin

package com.includehelp

import java.util.*

// Main function, Entry Point of Program
fun main(args: Array<String>) {

    //variable of rows and col
    val rows: Int
    val column: Int

    var isIdentityMatrix: Boolean=true

    //Input Stream
    val scanner = Scanner(System.`in`)

    //Input no of rows and column
    print("Enter the number of rows and columns of matrix : ")
    rows   = scanner.nextInt()
    column = scanner.nextInt()

    if(rows!=column) {
        println("Matrix should be Square matrix , Rows and Col size must be Same !!")
        return
    }

    //Create Array
    val matrixA     = Array(rows) { IntArray(column) }

    //Input Matrix
    println("Enter the Elements of First Matrix ($rows X $column} ): ")
    for(i in matrixA.indices){
        for(j in matrixA[i].indices){
            print("matrixA[$i][$j]: ")
            matrixA[i][j]=scanner.nextInt()
        }
    }

    //print Matrix A
    println("Matrix A : ")
    for(i in matrixA.indices){
        println("${matrixA[i].contentToString()} ")
    }

    //Determine Identity Matrix
    for(i in matrixA.indices){
        for(j in matrixA[i].indices){

            if(i==j && matrixA[i][j]!=1){
                isIdentityMatrix=false
                break
            }
            else if(i!=j && matrixA[i][j]!=0){
                isIdentityMatrix=false
                break
            }
        }
    }

    if(isIdentityMatrix) println("Identity Matrix !! ") else println("Not a Identity Matrix !!")
}

Output

Run 1:
Enter the number of rows and columns of matrix : 4
3
Matrix should be Square matrix , Rows and Col size must be Same
---
Run 2:
Enter the number of rows and columns of matrix : 3
3
Enter the Elements of First Matrix (3 X 3} ):
matrixA[0][0]: 1
matrixA[0][1]: 0
matrixA[0][2]: 0
matrixA[1][0]: 0
matrixA[1][1]: 1
matrixA[1][2]: 0
matrixA[2][0]: 0
matrixA[2][1]: 0
matrixA[2][2]: 1
Matrix A :
[1, 0, 0]
[0, 1, 0]
[0, 0, 1]
Identity Matrix !!
--------
Run 3:
Enter the number of rows and columns of matrix : 2
2
Enter the Elements of First Matrix (2 X 2} ):
matrixA[0][0]: 1
matrixA[0][1]: 5
matrixA[1][0]: 3
matrixA[1][1]: 0
Matrix A :
[1, 5]
[3, 0]
Not a Identity Matrix !!