C#: Create a identity matrix

C# Sharp Basic: Exercise-102 with Solution

In linear algebra, the identity matrix of size n is the n x n square matrix with ones on the main diagonal and zeros elsewhere.

Terminology and notation:

The identity matrix is often denoted by I_n, or simply by I if the size is immaterial or can be trivially determined by the context.

Write a C# Sharp program to create an identity matrix.

Sample Data:
Input a number: 3
1 0 0
0 1 0
0 0 1

Sample Solution:

C# Sharp Code:

using System;
using System.Linq;

namespace exercises
{
    class Program
    {
        static void Main(string[] args)
        {
            int n;

            // Prompt the user to input a number
            Console.WriteLine("Input a number:");

            // Read the input from the user and convert it to an integer
            n = Convert.ToInt32(Console.ReadLine());

            // Create a square matrix of size n x n filled with zeroes except for diagonal elements (identity matrix)
            var M =
                Enumerable.Range(0, n)
                    .Select(i =>
                        Enumerable.Repeat(0, n)
                            .Select((z, j) => j == i ? 1 : 0) // Sets diagonal elements to 1, rest to 0
                            .ToList()
                    )
                    .ToList();

            // Display the matrix (identity matrix) generated above
            foreach (var row in M)
            {
                foreach (var element in row)
                {
                    Console.Write(" " + element); // Print each element of the matrix row
                }
                Console.WriteLine(); // Move to the next line after printing each row
            }
        }
    }
}

Sample Output:

Input a number: 3
 1 0 0
 0 1 0
 0 0 1

Flowchart:

C# Sharp Code Editor:

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