/***************************************

*Name: Zachary Marcoux

*Date: 10/26/23

Class Period : 4th

*Project Name: Basic Matrix/Vector Calculator

*Project Description: Allows for basic matrix/vector operations to be performed. 

***************************************/

using System;

​

class Program

{

    static void Main()

    {

        bool exit = false;

        while (!exit)

        {

            Console.WriteLine("Please select an operation:");

            Console.WriteLine("1. Dot product between two 3x1 vectors");

            Console.WriteLine("2. Calculate cross product between two 3x1 vectors");

            Console.WriteLine("3. Calculate trace of a matrix (2x2 or 3x3)");

            Console.WriteLine("4. Calculate transpose of a matrix");

            Console.WriteLine("5. Exit");

            Console.Write("Enter your choice: ");

            int choice = int.Parse(Console.ReadLine());

​

            if (choice == 1)

            {

                double[] vector1 = ReadVector(3);

                double[] vector2 = ReadVector(3);

                double dotProduct = CalculateDotProduct(ref vector1, ref vector2);

                Console.WriteLine($"Dot Product: {dotProduct}");

            }

            else if (choice == 2)

            {

                double[] vectorA = ReadVector(3);

                double[] vectorB = ReadVector(3);

                double[] crossProduct = CalculateCrossProduct(ref vectorA, ref vectorB);

                Console.WriteLine($"Cross Product: [{crossProduct[0]}, {crossProduct[1]}, {crossProduct[2]}]");

            }

            else if (choice == 3)

            {

                Console.Write("Enter square matrix size (ex: [2] for 2x2 matrix): ");

                int size = int.Parse(Console.ReadLine());

                double[,] matrix = ReadMatrix(size);

                double trace = CalculateTrace(matrix);

                Console.WriteLine($"Trace: {trace}");

            }

            else if (choice == 4)

            {

                double[,] inputMatrix = ReadMatrix();

                double[,] transposeMatrix = CalculateTranspose(inputMatrix);

                Console.WriteLine("Transposed Matrix:");

                PrintMatrix(transposeMatrix);

            }

            else if (choice == 5)

            {

                exit = true;

            }

            else

            {

                Console.WriteLine("Invalid choice. Please try again.");

            }

        }

    }

​

    static double[] ReadVector(int size)

    {

        double[] vector = new double[size];

        Console.WriteLine($"Enter {size} elements for the vector:");

        for (int i = 0; i < size; i++)

        {

            Console.Write($"Element {i}: ");

            vector[i] = double.Parse(Console.ReadLine());

        }

        return vector;

    }

​

    static double[,] ReadMatrix(int size = 3)

    {

        double[,] matrix = new double[size, size];

        Console.WriteLine($"Enter {size}x{size} matrix elements:");

        for (int i = 0; i < size; i++)

        {

            for (int j = 0; j < size; j++)

            {

                Console.Write($"Element [{i},{j}]: ");

                matrix[i, j] = double.Parse(Console.ReadLine());

            }

        }

        return matrix;

    }

​

    static double CalculateDotProduct(ref double[] vector1, ref double[] vector2)

    {

        double result = 0;

        for (int i = 0; i < vector1.Length; i++)

        {

            result += vector1[i] * vector2[i];

        }

        return result;

    }

​

    static double[] CalculateCrossProduct(ref double[] vectorA, ref double[] vectorB)

    {

        double[] crossProduct = new double[3];

        crossProduct[0] = vectorA[1] * vectorB[2] - vectorA[2] * vectorB[1];

        crossProduct[1] = vectorA[2] * vectorB[0] - vectorA[0] * vectorB[2];

        crossProduct[2] = vectorA[0] * vectorB[1] - vectorA[1] * vectorB[0];

        return crossProduct;

    }

​

    static double CalculateTrace(double[,] matrix)

    {

        double trace = 0;

        for (int i = 0; i < matrix.GetLength(0); i++)

        {

            trace += matrix[i, i];

        }

        return trace;

    }

​

    static double[,] CalculateTranspose(double[,] matrix)

    {

        int rows = matrix.GetLength(0);

        int columns = matrix.GetLength(1);

        double[,] transposeMatrix = new double[columns, rows];

        for (int i = 0; i < columns; i++)

        {

            for (int j = 0; j < rows; j++)

            {

                transposeMatrix[i, j] = matrix[j, i];

            }

        }

        return transposeMatrix;

    }

​

    static void PrintMatrix(double[,] matrix)

    {

        int rows = matrix.GetLength(0);

        int columns = matrix.GetLength(1);

        for (int i = 0; i < rows; i++)

        {

            for (int j = 0; j < columns; j++)

            {

                Console.Write(matrix[i, j] + "      ");

            }

            Console.WriteLine();

        }

    }

}

​

​