Matrix

Matrix is a single-header C++ matrix library that offers a clean interface for working with matrices in your applications. Notably, this library comes with LAPACK support to provide efficient linear algebra operations, all within a single header file for your convenience.

Usage

Including the Header

To use the Matrix class in your C++ project, simply include the single header file:

#include "matrix.h"

If you want to enable BLAS and LAPACK support, you can use the following command after installing LAPACK:

make blas=1

Creating Matrices

Creating a matrix is straightforward:

Matrix<int, 2, 3> matrix;  // Creates a 2x3 matrix of integers, initialized to 0.

You can initialize matrices with data using initializer lists:

Matrix<double, 2, 2> matrix = {1.0, 2.0, 3.0, 4.0};

Basic Operations

Perform basic operations like addition, subtraction, unary minus, multiplication and inversion:

Matrix<double, 2, 2> sum = matrix1 + matrix2;       // Matrix addition
Matrix<double, 2, 2> diff = matrix2 - matrix1;      // Matrix subtraction
Matrix<double, 2, 2> negated = -matrix1;            // Unary minus
Matrix<double, 2, 2> scaled = matrix1 * 2;          // Scalar multiplication
Matrix<double, 2, 2> product = matrix1 * matrix2;   // Matrix multiplication
Matrix<double, 2, 2> inverse = matrix1.inv();       // Matrix inversion
Matrix<double, 2, 2> transposed = matrix1.t()       // Matrix Transposition

Accessing Elements

Access matrix elements using parentheses or data() for const objects:

double element = matrix(0, 1);  // Accesses the element at row 0, column 1
const double* dataPtr = matrix.data();
double thirdElement = dataPtr[2];  // Accesses the third element

Printing Matrices

Print matrices neatly using the overloaded << operator:

std::cout << "Matrix:\n" << matrix << std::endl;