panic/include/tensor/matrix.hpp

/**++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 *
 *                                              PANIC
 *                              Portable Algorithms and Numerics In C++
 *
 *                       Scientific computing from scratch, with feeling.
 *
 * Copyright (c) 2026 Michelle Bausager
 *
 * This file is part of PANIC.
 *
 * PANIC is free software licensed under the GNU General Public License v3.0 or later.
 * You may redistribute and/or modify it under the terms of the GPL.
 *
 * PANIC is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
 * without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 * See the LICENSE file for the full license text.
 *
 * SPDX-License-Identifier: GPL-3.0-or-later
 *
 *++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 *
 * Project Name:      PANIC
 * Module Name:       tensor
 * File Name:         matrix.hpp
 * Revision:          0.1.0
 * Date:              23-06-2026
 * Author:            Michelle Bausager
 *
 * Description:
 * Defines the matrix object that will be used in the rest of the libraries.
 *
 *++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++*/
#pragma once
//---------------------------------------------------------------------------------------------------------------------------
// INCLUDE DESCRIPTION
//---------------------------------------------------------------------------------------------------------------------------
#include <config/types.hpp> // panic::uint_t, panic::int_t, and panic::real_t


namespace panic{
	namespace tensor{

/**
 * @brief struct for matrix object
 *
 * The struct is used for all PANIC libraries
 * It uses dynamic allocation with new[] nad delete[].
 * Copying performs a deep copy.
 */
template <typename T>
struct matrix{
	// Variable for number of rows
	panic::types::uint_t n;
	// Variable for number of cols
	panic::types::uint_t m;
	// Variable for length of data array
	panic::types::uint_t length;
	// Pointer to data array
	T* data;

    /**
     * @brief Empthy constructor
     *
     */
	matrix();

    /**
     * @brief Contructor with size allocation.
     *
     * @param rows Number of rows in the matrix
     * @param cols Number of columns in the matrix
     */
	matrix(panic::types::uint_t rows, panic::types::uint_t cols);

    /**
     * @brief Contructor with size allocation and sets it all to a value.
     *
     * @param rows Number of rows in the matrix
     * @param cols Number of columns in the matrix
     * @param value all the values in the matrix.
     */
	matrix(panic::types::uint_t rows, panic::types::uint_t cols, T value);

	/**
	 * @brief Copy-contructor.
	 *
	 * Computes:
	 * @code
	 * matrix A(3,3);
	 * matrix B = A;
	 * @endcode
	 *
	 */
	matrix(const matrix& other);

	/**
	 * @brief De-contructor, releases memory.
	 *
	 * @note Releases memory.
	 */
	~matrix();

	/**
	 * @brief Copy-assignment.
	 *
	 * Computes:
	 * @code
	 * matrix A(3,3);
	 * matrix B(5,8);
	 * B = A;
	 * @endcode
	 *
	 */
	matrix& operator=(const matrix& other);

	/**
	 * @brief Returns number of rows.
	 *
	 * Computes:
	 * @code
	 * n = A.rows();
	 * @endcode
	 * 
	 * @note The const tells compiler that the fuction don't edit the objert.
	 */
	panic::types::uint_t rows() const;

	/**
	 * @brief Returns number of columns.
	 *
	 * Computes:
	 * @code
	 * m = A.cols();
	 * @endcode
	 * 
	 * @note The const tells compiler that the fuction don't edit the objert.
	 */
	panic::types::uint_t cols() const;
	
	/**
	 * @brief Function to resize data matrix.
	 *
	 * Computes:
	 * @code
	 * A.resize(3,4);
	 * @endcode
	 * 
	 * @note It hold all the privious functions if avaliable.
	 */
	bool resize(panic::types::uint_t new_n, panic::types::uint_t new_m);

	/**
	 * @brief Fill data with value.
	 *
	 * Computes:
	 * @code
	 * A.fill(3.1415);
	 * @endcode
	 * 
	 * @note Sets all values in the matrix.
	 */
	bool fill(T value);

	/**
	 * @brief Read and write matrix data using row and column
	 *
	 * Computes:
	 * @code
	 * n = A(1,2);
	 * @endcode
	 * 
	 * @note This is unchecked and fast.
	 */
    T& operator()(panic::types::uint_t index_n, panic::types::uint_t index_m);


	/**
	 * @brief Read from const matrix data using row and column
	 *
	 * Computes:
	 * @code
	 * n = const A(1,2);
	 * @endcode
	 * 
	 * @note This is unchecked and fast.
	 */
    const T& operator()(panic::types::uint_t index_n, panic::types::uint_t index_m) const;

};


//---------------------------------------------------------------------------------------------------------------------------
// TYPE ALIASES
//---------------------------------------------------------------------------------------------------------------------------

typedef matrix<panic::types::real_t> real_matrix;
typedef matrix<panic::types::int_t>  int_matrix;
typedef matrix<panic::types::uint_t> uint_matrix;

//---------------------------------------------------------------------------------------------------------------------------
// EXPLICIT TEMPLATE DECLARATION
//---------------------------------------------------------------------------------------------------------------------------

extern template struct matrix<panic::types::real_t>;
extern template struct matrix<panic::types::int_t>;
extern template struct matrix<panic::types::uint_t>;


	} // namespace tensor
} // namespace panic