/**++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 *
 *                                              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:       math
 * File Name:         dot.hpp
 * Revision:          0.1.0
 * Date:              31-07-2026
 * Author:            Michelle Bausager
 *
 * Description:
 * Functions to calculate dot product of tensors;
 *
 *++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++*/
#pragma once
//---------------------------------------------------------------------------------------------------------------------------
// INCLUDE DESCRIPTION
//-----------------------------------------------------------------------------------------------------

#include <tensor/vector.hpp>
#include <tensor/matrix.hpp> // for panic::real_matrix

namespace panic{
namespace math{

/**
 * @brief Returns dor product of vector and vector.
 *
 * Computes:
 * @code
 * @endcode
 *
 * @tparam T Numeric element type.
 * @param a First vector.
 * @param b Second vector for dot product. Need to be @p a.size()
 *
 */
template <typename T>
T dot(const panic::tensor::vector<T>& a, const panic::tensor::vector<T>& b);

/**
 * @brief Returns a new vector of dot product of a matrix and vector.
 *
 * Computes:
 * @code
 * @endcode
 *
 * @tparam T Numeric element type.
 * @param A Input matrix.
 * @param b Input vector. @ p b.size needs to be the size of @p A.cols.
 * @param c Output vector with result.
 *
 * @return true if success
 * @return false if resizeing fails or dimention mismatch
 *
 */
template <typename T>
bool dot(const panic::tensor::matrix<T>& A, const panic::tensor::matrix<T>& b, panic::tensor::vector<T>& c);


/**
 * @brief Returns a new vector of dot product of a matrix and vector.
 *
 * Computes:
 * @code
 * @endcode
 *
 * @tparam T Numeric element type.
 * @param A Input matrix.
 * @param b Input vector. @ p b.size needs to be the size of @p A.cols.
 *
 * @return A new matrix containing the result.
 * @return An empty vector if the operation fails.
 *
 * @note This overload is convenient, but may allocate a new matrix.
 */
template <typename T>
panic::tensor::vector<T> dot(const panic::tensor::matrix<T>& A, const panic::tensor::matrix<T>& b);



} // namespace math
} // namespace panic