/// <summary>
/// Adds the <see cref="SymmetricalMatrix{T}"/> and the <see cref="SquareMatrix{T}"/>.
/// </summary>
/// <typeparam name="T">Type of matrices elements.</typeparam>
/// <param name="firstMatrix">The first matrix to add.</param>
/// <param name="secondMatrix">The second matrix to add.</param>
/// <returns>The matrix of added matrices elements.</returns>
public static SymmetricalMatrix <T> Add <T>(this SymmetricalMatrix <T> firstMatrix, SquareMatrix <T> secondMatrix) => Add(secondMatrix, firstMatrix);
/// <summary>
/// Adds the <see cref="SquareMatrix{T}"/> and the <see cref="DiagonalMatrix{T}"/>.
/// </summary>
/// <typeparam name="T">Type of matrices elements.</typeparam>
/// <param name="firstMatrix">The first matrix to add.</param>
/// <param name="secondMatrix">The second matrix to add.</param>
/// <returns>The matrix of added matrices elements.</returns>
public static SquareMatrix <T> Add <T>(this SquareMatrix <T> firstMatrix, DiagonalMatrix <T> secondMatrix)
{
return(new SquareMatrix <T>(AddMatrix <T>(firstMatrix, secondMatrix)));
}
/// <summary>
/// Adds the <see cref="DiagonalMatrix{T}"/> and the <see cref="SquareMatrix{T}"/>.
/// </summary>
/// <typeparam name="T">Type of matrices elements.</typeparam>
/// <param name="firstMatrix">The first matrix to add.</param>
/// <param name="secondMatrix">The second matrix to add.</param>
/// <returns>The matrix of added matrices elements.</returns>
public static SquareMatrix <T> Add <T>(this DiagonalMatrix <T> firstMatrix, SquareMatrix <T> secondMatrix) => Add(secondMatrix, firstMatrix);