/// <summary>
/// Invokes a delegate when the value of the element of the matrix changed.
/// </summary>
/// <param name="e">Arguments of event.</param>
/// <exception cref="ArgumentNullException">
/// Thrown when <see cref="Matrix{T}.ValueChanged"/> equal to null.
/// </exception>
protected virtual void OnChange(MatrixEventArgs <T> e)
{
if (ReferenceEquals(ValueChanged, null))
{
throw new ArgumentNullException(nameof(ValueChanged));
}
ValueChanged(this, e);
}
/// <summary>
/// The indexer for the <see cref="SquareMatrix{T}"/>.
/// </summary>
/// <param name="indexI">The row number.</param>
/// <param name="indexJ">The column number.</param>
/// <exception cref="ArgumentOutOfRangeException">
/// Thrown when <paramref name="indexI"/> or/and <paramref name="indexJ"/> less than 0 or
/// greater than or equal to the order of matrix.
/// </exception>
/// <returns>The element of matrix on passed indexes.</returns>
public virtual T this[int indexI, int indexJ]
{
get
{
if ((indexI < 0) || (indexI >= _order))
{
throw new ArgumentOutOfRangeException("Index i of the matrix element must be greater than 0 and less than order.", nameof(indexI));
}
if ((indexJ < 0) || (indexJ >= _order))
{
throw new ArgumentOutOfRangeException("Index j of the matrix element must be greater than 0 and less than order.", nameof(indexI));
}
return(_matrix[indexI, indexJ]);
}
set
{
if ((indexI < 0) || (indexI >= _order))
{
throw new ArgumentOutOfRangeException("Index i of the matrix element must be greater than 0 and less than order.", nameof(indexI));
}
if ((indexJ < 0) || (indexJ >= _order))
{
throw new ArgumentOutOfRangeException("Index j of the matrix element must be greater than 0 and less than order.", nameof(indexI));
}
MatrixEventArgs <T> eventArgs = new MatrixEventArgs <T>()
{
I = indexI,
J = indexJ,
OldValue = _matrix[indexI, indexJ],
NewValue = value
};
_matrix[indexI, indexJ] = value;
OnChange(eventArgs);
}
}