/// <summary>
/// Initializes a new instance of the <see cref="FixedEulerStateDerivative"/> class.
/// </summary>
/// <param name="method">The method.</param>
public FixedEulerStateDerivative(FixedEuler method)
{
_method = method.ThrowIfNull(nameof(method));
_index = method.StateManager.AllocateState(1);
_states = method.IntegrationStates;
}
/// <summary>
/// Initializes a new instance of the <see cref="FixedEulerStateDerivative"/> class.
/// </summary>
/// <param name="method">The method.</param>
public FixedEulerStateDerivative(FixedEuler method)
{
_method = method;
_index = method.StateManager.AllocateState(1);
_states = method.IntegrationStates;
}