/// <summary>
/// Returns the scale with the given criteria.
/// </summary>
/// <param name="key">Musical key.</param>
/// <param name="scale">Musical scale.</param>
/// <param name="inst">Melodic instrument.</param>
public Scale GetScale(Key key, ScaleInfo scale,
MelodicInstrument inst)
{
return(_scales[key][scale][inst]);
}