/// <summary>
/// Returns the consumption of a given kind of Mengeneinheit within the specified reference time range.
/// </summary>
/// <param name="em">Energiemenge</param>
/// <param name="reference">reference time frame</param>
/// <param name="wev">Wertermittlungsverfahren</param>
/// <param name="obiskennzahl">OBIS number</param>
/// <param name="me">an extensive unit (e.g. "kWh")</param>
/// <returns>the consumption within the give time slice <paramref name="reference"/> in the unit passed as <paramref name="me"/></returns>
public static decimal GetConsumption(this BO4E.BO.Energiemenge em, ITimeRange reference,
Wertermittlungsverfahren wev, string obiskennzahl, Mengeneinheit me)
{
if (!me.IsExtensive())
{
throw new ArgumentException($"The Mengeneinheit {me} isn't extensive. Calculating a consumption doesn't make sense.");
}
return(em.Energieverbrauch
.Where(v => v.Wertermittlungsverfahren == wev && v.Obiskennzahl == obiskennzahl && v.Einheit == me)
//.AsParallel<Verbrauch>()
.Sum(v => GetOverlapFactor(new TimeRange(v.Startdatum, v.Enddatum), reference, false) * v.Wert));
}
