private static INullableQueryTable <T> TempMath <T>(INullableQueryTable <T> sourceTable, string temperatureName,
string humidityName, string dewPointName, Func <TemperatureMath, double> valueSelector) where T : struct
{
return(sourceTable.ToNewTable((o, n) =>
{
n.AddSerie(sourceTable.TryGetSerie(temperatureName)
.Zip(sourceTable.TryGetSerie(humidityName), dewPointName,
(t, h) =>
{
if (!t.HasValue || !h.HasValue)
{
return null;
}
var tempMath = new TemperatureMath(Convert.ToDouble(t.Value), Convert.ToDouble(h.Value));
return (T)Convert.ChangeType(valueSelector(tempMath), typeof(T));
}));
}));
}
private static INullableQueryTable <T> CalcLine <T>(INullableQueryTable <T> sourceTable, string temperatureName,
string humidityName, string resultName, float dewPoint, float stationAltitude) where T : struct
{
return(sourceTable.ToNewTable((o, n) =>
{
n.AddSerie(sourceTable.TryGetSerie(temperatureName)
.Zip(sourceTable.TryGetSerie(humidityName), resultName,
(t, h) =>
{
if (t.HasValue == false || h.HasValue == false)
{
return null;
}
T?snowTemp = CalcSnowingTemperature(dewPoint, h);
var altititude = stationAltitude + (t.ToFloat() - snowTemp.ToFloat()) * 160;
return altititude.ToType <T>();
}));
}));
}
/// <summary>
/// Calculates the current temperature where percipitation will fall as snow
/// </summary>
/// <typeparam name="T"></typeparam>
/// <param name="sourceTable"></param>
/// <param name="humidityName"></param>
/// <param name="resultName"></param>
/// <param name="dewPoint">0°C for snow, 0.8°C for sleet</param>
/// <returns></returns>
public static INullableQueryTable <T> SnowingTemperature <T>(this INullableQueryTable <T> sourceTable,
string humidityName, string resultName = "Snowing Temperature", float dewPoint = 0.8f) where T : struct
{
return
(sourceTable.ToNewTable(
(o, n) =>
{
n.AddSerie(
sourceTable.TryGetSerie(humidityName)
.CalcValue(humidity => CalcSnowingTemperature(dewPoint, humidity), resultName));
}));
}