/// <summary>
/// Returns a set of linear weights along with timeSegmint for with dataIndeces in linear weights are valid
/// </summary>
/// <param name="context"></param>
/// <param name="computationalContext"></param>
/// <param name="cells"></param>
/// <returns></returns>
protected IEnumerable <Tuple <ITimeSegment, LinearWeight[]> > CalcLinearWeights(ComputationalContext computationalContext, IEnumerable <GeoCellTuple> cells)
{
if (!computationalContext.ContainsKey("observations"))
{
throw new InvalidOperationException("Call SaveObservationsAndDalanayDiagsForCells prior calling CompleteAggregateCellsBatch");
}
ISpatPointsLinearInterpolator2D spli2d = (ISpatPointsLinearInterpolator2D)spatialIntegrator;
Dictionary <ITimeSegment, IObservationsInformation> observations = (Dictionary <ITimeSegment, IObservationsInformation>)computationalContext["observations"];
Dictionary <ITimeSegment, object> delanays = (Dictionary <ITimeSegment, object>)computationalContext["dalanays"];
var sw1 = System.Diagnostics.Stopwatch.StartNew();
TraceVerbose("Computing field values");
//WARNING: can't be paralleled as dalanays are not thread safe
foreach (var cell in cells)
{
var timeSegment = cell.Time;
var observation = observations[timeSegment].Observations;
object delanay = delanays[timeSegment];
double latmax = cell.LatMax, latmin = cell.LatMin, lonmax = cell.LonMax, lonmin = cell.LonMin;
if (latmax == latmin && lonmax == lonmin)
{
yield return(Tuple.Create(timeSegment, spli2d.GetLinearWeigths(latmin, lonmin, delanay)));
}
else
{
var sizeSqrt = (int)Math.Sqrt(cellAveragingGridSize);
LinearWeight[][] toFlatten = new LinearWeight[sizeSqrt * sizeSqrt][];
double latStep = (latmax - latmin) / (sizeSqrt - 1);
double lonStep = (lonmax - lonmin) / (sizeSqrt - 1);
for (int i = 0; i < sizeSqrt; i++)
{
for (int j = 0; j < sizeSqrt; j++)
{
var w = spli2d.GetLinearWeigths(latmin + latStep * i, lonmin + lonStep * j, delanay);
toFlatten[sizeSqrt * i + j] = w;
}
}
var devisor = sizeSqrt * sizeSqrt;
var flattenedWeights = toFlatten.SelectMany(weights => weights).GroupBy(w => w.DataIndex).Select(g => new LinearWeight(g.Key, g.Select(g1 => g1.Weight).Sum() / devisor)).ToArray();
yield return(Tuple.Create(timeSegment, flattenedWeights));
}
}
TraceVerbose("Computing field values finished in {0}", sw1.Elapsed);
}