/// <summary>
/// Calculate the passband in the range of ndB dropped from the loss of specified wavelength
/// </summary>
/// <param name="CentralWavelength">The wavelength of the reference point</param>
/// <param name="DropdB"></param>
/// <returns>
/// Tuple.
/// item1: point on the left side of ITU
/// item2: point on the right side of ITU
/// item3: passband
/// </returns>
Tuple <Point, Point, double> CalPassBand(double CentralWavelength, double DropdB)
{
// get the point adjacents to the ITU
var pointRef = FindPointByWavelength(CentralWavelength);
// the IL used to calculate passband
var targeIL = pointRef.Y + DropdB;
// get the points before the ITU
var pointsBeforeITU = InsertionLoss.Reverse().SkipWhile(p => p.X > pointRef.X);
// get the point locates at the left side of the ITU
var pointLeftITU = pointsBeforeITU.SkipWhile(p => p.Y < targeIL).First();
// get the points after the ITU
var pointsAfterITU = InsertionLoss.SkipWhile(p => p.X < pointRef.X);
// get the point locates at the right side of the ITU
var pointRightITU = pointsAfterITU.Reverse().SkipWhile(p => p.Y > targeIL).First();
return(new Tuple <Point, Point, double>(pointLeftITU, pointRightITU, pointRightITU.X - pointLeftITU.X));
}
Point FindPointByWavelength(double Wavelength)
{
return(InsertionLoss.SkipWhile(a => a.X < Wavelength).ElementAt(0));
}
