/// <summary>
/// Main Streamflow Disaggregation script
/// Follows procedures laid out by UofI's A.Acharya and Dr.Ryu
/// We programmed a monthly-to-daily-disaggregation method in 2012 initially
/// based on some research by University of Idaho academics; the paper that the
/// program is based can be found in the links below. We've since made several
/// modifications to the program mainly to make it more robust in the sense that
/// it handles more cases that would have resulted in errors and to
/// make the mass-balancing more appropriate.
///
/// Published Journal Article - http://ascelibrary.org/doi/abs/10.1061/(ASCE)HE.1943-5584.0000818
///Article Manuscript - http://water.cals.uidaho.edu/publications/SimpleDisaggregation_Acharya_2013.pdf
/// </summary>
/// <param name="daily">daily series (cfs)</param>
/// <param name="monthly">monthly series (cfs or acre-feet)</param>
/// <returns></returns>
public static Series RMSEInterp(Series daily, Series monthly)
{
// Generates the monthly totals for the RMS calculations in cu.ft/month
Series SSmonthTot = MonthSum(Math.MonthlyAverage(daily));
Series TSmonthTot = MonthSum(ConvertAcreFeetToCfs(monthly));
// Builds a Series to keep track of the corresponding year with the minimum RMSe
Series TSrms = RMSEGenerateMatchList(SSmonthTot, TSmonthTot);
// New series for the estimated daily value
Series TSdaily = new Series();
// Loop to calculate the daily estimate
for (int i = 0; i < TSrms.Count; i++)
{
int targetYear = Convert.ToInt16(TSrms[i].Value);
int sourceYear = TSrms[i].DateTime.Year;
// Leap Years are fun! Catch leap/non-leap year mismatches.
// If the target is a leap year, this leaves 2-29 empty
DateTime tLookup;
if (TSrms[i].DateTime.Month == 2 && (DateTime.IsLeapYear(targetYear) ^ DateTime.IsLeapYear(sourceYear)))
{
tLookup = new DateTime(targetYear, TSrms[i].DateTime.Month, 28);
}
else
{
tLookup = new DateTime(targetYear, TSrms[i].DateTime.Month, TSrms[i].DateTime.Day);
}
// Calculates daily ratio of the monthly total for the SS
double SSmatchMonthly = SSmonthTot.Lookup(tLookup);
DateTime tStart = new DateTime(targetYear, TSrms[i].DateTime.Month, 1);
Series SSmatchDaily = TimeSeries.Math.FillMissingWithZero(daily.Subset(tStart, tLookup));
Series SSratioTemp = SSmatchDaily / SSmatchMonthly;
// Catches NaN values if the SS monthly data is zero and leap day mass balance problems
Series SSratio = new Series();
double leapDayRatio = 0.0;
for (int x = 0; x < SSratioTemp.Count; x++)
{
Point ptX = SSratioTemp[x];
if (ptX.Value.ToString() == "NaN" || SSmatchMonthly == 0.0)
{
SSratio.Add(ptX.DateTime, 0.0);
continue;
}
// Catches TS leap years and ensures that mass balance is preserved with Feb-29th
if (DateTime.IsLeapYear(sourceYear) && !DateTime.IsLeapYear(targetYear) &&
SSratio.MinDateTime.Month == 2)
{
leapDayRatio = leapDayRatio + (ptX.Value / 28.0);
SSratio.Add(ptX.DateTime, ptX.Value - (ptX.Value / 28.0));
}
else if (!DateTime.IsLeapYear(sourceYear) && DateTime.IsLeapYear(targetYear) &&
SSratio.MinDateTime.Month == 2)
{
leapDayRatio = daily[new DateTime(SSratioTemp.MaxDateTime.Year, 2, 29)].Value / SSmatchMonthly;
SSratio.Add(ptX.DateTime, ptX.Value + (leapDayRatio / 27.0));
}
else
{
SSratio.Add(ptX);
}
}
// Calculates the estimated daily for the TS given the monthly total and SS ratio
TSdaily = RMSEGenerateDaily(TSdaily, TSmonthTot.Lookup(TSrms[i].DateTime.Date), SSmatchDaily, SSratio,
targetYear, sourceYear, leapDayRatio);
}
return(TSdaily);
}