RAnEn::toForecastTime converts the observation time index to forecast time index.
toForecastTime(observation.time.id, mapping, flt = NULL)The observation time index(es) from the Time column of the analogs member in
in the results of generateAnalogs.default.
The mapping table created from generateTimeMapping.
The lead time index.
This function does the following conversion.
Observation time index [ + Forecast lead time index ] ----> Forecast time index
To pin down the exact time of a forecast, two things are needed: forecast time and the lead time; to pin down the exact time of an observation, only the observation time is needed. Therefore, this function is devoted to convert from observation times to forecast times. Please note that, an observation time CAN be associated with multiple forecast times because of the existence of forecast lead times. If you have constraints on the lead time, then the match between forecasts and observations becomes one-on-one.
The observation time index usually comes from the Time column of the analogs member in the results of
generateAnalogs.default. This time is observation times. However, please note that the times in the
similarity member are forecast times. These two are different.