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As described in detail below 3.4 (see also [2]) the list of calibration datasets comprising a CIF is ruled by two dates: the observation date and the analysis date.
By default cifbuild reads the observation date from the Observation Data File (ODF) pointed to via the SAS_ODF environment variable.
If an ODF is not available the observation date can be specified with the parameters withobservationdate and observationdate.
The analysis date is given with the parameter analysisdate, and it defaults to now. Note that the analysis date can be any date (in the past or in the future): it is used to retrieve the CCF constituents applicable at the specified point in time.
For instance, to generate the CIF applicable on 2010-01-01 say analysisdate=2010-01-01. What CCF constituents would one have used on 2005-01-01? Use analysisdate=2005-01-01.
The analysis and observation dates used in the creation of the CIF are recorded in the two block attributes OBSVDATE and ANALDATE respectively. (See 7.)
Note that it is possible to use an analysis date earlier than the observation date. This is flagged with a warning, and may lead to an inconsistent calibration.