KEEPEVENT Statement
- KEEPEVENT variable-list;
The KEEPEVENT statement specifies which event
variables in the data file are to be included in
the OUTEVENT= data set. As a result, the KEEPEVENT statement
is valid only for data files containing
event-oriented time series data, that is, only for CRSP files.
All the BY variables, the time ID variable DATE and
the event-grouping variable EVENT are always
included in the OUTEVENT= data set.
These variables can not be referenced in the KEEPEVENT statement.
If any of these variables are referenced, a warning message is
given and the reference is ignored.
The variable list can contain variable names
or name range specifications.
See the section "Variable Lists" for details.
Only one KEEPEVENT or one DROPEVENT statement can be used.
KEEPEVENT and DROPEVENT are mutually exclusive.
You can also use the KEEP= data set option
to control which event variables to include in the OUTEVENT= data set.
However, the KEEPEVENT statement differs from the
KEEP= data set option in several aspects:
- The KEEPEVENT statement selection is applied
before variables are read from the data file,
while the KEEP= data set option selection is applied
after variables are read and as they are written
to the OUTEVENT= data set.
Therefore, using the KEEPEVENT statement instead of
the KEEP= data set option is much more efficient.
- If the KEEPEVENT statement causes no event variables
to be selected, then no observations are output
to the OUTEVENT= data set.
Copyright © 1999 by SAS Institute Inc., Cary, NC, USA. All rights reserved.
