You can specify a BY statement with PROC PLS to obtain separate
analyses on observations in groups defined by the BY variables. When a
BY statement appears, the procedure expects the input data set to be
sorted in order of the BY variables. The variables are one or
more variables in the input data set.
- BY variables ;
If you specify more than one BY statement, the procedure uses only the
latest BY statement and ignores any previous ones.
If your input data set is not sorted in ascending order, use one of
the following alternatives:
- Sort the data using the SORT procedure with a similar
- Specify the BY statement option NOTSORTED or DESCENDING
in the BY statement for the PLS procedure.
The NOTSORTED option does not mean that the data are
unsorted but rather that the data are arranged in
groups (according to values of the BY variables)
and that these groups are not necessarily in
alphabetical or increasing numeric order.
- Create an index on the BY variables using the DATASETS procedure
(in base SAS software).
For more information on the BY statement, refer to the discussion in
SAS Language Reference: Concepts.
For more information on
the DATASETS procedure, refer to the discussion in
the SAS Procedures Guide.
Copyright © 1999 by SAS Institute Inc., Cary, NC, USA. All rights reserved.