Merging two data files
!MERGE c f
!SKIP n !MATCH a b
may be specified on a line following the datafile
The purpose is to combine data fields from the (primary) data file
with data fields from a secondary file (f).
The effect is to open the named file (skip n lines)
and then insert the columns from the new file into field
positions starting at position c.
a b is specified, ASReml checks that the field
a (0< a < c) has the same value as field b.
If not, it is assumed that the merged file has some missing records
and missing values are inserted into the data record and the line
file is kept for comparison with the next record.
At this stage it is expected that the lines in the
are in the same order as the corresponding lines occur in the
primary data file, and that there are no extraneous lines in the
file. (It is proposed to extend this so the orders do not need
to agree and that multiple lines in the primary file could
be merged with the same line of the
For example, assuming the field definitions define 10 fields,
PRIMARY.DAT !skip 1
!MERGE 6 SECOND.DAT !SKIP 1 !MATCH 1 6
would obtain the first five fields from PRIMARY.DAT and the next five
from SECOND.DAT, checking that the first field in each file has the
Thus each input record is obtained by combining information from
each file, before any transformations are performed.
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