@chapter Combining Data Files
This chapter describes commands that allow data from system files,
-portable file, scratch files, and the active file to be combined to
-form a new active file. These commands can combine data files in the
+portable files, and open datasets to be combined to
+form a new active dataset. These commands can combine data files in the
following ways:
@itemize
following sections describe details specific to each command.
Each of these commands reads two or more input files and combines
-them. The command's output becomes the new active file. The input
+them. The command's output becomes the new active dataset. The input
files are not changed on disk.
The syntax of each command begins with a specification of the files to
-be read as input. For each input file, specify FILE with a system,
-portable, or scratch file's name as a string or a file handle
-(@pxref{File Handles}), or specify an asterisk (@samp{*}) to use the
-active file as input. Use of portable or scratch files on FILE is a
+be read as input. For each input file, specify FILE with a system
+file or portable file's name as a string, a dataset (@pxref{Datasets})
+or file handle name, (@pxref{File Handles}), or an asterisk (@samp{*})
+to use the active dataset as input. Use of portable files on FILE is a
PSPP extension.
-At least two FILE subcommands must be specified. If the active file
+At least two FILE subcommands must be specified. If the active dataset
is used as an input source, then @cmd{TEMPORARY} must not be in
effect.
variables before it applies it to the command. When SORT is used, BY
is required. SORT is a PSPP extension.
-PSPP merges the dictionaries of all of the input files to form the new
-active file dictionary, like so:
+PSPP merges the dictionaries of all of the input files to form the
+dictionary of the new active dataset, like so:
@itemize @bullet
@item
-The new active file's variables are the union of all the input files'
+The variables in the new active dataset are the union of all the input files'
variables, matched based on their name. When a single input file
contains a variable with a given name, the output file will contain
exactly that variable. When more than one input file contains a
similarly for value labels and missing values.
@item
-The new active file's file label (@pxref{FILE LABEL}) is that of the
+The file label of the new active dataset (@pxref{FILE LABEL}) is that of the
first specified FILE that has a file label.
@item
-The new active file's documents (@pxref{DOCUMENT}) are the
+The documents in the new active dataset (@pxref{DOCUMENT}) are the
concatenation of all the input files' documents, in the order in which
the FILE subcommands are specified.
@item
If all of the input files are weighted on the same variable, then the
-new active file is weighted on that variable. Otherwise, the new
-active file is not weighted.
+new active dataset is weighted on that variable. Otherwise, the new
+active dataset is not weighted.
@end itemize
The remaining subcommands apply to the output file as a whole, rather
listed are dropped. DROP and KEEP are executed in left-to-right order
and may be repeated any number of times. DROP and KEEP do not affect
variables created by the IN, FIRST, and LAST subcommands, which are
-always included in the new active file, but they can be used to drop
+always included in the new active dataset, but they can be used to drop
BY variables.
The FIRST and LAST subcommands are optional. They may only be
specified on @cmd{MATCH FILES} and @cmd{ADD FILES}, and only when BY
is used. FIRST and LIST each adds a numeric variable to the new
-active file, with the name given as the subcommand's argument and F1.0
+active dataset, with the name given as the subcommand's argument and F1.0
print and write formats. The value of the FIRST variable is 1 in the
first output case with a given set of values for the BY variables, and
0 in other cases. Similarly, the LAST variable is 1 in the last case
@end display
@cmd{ADD FILES} adds cases from multiple input files. The output,
-which replaces the active file, consists all of the cases in all of
+which replaces the active dataset, consists all of the cases in all of
the input files.
ADD FILES shares the bulk of its syntax with other PSPP commands for