-@node Variable Attributes
-@chapter Manipulating variables
-
-The variables in the active dataset dictionary are important. There are
-several utility functions for examining and adjusting them.
+@c PSPP - a program for statistical analysis.
+@c Copyright (C) 2017, 2020 Free Software Foundation, Inc.
+@c Permission is granted to copy, distribute and/or modify this document
+@c under the terms of the GNU Free Documentation License, Version 1.3
+@c or any later version published by the Free Software Foundation;
+@c with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts.
+@c A copy of the license is included in the section entitled "GNU
+@c Free Documentation License".
+@c
+@node Manipulating Variables
+@chapter Manipulating Variables
+@cindex Variables
+
+Every value in a dataset is associated with a @dfn{variable}.
+Variables describe what the values represent and properties of those values,
+such as the format in which they should be displayed, whether they are numeric
+or alphabetic and how missing values should be represented.
+There are several utility commands for examining and adjusting variables.
@menu
-* ADD VALUE LABELS:: Add value labels to variables.
-* DELETE VARIABLES:: Delete variables.
* DISPLAY:: Display information about the active dataset.
-* FORMATS:: Set print and write formats.
-* LEAVE:: Don't clear variables between cases.
-* MISSING VALUES:: Set missing values for variables.
-* MODIFY VARS:: Rename, reorder, and drop variables.
-* MRSETS:: Add, modify, and list multiple response sets.
* NUMERIC:: Create new numeric variables.
-* PRINT FORMATS:: Set variable print formats.
+* STRING:: Create new string variables.
+* MODIFY VARS:: Rename, reorder, and drop variables.
* RENAME VARIABLES:: Rename variables.
+* SORT VARIABLES:: Reorder variables.
+* DELETE VARIABLES:: Delete variables.
+* VARIABLE LABELS:: Set variable labels for variables.
+* PRINT FORMATS:: Set variable print formats.
+* WRITE FORMATS:: Set variable write formats.
+* FORMATS:: Set print and write formats.
* VALUE LABELS:: Set value labels for variables.
-* STRING:: Create new string variables.
+* ADD VALUE LABELS:: Add value labels to variables.
+* MISSING VALUES:: Set missing values for variables.
* VARIABLE ATTRIBUTE:: Set custom attributes on variables.
-* VARIABLE LABELS:: Set variable labels for variables.
* VARIABLE ALIGNMENT:: Set the alignment for display.
* VARIABLE WIDTH:: Set the display width.
* VARIABLE LEVEL:: Set the measurement level.
+* VARIABLE ROLE:: Set the role that a variable fills in analysis.
* VECTOR:: Declare an array of variables.
-* WRITE FORMATS:: Set variable write formats.
+* MRSETS:: Add, modify, and list multiple response sets.
+* LEAVE:: Don't clear variables between cases.
@end menu
-@node ADD VALUE LABELS
-@section ADD VALUE LABELS
-@vindex ADD VALUE LABELS
-
-@display
-ADD VALUE LABELS
- /var_list value 'label' [value 'label']@dots{}
-@end display
-
-@cmd{ADD VALUE LABELS} has the same syntax and purpose as @cmd{VALUE
-LABELS} (@pxref{VALUE LABELS}), but it does not clear value
-labels from the variables before adding the ones specified.
-
-@node DELETE VARIABLES
-@section DELETE VARIABLES
-@vindex DELETE VARIABLES
-
-@display
-DELETE VARIABLES var_list.
-@end display
-
-@cmd{DELETE VARIABLES} deletes the specified variables from the
-dictionary. It may not be used to delete all variables from the
-dictionary; use @cmd{NEW FILE} to do that (@pxref{NEW FILE}).
-
-@cmd{DELETE VARIABLES} should not be used after defining transformations
-but before executing a procedure. If it is used in such a context, it
-causes the data to be read. If it is used while @cmd{TEMPORARY} is in
-effect, it causes the temporary transformations to become permanent.
-
@node DISPLAY
@section DISPLAY
@vindex DISPLAY
+The @cmd{DISPLAY} command displays information about the variables in the active dataset.
+A variety of different forms of information can be requested.
+By default, all variables in the active dataset are displayed. However you can select
+variables of interest using the @subcmd{/VARIABLES} subcommand.
+
@display
-DISPLAY [SORTED] NAMES [[/VARIABLES=]var_list].
-DISPLAY [SORTED] INDEX [[/VARIABLES=]var_list].
-DISPLAY [SORTED] LABELS [[/VARIABLES=]var_list].
-DISPLAY [SORTED] VARIABLES [[/VARIABLES=]var_list].
-DISPLAY [SORTED] DICTIONARY [[/VARIABLES=]var_list].
-DISPLAY [SORTED] SCRATCH [[/VARIABLES=]var_list].
-DISPLAY [SORTED] ATTRIBUTES [[/VARIABLES=]var_list].
-DISPLAY [SORTED] @@ATTRIBUTES [[/VARIABLES=]var_list].
+DISPLAY [SORTED] NAMES [[/VARIABLES=]@var{var_list}].
+DISPLAY [SORTED] INDEX [[/VARIABLES=]@var{var_list}].
+DISPLAY [SORTED] LABELS [[/VARIABLES=]@var{var_list}].
+DISPLAY [SORTED] VARIABLES [[/VARIABLES=]@var{var_list}].
+DISPLAY [SORTED] DICTIONARY [[/VARIABLES=]@var{var_list}].
+DISPLAY [SORTED] SCRATCH [[/VARIABLES=]@var{var_list}].
+DISPLAY [SORTED] ATTRIBUTES [[/VARIABLES=]@var{var_list}].
+DISPLAY [SORTED] @@ATTRIBUTES [[/VARIABLES=]@var{var_list}].
DISPLAY [SORTED] VECTORS.
@end display
-@cmd{DISPLAY} displays information about the active dataset. A variety
-of different forms of information can be requested.
-
The following keywords primarily cause information about variables to
be displayed. With these keywords, by default information is
displayed about all variable in the active dataset, in the order that
-variables occur in the active dataset dictionary. The SORTED keyword
-causes output to be sorted alphabetically by variable name. The
-VARIABLES subcommand limits output to the specified variables.
+variables occur in the active dataset dictionary. The @subcmd{SORTED} keyword
+causes output to be sorted alphabetically by variable name.
@table @asis
@item NAMES
@item ATTRIBUTES
@itemx @@ATTRIBUTES
Datafile and variable attributes are displayed.
-The first form of the command omits those attributes
+The first form of the command omits those attributes
whose names begin with @code{@@} or @code{$@@}.
In the second for, all datafile and variable attributes are displayed.
@end table
With the @code{VECTOR} keyword, @cmd{DISPLAY} lists all the currently
-declared vectors. If the SORTED keyword is given, the vectors are
+declared vectors. If the @subcmd{SORTED} keyword is given, the vectors are
listed in alphabetical order; otherwise, they are listed in textual
-order of definition within the PSPP syntax file.
+order of definition within the @pspp{} syntax file.
For related commands, see @ref{DISPLAY DOCUMENTS} and @ref{DISPLAY
FILE LABEL}.
-@node FORMATS
-@section FORMATS
-@vindex FORMATS
+@node NUMERIC
+@section NUMERIC
+@vindex NUMERIC
+
+@cmd{NUMERIC} explicitly declares new numeric variables, optionally
+setting their output formats.
@display
-FORMATS var_list (fmt_spec) [var_list (fmt_spec)]@dots{}.
+NUMERIC @var{var_list} [(@var{fmt_spec})] [/@var{var_list} [(@var{fmt_spec})]]@dots{}
@end display
-@cmd{FORMATS} set both print and write formats for the specified
-variables to the specified format specification.
-@xref{Input and Output Formats}.
-
-Specify a list of variables followed by a format specification in
-parentheses. The print and write formats of the specified variables
-will be changed. All of the variables listed together must have
-the same type and, for string variables, the same width.
+Specify the names of the new numeric variables as @var{var_list}. If
+you wish to set the variables' output formats, follow their names by
+an output format specification in parentheses (@pxref{Input and Output
+Formats}); otherwise, the default is F8.2.
-Additional lists of variables and formats may be included following
-the first one.
+Variables created with @cmd{NUMERIC} are initialized to the
+system-missing value.
-@cmd{FORMATS} takes effect immediately. It is not affected by
-conditional and looping structures such as @cmd{DO IF} or @cmd{LOOP}.
+@node STRING
+@section STRING
+@vindex STRING
-@node LEAVE
-@section LEAVE
-@vindex LEAVE
+@cmd{STRING} creates new string variables.
@display
-LEAVE var_list.
+STRING @var{var_list} (@var{fmt_spec}) [/@var{var_list} (@var{fmt_spec})] [@dots{}].
@end display
-@cmd{LEAVE} prevents the specified variables from being
-reinitialized whenever a new case is processed.
-
-Normally, when a data file is processed, every variable in the active
-dataset is initialized to the system-missing value or spaces at the
-beginning of processing for each case. When a variable has been
-specified on @cmd{LEAVE}, this is not the case. Instead, that variable is
-initialized to 0 (not system-missing) or spaces for the first case.
-After that, it retains its value between cases.
+Specify a list of names for the variable you want to create,
+followed by the desired output format specification in
+parentheses (@pxref{Input and Output Formats}).
+Variable widths are
+implicitly derived from the specified output formats.
+The created variables will be initialized to spaces.
-This becomes useful for counters. For instance, in the example below
-the variable SUM maintains a running total of the values in the ITEM
-variable.
+If you want to create several variables with distinct
+output formats, you can either use two or more separate @cmd{STRING} commands,
+or you can specify further variable list and format specification pairs, each separated
+from the previous by a slash (@samp{/}).
+The following example is one way to create three string variables; Two of the
+variables have format A24 and the other A80:
@example
-DATA LIST /ITEM 1-3.
-COMPUTE SUM=SUM+ITEM.
-PRINT /ITEM SUM.
-LEAVE SUM
-BEGIN DATA.
-123
-404
-555
-999
-END DATA.
+STRING firstname lastname (A24) / address (A80).
@end example
-@noindent Partial output from this example:
-
+@noindent Here is another way to achieve the same result:
@example
-123 123.00
-404 527.00
-555 1082.00
-999 2081.00
+STRING firstname lastname (A24).
+STRING address (A80).
@end example
-It is best to use @cmd{LEAVE} command immediately before invoking a
-procedure command, because the left status of variables is reset by
-certain transformations---for instance, @cmd{COMPUTE} and @cmd{IF}.
-Left status is also reset by all procedure invocations.
+@noindent @dots{} and here is yet another way:
-@node MISSING VALUES
-@section MISSING VALUES
-@vindex MISSING VALUES
-
-@display
-MISSING VALUES var_list (missing_values).
-
-missing_values takes one of the following forms:
- num1
- num1, num2
- num1, num2, num3
- num1 THRU num2
- num1 THRU num2, num3
- string1
- string1, string2
- string1, string2, string3
-As part of a range, LO or LOWEST may take the place of num1;
-HI or HIGHEST may take the place of num2.
-@end display
-
-@cmd{MISSING VALUES} sets user-missing values for numeric and string
-variables. Long string variables may have missing values, but
-characters after the first 8 bytes of the missing value must be
-spaces.
-
-Specify a list of variables, followed by a list of their user-missing
-values in parentheses. Up to three discrete values may be given, or,
-for numeric variables only, a range of values optionally accompanied by
-a single discrete value. Ranges may be open-ended on one end, indicated
-through the use of the keyword LO or LOWEST or HI or HIGHEST.
-
-The @cmd{MISSING VALUES} command takes effect immediately. It is not
-affected by conditional and looping constructs such as @cmd{DO IF} or
-@cmd{LOOP}.
+@example
+STRING firstname (A24).
+STRING lastname (A24).
+STRING address (A80).
+@end example
@node MODIFY VARS
@section MODIFY VARS
@vindex MODIFY VARS
-@display
+You can use @cmd{MODIFY VARS} to reorder, rename, or delete variables.
+
+@display
MODIFY VARS
- /REORDER=@{FORWARD,BACKWARD@} @{POSITIONAL,ALPHA@} (var_list)@dots{}
- /RENAME=(old_names=new_names)@dots{}
- /@{DROP,KEEP@}=var_list
- /MAP
+ /REORDER=@{FORWARD,BACKWARD@} @{POSITIONAL,ALPHA@} (@var{var_list})@dots{}
+ /RENAME=(@var{old_names}=@var{new_names})@dots{}
+ /@{DROP,KEEP@}=@var{var_list}
+ /MAP
@end display
-@cmd{MODIFY VARS} reorders, renames, and deletes variables in the
-active dataset.
-
At least one subcommand must be specified, and no subcommand may be
-specified more than once. DROP and KEEP may not both be specified.
+specified more than once. @subcmd{DROP} and @subcmd{KEEP} may not both
+be specified.
-The REORDER subcommand changes the order of variables in the active
+The @subcmd{REORDER} subcommand changes the order of variables in the active
dataset. Specify one or more lists of variable names in parentheses. By
default, each list of variables is rearranged into the specified order.
To put the variables into the reverse of the specified order, put
-keyword BACKWARD before the parentheses. To put them into alphabetical
-order in the dictionary, specify keyword ALPHA before the parentheses.
-BACKWARD and ALPHA may also be combined.
+keyword @subcmd{BACKWARD} before the parentheses. To put them into alphabetical
+order in the dictionary, specify keyword @subcmd{ALPHA} before the parentheses.
+@subcmd{BACKWARD} and @subcmd{ALPHA} may also be combined.
-To rename variables in the active dataset, specify RENAME, an equals sign
+To rename variables in the active dataset, specify @subcmd{RENAME}, an equals sign
(@samp{=}), and lists of the old variable names and new variable names
separated by another equals sign within parentheses. There must be the
same number of old and new variable names. Each old variable is renamed to
the corresponding new variable name. Multiple parenthesized groups of
variables may be specified.
-The DROP subcommand deletes a specified list of variables from the
-active dataset.
+The @subcmd{DROP} subcommand deletes a specified list of variables
+from the active dataset. @cmd{MODIFY VARS} may not be used to delete
+all variables from the dictionary; use @cmd{NEW FILE} to do that
+(@pxref{NEW FILE}).
-The KEEP subcommand keeps the specified list of variables in the active
+The @subcmd{KEEP} subcommand keeps the specified list of variables in the active
dataset. Any unlisted variables are deleted from the active dataset.
-MAP is currently ignored.
+@subcmd{MAP} is currently ignored.
-If either DROP or KEEP is specified, the data is read; otherwise it is
-not.
+If either @subcmd{DROP} or @subcmd{KEEP} is specified, the data is read;
+otherwise it is not.
@cmd{MODIFY VARS} may not be specified following @cmd{TEMPORARY}
(@pxref{TEMPORARY}).
-@node MRSETS
-@section MRSETS
-@vindex MRSETS
-
-@display
-MRSETS
- /MDGROUP NAME=name VARIABLES=var_list VALUE=value
- [CATEGORYLABELS=@{VARLABELS,COUNTEDVALUES@}]
- [@{LABEL='label',LABELSOURCE=VARLABEL@}]
-
- /MCGROUP NAME=name VARIABLES=var_list [LABEL='label']
+@node RENAME VARIABLES
+@section RENAME VARIABLES
+@vindex RENAME VARIABLES
- /DELETE NAME=@{[names],ALL@}
+@cmd{RENAME VARIABLES} changes the names of variables in the active
+dataset.
- /DISPLAY NAME=@{[names],ALL@}
+@display
+RENAME VARIABLES (@var{old_names}=@var{new_names})@dots{} .
@end display
-@cmd{MRSETS} creates, modifies, deletes, and displays multiple
-response sets. A multiple response set is a set of variables that
-represent multiple responses to a single survey question in one of the
-two following ways:
+Specify lists of the old variable names and new
+variable names, separated by an equals sign (@samp{=}), within
+parentheses. There must be the same number of old and new variable
+names. Each old variable is renamed to the corresponding new variable
+name. Multiple parenthesized groups of variables may be specified.
+When the old and new variable names contain only a single variable name,
+the parentheses are optional.
-@itemize @bullet
-@item
-A @dfn{multiple dichotomy set} is analogous to a survey question with
-a set of checkboxes. Each variable in the set is treated in a Boolean
-fashion: one value (the "counted value") means that the box was
-checked, and any other value means that it was not.
+@cmd{RENAME VARIABLES} takes effect immediately. It does not cause the data
+to be read.
-@item
-A @dfn{multiple category set} represents a survey question where the
-respondent is instructed to list up to @var{n} choices. Each variable
-represents one of the responses.
-@end itemize
+@cmd{RENAME VARIABLES} may not be specified following @cmd{TEMPORARY}
+(@pxref{TEMPORARY}).
-Any number of subcommands may be specified in any order.
+@node SORT VARIABLES
+@section SORT VARIABLES
+@vindex SORT VARIABLES
-The MDGROUP subcommand creates a new multiple dichotomy set or
-replaces an existing multiple response set. The NAME, VARIABLES, and
-VALUE specifications are required. The others are optional:
+@cmd{SORT VARIABLES} reorders the variables in the active dataset's dictionary
+according to a chosen sort key.
-@itemize @bullet
-@item
-NAME specifies the name used in syntax for the new multiple dichotomy
-set. The name must begin with @samp{$}; it must otherwise follow the
-rules for identifiers (@pxref{Tokens}).
+@display
+SORT VARIABLES [BY]
+ (NAME | TYPE | FORMAT | LABEL | VALUES | MISSING | MEASURE
+ | ROLE | COLUMNS | ALIGNMENT | ATTRIBUTE @var{name})
+ [(D)].
+@end display
-@item
-VARIABLES specifies the variables that belong to the set. At least
-two variables must be specified. The variables must be all string or
-all numeric.
+The main specification is one of the following identifiers, which
+determines how the variables are sorted:
-@item
-VALUE specifies the counted value. If the variables are numeric, the
-value must be an integer. If the variables are strings, then the
-value must be a string that is no longer than the shortest of the
-variables in the set (ignoring trailing spaces).
+@table @asis
+@item NAME
+Sorts the variables according to their names, in a case-insensitive
+fashion. However, when variable names differ only in a number at the
+end, they are sorted numerically. For example, @code{VAR5} is sorted
+before @code{VAR400} even though @samp{4} precedes @samp{5}.
+
+@item TYPE
+Sorts numeric variables before string variables, and shorter string
+variables before longer ones.
+
+@item FORMAT
+Groups variables by print format; within a format, sorts narrower
+formats before wider ones; with the same format and width, sorts fewer
+decimal places before more decimal places.
+@xref{FORMATS}.
+
+@item LABEL
+Sorts variables without a variable label before those with one.
+@xref{VARIABLE LABELS}.
+
+@item VALUES
+Sorts variables without value labels before those with some.
+@xref{VALUE LABELS}.
+
+@item MISSING
+Sorts variables without missing values before those with some.
+@xref{MISSING VALUES}.
+
+@item MEASURE
+Sorts nominal variables first, followed by ordinal variables, followed
+by scale variables. @xref{VARIABLE LEVEL}.
+
+@item ROLE
+Groups variables according to their role. @xref{VARIABLE ROLE}.
+
+@item COLUMNS
+Sorts variables in ascending display width. @xref{VARIABLE WIDTH}.
+
+@item ALIGNMENT
+Sorts variables according to their alignment, first left-aligned, then
+right-aligned, then centered. @xref{VARIABLE ALIGNMENT}.
+
+@item ATTRIBUTE @var{name}
+Sorts variables according to the first value of their @var{name}
+attribute. Variables without attribute are sorted first.
+@xref{VARIABLE ATTRIBUTE}.
+@end table
-@item
-CATEGORYLABELS optionally specifies the source of the labels for each
-category in the set:
+Only one sort criterion can be specified. The sort is ``stable,'' so
+to sort on multiple criteria one may perform multiple sorts. For
+example, the following will sort primarily based on alignment, with
+variables that have the same alignment ordered based on display width:
-@itemize @minus
-@item
-VARLABELS, the default, uses variable labels or, for variables without
-variable labels, variable names. PSPP warns if two variables have the
-same variable label, since these categories cannot be distinguished in
-output.
+@example
+SORT VARIABLES BY COLUMNS.
+SORT VARIABLES BY ALIGNMENT.
+@end example
-@item
-COUNTEDVALUES instead uses each variable's value label for the counted
-value. PSPP warns if two variables have the same value label for the
-counted value or if one of the variables lacks a value label, since
-such categories cannot be distinguished in output.
-@end itemize
+Specify @code{(D)} to reverse the sort order.
-@item
-LABEL optionally specifies a label for the multiple response set. If
-neither LABEL nor LABELSOURCE=VARLABEL is specified, the set is
-unlabeled.
+@node DELETE VARIABLES
+@section DELETE VARIABLES
+@vindex DELETE VARIABLES
-@item
-LABELSOURCE=VARLABEL draws the multiple response set's label from the
-first variable label among the variables in the set; if none of the
-variables has a label, the name of the first variable is used.
-LABELSOURCE=VARLABEL must be used with CATEGORYLABELS=COUNTEDVALUES.
-It is mutually exclusive with LABEL.
-@end itemize
+@cmd{DELETE VARIABLES} deletes the specified variables from the dictionary.
-The MCGROUP subcommand creates a new multiple category set or
-replaces an existing multiple response set. The NAME and VARIABLES
-specifications are required, and LABEL is optional. Their meanings
-are as described above to MDGROUP. PSPP warns if two variables in the
-set have different value labels for a single value, since each of the
-variables in the set should have the same possible categories.
+@display
+DELETE VARIABLES @var{var_list}.
+@end display
-The DELETE subcommand deletes multiple response groups. A list of
-groups may be named within a set of required square brackets, or ALL
-may be used to delete all groups.
+@cmd{DELETE VARIABLES} should not be used after defining transformations
+but before executing a procedure. If it is used in such a context, it
+causes the data to be read. If it is used while @cmd{TEMPORARY} is in
+effect, it causes the temporary transformations to become permanent.
-The DISPLAY subcommand displays information about defined multiple
-response sets. Its syntax is the same as the DELETE subcommand.
+@cmd{DELETE VARIABLES} may not be used to delete all variables from the
+dictionary; use @cmd{NEW FILE} to do that (@pxref{NEW FILE}).
-Multiple response sets are saved to and read from system files by,
-e.g., the @cmd{SAVE} and @cmd{GET} command. Otherwise, multiple
-response sets are currently used only by third party software.
+@node VARIABLE LABELS
+@section VARIABLE LABELS
+@vindex VARIABLE LABELS
-@node NUMERIC
-@section NUMERIC
-@vindex NUMERIC
+In addition to a variable's name, each variable can have a @dfn{label}.
+Whereas the name is limited to certain constraints (@pxref{Attributes}) a variable's
+label has no such constraints.
+Typically, the names are concise, easy to type mnemonics for the variable
+and the labels are longer, more verbose descriptions.
@display
-NUMERIC /var_list [(fmt_spec)].
+VARIABLE LABELS
+ @var{var_list} '@var{var_label}'
+ [ /@var{var_list} '@var{var_label}']
+ .
+ .
+ .
+ [ /@var{var_list} '@var{var_label}']
@end display
-@cmd{NUMERIC} explicitly declares new numeric variables, optionally
-setting their output formats.
-
-Specify a slash (@samp{/}), followed by the names of the new numeric
-variables. If you wish to set their output formats, follow their names
-by an output format specification in parentheses (@pxref{Input and Output
-Formats}); otherwise, the default is F8.2.
+@cmd{VARIABLE LABELS} associates explanatory names
+with variables. This name, called a @dfn{variable label}, is displayed by
+statistical procedures.
-Variables created with @cmd{NUMERIC} are initialized to the
-system-missing value.
+To assign a variable label to a group of variables, specify a
+list of variable names and the variable label as a string.
+To assign different labels to different variables in the same command,
+precede the subsequent variable list with a slash (@samp{/}).
@node PRINT FORMATS
@section PRINT FORMATS
@vindex PRINT FORMATS
@display
-PRINT FORMATS var_list (fmt_spec) [var_list (fmt_spec)]@dots{}.
+PRINT FORMATS @var{var_list} (@var{fmt_spec}) [@var{var_list} (@var{fmt_spec})]@dots{}.
@end display
@cmd{PRINT FORMATS} sets the print formats for the specified
Its syntax is identical to that of @cmd{FORMATS} (@pxref{FORMATS}),
but @cmd{PRINT FORMATS} sets only print formats, not write formats.
-@node RENAME VARIABLES
-@section RENAME VARIABLES
-@vindex RENAME VARIABLES
+@node WRITE FORMATS
+@section WRITE FORMATS
+@vindex WRITE FORMATS
@display
-RENAME VARIABLES (old_names=new_names)@dots{} .
+WRITE FORMATS @var{var_list} (@var{fmt_spec}) [@var{var_list} (@var{fmt_spec})]@dots{}.
@end display
-@cmd{RENAME VARIABLES} changes the names of variables in the active
-dataset. Specify lists of the old variable names and new
-variable names, separated by an equals sign (@samp{=}), within
-parentheses. There must be the same number of old and new variable
-names. Each old variable is renamed to the corresponding new variable
-name. Multiple parenthesized groups of variables may be specified.
+@cmd{WRITE FORMATS} sets the write formats for the specified variables
+to the specified format specification. Its syntax is identical to
+that of @cmd{FORMATS} (@pxref{FORMATS}), but @cmd{WRITE FORMATS} sets only
+write formats, not print formats.
-@cmd{RENAME VARIABLES} takes effect immediately. It does not cause the data
-to be read.
+@node FORMATS
+@section FORMATS
+@vindex FORMATS
-@cmd{RENAME VARIABLES} may not be specified following @cmd{TEMPORARY}
-(@pxref{TEMPORARY}).
+@display
+FORMATS @var{var_list} (@var{fmt_spec}) [@var{var_list} (@var{fmt_spec})]@dots{}.
+@end display
+
+@cmd{FORMATS} set both print and write formats for the specified
+variables to the specified format specification.
+@xref{Input and Output Formats}.
+
+Specify a list of variables followed by a format specification in
+parentheses. The print and write formats of the specified variables
+will be changed. All of the variables listed together must have
+the same type and, for string variables, the same width.
+
+Additional lists of variables and formats may be included following
+the first one.
+
+@cmd{FORMATS} takes effect immediately. It is not affected by
+conditional and looping structures such as @cmd{DO IF} or @cmd{LOOP}.
@node VALUE LABELS
@section VALUE LABELS
@vindex VALUE LABELS
-@display
+The values of a variable can be associated with an arbitrary text string.
+In this way, a short value can stand for a longer, more descriptive label.
+
+Both numeric and string variables can be given labels. For string
+variables, the values are case-sensitive, so that, for example, a
+capitalized value and its lowercase variant would have to be labeled
+separately if both are present in the data.
+
+@display
VALUE LABELS
- /var_list value 'label' [value 'label']@dots{}
+ /@var{var_list} @var{value} '@var{label}' [@var{value} '@var{label}']@dots{}
@end display
-@cmd{VALUE LABELS} allows values of numeric and short string
-variables to be associated with labels. In this way, a short value can
-stand for a long value.
+@cmd{VALUE LABELS} allows values of variables to be associated with labels.
-To set up value labels for a set of variables, specify the
+To set up value labels for one or more variables, specify the
variable names after a slash (@samp{/}), followed by a list of values
and their associated labels, separated by spaces.
(@pxref{ADD VALUE LABELS}) to add value labels without clearing those
already present.
-@node STRING
-@section STRING
-@vindex STRING
+@node ADD VALUE LABELS
+@section ADD VALUE LABELS
+@vindex ADD VALUE LABELS
+
+@cmd{ADD VALUE LABELS} has the same syntax and purpose as @cmd{VALUE
+LABELS} (@pxref{VALUE LABELS}), but it does not clear value
+labels from the variables before adding the ones specified.
@display
-STRING /var_list (fmt_spec).
+ADD VALUE LABELS
+ /@var{var_list} @var{value} '@var{label}' [@var{value} '@var{label}']@dots{}
@end display
-@cmd{STRING} creates new string variables for use in
-transformations.
-Specify a slash (@samp{/}), followed by the names of the string
-variables to create and the desired output format specification in
-parentheses (@pxref{Input and Output Formats}). Variable widths are
-implicitly derived from the specified output formats.
+@node MISSING VALUES
+@section MISSING VALUES
+@vindex MISSING VALUES
+
+In many situations the data available for analysis is incomplete and a placeholder
+must be used in place of a value to indicate that the value is unknown. One way
+that missing values are represented is through the $SYSMIS variable
+(@pxref{System Variables}). Another, more flexible way is through
+@dfn{user-missing values} which are determined on a per variable basis.
-Created variables are initialized to spaces.
+The @cmd{MISSING VALUES} command sets user-missing values for variables.
+@display
+MISSING VALUES @var{var_list} (@var{missing_values}).
+
+where @var{missing_values} takes one of the following forms:
+ @var{num1}
+ @var{num1}, @var{num2}
+ @var{num1}, @var{num2}, @var{num3}
+ @var{num1} THRU @var{num2}
+ @var{num1} THRU @var{num2}, @var{num3}
+ @var{string1}
+ @var{string1}, @var{string2}
+ @var{string1}, @var{string2}, @var{string3}
+As part of a range, @subcmd{LO} or @subcmd{LOWEST} may take the place of @var{num1};
+@subcmd{HI} or @subcmd{HIGHEST} may take the place of @var{num2}.
+@end display
+
+@cmd{MISSING VALUES} sets user-missing values for numeric and string
+variables. Long string variables may have missing values, but
+characters after the first 8 bytes of the missing value must be
+spaces.
+
+Specify a list of variables, followed by a list of their user-missing
+values in parentheses. Up to three discrete values may be given, or,
+for numeric variables only, a range of values optionally accompanied by
+a single discrete value. Ranges may be open-ended on one end, indicated
+through the use of the
+keyword @subcmd{LO} or @subcmd{LOWEST} or @subcmd{HI} or @subcmd{HIGHEST}.
+
+The @cmd{MISSING VALUES} command takes effect immediately. It is not
+affected by conditional and looping constructs such as @cmd{DO IF} or
+@cmd{LOOP}.
@node VARIABLE ATTRIBUTE
@section VARIABLE ATTRIBUTE
@vindex VARIABLE ATTRIBUTE
-@display
-VARIABLE ATTRIBUTE
- VARIABLES=var_list
- ATTRIBUTE=name('value') [name('value')]@dots{}
- ATTRIBUTE=name@b{[}index@b{]}('value') [name@b{[}index@b{]}('value')]@dots{}
- DELETE=name [name]@dots{}
- DELETE=name@b{[}index@b{]} [name@b{[}index@b{]}]@dots{}
-@end display
-
@cmd{VARIABLE ATTRIBUTE} adds, modifies, or removes user-defined
attributes associated with variables in the active dataset. Custom
-variable attributes are not interpreted by PSPP, but they are saved as
+variable attributes are not interpreted by @pspp{}, but they are saved as
part of system files and may be used by other software that reads
them.
-The required VARIABLES subcommand must come first. Specify the
-variables to which the following ATTRIBUTE or DELETE subcommand
+@display
+VARIABLE ATTRIBUTE
+ VARIABLES=@var{var_list}
+ ATTRIBUTE=@var{name}('@var{value}') [@var{name}('@var{value}')]@dots{}
+ ATTRIBUTE=@var{name}@b{[}@var{index}@b{]}('@var{value}') [@var{name}@b{[}@var{index}@b{]}('@var{value}')]@dots{}
+ DELETE=@var{name} [@var{name}]@dots{}
+ DELETE=@var{name}@b{[}@var{index}@b{]} [@var{name}@b{[}@var{index}@b{]}]@dots{}
+@end display
+
+The required @subcmd{VARIABLES} subcommand must come first. Specify the
+variables to which the following @subcmd{ATTRIBUTE} or @subcmd{DELETE} subcommand
should apply.
-Use the ATTRIBUTE subcommand to add or modify custom variable
+Use the @subcmd{ATTRIBUTE} subcommand to add or modify custom variable
attributes. Specify the name of the attribute as an identifier
(@pxref{Tokens}), followed by the desired value, in parentheses, as a
quoted string. The specified attributes are then added or modified in
-the variables specified on VARIABLES. Attribute names that begin with
-@code{$} are reserved for PSPP's internal use, and attribute names
-that begin with @code{@@} or @code{$@@} are not displayed by most PSPP
+the variables specified on @subcmd{VARIABLES}. Attribute names that begin with
+@code{$} are reserved for @pspp{}'s internal use, and attribute names
+that begin with @code{@@} or @code{$@@} are not displayed by most @pspp{}
commands that display other attributes. Other attribute names are not
treated specially.
indexes start at 1, not 0. An attribute array that has a single
element (number 1) is not distinguished from a non-array attribute.
-Use the DELETE subcommand to delete an attribute from the variable
-specified on VARIABLES. Specify an attribute name by itself to delete
+Use the @subcmd{DELETE} subcommand to delete an attribute from the variable
+specified on @subcmd{VARIABLES}. Specify an attribute name by itself to delete
an entire attribute, including all array elements for attribute
arrays. Specify an attribute name followed by an array index in
square brackets to delete a single element of an attribute array. In
by conditional and looping structures such as @cmd{DO IF} or
@cmd{LOOP}.
-@node VARIABLE LABELS
-@section VARIABLE LABELS
-@vindex VARIABLE LABELS
-
-@display
-VARIABLE LABELS
- var_list 'var_label'
- [ /var_list 'var_label']
- .
- .
- .
- [ /var_list 'var_label']
-@end display
-
-@cmd{VARIABLE LABELS} associates explanatory names
-with variables. This name, called a @dfn{variable label}, is displayed by
-statistical procedures.
-
-To assign a variable label to a group of variables, specify a
-list of variable names and the variable label as a string.
-To assign different labels to different variables in the same command,
-precede the subsequent variable list with a slash (@samp{/}).
-
-
@node VARIABLE ALIGNMENT
-@comment node-name, next, previous, u
@section VARIABLE ALIGNMENT
@vindex VARIABLE ALIGNMENT
+@cmd{VARIABLE ALIGNMENT} sets the alignment of variables for display editing
+purposes. It does not affect the display of variables in the @pspp{} output.
+
@display
VARIABLE ALIGNMENT
- var_list ( LEFT | RIGHT | CENTER )
- [ /var_list ( LEFT | RIGHT | CENTER ) ]
+ @var{var_list} ( LEFT | RIGHT | CENTER )
+ [ /@var{var_list} ( LEFT | RIGHT | CENTER ) ]
.
.
.
- [ /var_list ( LEFT | RIGHT | CENTER ) ]
+ [ /@var{var_list} ( LEFT | RIGHT | CENTER ) ]
@end display
-@cmd{VARIABLE ALIGNMENT} sets the alignment of variables for display editing
-purposes. This only has effect for third party software. It does not affect
-the display of variables in the PSPP output.
-
-
-
-
@node VARIABLE WIDTH
-@comment node-name, next, previous, up
@section VARIABLE WIDTH
@vindex VARIABLE WIDTH
@display
VARIABLE WIDTH
- var_list (width)
- [ /var_list (width) ]
+ @var{var_list} (width)
+ [ /@var{var_list} (width) ]
.
.
.
- [ /var_list (width) ]
+ [ /@var{var_list} (width) ]
@end display
@cmd{VARIABLE WIDTH} sets the column width of variables for display editing
-purposes. This only affects third party software. It does not affect
-the display of variables in the PSPP output.
+purposes. It does not affect the display of variables in the @pspp{} output.
@node VARIABLE LEVEL
-@comment node-name, next, previous, up
@section VARIABLE LEVEL
@vindex VARIABLE LEVEL
@display
-VARIABLE LEVEL
- var_list ( SCALE | NOMINAL | ORDINAL )
- [ /var_list ( SCALE | NOMINAL | ORDINAL ) ]
- .
- .
- .
- [ /var_list ( SCALE | NOMINAL | ORDINAL ) ]
+@t{VARIABLE LEVEL} @i{variables} @t{(}@{@t{SCALE} @math{|} @t{NOMINAL} @math{|} @t{ORDINAL}@}@t{)}@dots{}
+@end display
+
+@cmd{VARIABLE LEVEL} sets the measurement level of @var{variables} as
+specified. @xref{Attributes}, for the definitions of the available
+measurement levels.
+
+@node VARIABLE ROLE
+@section VARIABLE ROLE
+@vindex VARIABLE ROLE
+@display
+VARIABLE ROLE
+ /@var{role} @var{var_list}
+ [/@var{role} @var{var_list}]@dots{}
@end display
-@cmd{VARIABLE LEVEL} sets the measurement level of variables.
-Currently, this has no effect except for certain third party software.
+@cmd{VARIABLE ROLE} sets the intended role of a variable for use in
+dialog boxes in graphical user interfaces. Each @var{role} specifies
+one of the following roles for the variables that follow it:
+
+@table @code
+@item INPUT
+An input variable, such as an independent variable.
+@item TARGET
+An output variable, such as an dependent variable.
+
+@item BOTH
+A variable used for input and output.
+
+@item NONE
+No role assigned. (This is a variable's default role.)
+
+@item PARTITION
+Used to break the data into groups for testing.
+
+@item SPLIT
+No meaning except for certain third party software. (This role's
+meaning is unrelated to @cmd{SPLIT FILE}.)
+@end table
+
+The PSPPIRE GUI does not yet use variable roles as intended.
@node VECTOR
@section VECTOR
@display
Two possible syntaxes:
- VECTOR vec_name=var_list.
- VECTOR vec_name_list(count [format]).
+ VECTOR @var{vec_name}=@var{var_list}.
+ VECTOR @var{vec_name_list}(@var{count} [@var{format}]).
@end display
@cmd{VECTOR} allows a group of variables to be accessed as if they
To make a vector out of a set of existing variables, specify a name
for the vector followed by an equals sign (@samp{=}) and the variables
-to put in the vector. All the variables in the vector must be the same
-type. String variables in a vector must all have the same width.
+to put in the vector. The variables must be all numeric or all
+string, and string variables must have the same width.
To make a vector and create variables at the same time, specify one or
-more vector names followed by a count in parentheses. This will cause
-variables named @code{@var{vec}1} through @code{@var{vec}@var{count}}
-to be created as numeric variables. By default, the new variables
-have print and write format F8.2, but an alternate format may be
-specified inside the parentheses before or after the count and
-separated from it by white space or a comma. Variable names including
-numeric suffixes may not exceed 64 characters in length, and none of
-the variables may exist prior to @cmd{VECTOR}.
+more vector names followed by a count in parentheses. This will
+create variables named @code{@var{vec}1} through
+@code{@var{vec}@var{count}}. By default, the new variables are
+numeric with format F8.2, but an alternate format may be specified
+inside the parentheses before or after the count and separated from it
+by white space or a comma. With a string format such as A8, the
+variables will be string variables; with a numeric format, they will
+be numeric. Variable names including the suffixes may not exceed 64
+characters in length, and none of the variables may exist prior to
+@cmd{VECTOR}.
Vectors created with @cmd{VECTOR} disappear after any procedure or
procedure-like command is executed. The variables contained in the
Variables within a vector may be referenced in expressions using
@code{vector(index)} syntax.
-@node WRITE FORMATS
-@section WRITE FORMATS
-@vindex WRITE FORMATS
+@node MRSETS
+@section MRSETS
+@vindex MRSETS
+
+@cmd{MRSETS} creates, modifies, deletes, and displays multiple
+response sets. A multiple response set is a set of variables that
+represent multiple responses to a survey question.
+
+Multiple responses are represented in one of the two following ways:
+
+@itemize @bullet
+@item
+A @dfn{multiple dichotomy set} is analogous to a survey question with
+a set of checkboxes. Each variable in the set is treated in a Boolean
+fashion: one value (the "counted value") means that the box was
+checked, and any other value means that it was not.
+
+@item
+A @dfn{multiple category set} represents a survey question where the
+respondent is instructed to list up to @var{n} choices. Each variable
+represents one of the responses.
+@end itemize
@display
-WRITE FORMATS var_list (fmt_spec) [var_list (fmt_spec)]@dots{}.
+MRSETS
+ /MDGROUP NAME=@var{name} VARIABLES=@var{var_list} VALUE=@var{value}
+ [CATEGORYLABELS=@{VARLABELS,COUNTEDVALUES@}]
+ [@{LABEL='@var{label}',LABELSOURCE=VARLABEL@}]
+
+ /MCGROUP NAME=@var{name} VARIABLES=@var{var_list} [LABEL='@var{label}']
+
+ /DELETE NAME=@{[@var{names}],ALL@}
+
+ /DISPLAY NAME=@{[@var{names}],ALL@}
@end display
-@cmd{WRITE FORMATS} sets the write formats for the specified variables
-to the specified format specification. Its syntax is identical to
-that of FORMATS (@pxref{FORMATS}), but @cmd{WRITE FORMATS} sets only
-write formats, not print formats.
+
+Any number of subcommands may be specified in any order.
+
+The @subcmd{MDGROUP} subcommand creates a new multiple dichotomy set or
+replaces an existing multiple response set. The @subcmd{NAME},
+@subcmd{VARIABLES}, and
+@subcmd{VALUE} specifications are required. The others are optional:
+
+@itemize @bullet
+@item
+@var{NAME} specifies the name used in syntax for the new multiple dichotomy
+set. The name must begin with @samp{$}; it must otherwise follow the
+rules for identifiers (@pxref{Tokens}).
+
+@item
+@subcmd{VARIABLES} specifies the variables that belong to the set. At least
+two variables must be specified. The variables must be all string or
+all numeric.
+
+@item
+@subcmd{VALUE} specifies the counted value. If the variables are numeric, the
+value must be an integer. If the variables are strings, then the
+value must be a string that is no longer than the shortest of the
+variables in the set (ignoring trailing spaces).
+
+@item
+@subcmd{CATEGORYLABELS} optionally specifies the source of the labels for each
+category in the set:
+
+@itemize @minus
+@item
+@subcmd{VARLABELS}, the default, uses variable labels or, for variables without
+variable labels, variable names. @pspp{} warns if two variables have the
+same variable label, since these categories cannot be distinguished in
+output.
+
+@item
+@subcmd{COUNTEDVALUES} instead uses each variable's value label for the counted
+value. @pspp{} warns if two variables have the same value label for the
+counted value or if one of the variables lacks a value label, since
+such categories cannot be distinguished in output.
+@end itemize
+
+@item
+@subcmd{LABEL} optionally specifies a label for the multiple response set. If
+neither @subcmd{LABEL} nor @subcmd{LABELSOURCE=VARLABEL} is specified, the set is
+unlabeled.
+
+@item
+@subcmd{LABELSOURCE=VARLABEL} draws the multiple response set's label from the
+first variable label among the variables in the set; if none of the
+variables has a label, the name of the first variable is used.
+@subcmd{LABELSOURCE=VARLABEL} must be used with @subcmd{CATEGORYLABELS=COUNTEDVALUES}.
+It is mutually exclusive with @subcmd{LABEL}.
+@end itemize
+
+The @subcmd{MCGROUP} subcommand creates a new multiple category set or
+replaces an existing multiple response set. The @subcmd{NAME} and @subcmd{VARIABLES}
+specifications are required, and @subcmd{LABEL} is optional. Their meanings
+are as described above in @subcmd{MDGROUP}. @pspp{} warns if two variables in the
+set have different value labels for a single value, since each of the
+variables in the set should have the same possible categories.
+
+The @subcmd{DELETE} subcommand deletes multiple response groups. A list of
+groups may be named within a set of required square brackets, or ALL
+may be used to delete all groups.
+
+The @subcmd{DISPLAY} subcommand displays information about defined multiple
+response sets. Its syntax is the same as the @subcmd{DELETE} subcommand.
+
+Multiple response sets are saved to and read from system files by,
+@i{e.g.}, the @cmd{SAVE} and @cmd{GET} command. Otherwise, multiple
+response sets are currently used only by third party software.
+
+@node LEAVE
+@section LEAVE
+@vindex LEAVE
+
+@cmd{LEAVE} prevents the specified variables from being
+reinitialized whenever a new case is processed.
+
+@display
+LEAVE @var{var_list}.
+@end display
+
+Normally, when a data file is processed, every variable in the active
+dataset is initialized to the system-missing value or spaces at the
+beginning of processing for each case. When a variable has been
+specified on @cmd{LEAVE}, this is not the case. Instead, that variable is
+initialized to 0 (not system-missing) or spaces for the first case.
+After that, it retains its value between cases.
+
+This becomes useful for counters. For instance, in the example below
+the variable @code{SUM} maintains a running total of the values in the @code{ITEM}
+variable.
+
+@example
+DATA LIST /ITEM 1-3.
+COMPUTE SUM=SUM+ITEM.
+PRINT /ITEM SUM.
+LEAVE SUM
+BEGIN DATA.
+123
+404
+555
+999
+END DATA.
+@end example
+
+@noindent Partial output from this example:
+
+@example
+123 123.00
+404 527.00
+555 1082.00
+999 2081.00
+@end example
+
+It is best to use @cmd{LEAVE} command immediately before invoking a
+procedure command, because the left status of variables is reset by
+certain transformations---for instance, @cmd{COMPUTE} and @cmd{IF}.
+Left status is also reset by all procedure invocations.
+
projects / pspp / blobdiff