doc: Document that value labels are case sensitive.

[pspp] / doc / variables.texi

diff --git a/doc/variables.texi b/doc/variables.texi
index f4ed4449dd52aeb713b8fb1959dceb63278b8c07..68a996681d1db8830c4d256ab65c15ff2d701947 100644 (file)
--- a/doc/variables.texi
+++ b/doc/variables.texi
@@ -23,6 +23,7 @@ several utility functions for examining and adjusting them.
 * 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.
 @end menu
@@ -433,6 +434,8 @@ 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.
 
 @cmd{RENAME VARIABLES} takes effect immediately.  It does not cause the data
 to be read.
@@ -449,11 +452,16 @@ VALUE LABELS
         /@var{var_list} @var{value} '@var{label}' [@var{value} '@var{label}']@dots{}
 @end display
 
-@cmd{VALUE LABELS} allows values of numeric and short string
+@cmd{VALUE LABELS} allows values of
 variables to be associated with labels.  In this way, a short value can
-stand for a long value.
+stand for a longer, more descriptive label.
 
-To set up value labels for a set of variables, specify the
+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.
+
+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.
 
@@ -646,6 +654,42 @@ VARIABLE LEVEL
 Currently, this has no effect except for certain third party software.
 
 
+@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 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
 @vindex VECTOR