Each variable has a set of value labels (see VALUE LABELS in PSPP Users Guide), represented as
struct val_labs. A
struct val_labs is essentially a map from
union values to strings.
All of the values in a set of value labels have the same width, which
for a set of value labels owned by a variable (the common case) is the
same as its variable.
Sets of value labels may contain any number of entries.
It is rarely necessary to interact directly with a
object. Instead, the most common operation, looking up the label for
a value of a given variable, can be conveniently executed through
struct variable. See Variable Value Labels, for
Function prototypes and other declarations related to missing values are declared in data/value-labels.h.
Opaque type that represents a set of value labels.
The most often useful function for value labels is
val_labs_find, for looking up the label associated with a
Looks in val_labs for a label for the given value. Returns the label, if one is found, or a null pointer otherwise.
Several other functions for working with value labels are described in the following section, but these are more rarely useful.
|• Value Labels Creation and Destruction:|
|• Value Labels Properties:|
|• Value Labels Adding and Removing Labels:|
|• Value Labels Iteration:|