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2.5 Variables

A PSPP variable is represented by struct variable, an opaque type declared in data/variable.h along with related declarations. See Variables in PSPP Users Guide, for a description of PSPP variables from a user perspective.

PSPP is unusual among computer languages in that, by itself, a PSPP variable does not have a value. Instead, a variable in PSPP takes on a value only in the context of a case, which supplies one value for each variable in a set of variables (see Cases). The set of variables in a case, in turn, are ordinarily part of a dictionary (see Dictionaries).

Every variable has several attributes, most of which correspond directly to one of the variable attributes visible to PSPP users (see Attributes in PSPP Users Guide).

The following sections describe variable-related functions and macros.