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Each variable has a number of attributes, including:
An identifier, up to 64 bytes long. Each variable must have a different name. See Tokens.
Some system variable names begin with ‘$’, but user-defined variables’ names may not begin with ‘$’.
The final character in a variable name should not be ‘.’, because
such an identifier will be misinterpreted when it is the final token
on a line: FOO.
is divided into two separate tokens,
‘FOO’ and ‘.’, indicating end-of-command. See Tokens.
The final character in a variable name should not be ‘_’, because some such identifiers are used for special purposes by PSPP procedures.
As with all PSPP identifiers, variable names are not case-sensitive. PSPP capitalizes variable names on output the same way they were capitalized at their point of definition in the input.
Numeric or string.
(string variables only) String variables with a width of 8 characters or fewer are called short string variables. Short string variables may be used in a few contexts where long string variables (those with widths greater than 8) are not allowed.
Variables in the dictionary are arranged in a specific order.
DISPLAY
can be used to show this order: see DISPLAY.
Either reinitialized to 0 or spaces for each case, or left at its existing value. See LEAVE.
Optionally, up to three values, or a range of values, or a specific value plus a range, can be specified as user-missing values. There is also a system-missing value that is assigned to an observation when there is no other obvious value for that observation. Observations with missing values are automatically excluded from analyses. User-missing values are actual data values, while the system-missing value is not a value at all. See Handling missing observations.
A string that describes the variable. See VARIABLE LABELS.
Optionally, these associate each possible value of the variable with a string. See VALUE LABELS.
Display width, format, and (for numeric variables) number of decimal places. This attribute does not affect how data are stored, just how they are displayed. Example: a width of 8, with 2 decimal places. See Input and Output Formats.
Similar to print format, but used by the WRITE
command
(see WRITE).
User-defined associations between names and values. See VARIABLE ATTRIBUTE.
The intended role of a variable for use in dialog boxes in graphical user interfaces. See VARIABLE ROLE.
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