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Chapter 6: The pspp language
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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.
Type
Numeric or string.
Width
(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.
Position
Variables in the dictionary are arranged in a specific order. DISPLAY can be
used to show this order: see Section 11.3 [DISPLAY], page 100.
Initialization
Either reinitialized to 0 or spaces for each case, or left at its existing value. See
Section 11.5 [LEAVE], page 101.
Missing values
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 systemmissing value is not a value at all. See Section 6.6 [Missing Observations],
page 32.
Variable label
A string that describes the variable. See Section 11.15 [VARIABLE LABELS],
page 107.
Value label
Optionally, these associate each possible value of the variable with a string. See
Section 11.12 [VALUE LABELS], page 105.
Print format
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 Section 6.7.4 [Input and
Output Formats], page 34.
Write format
Similar to print format, but used by the WRITE command (see Section 8.17
[WRITE], page 80).
Custom attributes
User-defined associations between names and values. See Section 11.14 [VARIABLE ATTRIBUTE], page 106.
Role
The intended role of a variable for use in dialog boxes in graphical user interfaces. See Section 11.19 [VARIABLE ROLE], page 108.