Undefined values in tables

[Don]

Good day,

What does it mean to have "undefined" values in a table? How can I manipulate or recode them? I've tried using the following in the tab logic but it doesn't seem to do anything.

Code: Select all

recode Age => Age;
undefined => 999;
endrecode;

When I wrote similar code to recode "not applicable" values it worked. So what's different about the undefined special value?

[Gregory Martin]

Undefined values are values that are not in your value set but that have a value (unlike not applicable values). So say you have a value set for Sex with values 1 for Male and 2 for Female, then codes 0 and 3 - 9 would be listed in the Undefined category.