This is documentation for Mathematica 6, which was
based on an earlier version of the Wolfram Language.
View current documentation (Version 11.2)


represents data that is missing.
specifies a reason for the data being missing.
Missing["reason", expr]
associates the expression expr with the missing data.
  • Missing[...] is a symbolic object, with no default evaluation rules defined.
  • Typical examples of "reason" include "NotApplicable", "Unknown", "NotAvailable", "Nonexistent", "Indeterminate", "Variable", "Disputed" or "TooLarge".
  • Plotting functions automatically omit Missing objects when plotting data.
New in 6