Wolfram Language & System 10.0 (2014)|Legacy Documentation

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is an option for InputForm and related functions that specifies whether marks should be included in the printed forms of approximate numbers.


  • The default setting for NumberMarks is given by the value of $NumberMarks.
  • NumberMarks->True indicates that should be used in all approximate numbers, both machineprecision and arbitraryprecision ones.
  • NumberMarks->Automatic indicates that should be used in arbitraryprecision but not machineprecision numbers.
  • NumberMarks->False indicates that should never be used in outputting numbers.
  • Number marks are used to indicate the type of numbers, and their precision or accuracy.
  • The form for scientific notation is always used in InputForm, and is independent of NumberMarks.

ExamplesExamplesopen allclose all

Basic Examples  (2)Basic Examples  (2)

Machine numbers format without number marks by default:

The same number with number marks:

Extended-precision numbers include number marks by default:

Without number marks:

Introduced in 1996