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.


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