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 Documentation / Mathematica / Built-in Functions / New in Version 3.0 / Numerical Computation  /

  • FractionalPart[ x ] gives the fractional part of x.
  • Mathematical function (see Section A.3.10).
  • FractionalPart[ x ] in effect takes all digits to the right of the decimal point and drops the others.
  • Examples: FractionalPart[2.4]; FractionalPart[2.6]; FractionalPart[-2.4]; FractionalPart[-2.6].
  • FractionalPart[ x ] + IntegerPart[ x ] is always exactly x.
  • FractionalPart[ x ] yields a result when x is any numeric quantity, whether or not it is an explicit number.
  • Example: FractionalPart[Pi^2].
  • For exact numeric quantities, FractionalPart internally uses numerical approximations to establish its result. This process can be affected by the setting of the global variable $MaxExtraPrecision.
  • See the Mathematica book: Section 3.2.2.
  • See also: IntegerPart, Mod.