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RealDigits

  • RealDigits[ x ] gives a list of the digits in the approximate real number x, together with the number of digits that are to the left of the decimal point.
  • RealDigits[ x , b ] gives a list of base-b digits in x.
  • RealDigits[ x , b , len ] gives a list of len digits.
  • RealDigits[ x , b , len , n ] gives len digits starting with the coefficient of .
  • RealDigits[ x ] returns a list of digits whose length is equal to Precision[ x ].
  • RealDigits[ x ] and RealDigits[ x , b ] require that x be an approximate real number, returned for example by N. RealDigits[ x , b , len ] also works on exact numbers.
  • If len is larger than Log[10, b ] Precision[ x ] remaining digits are filled in as Indeterminate.
  • RealDigits[ x , b , len , n ] starts with the digit which is the coefficient of , truncating or padding with zeros as necessary.
  • RealDigits[ x , b , len , -1] starts with the digit immediately to the right of the base b decimal point in x.
  • The base b in RealDigits[ x , b ] need not be an integer. For any real b such that , RealDigits[ x , b ] successively finds the largest integer multiples of powers of b that can be removed while leaving a non-negative remainder.
  • RealDigits[ x ] discards the sign of x.
  • FromDigits can be used as the inverse of RealDigits.
  • See the Mathematica book: Section 3.1.3.
  • See also: MantissaExponent, IntegerDigits, BaseForm, FromDigits.

    Further Examples

    The second input gives the digits in an approximation to .

    In[1]:=

    Out[1]=

    In[2]:=

    Out[2]=

    Similarly these are digits in base .

    In[3]:=

    Out[3]=

    In[4]:=

    Out[4]=