BUILT-IN MATHEMATICA SYMBOL

# FromDigits

FromDigits[list]
constructs an integer from the list of its decimal digits.

FromDigits[list, b]
takes the digits to be given in base b.

FromDigits["string"]
constructs an integer from a string of digits.

FromDigits["string", "Roman"]
constructs an integer from Roman numerals.

## DetailsDetails

• FromDigits is effectively the inverse of IntegerDigits and IntegerString.
• FromDigits[{list, n}, b] takes n to be an exponent, while FromDigits[{{a1, a2, ..., {rep}}, n}, b] takes rep to be repeated, so that FromDigits can also be used as the inverse of RealDigits.
• Since discards the sign of n, is Abs[n] not just n. »
• The digits in list and the base b need not be positive integers, and can be any expression. »
• If Indeterminate appears in list, it is assumed to signify unknown digits beyond the precision of an approximate real number. »
• FromDigits["string", b] takes the digits in to be given in base b.
• In FromDigits["string", b], digits above 9 can be represented by letters - or -.

## ExamplesExamplesopen allclose all

### Basic Examples (2)Basic Examples (2)

Construct a number from its base-10 digits:

 Out[1]=

Base-2 digits:

 Out[1]=