6.38.8  Converting a number into an interval: convert

The convert command (see Section 6.23.26) can convert an expression which evaluates to a number to the smallest interval which contains the number.

• convert takes two mandatory arguments and one optional argument:
  • expr, a number which evaluates to a number.
  • interval, a reserved word.
  • Optionally, n, an integer greater than 15 giving the desired number of digits.
• convert(expr,interval  ⟨,n⟩) returns the smallest interval containing the value of expr.

Examples.

• Input:
  convert(sin(3)+1, interval)
  Output:

  [1.14112000805985..1.14112000805990]

• Input:
  convert(sin(3)+1, interval,20)
  Output:

  [1.1411200080598672220..1.1411200080598672222]