Interface Number

All Superinterfaces:
Comparable<Number>
All Known Subinterfaces:
IntegerNumber, RationalNumber

public interface Number extends Comparable<Number>
A number is some kind of representation of a real number. Integer numbers and rational numbers live in two different universes, so are never equal. The natural comparison places some arbitrary order on Numbers consistent with equals.
  • Method Summary

    Modifier and Type
    Method
    Description
    The string representation used when this number appears inside of another expression.
    boolean
    Is this number infinite?
    boolean
    Is this number equal to 1?
    boolean
    Is this number equal to 0? Same as signum() == 0, but sometimes more convenient.
    int
    This is a numerical comparison, so the order is a numerical order based on the value of this and other.
    int
    Returns 0 if this number equals 0, -1 if this number is negative, 1 if this number is positive.

    Methods inherited from interface java.lang.Comparable

    compareTo
  • Method Details

    • signum

      int signum()
      Returns 0 if this number equals 0, -1 if this number is negative, 1 if this number is positive.
    • isZero

      boolean isZero()
      Is this number equal to 0? Same as signum() == 0, but sometimes more convenient.
    • isOne

      boolean isOne()
      Is this number equal to 1?
    • isInfinite

      boolean isInfinite()
      Is this number infinite?
      Returns:
      true, if it is positive/negative infinity;
      false, if it is finite.
    • atomString

      String atomString()
      The string representation used when this number appears inside of another expression. For example if the number is 3/4, this method could return (3/4), because in the expression 10*(3/4) you really need the parentheses. On the other hand, if the representation is 0.75, the parens probably are not necessary, and this method might return the same thing as the toString() method.
    • numericalCompareTo

      int numericalCompareTo(Number other)
      This is a numerical comparison, so the order is a numerical order based on the value of this and other.
      Parameters:
      other - a non-null Number with the same type with this.
      Returns:
      Returns a positive value if this is greater than other, 0 if this equals other, a negative value if this is less than other.