Package org.apache.commons.numbers.core

Interface Precision.DoubleEquivalence

Enclosing class:
Precision
public static interface Precision.DoubleEquivalence
Interface containing comparison operations for doubles that allow values to be considered equal even if they are not exactly equal. It is intended for comparing outputs of a computation where floating point errors may have occurred.

  • Method Summary

    Modifier and Type
    Method
    Description
    int
    compare(double a, double b)
    Compares two values.
    default boolean
    eq(double a, double b)
    Indicates whether given values are considered equal to each other.
    default boolean
    eqZero(double a)
    Indicates whether the given value is considered equal to zero.
    default boolean
    gt(double a, double b)
    Indicates whether the first argument is strictly greater than the second.
    default boolean
    gte(double a, double b)
    Indicates whether the first argument is greater than or considered equal to the second.
    default boolean
    lt(double a, double b)
    Indicates whether the first argument is strictly smaller than the second.
    default boolean
    lte(double a, double b)
    Indicates whether the first argument is smaller or considered equal to the second.
    default double
    signum(double a)
    Returns the sign of the argument.

  • Method Details

    • eq

      default boolean eq(double a, double b)
      Indicates whether given values are considered equal to each other.
      Parameters:
      a - Value.
      b - Value.
      Returns:
      true if the given values are considered equal.

    • eqZero

      default boolean eqZero(double a)
      Indicates whether the given value is considered equal to zero. It is a shortcut for eq(a, 0.0).
      Parameters:
      a - Value.
      Returns:
      true if the argument is considered equal to zero.

    • lt

      default boolean lt(double a, double b)
      Indicates whether the first argument is strictly smaller than the second.
      Parameters:
      a - Value.
      b - Value.
      Returns:
      true if a < b

    • lte

      default boolean lte(double a, double b)
      Indicates whether the first argument is smaller or considered equal to the second.
      Parameters:
      a - Value.
      b - Value.
      Returns:
      true if a <= b

    • gt

      default boolean gt(double a, double b)
      Indicates whether the first argument is strictly greater than the second.
      Parameters:
      a - Value.
      b - Value.
      Returns:
      true if a > b

    • gte

      default boolean gte(double a, double b)
      Indicates whether the first argument is greater than or considered equal to the second.
      Parameters:
      a - Value.
      b - Value.
      Returns:
      true if a >= b

    • signum

      default double signum(double a)
      Returns the sign of the argument. The returned value is
      • -0.0 if a is considered equal to zero and negatively signed,
      • +0.0 if a is considered equal to zero and positively signed,
      • -1.0 if a is considered less than zero,
      • +1.0 if a is considered greater than zero.

      The equality with zero uses the eqZero method.

      Parameters:
      a - Value.
      Returns:
      the sign (or a if a == 0 or a is NaN).
      See Also:

    • compare

      int compare(double a, double b)
      Compares two values. The returned value is
      • 0 if the arguments are considered equal,
      • -1 if a < b,
      • +1 if a > b or if either value is NaN.
      Parameters:
      a - Value.
      b - Value.
      Returns:
      0 if the values are considered equal, -1 if the first is smaller than the second, 1 is the first is larger than the second or either value is NaN.