org.apache.commons.geometry.core.precision

Class DoublePrecisionContext

java.lang.Object

org.apache.commons.geometry.core.precision.DoublePrecisionContext

All Implemented Interfaces:

Comparator<Double>

Direct Known Subclasses:

EpsilonDoublePrecisionContext

public abstract class DoublePrecisionContext
extends Object
implements Comparator<Double>

Class encapsulating the concept of comparison operations for doubles.

Constructor Summary

Constructors

Constructor and Description
DoublePrecisionContext()

Method Summary

Modifier and Type	Method and Description
abstract int	compare(double a, double b) Compare two double values.
int	compare(Double a, Double b)
boolean	eq(double a, double b) Return true if the given values are considered equal to each other.
boolean	eqZero(double n) Return true if the given value is considered equal to zero.
abstract double	getMaxZero() Get the largest positive double value that is still considered equal to zero by this instance.
boolean	gt(double a, double b) Return true if the first argument is strictly greater than the second.
boolean	gte(double a, double b) Return true if the first argument is greater than or equal to the second.
boolean	lt(double a, double b) Return true if the first argument is strictly less than the second.
boolean	lte(double a, double b) Return true if the first argument is less than or equal to the second.
int	sign(double a) Return the sign of the argument: 0 if the value is considered equal to zero, -1 if less than 0, and +1 if greater than 0.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface java.util.Comparator

comparing, comparing, comparingDouble, comparingInt, comparingLong, equals, naturalOrder, nullsFirst, nullsLast, reversed, reverseOrder, thenComparing, thenComparing, thenComparing, thenComparingDouble, thenComparingInt, thenComparingLong

Constructor Detail

DoublePrecisionContext

public DoublePrecisionContext()

Method Detail

eq

public boolean eq(double a,
                  double b)

Return true if the given values are considered equal to each other.

Parameters:

a - first value

b - second value

Returns:

true if the given values are considered equal

eqZero

public boolean eqZero(double n)

Return true if the given value is considered equal to zero. This is equivalent context.eq(n, 0.0) but with a more explicit method name.

Parameters:

n - the number to compare to zero

Returns:

true if the argument is considered equal to zero.

lt

public boolean lt(double a,
                  double b)

Return true if the first argument is strictly less than the second.

Parameters:

a - first value

b - second value

Returns:

true if a < b

lte

public boolean lte(double a,
                   double b)

Return true if the first argument is less than or equal to the second.

Parameters:

a - first value

b - second value

Returns:

true if a <= b

gt

public boolean gt(double a,
                  double b)

Return true if the first argument is strictly greater than the second.

Parameters:

a - first value

b - second value

Returns:

true if a > b

gte

public boolean gte(double a,
                   double b)

Return true if the first argument is greater than or equal to the second.

Parameters:

a - first value

b - second value

Returns:

true if a >= b

sign

public int sign(double a)

Return the sign of the argument: 0 if the value is considered equal to zero, -1 if less than 0, and +1 if greater than 0.

Parameters:

a - number to determine the sign of

Returns:

0 if the number is considered equal to 0, -1 if less than 0, and +1 if greater than 0

compare

public int compare(Double a,
                   Double b)

Specified by:

compare in interface Comparator<Double>

compare

public abstract int compare(double a,
                            double b)

Compare two double 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 - first value

b - second 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.

getMaxZero

public abstract double getMaxZero()

Get the largest positive double value that is still considered equal to zero by this instance.

Returns:

the largest positive double value still considered equal to zero