com.io7m.jequality

Class AlmostEqualDouble

java.lang.Object

com.io7m.jequality.AlmostEqualDouble

@EqualityReference
public final class AlmostEqualDouble
extends Object

Better floating point comparisons.

See Comparing floating point numbers 2012.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	AlmostEqualDouble.ContextRelative The necessary context for floating point comparisons.

Method Summary

Methods

Modifier and Type	Method and Description
static boolean	almostEqual(AlmostEqualDouble.ContextRelative context, double x, double y) Compare the floating point numbers x and y using the context context.

Methods inherited from class java.lang.Object

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

Method Detail

almostEqual

public static boolean almostEqual(AlmostEqualDouble.ContextRelative context,
                  double x,
                  double y)

Compare the floating point numbers x and y using the context context.

Essentially, given diff = abs(x - y), if diff <= context.getMaxRelativeDifference() * max(abs(x), abs(y)) , then x and y can be considered to be close together.

See the article mentioned at the top of this article for suggested absolute and relative epsilon values: There are no values that work well for all possible inputs.

Parameters:

context - The equality context

x - The left parameter

y - The right parameter

Returns:

true if x and y are almost equal