edu.stanford.math.plex4.utility

Class ComparisonUtility

java.lang.Object

edu.stanford.math.plex4.utility.ComparisonUtility

public class ComparisonUtility
extends java.lang.Object

This class contains static methods for comparing various objects.

Author:

Andrew Tausz

Field Summary

Fields

Modifier and Type	Field and Description
static double	HIGH_PRECISION
static double	LOW_PRECISION
static double	MED_PRECISION

Constructor Summary

Constructors

Constructor and Description
ComparisonUtility()

Method Summary

Methods

Modifier and Type	Method and Description
static boolean	compareDoublesAbsolute(double a, double b, double tolerance) This function compares two doubles to see if they are within the specified tolerance of each other.
static boolean	compareDoublesGuardedRelative(double a, double b, double tolerance) This function compares two doubles to see if their (relative/absolute) distance is within the specified tolerance.
static boolean	compareDoublesRelative(double a, double b, double tolerance) This function compares two doubles to see if their relative distance is within the specified tolerance.
static gnu.trove.TIntHashSet	intersect(gnu.trove.TIntHashSet a, gnu.trove.TIntHashSet b) This function computes the intersection of two sets.
static boolean	setEquals(java.util.Collection<?> a, java.util.Collection<?> b) This function returns true if two Collections define the same set; that is they contain the same elements.
static boolean	setEquals(gnu.trove.TIntHashSet a, gnu.trove.TIntHashSet b) This function returns true if the two sets of integers contain the same elements.

Methods inherited from class java.lang.Object

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

Field Detail

LOW_PRECISION

public static final double LOW_PRECISION

See Also:

Constant Field Values

MED_PRECISION

public static final double MED_PRECISION

See Also:

Constant Field Values

HIGH_PRECISION

public static final double HIGH_PRECISION

See Also:

Constant Field Values

Constructor Detail

ComparisonUtility

public ComparisonUtility()

Method Detail

setEquals

public static boolean setEquals(java.util.Collection<?> a,
                java.util.Collection<?> b)

This function returns true if two Collections define the same set; that is they contain the same elements.

Parameters:

a - the first Collection

b - the second Collection

Returns:

true if the two Collections contain the same set of elements.

setEquals

public static boolean setEquals(gnu.trove.TIntHashSet a,
                gnu.trove.TIntHashSet b)

This function returns true if the two sets of integers contain the same elements.

Parameters:

a -

b -

Returns:

true if the two sets are the same

intersect

public static gnu.trove.TIntHashSet intersect(gnu.trove.TIntHashSet a,
                              gnu.trove.TIntHashSet b)

This function computes the intersection of two sets.

Parameters:

a -

b -

Returns:

the set of elements contained in both sets

compareDoublesAbsolute

public static boolean compareDoublesAbsolute(double a,
                             double b,
                             double tolerance)

This function compares two doubles to see if they are within the specified tolerance of each other.

Parameters:

a - the first value

b - the second value

tolerance - the tolerance

Returns:

true iff |a - b| <= tolerance

compareDoublesRelative

public static boolean compareDoublesRelative(double a,
                             double b,
                             double tolerance)

This function compares two doubles to see if their relative distance is within the specified tolerance.

Parameters:

a - the first value

b - the second value

tolerance - the tolerance

Returns:

true iff |a - b| / (0.5 (|a| + |b|)) <= tolerance

compareDoublesGuardedRelative

public static boolean compareDoublesGuardedRelative(double a,
                                    double b,
                                    double tolerance)

This function compares two doubles to see if their (relative/absolute) distance is within the specified tolerance. If 0.5 (|a| + |b|) < 1 it uses an absolute comparison, and otherwise it uses a relative comparison.

Parameters:

a - the first value

b - the second value

tolerance - the tolerance

Returns:

true if the (relative/absolute) distance of a and b is within the given tolerance