Package org.geotools.filter.function

Class EqualAreaFunction

Object

ExpressionAbstract

DefaultExpression

ClassificationFunction

AbstractQuantityClassificationFunction

EqualAreaFunction

All Implemented Interfaces:

Expression, Function, FunctionExpression, Factory

public class EqualAreaFunction
extends AbstractQuantityClassificationFunction

Breaks a SimpleFeatureCollection into classes with (roughtly) equal total items area in each class

Author:

Andrea Aime - GeoSolutions

Field Summary

Fields

Modifier and Type	Field	Description
static FunctionName	NAME

Fields inherited from class ClassificationFunction

LOGGER

Fields inherited from interface Expression

NIL

Constructor Summary

Constructors

Constructor	Description
EqualAreaFunction()

Method Summary

Modifier and Type	Method	Description
static Function	getCartesianAreaFunction()	The default area is computed as a cartesian area of the data (will work reasonably on geodetic dataset over small areas, but won't work properly over large areas) However, it is to be remembered that these classification functions are trying to get a certain evennes on the display, so if the display is in plate caree, then computing area over lon/lat is actually the right thing to do.
protected FeatureCalc	getListVisitor()	Returns the list visitor for the specific implementation of "quantity" (e.g., count, area, ...).
protected boolean	percentages()

Methods inherited from class AbstractQuantityClassificationFunction

evaluate

Methods inherited from class ClassificationFunction

accept, computeGroupByPercentages, computePercentage, decimalPlaces, fixRound, getClasses, getFallbackValue, getFunctionName, getImplementationHints, getName, getParameters, getProgressListener, round, setClasses, setFallbackValue, setParameters, setProgressListener, toString

Methods inherited from class DefaultExpression

isAttributeExpression, isExpression, isFunctionExpression, isGeometryExpression, isLiteralExpression, isMathExpression

Methods inherited from class ExpressionAbstract

evaluate

Methods inherited from class Object

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

Methods inherited from interface Expression

evaluate

Field Details

NAME

public static FunctionName NAME

Constructor Details

EqualAreaFunction

public EqualAreaFunction()

Method Details

getCartesianAreaFunction

public static Function getCartesianAreaFunction()

The default area is computed as a cartesian area of the data (will work reasonably on geodetic dataset over small areas, but won't work properly over large areas) However, it is to be remembered that these classification functions are trying to get a certain evennes on the display, so if the display is in plate caree, then computing area over lon/lat is actually the right thing to do.

getListVisitor

protected FeatureCalc getListVisitor()

Description copied from class: AbstractQuantityClassificationFunction

Returns the list visitor for the specific implementation of "quantity" (e.g., count, area, ...). The visitor must return a "bins" structure matching {code}List[]{code}, where each array entry is a bin, and values inside the bin are sorted from lowest to highest

Specified by:

getListVisitor in class AbstractQuantityClassificationFunction

percentages

protected boolean percentages()

Specified by:

percentages in class AbstractQuantityClassificationFunction

Returns:

true if percentages computation is enabled, false if not