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IClassify Interface (ArcObjects .NET 10.8 SDK)
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IClassify Interface

Provides access to members that control the classification methods.

Product Availability

Available with ArcGIS Engine, ArcGIS Desktop, and ArcGIS Server.


Classify objects apply one of several methods to statistically subdivide a set of numeric values into classes.

The IClassify interface is implemented by all the data classification objects (DefinedInterval, EqualInterval, NaturalBreaks, Quantile, StandardDeviation); this is the interface used to pass in histogram data and then classify it into breaks. The ClassID and MethodName properties are used by user interface dialog boxes to identify the classification object and establish what the classification is called.

In general, to classify a dataset, use this interface together with IClassBreaksRenderer.  First, add data to the classification using  SetHistogramData.  Next, set the number of classes and generate breaks using Classify (typically use the same number of classes specified here for IClassBreaksRenderer.BreakCount). Then apply the classification to the renderer by cycling through ClassBreaks and setting each IClassBreaksRenderer.Break.


Name Description
Read-only property ClassBreaks The array of class breaks (double). ClassBreaks(0) is the minimum value in the dataset, and subsequent breaks represent the upper limit of each class.
Read-only property ClassID The CLSID for the classification object.
Method Classify Classifies data into the specified number of classes.
Read-only property MethodName The name of the classification method (based on choice of classification object).
Method SetHistogramData Adds data in form of a histogram (array of values (doubles) and a paired array of frequencies (longs)) to the classification.

Classes that implement IClassify

Classes Description
DefinedInterval Defines a defined interval classification method.
EqualInterval Defines an equal interval classification method.
GeometricalInterval Defines a geometrical interval classification method.
NaturalBreaks Defines a natural breaks classification method.
Quantile Defines a quantile classification method.
StandardDeviation Defines a standard deviation classification method.


Do not call IClassify.Classify for a StandardDeviation classification until you have set deviation properties using IDeviationInterval.

Instead of IClassify interface, implement IClassifyGEN interface that has been created to replace this one.

See Also

ClassBreaksRenderer Class | DefinedInterval Class | StandardDeviation Class | NaturalBreaks Class | Quantile Class | EqualInterval Class