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IDataSampling Interface (ArcObjects .NET 10.8 SDK)
ArcObjects Help for .NET developers > ArcObjects Help for .NET developers > ArcObjects namespaces > Carto > ESRI.ArcGIS.Carto > Interfaces > ID > IDataSampling Interface
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IDataSampling Interface

Provides access to members that control the data sampling properties of a renderer.

Product Availability

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


Name Description
Read/write property MaxSampleSize Maximum sample size.
Read/write property SamplingMethod Data sampling method.

Classes that implement IDataSampling

Classes Description
ClassBreaksRenderer A renderer that can be used to draw graduated color (choropleth) and graduated symbol maps.
LasPointElevationRenderer LasDataset point renderer component.
TerrainPointAttributeRenderer Terrain point renderer component.
TerrainPointElevationRenderer Terrain point renderer component.
TinAspectRenderer TIN aspect renderer component.
TinElevationRenderer TIN elevation renderer component.
TinNodeElevationRenderer TIN node elevation renderer component.
TinSlopeRenderer TIN slope renderer component.


Use this interface to classify data for symbolization based on a subset of features instead of by considering all feature values. More specically, use this interface to specify the maximum number of features to consider when generating class breaks from a classification object.

To perform data sampling using this interface, first instantiate a renderer and set IDataSampling::MaxSampleSize. Next, pass this renderer to a TableHistogram or BasicTableHistogram using ITableHistogram::Sampling. Use IHistogram::GetHistogram to generate a list pair of values and frequencies. Then, classify your data using IClassifyGEN::Classify, passing these lists as parameters. Finally, take the class breaks that were generated by this operation and assign them to your renderer. For example, if working with a ClassBreaksRenderer, set your breaks using IClassBreaksRenderer::Break.

You can also use this interface to check to see if data sampling was used to generate the class breaks for an existing renderer. This works only if the renderer has been assigned by using the standard ArcMap user interface.