ArcObjects Library Reference (SpatialAnalyst)  

IHydrologyOp.StreamOrder Method

Assigns a numeric order to segments of a raster representing branches of a linear network.

[Visual Basic .NET]
Public Function StreamOrder ( _
    ByVal streamRaster As IGeoDataset, _
    ByVal directionRaster As IGeoDataset, _
    ByVal orderType As esriGeoAnalysisStreamOrderEnum _
) As IGeoDataset
[C#]
public IGeoDataset StreamOrder (
    IGeoDataset streamRaster,
    IGeoDataset directionRaster,
    esriGeoAnalysisStreamOrderEnum orderType
);
[C++]
HRESULT StreamOrder(
  IGeoDataset* streamRaster,
  IGeoDataset* directionRaster,
  esriGeoAnalysisStreamOrderEnum orderType,
  IGeoDataset** StreamOrder
);
[C++]

Parameters

streamRaster [in]

  streamRaster is a parameter of type IGeoDataset

directionRaster [in]

  directionRaster is a parameter of type IGeoDataset

orderType [in]

  orderType is a parameter of type esriGeoAnalysisStreamOrderEnum

StreamOrder [out, retval]

  StreamOrder is a parameter of type IGeoDataset

Product Availability

Available with ArcGIS Engine, ArcGIS Desktop, and ArcGIS Server. Requires Spatial Analyst Extension.

Remarks

streamRaster

an input Raster, RasterDataset, RasterBand, or RasterDescriptor representing a raster linear network

directionRaster

an input Raster, RasterDataset, RasterBand, or RasterDescriptor showing the direction of flow out of each cell

This can be created using the IHydrologyOp::FlowDirection method.

orderType

an esriGeoAnalysisStreamOrderEnum indicating the method for assigning order

esriGeoAnalysisStreamOrderStrahler the method will be the stream ordering proposed by Strahler in 1952

Stream order only increases when streams of the same order intersect. Therefore, the intersection of a first-order and second-order link will remain a second-order link rather than create a third-order link. This method is commonly used.

esriGeoAnalysisStreamOrderShreve the method will be stream ordering by magnitude proposed by Shreve in 1967

All links with no tributaries are assigned a magnitude (order) of 1. Magnitudes are additive downslope. When two links intersect, their magnitudes are added and assigned to the downslope link.

 

See Also

IHydrologyOp Interface