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Stream Link

Available with Spatial Analyst license.

Summary

Assigns unique values to sections of a raster linear network between intersections.

Illustration

Stream Link tool illustration

Usage

  • Links are the sections of a stream channel connecting two successive junctions, a junction and the outlet, or a junction and the drainage divide.

    Links in a stream channel illustration
    Illustration of the links in a stream channel

  • The input stream raster can be created by thresholding the results of the Flow Accumulation tool.

  • The stream raster linear network should be represented as values greater than or equal to one on a background of NoData.

  • The Stream Link tool only supports a D8 input flow direction raster. D8 flow directions can be created using the Flow Direction tool, run with default flow direction type D8.

  • See Analysis environments and Spatial Analyst for additional details on the geoprocessing environments that apply to this tool.

Syntax

StreamLink (in_stream_raster, in_flow_direction_raster)
ParameterExplanationData Type
in_stream_raster

An input raster that represents a linear stream network.

Raster Layer
in_flow_direction_raster

The input raster that shows the direction of flow out of each cell.

The flow direction raster can be created using the Flow Direction tool, run using the default flow direction type D8.

Raster Layer

Return Value

NameExplanationData Type
out_raster

The output stream link raster.

This output is of integer type.

Raster

Code sample

StreamLink example 1 (Python window)

This example assigns unique values to sections of a raster linear network between intersections.

import arcpy
from arcpy import env
from arcpy.sa import *
env.workspace = "C:/sapyexamples/data"
outStreamLink = StreamLink("stream", "flowdir")
outStreamLink.save("c:/sapyexamples/output/outstrmlnk01")
StreamLink example 2 (stand-alone script)

This example assigns unique values to sections of a raster linear network between intersections.

# Name: _Ex_02.py
# Description: 
# Requirements: Spatial Analyst Extension

# Import system modules
import arcpy
from arcpy import env
from arcpy.sa import *

# Set environment settings
env.workspace = "C:/sapyexamples/data"

# Set local variables
inStreamRaster = "stream"
inFlowDirection = "flowdir"

# Execute StreamLink
outStreamLink = StreamLink(inStreamRaster, inFlowDirection)

# Save the output 
outStreamLink.save("c:/sapyexamples/output/outstrmlnk02")

Licensing information

  • ArcGIS Desktop Basic: Requires Spatial Analyst
  • ArcGIS Desktop Standard: Requires Spatial Analyst
  • ArcGIS Desktop Advanced: Requires Spatial Analyst

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