RemapValue (arcpy.sa)

Summary

A list identifying what the individual input values should be reclassified to in an output raster.

Illustration

RemapValue remap table for the Reclassify functions.

Discussion

The RemapValue object can be used in the Reclassify tool and the WOTable class.

The oldValue can be assigned to NoData by entering NoData (a string) as the newValue.

Reclassifying individual values is usually done when the input values are categorical, for example, land use, or when changing only a few values.

Syntax

RemapValue (remapTable)

Parameter	Explanation	Data Type
remapTable [[oldValue, newValue],...]	The remap table to be used to remap the old values to new values. It defines a list to be used to remap the input values. It is a list of lists, with the inner lists being composed of two components. The components are: oldValue—Represents an original value from the base raster (data type: double, long, string). newValue—Is the new reclassified value (data type: long). The oldValue can be numeric or string. The newValue must be integer.	List

Properties

Property	Explanation	Data Type
remapTable (Read and Write)	The remap table that is used to remap the original values to new values.	List

Code Sample

RemapValue example 1 (Python window)

Demonstrates how to create a RemapValue class and use it in the Reclassify tool within the Python window.

import arcpy
from arcpy import env
from arcpy.sa import *
env.workspace = "C:/sapyexamples/data"
myRemapValue = RemapValue([["Water", 0], ["Wetlands", 0], ["Barrenland", 1], ["Brushtransitional", 2], ["Builtup",3]])
outReclassRV = Reclassify("landuse", "LANDUSE2", myRemapValue)
outReclassRV.save("C:/sapyexamples/output/reclassrv")

RemapValue example 2 (stand-alone script)

Performs a reclassification with the RemapValue class.

# Name: RemapValue_Ex_02.py
# Description: Uses the RemapValue object to execute Reclassify tool.
# 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
inRaster = "negs"

# Define the RemapValue Object
myRemapVal = RemapValue([[-3,9],[0,1],[3,-4],[4,5],[5,6],[6,4],[7,-7]])

# Check out the ArcGIS Spatial Analyst extension license
arcpy.CheckOutExtension("Spatial")

# Execute Reclassify
outReclassRV = Reclassify(inRaster, "VALUE", myRemapVal, "")

# Save the output 
outReclassRV.save("C:/sapyexamples/output/reclassrevar2")