Reclassify (Spatial Analyst)

Resumen

Reclassifies (or changes) the values in a raster.

Uso

• The input raster must have valid statistics. If the statistics do not exist, they can be created using the Calculate Statistics tool in the Data Management Tools toolbox.

• If using the tool dialog box, the remap table can be stored for future use with the Save button. Use the Load button to open the remap tables you created previously with the Save button.

• It is recommended to only load tables previously saved by the Reclassify tool. The table format is specific and must contain the fields FROM, TO, OUT, and MAPPING.

• By default, the input raster will be classified into nine classes for the reclassification table.

• If the input raster is a layer, the old values of the reclassification will be obtained from the renderer. If the renderer is stretched, the reclassification will default to 255 classes.

• Once the remap table of the reclassification has been modified, the values will not be updated if a new input raster is selected. If the reclassification is not suitable for the new raster, a default reclassification can be reinitialized by:

  • Editing or selecting a new value for the reclass field
  • Restarting the tool

• This tool has a precision control that manages how decimal places are treated.

• When using the Reclassify tool as part of a model:

  • If the input to the tool is derived data from a tool that isn't already run, the remap parameter in the Reclassify tool will be empty until the preceding tool is run and the model is validated. To avoid this, always run preceding tools before connecting their output variables as input to the Reclassify tool. Alternatively, you can create a custom reclassification table by adding entries.
  • If exposing the reclassification table as a model parameter, the reclass field must be exposed as a variable. However, it does not need to be set as a model parameter. If the field is not exposed as a variable, the classify and unique values buttons will be disabled in the model tool dialog box.

Sintaxis

Reclassify (in_raster, reclass_field, remap, {missing_values})

Parámetro	Explicación	Tipo de datos
in_raster	The input raster to be reclassified.	Raster Layer
reclass_field	Field denoting the values that will be reclassified.	Field
remap	The Remap object is used to specify how to reclassify values of the input raster. There are two ways to define how the values will be reclassified in the output raster; RemapRange and RemapValue. Either ranges of input values can be assigned to a new output value, or individual values can be assigned to a new output value. The following are the forms of the remap objects. RemapRange ([[startValue, endValue, newValue],...]) startValue — The lower boundary of the range of values to be assigned a new output value. endValue — The upper boundary of the range of values to be assigned a new output value. newValue — The new value to be assigned to the range of input values defined by the start and end values. RemapValue ([[oldValue, newValue],...]) oldValue — Represents an original value from the base raster. newValue — The new reclassified value.	Remap
missing_values (Opcional)	Denotes whether missing values in the reclass table retain their value or get mapped to NoData. DATA —Signifies that if any cell location on the input raster contains a value that is not present or reclassed in a remap table, the value should remain intact and be written for that location to the output raster. This is the default. NODATA — Signifies that if any cell location on the input raster contains a value that is not present or reclassed in a remap table, the value will be reclassed to NoData for that location on the output raster.	Boolean

Valor de retorno

Nombre	Explicación	Tipo de datos
out_raster	The output reclassified raster. The output will always be of integer type.	Raster

Ejemplo de código

Reclassify example 1 (Python window)

The following examples show several ways of several ways reclassifying a raster.

import arcpy
from arcpy import env  
from arcpy.sa import *
env.workspace = "C:/sapyexamples/data"

outReclass1 = Reclassify("landuse", "Value", 
                         RemapValue([[1,9],[2,8],[3,1],[4,6],[5,3],[6,3],[7,1]]))
outReclass1.save("C:/sapyexamples/output/landuse_rcls")

outReclass2 = Reclassify("slope_grd", "Value", 
                         RemapRange([[0,10,"NODATA"],[10,20,1],[20,30,2],
                                     [30,40,3],[40,50,4],[50,60,5],[60,75,6]]))
outReclass2.save("C:/sapyexamples/output/slope_rcls")

outReclass3 = Reclassify("pop_density", "Value", 
                         RemapRange([[10,10,1],[10,20,2],[20,25,3],
                                     [25,50,4],[50,]]), "NODATA")
outReclass3.save("C:/sapyexamples/output/popden_rcls")

Reclassify example 2 (stand-alone script)

This example reclassifies the input raster based on the values in a string field.

# Name: reclassify_example02.py
# Description: Reclassifies the values in a raster.
# 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 = "landuse"
reclassField = "LANDUSE"
remap = RemapValue([["Brush/transitional", 0], ["Water", 1],["Barren land", 2]])

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

# Execute Reclassify
outReclassify = Reclassify(inRaster, reclassField, remap, "NODATA")

# Save the output 
outReclassify.save("C:/sapyexamples/output/outreclass02")

Entornos

Tamaño de celda, Espacio de trabajo actual, Máscara, Sistema de coordenadas de salida, Extensión, Espacio de trabajo temporal, Alinear ráster

Información de licencia

ArcView: Requiere Spatial Analyst o 3D Analyst

ArcEditor: Requiere Spatial Analyst o 3D Analyst

ArcInfo: Requiere Spatial Analyst o 3D Analyst