Reclassify (3D Analyst)
Reclassifies (or changes) the values in a raster.
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 a range of values is to be reclassed, the ranges should not overlap except at the boundary of two input ranges. Where overlapping occurs, the higher end of the lower input range is inclusive, and the lower end of the higher input range is exclusive.
For example, if two ranges are specified, such as reclassifying values 1 to 5 as 100 and values 5 to 10 as 200, an input value less than or equal to 5 will be assigned the value 100 in the output, and an input value that is larger than 5, such as 5.01, will be assigned to 200.
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.
The input raster to be reclassified.
Field denoting the values that will be reclassified.
A remap list that defines how the values will be reclassified.
The remap list is composed of three components: From, To, and New values. Each row in the remap list is separated by a semicolon, and the three components are separated by spaces. For example:
"0 5 1;5.01 7.5 2;7.5 10 3"
The output reclassified raster.
The output will always be of integer type.
Denotes whether missing values in the reclass table retain their value or get mapped to NoData.
The following example shows how to reclassify a raster into seven classes.
import arcpy from arcpy import env env.workspace = "C:/sapyexamples/data" arcpy.Reclassify_3d("C:/data/landuse", "VALUE", "1 9;2 8;3 1;4 6;5 3;6 2;7 1", "C:/output/outremap","DATA")
This example reclassifies the input raster based on the values in a string field.
# Name: Reclassify_3d_Ex_02.py # Description: Reclassifies the values in a raster. # Requirements: 3D Analyst Extension # Import system modules import arcpy from arcpy import env # Set environment settings env.workspace = "C:/data" # Set local variables inRaster = "landuse" field = "VALUE" remapString = "1 9;2 8;3 1;4 6;5 3;6 2;7 1" outRaster = "C:/output/reclass3d" # Check out the ArcGIS 3D Analyst extension license arcpy.CheckOutExtension("3D") # Execute Reclassify arcpy.Reclassify_3d(inRaster, field, remapString, outRaster, "DATA")