| Label | Explanation | Data Type |
Input raster | The input raster to be reclassified. | Raster Layer |
Reclass field | Field denoting the values that will be reclassified. | Field |
Reclassification | A remap table that defines how the values will be reclassified. Working with the table and it options are as follows:
| Remap |
Output raster | The output reclassified raster. The output will always be of integer type. | Raster Dataset |
Change missing values to NoData (Optional) | Denotes whether missing values in the reclass table retain their value or get mapped to NoData.
| Boolean |
Summary
Reclassifies (or changes) the values in a raster.
Usage
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.
In the tool dialog, the Classify or Unique options in the Reclassification parameter allows you to generate a remap table based on the values of the input raster. The Classify option opens a dialog and allow you to specify a method from one of the Data classification methods and number of classes. The Unique option will populate the remap table using the unique values from the input dataset.
It is recommended to calculate statistics on a mosaic dataset before reclassifying the data.
From the tool dialog, the remap table can be stored for future use with the Save option. You can save the remap to any relational table format. Use the Load option to reload remap tables you previously created 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.
If the input raster has an attribute table, it will be used to create the initial reclassification table. If the input raster does not have an attribute table, you can run the Build Raster Attribute Table tool from the Data Management toolbox to build one before inputting the raster into the Reclassify tool. Otherwise, when you input the raster, a reclassification table will be created for it by first applying geoprocessing environment settings, such as Extent and Cell size, and scanning the raster.
When the input raster is a layer from Contents, the default reclassification table will import the unique values or classified break values as specified by the layer symbology. The current geoprocessing environment settings will be ignored when importing those values. Otherwise, the reclassification must be manually entered or generated using the unique or classification options.
Once the remap table of the reclassification has been modified, the table will not be updated if a new input raster is selected. If the reclassification is not suitable for the new raster, a new reclassification can be reinitialized by one of the following methods
- Remove all remap records using the erase option and manually add the new values.
- Select the unique or classification options to generate a new reclassification.
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.
By default, this tool will use multicore processors if available. The maximum number of cores that can be used is four.
To use fewer cores, use the Parallel Processing Factor environment setting.
Parameters
arcpy.ddd.Reclassify(in_raster, reclass_field, remap, out_raster, {missing_values})| Name | Explanation | Data Type |
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.
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" | Remap |
out_raster | The output reclassified raster. The output will always be of integer type. | Raster Dataset |
missing_values (Optional) | Denotes whether missing values in the reclass table retain their value or get mapped to NoData.
| Boolean |
Code sample
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"
# Execute Reclassify
arcpy.ddd.Reclassify(inRaster, field, remapString, outRaster, "DATA")