Skip To Content

Equal To Frequency

Available with Spatial Analyst license.

Summary

Evaluates on a cell-by-cell basis the number of times the values in a set of rasters are equal to another raster.

Illustration

Equal To Frequency illustration
OutRas = EqualToFrequency(ValRas, [InRas1, InRas2, InRas3])

Usage

  • An arbitrary number of rasters can be specified in the input rasters list.

  • If a cell location contains NoData on any of the input rasters, that location will be assigned NoData on the output.

  • The output raster is always of integer type.

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

Syntax

EqualToFrequency (in_value_raster, in_rasters)
ParameterExplanationData Type
in_value_raster

For each cell location in the input value raster, the number of occurrences (frequency) where a raster in the input list has an equal value is counted.

Raster Layer
in_rasters
[in_raster,...]

The list of rasters that will be compared against the value raster.

Raster Layer

Return Value

NameExplanationData Type
out_raster

The output raster.

For each cell in the output raster, the value represents the number of times that the corresponding cells in the list of rasters are the same as the value raster.

Raster

Code sample

EqualToFrequency example 1 (Python window)

This example evaluates the number of times a set of input rasters is equal to another raster and outputs the result as a TIFF raster.

import arcpy
from arcpy import env
from arcpy.sa import *
env.workspace = "C:/sapyexamples/data"
outETF = EqualToFrequency("cost", ["degs", "negs", "fourgrd"])
outETF.save("C:/sapyexamples/output/outetf.tif")
EqualToFrequency example 2 (stand-alone script)

This example evaluates the number of times a set of input rasters is equal to another raster and outputs the result as a Grid raster.

# Name: EqualToFrequency_Ex_02.py
# Description: Evaluates the number of times a set of rasters is
#              equal to another raster on a cell-by-cell basis
# 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
inValueRaster = "cost"
inRaster01 = "degs"
inRaster02 = "negs"
inRaster03 = "fourgrd"

# Execute EqualToFrequency
outETF = EqualToFrequency(inValueRaster, [inRaster01, inRaster02, inRaster03])

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

Licensing information

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

Related topics