Greater Than (Image Analyst)

Available with Spatial Analyst license.

Available with Image Analyst license.

Summary

Performs a Relational greater-than operation on two inputs on a cell-by-cell basis.

Returns 1 for cells where the first raster is greater than the second raster and 0 for cells if it is not.

Learn more about how the Relational Math tools work

Illustration

OutRas = GreaterThan(InRas1, 2)

Usage

• Two inputs are necessary for this relational evaluation to take place.

• The order of inputs is relevant for this tool.

• If both inputs are single band rasters, or one of the inputs is a constant, the output will be a single band raster.

• If both inputs are multiband rasters, or one of the inputs is a constant, the output will be a multiband raster. The number of bands in each multiband input must be the same.

• The tool will perform the operation on each band from one input against the corresponding band from the other input. If one of the inputs is a multiband raster and the other input is a constant, the tool will perform the operation against the constant value for each band in the multiband input.

Syntax

GreaterThan(in_raster_or_constant1, in_raster_or_constant2)

Parameter	Explanation	Data Type
in_raster_or_constant1	The input being tested to determine if it is greater than the second input. A number can be used as an input for this parameter, provided a raster is specified for the other parameter. To specify a number for both inputs, the cell size and extent must first be set in the environment.	Raster Layer; Constant
in_raster_or_constant2	The input against which the first input is tested to be greater than. A number can be used as an input for this parameter, provided a raster is specified for the other parameter. To specify a number for both inputs, the cell size and extent must first be set in the environment.	Raster Layer; Constant

Return Value

Name	Explanation	Data Type
out_raster	The output raster. The output cell values will be either integer 0 or 1, or NoData if any input cell value is NoData.	Raster

Code sample

GreaterThan example 1 (Python window)

This example performs a Relational greater-than operation on two Grid rasters and outputs the result as an IMG raster.

import arcpy
from arcpy import env
from arcpy.ia import *
env.workspace = "C:/iapyexamples/data"
outGreaterThan = GreaterThan("degs", "negs")
outGreaterThan.save("C:/iapyexamples/output/outgt.img")

GreaterThan example 2 (stand-alone script)

This example performs a Relational greater-than operation on two Grid rasters.

# Name: GreaterThan_Ex_02.py
# Description: Performs a relational greater-than operation on two inputs
#              on a pixel-by-pixel basis within the Analysis window
# Requirements: Image Analyst Extension

# Import system modules
import arcpy
from arcpy import env
from arcpy.ia import *

# Set environment settings
env.workspace = "C:/iapyexamples/data"

# Set local variables
inRaster1 = "degs"
inRaster2 = "negs"

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

# Execute GreaterThan
outGreaterThan = GreaterThan(inRaster1, inRaster2)

# Save the output 
outGreaterThan.save("C:/iapyexamples/output/outgt")

Environments

Auto Commit, Cell Size, Cell Size Projection Method, Compression, Current Workspace, Extent, Geographic Transformations, Mask, Output CONFIG Keyword, Output Coordinate System, Scratch Workspace, Snap Raster, Tile Size

Licensing information

• Basic: Requires Image Analyst or Spatial Analyst
• Standard: Requires Image Analyst or Spatial Analyst
• Advanced: Requires Image Analyst or Spatial Analyst