Test (Spatial Analyst)

Summary

Performs a Boolean evaluation of the input raster using a logical expression.

When the expression evaluates to true, the output cell value is 1. If the expression is false, the output cell value is 0.

Illustration

Test illustration
OutRas = Test(InRas1,"Value >= 2")

Usage

Syntax

Test (in_raster, where_clause)
ParameterExplanationData Type
in_raster

The input raster on which the Boolean evaluation is performed, based on a logical expression.

Raster Layer
where_clause

A logical expression that selects a subset of raster cells.

The expression follows the general form of an SQL expression.

Consult the documentation for more information on the SQL reference for query expressions used in ArcGIS and specifying a query in Python.

SQL Expression

Return Value

NameExplanationData Type
out_raster

The output raster.

The output values will be either 0 or 1.

Raster

Code Sample

Test example 1 (Python window)

This example uses a Where clause to perform a Boolean operation on an input raster.

import arcpy
from arcpy import env
from arcpy.sa import *
env.workspace = "C:/sapyexamples/data"
outTest = Test("degs", "VALUE > 100")
outTest.save("C:/sapyexamples/output/outest.img")
Test example 2 (stand-alone script)

This example uses a Where clause to perform a Boolean operation on an input raster.

# Name: Test_Ex_02.py
# Description: Perform a Boolean evaluation of the input raster based
#              on a where clause
# Requirements: Spatial Analyst Extension
# Author: ESRI

# 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 = "degs"
inWhereClause = "VALUE > 100"

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

# Execute Test
outTest = Test(inRaster, inWhereClause)

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

Environments

Related Topics

Licensing Information

ArcView: Requires Spatial Analyst
ArcEditor: Requires Spatial Analyst
ArcInfo: Requires Spatial Analyst

6/29/2011