Test (Image Analyst Tools)

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

Usage

The test is specified by an SQL expression in the Where clause.
The Where clause uses an SQL query. See the following topics for more details on creating queries:
- Build an SQL query
- SQL reference for query expressions used in ArcGIS
In order to use a {where_clause} in Python, it should be enclosed in quotes. For example, "Value > 5000".

You can consult the help for more information on specifying a query in Python.
If the input is a multiband raster, the output will be a multiband raster. The tool will perform the operation on each band in the input.
If the input is multidimensional raster data, all slices from all variables will be processed. The output will be a multidimensional raster in CRF format.

Label	Explanation	Data type
Input raster	The input raster on which the Boolean evaluation is performed, based on a logical expression.	Raster Layer
Where clause	The logical expression that will determine which input cells will return a value of true (1) and which will be false (0). The Where clause follows the general form of an SQL expression. It can be entered directly, for example, VALUE > 100, if you click the Edit SQL mode button . If in the Edit Clause Mode , you can begin constructing the expression by clicking on the Add Clause Mode button.	SQL Expression

Label

Explanation

Data type

Input raster

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

Raster Layer

Where clause

The logical expression that will determine which input cells will return a value of true (1) and which will be false (0).

The Where clause follows the general form of an SQL expression. It can be entered directly, for example, VALUE > 100, if you click the Edit SQL mode button . If in the Edit Clause Mode , you can begin constructing the expression by clicking on the Add Clause Mode button.

SQL Expression

Return value

Label	Explanation	Data type
Output raster	The output raster. The output cell values will be either 0 or 1.	Raster

Label

Explanation

Data type

Output raster

The output raster.

The output cell values will be either 0 or 1.

Raster

Test(in_raster, where_clause)

Name Explanation Data type

Name	Explanation	Data type
in_raster	The input raster on which the Boolean evaluation is performed, based on a logical expression.	Raster Layer
where_clause	The logical expression that will determine which input cells will return a value of true (1) and which will be false (0). The expression follows the general form of an SQL expression. An example of a `where_clause` is "VALUE > 100".	SQL Expression

in_raster

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

Raster Layer

where_clause

The logical expression that will determine which input cells will return a value of true (1) and which will be false (0).

The expression follows the general form of an SQL expression. An example of a where_clause is "VALUE > 100".

SQL Expression

Return value

Name	Explanation	Data type
out_raster	The output raster. The output cell values will be either 0 or 1.	Raster

Name

Explanation

Data type

out_raster

The output raster.

The output cell 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.ia import *
env.workspace = "C:/iapyexamples/data"
outTest = Test("degs", "VALUE > 100")
outTest.save("C:/iapyexamples/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: 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
inRaster = "degs"
inWhereClause = "VALUE > 100"

# Run Test
outTest = Test(inRaster, inWhereClause)

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

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

Test (Image Analyst Tools)

Summary

Illustration

Usage

Parameters

Return value

Environments

Licensing information

Related topics