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Is Null

Available with Spatial Analyst license.

Available with Image Analyst license.

Summary

Determines which values from the input raster are NoData on a cell-by-cell basis.

Returns a value of 1 if the input value is NoData and 0 for cells that are not.

Illustration

Is Null illustration
OutRas = IsNull(InRas1)

Usage

Syntax

IsNull (in_raster)
ParameterExplanationData Type
in_raster

The input raster being tested to identify the cells that are NoData (null).

The input can be either integer or floating-point type.

Raster Layer

Return Value

NameExplanationData Type
out_raster

The output raster.

The output identifies with an integer value of 1 which cells in the input are NoData. If the input is any other value, the output is 0.

Raster

Code sample

IsNull example 1 (Python window)

This example identifies which cells in the input raster are NoData, and outputs the result as an IMG raster.

import arcpy
from arcpy import env
from arcpy.sa import *
env.workspace = "C:/sapyexamples/data"
outIsNull = IsNull("degs")
outIsNull.save("C:/sapyexamples/output/outisnull.img")
IsNull example 2 (stand-alone script)

This example identifies which cells in the input raster are NoData, and outputs the result as a Grid raster.

# Name: IsNull_Ex_02.py
# Description: Find which cell values of the input raster are NoData
# 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
inRaster = "degs"

# Execute IsNull
outIsNull = IsNull(inRaster)

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

Licensing information

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

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