Negate (Spatial Analyst)

Summary

Changes the sign (multiplies by -1) of the cell values of the input raster on a cell-by-cell basis.

Illustration

OutRas = Negate(InRas1)

Usage

• If the input is integer, the output raster will be integer type. If the input is floating point, the output raster will be floating point.

• In Map Algebra, the equivalent operator symbol for this tool is "-" (link).

Syntax

Negate (in_raster_or_constant)

Parameter	Explanation	Data Type
in_raster_or_constant	The input raster to be negated (multiplied by -1). In order to use a number as an input for this parameter, 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 cell values are the input values negated (multiplied by -1).	Raster

Code Sample

Negate example 1 (Python window)

This example changes the sign of the values in the input raster and outputs a GRID raster.

import arcpy
from arcpy import env
from arcpy.sa import *
env.workspace = "C:/sapyexamples/data"
outNegate = Negate("degs")
outNegate.save("C:/sapyexamples/output/outneg")

Negate example 2 (stand-alone script)

This example changes the sign of the values in the input raster and outputs a GRID raster.

# Name: Negate_Ex_02.py
# Description: Changes the sign (multiplies by -1) of the cell values
#              of the input 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
inRaster = "degs"

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

# Execute Negate
outNegate = Negate(inRaster)

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

Environments

Cell Size, Current Workspace, Mask, Output Coordinate System, Extent, Scratch Workspace, Snap Raster

Licensing Information

ArcGIS for Desktop Basic: Requires Spatial Analyst

ArcGIS for Desktop Standard: Requires Spatial Analyst

ArcGIS for Desktop Advanced: Requires Spatial Analyst