* (Multiplication) (arcpy.sa)

Summary

Multiplies the values of two rasters on a cell-by-cell basis.

Illustration

Times illustration
OutRas = Raster("InRas1") * Raster("InRas2")

Discussion

When using an operator with a raster input the result will be a raster. However, if all inputs are numbers, then the result is a number.

When multiple operators are used in an expression, they are not necessarily executed in left-to-right order. The operator with the highest precedence value will be executed first. For more information on operator precedence, see operator precedence table. You can use parentheses to control the execution order.

The order of input is irrelevant for this operator.

If both input values are integers, the output values will be integers; otherwise, the output will be floating-point values.

Syntax

in_raster_or_constant1 * in_raster_or_constant2
OperandExplanationData Type
in_raster_or_constant1

The input containing the values to be multiplied.

If one of the inputs is a raster and the other is a scalar, an output raster is created with each cell in the input raster being multiplied by the scalar.

Raster Layer | Constant
in_raster_or_constant2

The input containing the values by which the first input will be multiplied.

If one of the inputs is a raster and the other is a scalar, an output raster is created with each cell in the input raster being multiplied by the scalar.

Raster Layer | Constant

Return Value

NameExplanationData Type
out_raster

The output raster object.

The cell values are the product of the first input multiplied by the second.

Raster

Code Sample

* (Multiplication) example 1 (Python window)

This sample multiplies the values of an input elevation raster by a constant value to convert the elevation values from meters to feet.

import arcpy
from arcpy import env
from arcpy.sa import *
env.workspace = "C:/sapyexamples/data"
outTimes = Raster("elevation") * 0.3048
outTimes.save("C:/sapyexamples/output/outtimes")
* (Multiplication) example 2 (stand-alone script)

This sample multiplies the values of an input elevation raster by a constant value to convert the elevation values from meters to feet.

# Name: Op_Times_Ex_02.py
# Description: Multiplies the values of two rasters 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 = Raster("elevation")
inConstant = 0.3048

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

# Execute Times
outTimes = inRaster * inConstant

# Save the output 
outTimes.save("C:/sapyexamples/output/timesout")

Environments

Related Topics

7/16/2013