* (Multiplication) operator

Available with Spatial Analyst license.

Available with Image Analyst license.

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, 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, see the operator precedence table in Work with operators in Map Algebra. You can use parentheses to control the execution order.

The order of the 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.

If both inputs are single-band rasters, or one of the inputs is a constant, the output will be a single-band raster.

If both inputs are multiband rasters, the operator will perform the operation on each band from one input, and the output will be a multiband raster. The number of bands in each multiband input must be the same.

If one of the inputs is a multiband raster and the other input is a constant, the operator will perform the operation against the constant value for each band in the multiband input, and the output will be a multiband raster.

If both inputs are multidimensional rasters with same number of variables, the operator will perform the operation for all slices with same dimension value, and the output will be a multidimensional raster. The variables in the inputs must have same dimensions or common dimension but no uncommon dimensions.

If both inputs have one variable but different names, set the matchMultidimensionalVariable geoprocessing environment to False to perform the operation.

If one of the inputs is a multidimensional raster and the other input is a constant, the operator will perform the operation for all slices for all variables against the constant value, and the output will be a multidimensional raster.

Parameters

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

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

# Execute Times
outTimes = inRaster * inConstant

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

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