# RasterCalculator

Disponible avec une licence Image Analyst.

Disponible avec une licence Spatial Analyst.

## Synthèse

Provides access to all existing math functions and returns a raster object with the mathematical operation applied.

## Discussion

The referenced raster dataset for the raster object is temporary. To make it permanent, you can call the raster object's save method.

## Syntaxe

`RasterCalculator (rasters, input_names, expression, {extent_type}, {cellsize_type})`
 Paramètre Explication Type de données rasters[rasters,...] The list of input rasters. Raster input_names[input_names,...] The user-defined variable names. String expression Build an algebraic expression to perform spatial analysis on the input raster. String extent_type The spatial extent used to create the output raster.FirstOf—The extent of the first raster variableIntersectionOf—The minimum area common to all input rastersUnionOf—The combined extent of all input rastersLastOf—The extent of the last raster variable(La valeur par défaut est FirstOf) String cellsize_type The cell size used to create the output raster.FirstOf—The cell size of the first raster variableMinOf—The minimum cell size of the input rastersMaxOf—The maximum cell size of the input rastersMeanOf—The average cell size of the input rastersLastOf—The cell size of the last raster variable(La valeur par défaut est FirstOf) String
Valeur renvoyée
 Type de données Explication Raster The output raster.

## Exemple de code

RasterCalculator example 1

Example of a map algebraic expression using a raster calculator.

``````from arcpy.sa import *
out_rc_multi_raster = RasterCalculator(["raster1.tif", "raster2.tif"],
["x", "y"], "x*y")
out_rc_multi_raster.save("C:/arcpyExamples/raster_rc_multi.tif")``````
RasterCalculator example 2

Example of a map algebraic expression using a raster calculator.

``````# Import system modules
import arcpy
from arcpy.sa import *

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

# Set the analysis environments
arcpy.env.workspace = "C:/arcpyExamples/data"

# Set local variables
in_raster1 = "raster1.tif"
in_raster2 = "raster2.tif"

# Excuate RasterCalculator(Minus) function
out_rc_minus_raster = RasterCalculator([in_raster1, in_raster2], ["x", "y"],
"x-y", "", "FirstOf")

# Save the output
out_rc_minus_raster.save("C:/arcpyExamples/raster_rc_minus.tif")``````

#### Rubriques connexes

##### Rubriques connexes
1. An overview of the Spatial Analyst functions