Exp

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Map Algebra:
OutRas = Exp(InRas1)
Command Line:
outRas = Exp("InRas1")

Usage tips

Command line and Scripting

• Output values are always floating point, regardless of the input values.

• The base e exponential is the most commonly used exponential function.

• Input values less than or equal to -745 will be set to NoData in the output, because these values cannot be accurately represented by 32-bit floating-point numbers.

• A number can be used as an input; however, the cell size and extent must first be set in the environment.

• The following environment settings affect this tool:

  • General: Current Workspace, Scratch Workspace, Output Coordinate system, Output Extent, Snap Raster.
  • Raster Analysis: Cell size, Mask.
  • Raster Storage: See the Raster Storage settings for the particular output raster format selected.

Map Algebra

• Output values are always floating point, regardless of the input values.

• The base e exponential is the most commonly used exponential function.

• Input values less than or equal to -745 will be set to NoData in the output, because these values cannot be accurately represented by 32-bit floating-point numbers.

• Learn more about how to specify the input raster dataset in the Map Algebra expression of Raster Calculator.

ArcObjects

• Output values are always floating point, regardless of the input values.

• The base e exponential is the most commonly used exponential function.

• Input values less than or equal to -745 will be set to NoData in the output, because these values cannot be accurately represented by 32-bit floating-point numbers.

• The output from the ArcObjects method is a raster object.

• A number cannot be used as input to the ArcObjects method. If a constant number must be passed to the method, create a constant raster using IRasterMakerOp::MakeConstant, then pass the results to the method.

Command line syntax
An overview of the Command Line window
Exp_sa <in_raster_or_constant> <out_raster>

Command line example

Exp_sa C:/data/ras_1 C:/data/final_1

Scripting syntax
About getting started with writing geoprocessing scripts
Exp_sa (in_raster_or_constant, out_raster)

Script example

# Exp_sample.py
# Description: 
#   Calculates the base e exponential of the input on a 
#   cell-by-cell basis.
# Requirements: None
# Author: ESRI
# Date: Sept 6, 2005
# Import system modules
import arcgisscripting

# Create the Geoprocessor object
gp = arcgisscripting.create()

try:
    # Set the input raster dataset
    inputRaster = "C:/data/ras_1"

    # Set the output raster name
    outputRaster = "C:/data/final_1"

    # Check out Spatial Analyst extension license
    gp.CheckOutExtension("Spatial")

    # Process: Exp
    gp.Exp_sa(inputRaster, outputRaster)

except:
    # If an error occurred while running a tool, then print the messages.
    print gp.GetMessages()

Map Algebra syntax
Exp(<grid | number>)

Map Algebra example

exp(ingrid)
exp(ingrid1 + ingrid2)
exp(ingrid1 div pi)

ArcObjects syntax
IMathOp::Exp (geoDataset As IGeoDataset) As IGeoDataset

ArcObjects example

' Create the RasterMathOps object
Dim pMathOp As IMathOp
Set pMathOp = New RasterMathOps

' Declare the input raster object
Dim pInputDataset As IGeoDataset

' Calls function to open a raster dataset from disk
Set pInputDataset = OpenRasterDataset ("D:\SpatialData", "inputraster")

' Declare the output raster object
Dim pOutputRaster As IGeoDataset

' Calls the method
Set pOutputRaster = pMathOp.Exp (pInputDataset)