Exp (Image Analyst)

Available with Spatial Analyst license.

Summary

Calculates the base e exponential of the cells in a raster.

Illustration

OutRas = Exp(InRas1)

Usage

• Input values can be integer or float as well as negative or positive.

  You can review some results for both positive and negative floating-point input values in the examples of output values from the Exponential tools.

• 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 raster from this tool is always floating-point type, regardless of the input value type.

• Output values from this tool are always positive.

• If the input is a multiband raster, the output will be a multiband raster. The tool will perform the operation on each band in the input.

• If the input is multidimensional raster data, all slices from all variables will be processed. The output will be a multidimensional raster in CRF format.

Parameters

Dialog

Label	Explanation	Data Type
Input raster or constant value	The input values for which to find the base e exponential. 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

Label	Explanation	Data Type
Output raster	The output raster. The cell values are the base e exponential of the input values.	Raster

Python

Exp(in_raster_or_constant)

Name	Explanation	Data Type
in_raster_or_constant	The input values for which to find the base e exponential. 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 base e exponential of the input values.	Raster

Code sample

Exp example 1 (Python window)

This example calculates the base e exponential of the input raster values, and returns the result as a TIFF raster.

import arcpy
from arcpy import env
from arcpy.ia import *
env.workspace = "C:/iapyexamples/data"
outExp = Exp("landuse")
outExp.save("C:/iapyexamples/output/outexp.tif")

Exp example 2 (stand-alone script)

This example calculates the base e exponential of the input raster values.

# Name: Exp_Ex_02.py
# Description: Calculates the base e exponential of pixels in a raster
# Requirements: Image Analyst Extension

# Import system modules
import arcpy
from arcpy import env
from arcpy.ia import *

# Set environment settings
env.workspace = "C:/iapyexamples/data"

# Set local variables
inRaster = "landuse"

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

# Execute Exp
outExp = Exp(inRaster)

# Save the output 
outExp.save("C:/iapyexamples/output/outexp")

Environments

Auto Commit, Cell Size, Cell Size Projection Method, Current Workspace, Extent, Geographic Transformations, Mask, Output CONFIG Keyword, Output Coordinate System, Scratch Workspace, Snap Raster, Tile Size