Importing the Spatial Analyst module

Spatial Analyst (arcpy.sa) is a module of the ArcPy site package. The simplest way to access Spatial Analyst functionality, including tools, operators, functions, and classes, is to import from the sa module. Using this import method makes it possible to access Spatial Analyst functionality without providing a name space and imports overloaded operators, which allows rasters to be used with operators.

The recommended sequence of imports to utilize Spatial Analyst functionality is shown below.

import arcpy
from arcpy import env
from arcpy.sa import *

This approach allows you to:

• Set and get environment settings prefixed simply with env.

  env.workspace = "c:/base/data.gdb"

• Run geoprocessing tools and functionality directly from arcpy.

  arcpy.Buffer_analysis("infeatures", "outbuffer", 5000)

• Use Map Algebra without having to prefix every tool and class with arcpy.sa.

  outRas = Sin("inraster1") + Raster("inraster2") + 8
  

To learn more about your options when importing ArcPy, Map Algebra or other functionality, see Importing ArcPy.

许可:

In Python (or when in the Python window and the Spatial Analyst extension has not already been enabled), you will need to check out a Spatial Analyst license before running a tool.

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

Customizing your interactive Python experience

The Python window (or any other interactive Python interpreter) recognizes the system environment variable PYTHONSTARTUP. If PYTHONSTARTUP has been previously set to a Python file, Python will automatically execute that file's code when the Python window is opened. This is a useful way to ensure that your Python window experience starts with all your commonly used Python utilities preloaded.

# File: pythonstartup.py
# Description: Used to customize the state of the python start up environment 
#   upon startup of ArcGIS application
#   Can specify module imports, variables, messages
# Requirements: Spatial Analyst Extension
# Author: ESRI

# Print to screen
print "%s\n%s\n%s" %("import os, sys, string","import arcpy", "from arcpy.sa import *")

# Imports
import os, sys, string
import arcpy
from arcpy import env
from arcpy.sa import *

要添加 PYTHONSTARTUP 环境设置，请执行以下操作：

1. 右键单击我的电脑，然后单击属性。
2. 单击高级选项卡，然后单击环境变量。
3. 在系统变量下，单击新建。
4. 将 PYTHONSTARTUP 添加到变量名中。
5. 将 Python 文件的路径添加到变量值，然后单击确定。
6. 单击确定。