Transcript ppt

Writing Geoprocessing Scripts
With ArcGIS
Lecture 9
GIS System
ArcObjects
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ArcObjects are the building blocks of ArcGIS. With
ArcObjects, you can create your own menus, tools,
workflows, applications, and custom feature classes
for use with ArcGIS.
ESRI ArcObjects is the development platform for the
ArcGIS family of applications, such as ArcMap,
ArcCatalog, ArcScene, ArcGIS Engine, and ArcGIS
Server. The ArcObjects software components expose
the full range of functionality available in ArcInfo,
ArcEditor, and ArcView to software developers
Can use VBA, Python, C++, Java to program
COM (Component Object
Model) is an interface
standard for software
componentry introduced by
Microsoft in 1993. It is
used to enable interprocess
communication and
dynamic object creation in
a large range of
Python 2.5: import sys, string, os, arcgisscripting programming languages
Python 2.5: gp = arcgisscripting.create()
Python Basics
Variable index
Word =
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Word[0]=‘H’
Word[2:4]=‘lp’
Word[:3]=‘Hel’
Word[-2:-4]=‘el’
Word[-3:]=‘lpA’
Scripts Examples
Does not work in
your new version 2.5
Create a new geoprocessor
Add the toolbox
How to run a python script
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You can run a script as a standalone operation or you
can add a script to a toolbox and then run the script
from its dialog box or incorporate it into a model.
Running a script as a standalone operation means
that you can accomplish geoprocessing without ever
opening an ArcGIS Desktop application. For
example, you can run scripts from within a script
editor, like Pythonwin, or from the command
prompt.
Example: Extract the radar rainfall
using
raingauges location.
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Objective: compare the radar and rain gauge
rainfall measurements
Data source:
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Polygon-feature class of radar rainfall (>10k files);
Point-feature of rain gauge locations (50 gauges);
Method: interception
Final format: all values are stored at one *.txt file.
Study Area