Class 12: Using Model Builder to Automate GIS Processes

1
Class 12 Using Model Builder to Automate GIS
Processes

• GEOG CP350 GIS Modeling and Analysis
• GIS Certificate Program
• University of Washington Extension
• Winter 2008

2
This evening

• Model Builder Lecture
• Model Builder Demo
• Model Builder Exercise
• No class next week!

3
On a lighter note

• Historic Maps WSU Map Library
• http//www.wsulibs.wsu.edu/holland/masc/xmaps.html
  

4
(No Transcript)
5
ESRI Model Builder

• modeling A set of rules and procedures for
  representing a phenomenon or predicting an
  outcome.
• data models A data representation of reality,
  such as the vector data model.
• ESRI software In geoprocessing in ArcGIS, one
  process or a sequence of processes connected
  together, that is created in ModelBuilder.

6
What is a model?

• A representation of reality
• Example a recipe

Triple Sec
Ice
Lime
Mix
Tequila
Margarita
Glass
Salt Rim
Salt
7
What can I do with ModelBuilder?

• Design a model
• Implement a model
• Automate work flow by stringing processes
  together (can be saved to run again)
• First steps in programming or scripting
• Create a model containing methods procedures to
  be shared with others
• Show the process used to create output (flow
  diagrams)

8
Model Builder Components
9
The ModelBuilder Interface ModelBuilder window
where you edit, test and run models
Navigate
Zoom In
Auto Layout
ModelBuilder Canvas
Zoom out
Continuous Zoom
Full Extent
Run
Select
Add Connection
10
The ModelBuilder Interface, cont.

• Model elements have 3 states
• Not ready to run (parameters arent defined)
• Ready to run (all elements are colored)
• Already run (elements are colored and shaded)

Usually referred to as Derived Data
output
Input
tool
11
Start building your model!

• First, plan what you want to do
• What data will you need?
• What processes will you run on each dataset?
• If the ModelBuilder Window is closed, right-click
  the model and choose Edit to open for editing
• Add data layers to the canvas using the or
  drag them in from ArcCatalog
• Drag tools onto the canvas from ArcToolbox
• Connect data layers to tools using the tool

12
Running a model in a dialog

• Once the model is created, tested saved in the
  ModelBuilder Window, it can be run as a dialog
  from ArcToolBox (like a tool)
• In ArcToolBox, navigate to your tool
• Double click the tool enter the necessary
  parameters
• Optionally, change the name location of input
  or output data
• Click OK
• Check specified output folder for results

13
Model Strengths and Weaknesses

• Drawbacks
• Models can become unwieldy
• QA/QC issues
• Requires good documentation
• Can create LARGE amounts of data

• Advantages
• Increases Analysis efficiency
• Automates often used processes
• Allows for sharing of models
• Parcel analysis, stream buffers

14
Pollutant Load Model (2)Input LULC Raster
formatArcGIS 9 Model Builder
15
Pollutant Load Model

• Simplified, GIS-based application
• Developed in ArcGIS 9.x (Model Builder)
• Raster data model
• Estimates total pollutant loads (NPS) in lbs /
  yr, for any user-specified pollutant
• Based on the empirical Simple Method developed by
  Schueler (1987) for estimating pollutant export
  from small urban watersheds

16
This Evenings Activities.

• Please create an XXX PortfolioW08 folder within
  your directory to save results from this
  quarters exercises
• Tonights exercise Spatial Analysis with Vector
  Data
• Start on Virtual Campus Spatial Analyst course