ENVSOCTY 3GV3 QUESTIONS & ANSWERS
Why build a Geoprocessing Model? (5) - Answer -- executing single GIS tools is a
practical way to accomplish certain GIS tasks
- often need to run a sequence of tools to solve a problem (GIS is synonymous with
workflows, which can be simple to complex)
- saves time
- easily validated
- tells the computer how to process a sequence of steps
ModelBuilder is designed to... - Answer -- automate workflow processes
- create custom tools for problem solving
- combines ant existing tools from tools into a model
- visual programming language
- models are stored in a project or custom toolbox
8 Steps to Creating and Running a Model - Answer -1. Create a new model
2. Update properties
3. Add data and tools to the model
4. Create connectors and fill in tool parameters
5. Validate the model
6. Save the model
7. Run the model
8. Examine the results
Parameters - Answer -the inputs and outputs of any tool
- either required or optional (required must be set or tool will not run in the model)
When a model is run, output data are created for... - Answer -each process in the
model
- except for "final" output, all derived data are set as intermediate by default
Intermediate Data - Answer -should be deleted after the model is run
You can preserve intermediate data by (3): - Answer -- running the model from the
ModelBuilder window
- removing the intermediate flag by right-clicking on the derived variable and making
sure that Delete Intermediate Data is not checked
- Making intermediate data model parameters
Make sure that your model is easy to read (3): - Answer -- layout is simple, logical, and
aligned
- add labels for additional clarity
- rename elements as necessary to ensure clarity (i.e. not cryptic)
, Caveats to Models (2): - Answer -- simple models are tied 100% to your data
- models need to be parameterized to make them generalizable
Points, lines, and polygons exist within a... - Answer -continuous coordinate space
Point - Answer -one X,Y coordinate pair
Line - Answer -set of connected X,Y coordinate pairs
Area - Answer -closed loop of X,Y coordinate pairs
Spatial Features: High level of precision in terms of ____, _____, and ____ of features.
- Answer -position, length, and area
Georelational Data Model (2) - Answer -- attributes and feature geometries are stored
in different files
- linked between attributes and their geometric are maintained using feature identifiers
(FID)
Feature Identifiers - Answer -FID - links between attributes and their geometric are
maintained using feature identifiers (FID)
Name 2 examples of georelational data models - Answer -- coverage (ArcInfo)
- shapefile (ArcView)
Coverage (5): - Answer -- developed for ArcInfo, 1980
- topologically linked geographic features and their attribute data
- represents a single theme or layer
- primary features are nodes, arcs, and polygons
- secondary features are tics and label points
Two versions of coverages: - Answer -- ArcInfo coverage
- PC ARC/INFO coverage
ArcInfo Coverage - Answer -attributes are store in tables in INFO database
PC ARC/INFO Coverage - Answer -attributes are stored in dBASE tables
Primary features of Coverage (3): - Answer -- nodes
- arcs
- polygons
Secondary features of Coverage (2): - Answer -- tics
- label points
Why build a Geoprocessing Model? (5) - Answer -- executing single GIS tools is a
practical way to accomplish certain GIS tasks
- often need to run a sequence of tools to solve a problem (GIS is synonymous with
workflows, which can be simple to complex)
- saves time
- easily validated
- tells the computer how to process a sequence of steps
ModelBuilder is designed to... - Answer -- automate workflow processes
- create custom tools for problem solving
- combines ant existing tools from tools into a model
- visual programming language
- models are stored in a project or custom toolbox
8 Steps to Creating and Running a Model - Answer -1. Create a new model
2. Update properties
3. Add data and tools to the model
4. Create connectors and fill in tool parameters
5. Validate the model
6. Save the model
7. Run the model
8. Examine the results
Parameters - Answer -the inputs and outputs of any tool
- either required or optional (required must be set or tool will not run in the model)
When a model is run, output data are created for... - Answer -each process in the
model
- except for "final" output, all derived data are set as intermediate by default
Intermediate Data - Answer -should be deleted after the model is run
You can preserve intermediate data by (3): - Answer -- running the model from the
ModelBuilder window
- removing the intermediate flag by right-clicking on the derived variable and making
sure that Delete Intermediate Data is not checked
- Making intermediate data model parameters
Make sure that your model is easy to read (3): - Answer -- layout is simple, logical, and
aligned
- add labels for additional clarity
- rename elements as necessary to ensure clarity (i.e. not cryptic)
, Caveats to Models (2): - Answer -- simple models are tied 100% to your data
- models need to be parameterized to make them generalizable
Points, lines, and polygons exist within a... - Answer -continuous coordinate space
Point - Answer -one X,Y coordinate pair
Line - Answer -set of connected X,Y coordinate pairs
Area - Answer -closed loop of X,Y coordinate pairs
Spatial Features: High level of precision in terms of ____, _____, and ____ of features.
- Answer -position, length, and area
Georelational Data Model (2) - Answer -- attributes and feature geometries are stored
in different files
- linked between attributes and their geometric are maintained using feature identifiers
(FID)
Feature Identifiers - Answer -FID - links between attributes and their geometric are
maintained using feature identifiers (FID)
Name 2 examples of georelational data models - Answer -- coverage (ArcInfo)
- shapefile (ArcView)
Coverage (5): - Answer -- developed for ArcInfo, 1980
- topologically linked geographic features and their attribute data
- represents a single theme or layer
- primary features are nodes, arcs, and polygons
- secondary features are tics and label points
Two versions of coverages: - Answer -- ArcInfo coverage
- PC ARC/INFO coverage
ArcInfo Coverage - Answer -attributes are store in tables in INFO database
PC ARC/INFO Coverage - Answer -attributes are stored in dBASE tables
Primary features of Coverage (3): - Answer -- nodes
- arcs
- polygons
Secondary features of Coverage (2): - Answer -- tics
- label points
