Migrating from ArcView GIS Network Analyst
These workflows discuss the steps to migrate from ArcView GIS Network Analyst to the ArcGIS Network Analyst extension
ArcGIS uses network datasets for network analyses. Network datasets can exist in shapefile workspaces or geodatabase workspaces. Additionally, the ArcGIS Network Analyst extension can perform analysis by directly reading SDC data.
If you have your source data, such as streets in shapefiles, you can choose the type of network dataset you want to create. You can create a shapefile-based network dataset or a geodatabase-based network dataset.
Shapefile-based networks
If you have a single edge source in shapefile format that you want to use for network analysis, you may prefer to create a shapefile network dataset. The ArcGIS Network Analyst extension can automatically recognize and set up cost, restriction, and hierarchy attributes by inspecting your shapefile and searching for commonly used fields, such as Meters, Minutes, Oneway, and Hierarchy. For shapefile-based networks, the source is maintained in the original shapefile format.
Geodatabase-based networks
If you want to model multimodal networks or have multiple sources that connect to each other using sophisticated connectivity rules, you may prefer to create your network dataset in a geodatabase workspace. In this case, sources are maintained as feature classes in a geodatabase. They can participate in a topology. The connectivity model of a geodatabase-based network dataset supports subtypes and multiple edge and junction sources.
Migrating from ArcView GIS to a shapefile-based network dataset
Migrating from ArcView GIS to a shapefile-based network dataset involves the following steps:
- Inspect the geometry of the shapefile.
To perform network analysis on a shapefile network dataset, the source shapefile should have vertices at every intersecting edge. This is essential for establishing connectivity. If the shapefile has lines intersecting each other with no vertex at the intersection, there is no connectivity at that intersection. You should modify the source data before beginning migration to insert vertices at intersections. You can use the Integrate geoprocessing tool to create shared vertices.
- Inspect the attribute table of the shapefile.
You need a cost attribute in your network dataset for performing network analysis. If you have at least one numeric field in the shapefile representing length or time, you can use that field to create a cost attribute. This cost attribute can be used as an impedance for network analysis. If you have no such field in the shapefile, do one of the following:
- Create a field in the shapefile, add length or time values to it, then use it to create a cost attribute for the network dataset.
- Create a cost attribute in the network dataset and assign values to it using a constant evaluator, a field expression that uses other fields of the shapefile, or a VBScript.
- Optionally, you can import turn tables (if any) into turn shapefiles that can be used in the network dataset Learn about migrating turn data.
- Prepare the design for the network dataset.
It is essential to understand the various components of a network dataset and prepare a design of the network. This includes modeling connectivity and thinking about network attributes and their evaluators.
- Create the shapefile-based network dataset.
This step involves the creation of the schema for the network dataset.
- Build the network dataset.
Building a network dataset involves the creation of network elements from shapefile sources, establishment of connectivity, calculation of network attributes, and the setting of properties for directions.
Migrating from ArcView GIS to a geodatabase-based network dataset
Migrating from ArcView GIS to a geodatabase-based network involves the following steps:
- Create a personal geodatabase.Optionally, you can create an enterprise geodatabase or choose an existing geodatabase.
- Create a feature dataset with the same spatial reference as the shapefile.Optionally, you can import the shapefile into an existing feature dataset.
- Importing the shapefile into a feature class within the feature dataset If you have multiple shapefiles you want to use as sources, you should import all of them into feature classes within the same feature dataset.
- Inspect the geometry of the feature class.
To perform network analysis, the network source should have vertices at every intersecting edge. This is essential for establishing connectivity. If you have lines intersecting each other with no vertex at the intersection, there is no connectivity at that intersection. You can modify the source data before beginning migration. Alternately, you can modify the feature class in ArcMap to ensure that coincident vertices are present where required. One option is to have the feature class participate in a topology to insert vertices at places of intersection. Another is to use the Integrate geoprocessing tool.
- Inspect the attribute table of the feature class.
You need a cost attribute in your network dataset for performing network analysis. If you have at least one numeric field in the feature class representing length or time, you can use that field to create a cost attribute. This cost attribute can be used as an impedance for network analysis. If you have no such field in the feature class, you can do one of the following:
- Create a field in the feature class, add length or time values to it, then use it to create a cost attribute for the network dataset.
- Create a cost attribute in the network dataset and assign values to it using a constant evaluator, a field expression that uses other fields of the feature class, or a VBScript.
- Optionally, you can import turn tables (if any) into turn feature classes that can be used in the network dataset.
- Prepare the design for the network dataset.
It is essential to understand the various components of a network dataset and prepare a design of the network. This includes modeling connectivity and thinking about network attributes and their evaluators.
- Create the geodatabase-based network dataset.
This involves the creation of the schema for the network dataset.
- Build the network dataset.
Building a network dataset involves the creation of network elements from the sources, establishment of connectivity, calculation of network attributes, and the setting of properties for directions.