ArcGIS Network Analyst and Network Dataset Jim McKinney ESRI
ArcGIS Network Analyst Everything in ArcView GIS 3x and more Routing Directions Network Analysis Tight Integration with Geoprocessing Models and Scripting ArcToolbox tools New Network Dataset Core Geodatabase enhancement
ArcGIS Network Analyst Network Analyst object model Extensible, support for custom applications Migration path for existing software Workstation Arc/Info Network NetEngine ArcLogistics Route ArcIMS RouteServer Framework for future development New solvers New Network Dataset enhancements
ArcMap ArcGIS Network Analyst (Desktop) Interactive toolbar and dialogs ArcCatalog Dialogs and wizards Geoprocessing Modeling and scripting Toolbox Network Dataset Supports Shapefiles, PGDB, SDE, and SDC Network Analyst Solvers Pathfinding and allocation algorithms Extensible via ArcObjects
Network Extension (Server and Engine) ArcGIS Server Network Extension Centralized computing solution Internet and Intranet support Enterprise computing environment Scaleable and IT compliant ArcGIS Engine Network Extension Embeddable components Lightweight applications
Network Analyst Subsystems ArcToolbox ArcMap ArcCatalog Geoprocessing Network Tools Network Layer and Toolbar Wizard and Property Sheets Network Analyst Network UI Network Dataset Commercial Data PGD SDE Shapefiles SDC Geodatabase Filesystem
Routing Network Analyst Solvers Multi-point routing (time windows supported on stops) Driving Directions Expandable inset maps Auto generation capability Closest Facility Fixed and mobile asset routing Emergency response Service Areas Complex polygon generation Allocation across networks OD Cost Matrix Origin and destination calculations, spatial interaction Custom algorithm support
Network Dataset New network model Enhanced modeling capabilities advanced attribute model support for complex turns and maneuvers support for multi-modal modal networks Supports transportation modeling Designed to work with Network Analyst Extension
Network Dataset Supports Shapefiles Direct use of shapefiles Supports Personal Geodatabase Desktop users Supports Enterprise Geodatabase Large Networks Multi-user user server environments Scalable Supports direct reading of SDC
Goal: Model Real World Networks multi-modal modal network support
Goal: Model Real World Networks Streets A Subway Light Rail multi-modal modal network support B
Typical Pathfinding Parameters Hierarchies Favors higher order (faster) streets Curb approach Approaching a stop from a specific side of the road Default turns Left turns take more time than right turns Penalize movements from lower to higher order road classes Restrictions Based on network attributes Barriers Turn Tables Help to create more accurate paths in network
Route Solver Find a route (set of network elements) through a set of network locations (points) that minimizes an impedance (cost) attribute Find best order Traveling Salesperson Network locations Stops Barriers Network locations properties Stop Sequence Time windows Curb approach Directions available Multiple restriction options possible Barriers Turns
Route with Barriers
Exact Route vs. Hierarchical Route using major Roads Route using all local streets
Closest Facility Solver Given a network location (an incident), find the N closest facilities Examples: Emergency vehicle dispatch Patient to health care provider Customer to stores Input network locations Facilities - usually fixed positions Incidents/events transient positions Barriers Solver Options Number of facilities to find Cutoff distance (e.g. closest ATMs within 3 miles) Hierarchical networks Directions
Directions Generates a series of directions Based on route created by Route or Closest Facility solver Expandable inset maps Unit reporting options Print preview options
Given a network dataset Service Areas Create polygons around specified locations Create service area lines Network Locations Facilities Barriers Solver Options Cutoff (20 min Drive time) Breaks (5, 10, 15 and 20 min drive times) Direction of travel From / To facility Polygon generation Separate or Merge Polygon type Disks or rings
Service Area Polygons 0.5, 1, 1.5, 2, 2.5 minute service areas for the 41 fire stations in San Francisco
Origin Destination Cost Matrix Generate an OD matrix of the cost from each location to all other locations on a network Network Locations Origins Destinations Barriers Solver Options Hierarchical networks Number of destinations Cutoff option For Example: t = time d = distance 1 2 3 4 5 1 2 3 4 5 t,d t,d t,d t,d t,d t,d t,d t,d t,d t,d
Geoprocessing Integration with ArcMap toolbar and Network Analyst Window Works with Network Analysis layers in ArcMap and on disk Models and scripts for batch processing or multi-step analysis
Network Analyst Toolbox Creating Layers Route Closest Facility Service Area: lines and polygons OD Cost Matrix
Models and Scripts
Network Dataset Overview
Network Dataset ArcToolbox ArcMap ArcCatalog Geoprocessing Network Tools Network Layer and Toolbar Wizard Property Sheets UI Network Analyst Network Dataset PGD SDE Shapefiles SDC Geodatabase Filesystem
Network Dataset New network model Enhanced modeling capabilities turns / maneuvers, multi-modal modal networks advanced attribute (weight) model Borrows concepts from topology dirty areas and incremental build Works with Network Analyst extension
Network Dataset Built from simple features no special features like GN Features participation: may also participate in a topology may participate in either a network dataset or geometric network
Line features Network Sources define one or more edge elements Point features define junction elements Turn features define turn elements in network explicitly models subset of possible transitions between edge elements during navigation unspecified transitions assigned default turn attribute value
Turn Features Turns are features Simple line feature class Model a turn as a sequence of any number of connected lines Turns do not alter connectivity, but traversability e.g., U-turn U turn restriction 2 3 4 5 7 6 1
Turn Features Simple two-part turns N-part turns Restrictions based on vehicle characteristics legal restrictions Default turn penalties part of the network attribute model All U-turns U are restricted All left turns cost 30 seconds
Network Elements Three types of elements derived from network sources Edges connect two junctions, bi- directional Junctions connect edges Turns (new)) describe transitions between edges and junctions
Connectivity Model Controls how features are connected Simple rules-based approach User defines connectivity model used when the network is built and the connectivity is updated Connectivity is consumed by tools implementing analysis algorithms
Connectivity Model Supports definition of multi-modal modal networks ocean freighter, rail, and road network road, highway, subway, and bus network water, sewer, and stormwater network Two typical usage patterns endpoint elevation simplest (ArcView 3.X) midspan / multi-modal modal extending the GN model with connectivity groups
Point Feature Connectivity Point classes may span multiple connectivity groups used to create connectivity between lines in different groups Connectivity Group 2 Connectivity Group 1
Attributes Control navigation through the network May be used to accumulate information Associated with network elements similar to weights in a geometric network All elements have the same set of attributes Edge elements are directed attributes defined for the edge in either direction
Attribute Types Cost accumulated as you traverse a network element (e.g., distance, travel time) Descriptor true for the entire length of the element (e.g., material type) Restriction like a boolean condition (e.g., no travel on one-way roads) Hierarchy three level classification of edge elements; e.g., 1 = highway 2 = major road 3 = surface street
Evaluators Return the value of an attribute for a network element Three provided: Constant Field VBScript Custom evaluators can be written by third parties
Network Dataset Summary Motivated by transportation industry Contain edges, junctions, and turns Connectivity re-established established at user- controlled times Multi-modal connectivity models Richer attribute model Features may participate in a topology Shapefile support Requires network analyst extension
Thank You Questions?