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Walk Distance Maps & AnalysisUsing Network Analyst
by Christy Jacobsby Christy Jacobs
What’s a walk distance map?
WalkDistance Polygons
School
A A walk distance mapwalk distance map is a map of one or more individual is a map of one or more individual polygons around each school of interest. Each polygon is polygons around each school of interest. Each polygon is
created around a school and designates an area of a created around a school and designates an area of a certain distance on the street network. A lot of times these certain distance on the street network. A lot of times these polygons are used to analyze and count students that are polygons are used to analyze and count students that are
within the designated walking distance of each school.within the designated walking distance of each school.
Introducing Network Analyst
• Network Analyst allows you to create and manage network data sets and generate routing systems
• Use for network-based spatial analysis
- location analysis
- spatial interaction modeling
Using Network Analyst – Analyses Types
• Finding the best route- the shortest or most scenic route from set location to set location
• Finding the closest facility
• Finding a service area - finding the service areas around facilities
based on a cost attribute (length/distance, time)
• Creating an OD (Origin-Destination) Cost Matrix - used for routing of multiple originations to one destination and manages
individual impedances for each origination
• What’s a Service Area in Network Analyst?- the area around a facility, based on a
network, that the facility can service depending on
the cost attribute
Understanding Service Areas
In this map in Network Analyst terms :
The cost attribute is miles, schools are the facilities and the service area is the 1- mile area shown as a polygon on the street network in the area around the school
Service Area Polygon
Facility Point
In this map:Each blue area
displays the area within 1 mile
of each school, based on the
street network around the
school
Creating Network Analyst Datasets
Before beginning to work with Network Analyst to create network routing and areas, you have to create a network
dataset to work with:
Creating Network Analyst Datasets
In ArcCatalog, right click on the dataset that contains the data to be used in the Network dataset
New NetworkAnalyst Wizard
Go to “New”, then click on “Network Dataset”
Creating Network Analyst Datasets
Name theNetworkDataset
Choose the
participating data
Connectivitysettings
Creating Network Analyst Datasets
Modeling
Turns
Elevation Data Settings
Creating Network Analyst Datasets
Choose Cost AttributesCan UseShape Length
as aCost
Attribute
Creating Network Analyst Datasets
Set DrivingDirections, if desired
Summary
Click on “Finish” and then when prompted to
“Build” the network dataset,
select “Yes”
Introducing the Network Analyst Extension toolbar
Check onNetworkAnalystToolbar
Note: Be sure the extension is turned on in Tools – Extensions before bringing in
the Network Analyst toolbar
Navigating the Network Analyst toolbar
Choose Network type
Create NetworkLocation Tool
Select/Move NetworkLocation Tool
Active NetworkDataset
NetworkIdentify
Tool
SolveButton
BuildButton
Show/HideNetworkAnalystWindow
Network Analyst in ArcMap
NetworkAnalystWindow
NetworkAnalystLayers
• What’s a Service Area in Network Analyst?- the area around a facility, based on a
network, that the facility can service depending on
the cost attribute
Review of Service Area Features
In this map in Network Analyst terms :
The cost attribute is miles, schools are the facilities and the service area is the 1- mile area shown as a polygon on the street network in the area around the school
Service Area Polygon
Facility Point
In this map:Each blue area
displays the area within 1 mile
of each school, based on the
street network around the
school
I have walk distance polygons of 1 mile.I have walk distance polygons of 1 mile.
Now what??Now what??
Using Service Areas to Analyze Walk Distance and Student Location
Bring in yourBring in your
students file students file and select, and select, query and query and
analyze the analyze the students that students that are within the are within the walk distances walk distances
polygons or polygons or outsideoutside
Use “Select by Location” to
isolate students that reside within the polygons
Using Network Analyst
Let’s use Network Analyst to create a service area that displays a walk/drive distance of 1 mile
around school locations, then select students that are within those service area polygons