networkServiceArea

Service Area

Calculates the service area for the input points based on the cost along the Bidirectional Network (BDN) used. The result is a polygon feature layer with a polygon for each input point. A CutOff distance/cost can be used (a single value for all points or different for each point based on the values in the attribute table of the input point layer).

Inputs:

A Network created with ET GeoWizards (.etn file). Must be a Bidirectional Network (BDN)
Input Point layer representing the centers to be used for partitioning.
Snap tolerance - a distance to the network features. If the points are closer than this distance to a network feature they will be used in the analysis otherwise they will be ignored. The distance is in the linear units of the spatial reference used as a source for creation of the Network.

Input Point Barrier layer. The points of this layer represent barriers. The closest edge to each of these points (if within the snap tolerance) will be considered closed and will not participate in the network analysis.
Direction field for the Input Point Barrier layer. In Bidirectional network the barriers can be set for only one of the directions. This can be indicated if the Barrier Point dataset has a field that indicates in which direction the barrier works.

FT - indicates the Barrier will prohibit movement only in the direction of the polyline. Movement against the direction of the polyline is allowed.
TF - indicates the Barrier will prohibit movement only against the direction of the polyline. Movement in the direction of the polyline is allowed.
Any other values in the Direction field will prohibit movement in both directions

CutOff Cost - links for which the cost is larger than this value will not be included in the output.If the CutOff cost is 0 then no limitations are used.
CutOff Field which value define the CutOff Cost for each center point.
The user can specify to the output to be added a polygon representing areas that cannot be reached from the input points.

Outputs:

A Polygon feature layer representing the service areas of all input points based on the proximity (least cost0 to the input center points.
The attribute table of the output will have 4 fields.

ET_Zone - indicates the ID of the Center point for this zone
TOT_Dist - the total length of the links included in this zone in the linear units of the spatial reference used as a source for creation of the Network.
TOT_Cost - the sum of the costs of all links included in this zone in the units of the cost used by the Network (meters, feet, minutes, etc.)
MAX_Cost - the maximum accumulated cost to reach the farthest location in this zone from the center in the units of the cost used by the Network (meters, feet, minutes, etc.)

Notes :

It is recommended that the input point layer has the same spatial reference as the layer used as a source for the Network.
If the spatial reference of the points and the Network are different, the points will be projected to the spatial reference of the Network.
The result layer will have the spatial reference of the Network.

Example:

Results - Assigned service areas - No CutOff Cost used.

Assigned service areas - No CutOff Cost used

Results - Assigned service areas - CutOff Cost = 15 kilometers used.

Assigned service areas - CutOff Cost = 15 kilometers used

Running Programmatically

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Parameters

Expression	Explanation
Function Name	ServiceArea
<Network to Use>	A String - the full name of the Network file (.etn).
<Input Points>	A String representing the input layer. Must be of Point type.
<output dataset>	A String - the full name of the output layer.
<snap tolerance>	A Double representing the snap tolerance(in the units of the spatial reference of the Network).
{Input Barrier Points}	A String representing the input layer with barrier points. Must be of Point type.
{Barriers Direction Field}	A String representing the name of the field in the Input Barrier Points that will indicate the direction in which the barrier defined by each point work . Must be of String type.
{CutOff Cost}	A Double representing the CutOff Costs in the units of the Network costs.
{CutOff Field}	A String representing the Name of the field to be used to sort the points of the Input Point layer to establish the sequence in which they will be visited.
{Include No Reach Areas}	A Boolean.

Running the function

ETGWPath used in the table below is the full path to ETGWRun.exe (E.G. "C:\Program Files\ETSpatial Techniques\ETGeo Wizards\ETGWRun.exe")

Language	Syntax
Python	subprocess.call([ETGWPath, "ServiceArea", "Network to Use", "Input Points", "output dataset","snap tolerance", "Input Barrier Points", "Barriers Direction Field","CutOff Cost", "CutOff Field" "Include No Reach Areas"])
.NET using ETGWRun.exe	StartInfo.FileName = ETGWPath StartInfo.Arguments = "ServiceArea" "Network to Use" "Input Points" "output dataset" "snap tolerance" "Input Barrier Points" "Barriers Direction Field" "CutOff Cost" "CutOff Field" "Include No Reach Areas"
.NET using ETGWOutX.dll	ServiceArea(Network to Use,Input Points, output dataset, snap tolerance,Input Barrier Points, Barriers Direction Field CutOff Cost, CutOff Field,Include No Reach Areas)
ArcPy	arcpy.ServiceArea(Network to Use,Input Points, output dataset, snap tolerance, Input Barrier Points, Barriers Direction Field, CutOff Cost, CutOff Field, Include No Reach Areas)

Notes:

<> - required parameter
{} - optional parameter
See examples for Python , .NET or ArcPy
The argument separator for StartInfo.Arguments is space. If a string might contain a space, you need to double quote it.

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