ArcGIS Help 10.1 - Make Route Layer (Network Analyst)

Summary

Makes a route network analysis layer and sets its analysis properties. A route analysis layer is useful for determining the best route between a set of network locations based on a specified network cost.

Usage

After creating the analysis layer with this tool, you can add network analysis objects to it using the Add Locations tool, solve the analysis using the Solve tool, and save the results on disk using Save To Layer File tool.
When using this tool in geoprocessing models, if the model is run as a tool, the output network analysis layer must be made a model parameter; otherwise, the output layer is not added to the table of contents in ArcMap.

Syntax

MakeRouteLayer_na (in_network_dataset, out_network_analysis_layer, impedance_attribute, {find_best_order}, {ordering_type}, {time_windows}, {accumulate_attribute_name}, {UTurn_policy}, {restriction_attribute_name}, {hierarchy}, {hierarchy_settings}, {output_path_shape}, {start_date_time})

Parameter	Explanation	Data Type
in_network_dataset	The network dataset on which the route analysis will be performed.	Network Dataset Layer
out_network_analysis_layer	Name of the route network analysis layer to create.	String
impedance_attribute	The cost attribute to be used as impedance in the analysis.	String
find_best_order (Optional)	FIND_BEST_ORDER —The stops will be reordered to find the optimal route. This option changes the route analysis from a shortest-path problem to a traveling salesperson problem (TSP). USE_INPUT_ORDER —The stops will be visited in the input order. This is the default.	Boolean
ordering_type (Optional)	Specifies the ordering of stops when FIND_BEST_ORDER is used. PRESERVE_BOTH —Preserves the first and last stops by input order as the first and last stops in the route. PRESERVE_FIRST —Preserves the first stop by input order as the first stop in the route, but the last stop is free to be reordered. PRESERVE_LAST —Preserves the last stop by input order as the last stop in the route, but the first stop is free to be reordered. PRESERVE_NONE —Frees both the first and last stop to be reordered.	String
time_windows (Optional)	Specifies whether time windows will be used at the stops. USE_TIMEWINDOWS —The route will consider time windows on the stops. If a stop is arrived at before its time window, there will be wait time until the time window starts. If a stop is arrived at after its time window, there will be a time window violation. Total time window violation is balanced against minimum impedance when computing the route. This is a valid option only when the impedance is in time units. NO_TIMEWINDOWS —The route will ignore time windows on the stops. This is the default.	Boolean
accumulate_attribute_name [accumulate_attribute_name,...] (Optional)	List of cost attributes to be accumulated during analysis. These accumulation attributes are purely for reference; the solver only uses the cost attribute specified by the Impedance attribute parameter to calculate the route. For each cost attribute that is accumulated, a Total_[Impedance] property is added to the routes that are output by the solver.	String
UTurn_policy (Optional)	The U-Turn policy at junctions. Allowing U-turns implies the solver can turn around at a junction and double back on the same street. Given that junctions represent street intersections and dead ends, different vehicles may be able to turn around at some junctions but not at others—it depends on whether the junction represents an intersection or dead end. To accommodate, the U-turn policy parameter is implicitly specified by how many edges connect to the junction, which is known as junction valency. The acceptable values for this parameter are listed below; each is followed by a description of its meaning in terms of junction valency. ALLOW_UTURNS —U-turns are permitted at junctions with any number of connected edges. This is the default value. NO_UTURNS —U-turns are prohibited at all junctions, regardless of junction valency. Note, however, that U-turns are still permitted at network locations even when this setting is chosen; however, you can set the individual network locations' CurbApproach property to prohibit U-turns there as well. ALLOW_DEAD_ENDS_ONLY —U-turns are prohibited at all junctions, except those that have only one adjacent edge (a dead end). ALLOW_DEAD_ENDS_AND_INTERSECTIONS_ONLY —U-turns are prohibited at junctions where exactly two adjacent edges meet but are permitted at intersections (junctions with three or more adjacent edges) and dead ends (junctions with exactly one adjacent edge). Oftentimes, networks have extraneous junctions in the middle of road segments. This option prevents vehicles from making U-turns at these locations. Tip: If you need a more precisely defined U-turn policy, consider adding a global turn delay evaluator to a network cost attribute, or adjusting its settings if one exists, and pay particular attention to the configuration of reverse turns. Also, look at setting the CurbApproach property of your network locations.	String
restriction_attribute_name [restriction_attribute_name,...] (Optional)	List of restriction attributes to apply during the analysis.	String
hierarchy (Optional)	USE_HIERARCHY — Use the hierarchy attribute for the analysis. Using a hierarchy results in the solver preferring higher-order edges to lower-order edges. Hierarchical solves are faster, and they can be used to simulate the preference of a driver who chooses to travel on freeways over local roads when possible—even if that means a longer trip. This option is valid only if the input network dataset has a hierarchy attribute. NO_HIERARCHY —Do not use the hierarchy attribute for the analysis. Not using a hierarchy yields an exact route for the network dataset. The parameter is not used if a hierarchy attribute is not defined on the network dataset used to perform the analysis. In such cases, use "#" as the parameter value.	Boolean
hierarchy_settings (Optional)	Legacy: Prior to version 10, this parameter allowed you to change the hierarchy ranges for your analysis from the default hierarchy ranges established in the network dataset. At version 10, this parameter is no longer supported and should be specified as an empty string. If you wish to change the hierarchy ranges for your analysis, update the default hierarchy ranges in the network dataset.	Network Analyst Hierarchy Settings
output_path_shape (Optional)	Specifies the shape type for the route features that are output by the analysis. TRUE_LINES_WITH_MEASURES —The output routes will have the exact shape of the underlying network sources. Furthermore, the output includes route measurements for linear referencing. The measurements increase from the first stop and record the cumulative impedance to reach a given position. TRUE_LINES_WITHOUT_MEASURES —The output routes will have the exact shape of the underlying network sources. STRAIGHT_LINES —The output route shape will be a single straight line between the stops. NO_LINES —No shape will be generated for the output routes. No matter which output shape type is chosen, the best route is always determined by the network impedance, never Euclidean distance. This means only the route shapes are different, not the underlying traversal of the network.	String
start_date_time (Optional)	Specifies a start date and time for the route. Route start time is mostly used to find routes based on the impedance attribute that varies with the time of the day. For example, a start time of 9 AM could be used to find a route that considers the rush hour traffic. The default value for this parameter is 8:00 AM. A date and time can be specified as 10/21/05 10:30 AM. If the route spans multiple days, and only the start time is specified, then the current date is used. Instead of using a particular date, a day of the week can be specified using the following dates. Today—12/30/1899 Sunday—12/31/1899 Monday—1/1/1900 Tuesday—1/2/1900 Wednesday—1/3/1900 Thursday—1/4/1900 Friday—1/5/1900 Saturday—1/6/1900 For example, to specify that travel should begin at 5:00 PM on Tuesday, specify the parameter value as 1/2/1900 5:00 PM. After the solve, the start and end time of the route are populated in the output routes. These start and end times are also used when directions are generated.	Date

Code Sample

MakeRouteLayer example 1 (Python window)

Execute the tool using only the required parameters.

network = "C:/Data/SanFrancisco.gdb/Transportation/Streets_ND"
arcpy.na.MakeRouteLayer(network, "WorkRoute", "TravelTime")

MakeRouteLayer example 2 (Python window)

Execute the tool using all parameters.

network = "C:/Data/SanFrancisco.gdb/Transportation/Streets_ND"
arcpy.na.MakeRouteLayer(network, "InspectionRoute", "TravelTime",
                        "FIND_BEST_ORDER", "PRESERVE_BOTH", "USE_TIMEWINDOWS",
                        ["Meters", "TravelTime"],
                        "ALLOW_DEAD_ENDS_AND_INTERSECTIONS_ONLY", ["Oneway"],
                        "USE_HIERARCHY", "", "TRUE_LINES_WITH_MEASURES",
                        "1/1/1900 9:00 AM")

MakeRouteLayer example 3 (workflow)

The following stand-alone Python script demonstrates how the MakeRouteLayer tool can be used to find a best route to visit the geocoded stop locations.

# Name: MakeRouteLayer_Workflow.py
# Description: Find a best route to visit the stop locations and save the 
#              route to a layer file. The stop locations are geocoded from a 
#              text file containing the addresses.
# Requirements: Network Analyst Extension 

#Import system modules
import arcpy
from arcpy import env

try:
    #Check out the Network Analyst extension license
    arcpy.CheckOutExtension("Network")

    #Set environment settings
    env.workspace = "C:/data/SanFrancisco.gdb"
    env.overwriteOutput = True
    
    #Set local variables
    inNetworkDataset = "Transportation/Streets_ND"
    outNALayerName = "BestRoute"
    impedanceAttribute = "TravelTime"
    inAddressLocator = "SanFranciscoLocator"
    inAddressTable = "C:/data/StopAddresses.csv"
    inAddressFields = "Street Address VISIBLE NONE"
    outStops = "GeocodedStops"
    outLayerFile = "C:/data/output" + "/" + outNALayerName + ".lyr"
    
    #Create a new Route layer. For this scenario, the default value for all the
    #remaining parameters statisfies the analysis requirements
    outNALayer = arcpy.na.MakeRouteLayer(inNetworkDataset, outNALayerName,
                                         impedanceAttribute)
    
    #Get the layer object from the result object. The route layer can now be
    #referenced using the layer object.
    outNALayer = outNALayer.getOutput(0)
    
    #Get the names of all the sublayers within the route layer.
    subLayerNames = arcpy.na.GetNAClassNames(outNALayer)
    #Stores the layer names that we will use later
    stopsLayerName = subLayerNames["Stops"]
    
    #Geocode the stop locations from a csv file containing the addresses.
    #The Geocode Addresses tool can use a text or csv file as input table
    #as long as the first line in the file contains the field names.
    arcpy.geocoding.GeocodeAddresses(inAddressTable, inAddressLocator, 
                                     inAddressFields, outStops)
    
    #Load the geocoded address locations as stops mapping the address field from
    #geocoded stop features as Name property using field mappings.
    fieldMappings = arcpy.na.NAClassFieldMappings(outNALayer, stopsLayerName)
    fieldMappings["Name"].mappedFieldName = "Address"
    arcpy.na.AddLocations(outNALayer, stopsLayerName, outStops, fieldMappings,
                          "", exclude_restricted_elements = "EXCLUDE")
    
    #Solve the route layer, ignore any invalid locations such as those that
    #can not be geocoded
    arcpy.na.Solve(outNALayer,"SKIP")
    
    #Save the solved route layer as a layer file on disk with relative paths
    arcpy.management.SaveToLayerFile(outNALayer,outLayerFile,"RELATIVE")
    
    print "Script completed successfully"

except Exception as e:
    # If an error occurred, print line number and error message
    import traceback, sys
    tb = sys.exc_info()[2]
    print "An error occured on line %i" % tb.tb_lineno
    print str(e)

Environments

Current Workspace

Licensing Information

ArcGIS for Desktop Basic: Yes

ArcGIS for Desktop Standard: Yes

ArcGIS for Desktop Advanced: Yes

1/20/2015

Make Route Layer (Network Analyst)