Summary
Generates turn-by-turn directions from a network analysis layer with routes. The directions can be written to a file in text, XML, or HTML format. If you provide an appropriate stylesheet, the directions can be written to any other file format.
Usage
The tool solves the network analysis layer if it does not already have a valid result, so it is not required to solve the network analysis layer before generating directions.
Syntax
Directions(in_network_analysis_layer, file_type, out_directions_file, report_units, {report_time}, {time_attribute}, {language}, {style_name}, {stylesheet})
Parameter | Explanation | Data Type |
in_network_analysis_layer | Network analysis layer for which directions will be generated. Directions can be generated only for route, closest facility, and vehicle routing problem network analysis layers. | Network Analyst Layer |
file_type | The format of the output directions file. This parameter is ignored if the stylesheet parameter has a value.
| String |
out_directions_file | If you provide a stylesheet in the stylesheet parameter, make sure the file suffix for out_directions_file matches the file type your stylesheet produces. | File |
report_units | Specifies the linear units in which the length information will be reported in the directions file. For example, even though your impedance was in meters, you can show directions in miles.
| String |
report_time (Optional) |
| Boolean |
time_attribute (Optional) | The time-based cost attribute to provide travel times in the directions. The cost attribute must exist on the network dataset used by the input network analysis layer. | String |
language (Optional) |
Choose a language in which to generate driving directions. The languages that are shown in the drop-down list depend on which ArcGIS language packs are installed on your computer. Note that if you are going to publish this tool as part of a service on a separate server, the ArcGIS language pack that corresponds with the language you choose must be installed on that server for the tool to function properly. Also, if a language pack isn't installed on your computer, the language won't appear in the drop-down list; however, you can type a language code instead of choosing one. | String |
style_name (Optional) | Choose the name of the formatting style for the directions.
| String |
stylesheet (Optional) | The stylesheet for generating a formatted output file type (such as a PDF, Word, or HTML file). The suffix of the file in the output directions file parameter should match the file type that the stylesheet generates. The Directions tool overrides the output file type parameter if this parameter contains a value.
| File |
Derived Output
Name | Explanation | Data Type |
output_layer | The updated network analysis layer with routes. | Network Analyst Layer |
Code sample
Directions example 1 (Python window)
Execute the Directions tool with all the parameters.
arcpy.na.Directions("Route", "TEXT", "C:/Data/Route_Directions.txt", "Miles",
"REPORT_TIME", "Minutes")
Directions example 2 (workflow)
The following stand-alone Python script demonstrates how the Directions tool can be used to generate driving directions in a HTML file for a route.
# Name: Directions_Workflow.py
# Description: Generate driving directions in a html file for a route that
# visits the store locations in the best sequence that minimizes
# the total travel time
# 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 = "StoreRoute"
impedanceAttribute = "TravelTime"
startLocation = "Analysis/DistributionCenter"
storeLocations = "Analysis/Stores"
#fieldMappings = "Name Name #; Attr_TravelTime ServiceTime #"
outDirectionsFile = "C:/data/output" + "/" + outNALayerName + "Directions.html"
outLayerFile = "C:/data/output" + "/" + outNALayerName + ".lyr"
#Create a new route layer. The route starts at the distribution center and
#takes the best sequence to visit the store locations.
outNALayer = arcpy.na.MakeRouteLayer(inNetworkDataset, outNALayerName,
impedanceAttribute, "FIND_BEST_ORDER",
"PRESERVE_FIRST","",['Meters'],
"NO_UTURNS",start_date_time="8 AM")
#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"]
#Load the distribution center as the start location using default field
#mappings and search tolerance
arcpy.na.AddLocations(outNALayer,stopsLayerName,startLocation,"","",
exclude_restricted_elements = "EXCLUDE")
#Load the store locations as stops. Make sure the store locations are
#appended to the Stops sublayer which already contains the distribution
#center location. Map the Attr_TravelTime property from the ServiceTime
#field so that the total travel time for the route will also contain the
#service time using the field mappings
fieldMappings = arcpy.na.NAClassFieldMappings(outNALayer, stopsLayerName)
fieldMappings["Name"].mappedFieldName = "Name"
fieldMappings["Attr_" + impedanceAttribute].mappedFieldName = "ServiceTime"
arcpy.na.AddLocations(outNALayer, stopsLayerName, storeLocations,
fieldMappings, "", append="APPEND",
exclude_restricted_elements = "EXCLUDE")
#Generate driving directions in a HTML file
arcpy.na.Directions(outNALayer,"HTML",outDirectionsFile,"Miles",
"REPORT_TIME",impedanceAttribute)
#Save the solved na layer as a layer file on disk using relative paths
arcpy.SaveToLayerFile_management(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 occurred on line %i" % tb.tb_lineno
print str(e)
Environments
Licensing information
- Basic: Requires Network Analyst
- Standard: Requires Network Analyst
- Advanced: Requires Network Analyst