Summary
Makes a closest facility network analysis layer and sets its analysis properties. A closest facility analysis layer is useful in determining the closest facility or facilities to an incident based on a specified travel mode. The layer can be created using a local network dataset or using a service hosted online or in a portal.
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 the 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 contents of the map.
In ArcGIS Pro, network analysis layer data is stored on disk in file geodatabase feature classes. When creating a network analysis layer in a project, the layer's data will be created in a new feature dataset in the Current Workspace environment. When creating a network analysis layer in a Python script, you must first explicitly set the workspace environment to a file geodatabase where you want the layer's data to be stored using arcpy.env.workspace = "<path to file gdb>". When the layer is created, a new feature dataset containing the appropriate sublayer feature classes will be added to this file geodatabase.
Syntax
MakeClosestFacilityAnalysisLayer(network_data_source, {layer_name}, {travel_mode}, {travel_direction}, {cutoff}, {number_of_facilities_to_find}, {time_of_day}, {time_zone}, {time_of_day_usage}, {line_shape}, {accumulate_attributes}, {generate_directions_on_solve})| Parameter | Explanation | Data Type |
network_data_source | The network dataset or service on which the network analysis will be performed. Use the portal URL for a service. | Network Dataset Layer;String |
layer_name (Optional) | The name of the network analysis layer to create. | String |
travel_mode (Optional) | The name of the travel mode to use in the analysis. The travel mode represents a collection of network settings, such as travel restrictions and U-turn policies, that determine how a pedestrian, car, truck, or other medium of transportation moves through the network. Travel modes are defined on your network data source. An arcpy.na.TravelMode object and a string containing the valid JSON representation of a travel mode can also be used as input to the parameter. | String |
travel_direction (Optional) | Specifies the direction of travel between facilities and incidents.
The direction of travel may influence the facilities found if the network contains one-way streets or impedances based on the direction of travel. For instance, it might take 10 minutes to drive from a particular incident to a particular facility, but the journey might take 15 minutes traveling in the other direction, from the facility to the incident, because of one-way streets or different traffic conditions. | String |
cutoff (Optional) | The impedance value at which to stop searching for facilities for a given incident in the units of the impedance attribute used by your chosen travel_mode. This cutoff can be overridden on a per-incident basis by specifying individual cutoff values in the incidents sublayer when travel_direction='TO_FACILITIES' or on a per-facility basis by specifying individual cutoff values in the facilities sublayer when travel_direction='FROM_FACILITIES'By default, no cutoff is used for the analysis. | Double |
number_of_facilities_to_find (Optional) | The number of closest facilities to find per incident. This default can be overridden by specifying an individual value for the TargetFacilityCount property in the incidents sublayer. The default number of facilities to find is one. | Long |
time_of_day (Optional) | Specifies the time and date at which the routes should begin or end. The interpretation of this value depends on whether time_of_day_usage is set to be the start time or the end time of the route. If you have chosen a traffic-based impedance attribute, the solution will be generated given dynamic traffic conditions at the time of day specified here. A date and time can be specified as 5/14/2012 10:30 AM. Instead of using a particular date, a day of the week can be specified using the following dates:
| Date |
time_zone (Optional) | Specifies the time zone for the time_of_day parameter.
| String |
time_of_day_usage (Optional) | Indicates whether the value of the time_of_day parameter represents the arrival or departure time for the route or routes.
| String |
line_shape (Optional) | Specifies the shape type for the route features that are output by the analysis. No matter which output shape type is chosen, the best route is always determined by the network impedance, never Euclidean distance. This means that only the route shapes are different, not the underlying traversal of the network.
| String |
accumulate_attributes [accumulate_attributes,...] (Optional) | A list of cost attributes to be accumulated during analysis. These accumulated attributes are for reference only; the solver only uses the cost attribute used by your designated travel mode when solving the analysis. For each cost attribute that is accumulated, a Total_[Impedance] property is populated in the network analysis output features. This parameter is not available if the network data source is an ArcGIS Online service or the network data source is a service on a version of Portal for ArcGIS that does not support accumulation. | String |
generate_directions_on_solve (Optional) | Specifies whether directions will be generated when running the analysis.
For an analysis in which generating turn-by-turn directions is not needed, use the default option NO_DIRECTIONS to considerably reduce the time it takes to solve the analysis. | Boolean |
Derived Output
| Name | Explanation | Data Type |
| out_network_analysis_layer | The newly created network analysis layer. | Network Analyst Layer |
Code sample
Execute the tool using only the required parameters.
network = "C:/Data/SanFrancisco.gdb/Transportation/Streets_ND"
arcpy.na.MakeClosestFacilityAnalysisLayer(network, "ClosestFireStations")Execute the tool using all parameters.
network = "C:/Data/SanFrancisco.gdb/Transportation/Streets_ND"
arcpy.na.MakeClosestFacilityAnalysisLayer(network, "ClosestHospitals",
"Driving Time", "TO_FACILITIES", 5, 3,
"1/1/1900 9:00 AM", "UTC", "START_TIME",
"ALONG_NETWORK", ["Meters", "TravelTime"])The following stand-alone Python script demonstrates how the MakeClosestFacilityAnalysisLayer tool can be used to find the closest warehouse from the store locations.
# Name: MakeClosestFacilityAnalysisLayer_Workflow.py
# Description: Find the closest warehouse from the store locations and save the
# results to a layer file on disk.
# Requirements: Network Analyst Extension
#Import system modules
import arcpy
from arcpy import env
import os
try:
#Check out Network Analyst license if available. Fail if the Network Analyst license is not available.
if arcpy.CheckExtension("network") == "Available":
arcpy.CheckOutExtension("network")
else:
raise arcpy.ExecuteError("Network Analyst Extension license is not available.")
#Set environment settings
output_dir = "C:/Data"
#The NA layer's data will be saved to the workspace specified here
env.workspace = os.path.join(output_dir, "Output.gdb")
env.overwriteOutput = True
#Set local variables
input_gdb = "C:/Data/Paris.gdb"
network = os.path.join(input_gdb, "Transportation", "ParisMultimodal_ND")
layer_name = "ClosestWarehouse"
travel_mode = "Driving Time"
facilities = os.path.join(input_gdb, "Analysis", "Warehouses")
incidents = os.path.join(input_gdb, "Analysis", "Stores")
output_layer_file = os.path.join(output_dir, layer_name + ".lyrx")
#Create a new closest facility analysis layer.
result_object = arcpy.na.MakeClosestFacilityAnalysisLayer(network,
layer_name, travel_mode, "TO_FACILITIES",
number_of_facilities_to_find=1)
#Get the layer object from the result object. The closest facility layer can
#now be referenced using the layer object.
layer_object = result_object.getOutput(0)
#Get the names of all the sublayers within the closest facility layer.
sublayer_names = arcpy.na.GetNAClassNames(layer_object)
#Stores the layer names that we will use later
facilities_layer_name = sublayer_names["Facilities"]
incidents_layer_name = sublayer_names["Incidents"]
#Load the warehouses as Facilities using the default field mappings and
#search tolerance
arcpy.na.AddLocations(layer_object, facilities_layer_name,
facilities, "", "")
#Load the stores as Incidents. Map the Name property from the NOM field
#using field mappings
field_mappings = arcpy.na.NAClassFieldMappings(layer_object,
incidents_layer_name)
field_mappings["Name"].mappedFieldName = "NOM"
arcpy.na.AddLocations(layer_object, incidents_layer_name, incidents,
field_mappings, "")
#Solve the closest facility layer
arcpy.na.Solve(layer_object)
#Save the solved closest facility layer as a layer file on disk
layer_object.saveACopy(output_layer_file)
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: Yes
- Standard: Yes
- Advanced: Yes