SolveLocationAllocation

Summary

The SolveLocationAllocation tool chooses the best location or locations from a set of input locations.

Input to this tool includes facilities, which provide goods or services, and demand points, which consume the goods and services. The objective is to find the facilities that supply the demand points most efficiently. The tool solves this problem by analyzing various ways the demand points can be assigned to the different facilities. The solution is the scenario that allocates the most demand to facilities and minimizes overall travel. The output includes the solution facilities, demand points associated with their assigned facilities, and lines connecting demand points to their facilities.

The location-allocation tool can be configured to solve specific problem types. Examples include the following:

• A retail store wants to see which potential store locations would need to be developed to capture 10 percent of the retail market in the area.

• A fire department wants to determine where it should locate fire stations to reach 90 percent of the community within a four-minute response time.

• A police department wants to preposition personnel given past criminal activity at night.

• After a storm, a disaster response agency wants to find the best locations to set up triage facilities, with limited patient capacities, to tend to the affected population.

Illustration

Usage

• The tool chooses the best facilities based on travel time if the value for the Measurement Units parameter is time based. It's based on travel distance if the measurement units are distance based.

• You need to specify at least one facility and one demand point to successfully execute the tool. You can load up to 1,000 facilities and 10,000 demand points.

• You can add up to 250 point barriers. You can add any number of line or polygon barriers, but line barriers cannot intersect more than 500 street features, and polygon barriers cannot intersect more than 2,000 features.

• You can choose to use the road hierarchy when solving so results are generated faster, but the solution may be somewhat less than optimal.

• Regardless of whether the Use Hierarchy parameter is checked (True), hierarchy is always used when the straight-line distance between any pair of features representing demand points or facilities is greater than 50 miles (80.46 kilometers).

• The straight-line distance between any pair of features representing demand points or facilities cannot be greater than 50 miles (80.46 kilometers) when Travel Mode is set to Walking, or when it is set to Custom and the Walking restriction is used.

• If the distance between an input point and its nearest traversable street is greater than 12.42 miles (20 kilometers), the point is excluded from the analysis.

• This tool is designed to run in ArcGIS Pro, ArcMap, ArcGlobe, and ArcScene, but not in ArcCatalog.

Syntax

SolveLocationAllocation_naagol (Facilities, Demand_Points, {Analysis_Region}, Measurement_Units, {Problem_Type}, {Number_of_Facilities_to_Find}, {Default_Measurement_Cutoff}, {Default_Capacity}, {Target_Market_Share}, {Measurement_Transformation_Model}, {Measurement_Transformation_Factor}, {Travel_Direction}, {Time_of_Day}, {Time_Zone_for_Time_of_Day}, {UTurn_at_Junctions}, {Point_Barriers}, {Line_Barriers}, {Polygon_Barriers}, {Use_Hierarchy}, {Restrictions}, {Attribute_Parameter_Values}, {Allocation_Line_Shape}, {Travel_Mode}, {Impedance})

Parameter	Explanation	Data Type
Facilities	Specify one or more facilities (up to 1,000). The tool chooses the best locations from the set of facilities you specify here. In a competitive analysis, in which you try to find the best locations in the face of competition, the facilities of the competitors are specified here as well. When defining the facilities, you can set properties for each one, such as the facility name or type, by using attributes. Facilities can be specified with the following fields: Name—The name of the facility. The name is included in the name of output allocation lines if the facility is part of the solution. FacilityType—Specifies whether the facility is a candidate, required, or competitor facility. The field value is specified as one of the following integers (use the numeric code, not the name in parentheses): 0 (Candidate)—A facility that may be part of the solution. 1 (Required)—A facility that must be part of the solution. 2 (Competitor)—A rival facility that potentially removes demand from your facilities. Competitor facilities are specific to the Maximize Market Share and Target Market Share problem types; they are ignored in other problem types. Weight—The relative weighting of the facility, which is used to rate the attractiveness, desirability, or bias of one facility compared to another. For example, a value of 2.0 could capture the preference of customers who prefer, at a ratio of 2 to 1, shopping in one facility over another facility. Factors that potentially affect facility weight include square footage, neighborhood, and age of the building. Weight values other than one are only honored by the maximize market share and target market share problem types; they are ignored in other problem types. Capacity—The Capacity field is specific to the Maximize Capacitated Coverage problem type; the other problem types ignore this field. Capacity specifies how much weighted demand the facility is capable of supplying. Excess demand won't be allocated to a facility even if that demand is within the facility's default measurement cutoff. Any value assigned to the Capacity field overrides the Default Capacity parameter (Default_Capacity in Python) for the given facility. CurbApproach—Specifies the direction a vehicle may arrive at or depart from the facility. The field value is specified as one of the following integers (use the numeric code, not the name in parentheses): 0 (Either side of vehicle)—The facility can be visited from either the right or left side of the vehicle. 1 (Right side of vehicle)—Arrive at or depart the facility so that it is on the right side of the vehicle. This is typically used for vehicles such as buses that must arrive with the bus stop on the right-hand side so that passengers can disembark at the curb. 2 (Left side of vehicle)—Arrive at or depart the facility so that it is on the left side of the vehicle. When the vehicle approaches and departs the facility, the curb must be on the left side of the vehicle. This is typically used for vehicles such as buses that must arrive with the bus stop on the left-hand side so that passengers can disembark at the curb. The CurbApproach property is designed to work with both kinds of national driving standards: right-hand traffic (United States) and left-hand traffic (United Kingdom). First, consider a facility on the left side of a vehicle. It is always on the left side regardless of whether the vehicle travels on the left or right half of the road. What may change with national driving standards is your decision to approach a facility from one of two directions, that is, so it ends up on the right or left side of the vehicle. For example, if you want to arrive at a facility and not have a lane of traffic between the vehicle and the incident, you would choose Right side of vehicle (1) in the United States but Left side of vehicle (2) in the United Kingdom.	Feature Set
Demand_Points	Specify one or more demand points (up to 10,000). The tool chooses the best facilities based in large part on how they serve the demand points specified here. When defining the demand points, you can set properties for each one, such as the demand-point name or weight, by using attributes. Demand points can be specified with the following fields: Name—The name of the demand point. The name is included in the name of an output allocation line or lines if the demand point is part of the solution. GroupName—The name of the group the demand point is part of. This property is ignored for the maximize capacitated coverage, target market share, and maximize market share problem types. If demand points share a group name, the solver allocates all members of the group to the same facility. (If constraints, such as a cutoff distance, prevent any of the demand points in the group from reaching the same facility, none of the demand points are allocated.) Weight—The relative weighting of the demand point. A value of 2.0 means the demand point is twice as important as one with a weight of 1.0. If demand points represent households, weight could indicate the number of people in each household. Cutoff_Time—The demand point can't be allocated to a facility that is beyond the travel time indicated here. This field value overrides the value of the Default Measurement Cutoff parameter. The units for this attribute value are specified by the Measurement Units parameter. The attribute value is referenced during the analysis only when the measurement units are time based. The default value is null, which means there isn't an override cutoff. Cutoff_Distance—The demand point can't be allocated to a facility that is beyond the travel distance indicated here. This field value overrides the value of the Default Measurement Cutoff parameter. The units for this attribute value are specified by the Measurement Units parameter. The attribute value is referenced during the analysis only when the measurement units are distance based. The default value is null, which means there isn't an override cutoff. CurbApproach—Specifies the direction a vehicle may arrive at or depart from the demand point. The field value is specified as one of the following integers (use the numeric code, not the name in parentheses): 0 (Either side of vehicle)—The demand point can be visited from either the right or left side of the vehicle. 1 (Right side of vehicle)—Arrive at or depart the demand point so that it is on the right side of the vehicle. This is typically used for vehicles such as buses that must arrive with the bus stop on the right-hand side so that passengers can disembark at the curb. 2 (Left side of vehicle)—Arrive at or depart the demand point so that it is on the left side of the vehicle. When the vehicle approaches and departs the demand point, the curb must be on the left side of the vehicle. This is typically used for vehicles such as buses that must arrive with the bus stop on the left-hand side so that passengers can disembark at the curb. The CurbApproach property is designed to work with both kinds of national driving standards: right-hand traffic (United States) and left-hand traffic (United Kingdom). First, consider a demand point on the left side of a vehicle. It is always on the left side regardless of whether the vehicle travels on the left or right half of the road. What may change with national driving standards is your decision to approach a demand point from one of two directions, that is, so it ends up on the right or left side of the vehicle. For example, if you want to arrive at a demand point and not have a lane of traffic between the vehicle and the demand point, you would choose Right side of vehicle (1) in the United States but Left side of vehicle (2) in the United Kingdom.	Feature Set
Analysis_Region (Optional)	Specify the region in which to perform the analysis. If a value is not specified for this parameter, the tool will automatically calculate the region name based on the location of the input points. Setting the name of the region is recommended to speed up the tool execution. To specify a region, use one of the following values: Europe Greece India Japan Korea MiddleEastAndAfrica NorthAmerica Oceania SouthAmerica SouthEastAsia Taiwan Thailand	String
Measurement_Units	Specify the units that should be used to measure the travel times or travel distances between demand points and facilities. The tool chooses the best facilities based on which ones can reach, or be reached by, the most amount of weighted demand with the least amount travel. The output allocation lines report travel distance or travel time in different units, including the units you specify for this parameter. The choices are Meters Kilometers Feet Yards Miles NauticalMiles Seconds Minutes Hours Days	String
Problem_Type (Optional)	Specifies the objective of the location-allocation analysis. The default objective is to minimize impedance. Minimize Impedance: This is also known as the P-Median problem type. Facilities are located such that the sum of all weighted travel time or distance between demand points and solution facilities is minimized. (Weighted travel is the amount of demand allocated to a facility multiplied by the travel distance or time to the facility.) This problem type is traditionally used to locate warehouses, because it can reduce the overall transportation costs of delivering goods to outlets. Since Minimize Impedance reduces the overall distance the public needs to travel to reach the chosen facilities, the minimize impedance problem without an impedance cutoff is ordinarily regarded as more equitable than other problem types for locating some public-sector facilities such as libraries, regional airports, museums, department of motor vehicles offices, and health clinics. The following list describes how the minimize impedance problem type handles demand: A demand point that cannot reach any facilities, due to setting a cutoff distance or time, is not allocated. A demand point that can only reach one facility has all its demand weight allocated to that facility. A demand point that can reach two or more facilities has all its demand weight allocated to the nearest facility only. Maximize Coverage: Facilities are located such that as much demand as possible is allocated to solution facilities within the impedance cutoff. Maximize Coverage is frequently used to locate fire stations, police stations, and ERS centers, because emergency services are often required to arrive at all demand points within a specified response time. Note that it is important for all organizations, and critical for emergency services, to have accurate and precise data so that analysis results correctly model real-world results. Pizza delivery businesses, as opposed to eat-in pizzerias, try to locate stores where they can cover the most people within a certain drive time. People who order pizzas for delivery don't typically worry about how far away the pizzeria is; they are mainly concerned with the pizza arriving within an advertised time window. Therefore, a pizza-delivery business would subtract pizza-preparation time from their advertised delivery time and solve a maximize coverage problem to choose the candidate facility that would capture the most potential customers in the coverage area. (Potential customers of eat-in pizzerias are more affected by distance, since they need to travel to the restaurant; thus, the attendance maximizing or market share problem types would better suit eat-in restaurants.) The following list describes how the Maximize Coverage problem handles demand: A demand point that cannot reach any facilities due to cutoff distance or time is not allocated. A demand point that can only reach one facility has all its demand weight allocated to that facility. A demand point that can reach two or more facilities has all its demand weight allocated to the nearest facility only. Maximize Capacitated Coverage: Facilities are located such that all or the greatest amount of demand can be served without exceeding the capacity of any facility. Maximize Capacitated Coverage behaves like either the Minimize Impedance or Maximize Coverage problem type but with the added constraint of capacity. You can specify a capacity for an individual facility by assigning a numeric value to its corresponding Capacity field on the input facilities. If the Capacity field value is null, the facility is assigned a capacity from the Default Capacity property. Use-cases for Maximize Capacitated Coverage include creating territories that encompass a given number of people or businesses, locating hospitals or other medical facilities with a limited number of beds or patients who can be treated, or locating warehouses whose inventory isn't assumed to be unlimited. The following list describes how the Maximize Capacitated Coverage problem handles demand: Unlike Maximize Coverage, Maximize Capacitated Coverage doesn't require a value for the Default Measurement Cutoff; however, when an cutoff is specified, any demand point outside the cutoff time or distance of all facilities is not allocated. An allocated demand point has all or none of its demand weight assigned to a facility; that is, demand isn't apportioned with this problem type. If the total demand that can reach a facility is greater than the capacity of the facility, only the demand points that maximize total captured demand and minimize total weighted travel are allocated. Note: You may notice an apparent inefficiency when a demand point is allocated to a facility that isn't the nearest solution facility. This may occur when demand points have varying weights and when the demand point in question can reach more than one facility. This kind of result indicates the nearest solution facility didn't have adequate capacity for the weighted demand, or the most efficient solution for the entire problem required one or more local inefficiencies. In either case, the solution is correct. Minimize Facilities: Facilities are chosen such that as much weighted demand as possible are allocated to solution facilities within the travel time or distance cutoff; additionally, the number of facilities required to cover demand is minimized. Minimize Facilities is the same as Maximize Coverage but with the exception of the number of facilities to locate, which in this case is determined by the solver. When the cost of building facilities is not a limiting factor, the same kinds of organizations that use Maximize Coverage (emergency response, for instance) use Minimize Facilities so that all possible demand points will be covered. The following list describes how the Minimize Facilities problem handles demand: A demand point that cannot reach any facilities due to a cutoff distance or time is not allocated. A demand point that can only reach one facility has all its demand weight allocated to that facility. A demand point that can reach two or more facilities has all its demand weight allocated to the nearest facility only. Maximize Attendance: Facilities are chosen such that as much demand weight as possible is allocated to facilities while assuming the demand weight decreases in relation to the distance between the facility and the demand point. Specialty stores that have little or no competition benefit from this problem type, but it may also be beneficial to general retailers and restaurants that don't have the data on competitors necessary to perform market share problem types. Some businesses that might benefit from this problem type include coffee shops, fitness centers, dental and medical offices, and electronics stores. Public transit bus stops are often chosen with the help of Maximize Attendance. Maximize Attendance assumes that the farther people have to travel to reach your facility, the less likely they are to use it. This is reflected in how the amount of demand allocated to facilities diminishes with distance. The following list describes how the Maximize Attendance problem handles demand: A demand point that cannot reach any facilities due to a cutoff distance or time is not allocated. When a demand point can reach a facility, its demand weight is only partially allocated to the facility. The amount allocated decreases as a function of the maximum cutoff distance (or time) and the travel distance (or time) between the facility and the demand point. The weight of a demand point that can reach more than one facility is proportionately allocated to the nearest facility only. Maximize Market Share: A specific number of facilities are chosen such that the allocated demand is maximized in the presence of competitors. The goal is to capture as much of the total market share as possible with a given number of facilities, which you specify. The total market share is the sum of all demand weight for valid demand points. The market share problem types require the most data because, along with knowing your own facilities' weight, you also need to know that of your competitors' facilities. The same types of facilities that use the Maximize Attendance problem type can also use market share problem types given that they have comprehensive information that includes competitor data. Large discount stores typically use Maximize Market Share to locate a finite set of new stores. The market share problem types use a Huff model, which is also known as a gravity model or spatial interaction. The following list describes how the Maximize Market Share problem handles demand: A demand point that cannot reach any facilities due to a cutoff distance or time is not allocated. A demand point that can only reach one facility has all its demand weight allocated to that facility. A demand point that can reach two or more facilities has all its demand weight allocated to them; furthermore, the weight is split among the facilities proportionally to the facilities' attractiveness (facility weight) and inversely proportional to the distance between the facility and demand point. Given equal facility weights, this means more demand weight is assigned to near facilities than far facilities. The total market share, which can be used to calculate the captured market share, is the sum of the weight of all valid demand points. Target Market Share: Target Market Share chooses the minimum number of facilities necessary to capture a specific percentage of the total market share in the presence of competitors. The total market share is the sum of all demand weight for valid demand points. You set the percent of the market share you want to reach and let the solver choose the fewest number of facilities necessary to meet that threshold. The market share problem types require the most data because, along with knowing your own facilities' weight, you also need to know that of your competitors' facilities. The same types of facilities that use the Maximize Attendance problem type can also use market share problem types given that they have comprehensive information that includes competitor data. Large discount stores typically use the Target Market Share problem type when they want to know how much expansion would be required to reach a certain level of the market share or see what strategy would be needed just to maintain their current market share given the introduction of new competing facilities. The results often represent what stores would like to do if budgets weren't a concern. In other cases where budget is a concern, stores revert to the Maximize Market Share problem and simply capture as much of the market share as possible with a limited number of facilities. The following list describes how the target market share problem handles demand: The total market share, which is used in calculating the captured market share, is the sum of the weight of all valid demand points. A demand point that cannot reach any facilities due to a cutoff distance or time is not allocated. A demand point that can only reach one facility has all its demand weight allocated to that facility. A demand point that can reach two or more facilities has all its demand weight allocated to them; furthermore, the weight is split among the facilities proportionally to the facilities' attractiveness (facility weight) and inversely proportional to the distance between the facility and demand point. Given equal facility weights, this means more demand weight is assigned to near facilities than far facilities.	String
Number_of_Facilities_to_Find (Optional)	Specify the number of facilities the solver should choose. The default value is 1. The facilities with a FacilityType field value of 1 (Required) are always chosen first. Any excess facilities to choose are picked from candidate facilities, which have a FacilityType field value of 2. Any facilities that have a FacilityType value of 3 (Chosen) before solving are treated as candidate facilities at solve time. If the number of facilities to find is less than the number of required facilities, an error occurs. Number of Facilities to Find is disabled for the Minimize Facilities and Target Market Share problem types since the solver determines the minimum number of facilities needed to meet the objectives.	Long
Default_Measurement_Cutoff (Optional)	Specifies the maximum travel time or distance allowed between a demand point and the facility it is allocated to. If a demand point is outside the cutoff of a facility, it cannot be allocated to that facility. The default value is none, which means the cutoff limit doesn't apply. The units for this parameter are the same as those specified by the Measurement Units parameter. The travel time or distance cutoff is measured by the shortest path along roads. This property might be used to model the maximum distance that people are willing to travel to visit stores or the maximum time that is permitted for a fire department to reach anyone in the community. Note that demand points have Cutoff_Time and Cutoff_Distance fields, which, if set accordingly, overrides the Default Measurement Cutoff parameter. You might find that people in rural areas are willing to travel up to 10 miles to reach a facility while urbanites are only willing to travel up to two miles. Assuming Measurement Units is set to Miles, you can model this behavior by setting the default measurement cutoff to 10 and the Cutoff_Distance field value of the demand points in urban areas to 2.	Double
Default_Capacity (Optional)	This property is specific to the Maximize Capacitated Coverage problem type. It is the default capacity assigned to all facilities in the analysis. You can override the default capacity for a facility by specifying a value in the facility's Capacity field. The default value is 1.	Double
Target_Market_Share (Optional)	This parameter is specific to the Target Market Share problem type. It is the percentage of the total demand weight that you want the chosen and required facilities to capture. The solver chooses the minimum number of facilities needed to capture the target market share specified here. The default value is 10 percent.	Double
Measurement_Transformation_Model (Optional)	This sets the equation for transforming the network cost between facilities and demand points. This property, coupled with the Impedance Parameter, specifies how severely the network impedance between facilities and demand points influences the solver's choice of facilities. In the following list of transformation options, d refers to demand points and f, facilities. "Impedance" refers to the shortest travel distance or time between two locations. So impedancedf is the shortest-path (time or distance) between demand point d and facility f, and costdf is the transformed travel time or distance between the facility and demand point. Lambda (λ) denotes the impedance parameter. The Measurement Units setting determines whether travel time or distance is analyzed. Linear: costdf = λ * impedancedf The transformed travel time or distance between the facility and the demand point is the same as the time or distance of the shortest path between the two locations. With this option, the impedance parameter (λ) is always set to one. This is the default. Power: costdf = impedancedf^λ The transformed travel time or distance between the facility and the demand point is equal to the time or distance of the shortest path raised to the power specified by the impedance parameter (λ). Use the Power option with a positive impedance parameter to specify higher weight to nearby facilities. Exponential: costdf = e^(λ * impedancedf) The transformed travel time or distance between the facility and the demand point is equal to the mathematical constant e raised to the power specified by the shortest-path network impedance multiplied with the impedance parameter (λ). Use the Exponential option with a positive impedance parameter to specify a high weight to nearby facilities.	String
Measurement_Transformation_Factor (Optional)	Provides a parameter value to the equations specified in the Measurement Transformation Model parameter. The parameter value is ignored when the impedance transformation is of type linear. For power and exponential impedance transformations, the value should be nonzero. The default value is 1.	Double
Travel_Direction (Optional)	Specify whether to measure travel times or distances from facilities to demand points or from demand points to facilities. The default value is to measure from facilities to demand points. Facility to Demand: Direction of travel is from facilities to demand points. This is the default. Demand to Facility: Direction of travel is from demand points to facilities. Travel times and distances may change based on direction of travel. If going from point A to point B, you may encounter less traffic or have a shorter path, due to one-way streets and turn restrictions, than if you were traveling in the opposite direction. For instance, going from point A to point B may only take 10 minutes, but going the other direction may take 15 minutes. These differing measurements may affect whether demand points can be assigned to certain facilities because of cutoffs or, in problem types where demand is apportioned, affect how much demand is captured. Fire departments commonly measure from facilities to demand points since they are concerned with the time it takes to travel from the fire station to the location of the emergency. A retail store is more concerned with the time it takes shoppers to reach the store; therefore, stores commonly measure from demand points to facilities. Travel Direction also determines the meaning of any start time that is provided. See the Time of Day parameter for more information.	String
Time_of_Day (Optional)	Specify the time at which travel begins. This property is ignored unless Measurement Units are time based. The default is no time or date. When Time of Day isn't specified, the solver uses generic speeds—typically those from posted speed limits. Traffic constantly changes in reality, and as it changes, travel times between facilities and demand points also fluctuate. Therefore, indicating different time and date values over several analyses may affect how demand is allocated to facilities and which facilities are chosen in the results. The time of day always indicates a start time. However, travel may start from facilities or demand points; it depends on what you choose for the Travel Direction parameter. The Time Zone for Time of Day parameter specifies whether this time and date refer to UTC or the time zone in which the facility or demand point is located.	Date
Time_Zone_for_Time_of_Day (Optional)	Specifies the time zone of the Time of Day parameter. The default is geographically local. Geographically Local: The Time of Day parameter refers to the time zone in which the facilities or demand points are located. If Travel Direction is facilities to demand points, this is the time zone of the facilities. If Travel Direction is demand points to facilities, this is the time zone of the demand points. UTC: The Time of Day parameter refers to Coordinated Universal Time (UTC). Choose this option if you want to choose the best location for a specific time, such as now, but aren't certain in which time zone the facilities or demand points will be located. Irrespective of the Time Zone for Time of Day setting, the following rules are enforced by the tool if your facilities and demand points are in multiple time zones: All facilities must be in the same time zone when specifying a time of day and travel is from facility to demand. All demand points must be in the same time zone when specifying a time of day and travel is from demand to facility.	String
UTurn_at_Junctions (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, or streets, 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. Allowed: U-turns are permitted at junctions with any number of connected edges, or streets. This is the default value. Not Allowed: U-turns are prohibited at all junctions, regardless of junction valency. Allowed only at Dead Ends: U-turns are prohibited at all junctions, except those that have only one adjacent edge (a dead end). Allowed only at Intersections and Dead Ends: 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 modeling streets have extraneous junctions in the middle of road segments. This option prevents vehicles from making U-turns at these locations. This parameter is ignored unless Travel Mode is set to Custom.	String
Point_Barriers (Optional)	Specify one or more points to act as temporary restrictions or represent additional time or distance that may be required to travel on the underlying streets. For example, a point barrier can be used to represent a fallen tree along a street or time delay spent at a railroad crossing. The tool imposes a limit of 250 points that can be added as barriers. When specifying the point barriers, you can set properties for each one, such as its name or barrier type, by using attributes. The point barriers can be specified with the following attributes: Name: The name of the barrier. BarrierType: Specifies whether the point barrier restricts travel completely or adds time or distance when it is crossed. The value for this attribute is specified as one of the following integers (use the numeric code, not the name in parentheses): 0 (Restriction)—Prohibits travel through the barrier. The barrier is referred to as a restriction point barrier since it acts as a restriction. 2 (Added Cost)—Traveling through the barrier increases the travel time or distance by the amount specified in the Additional_Time or Additional_Distance field. This barrier type is referred to as an added-cost point barrier. Additional_Time: Indicates how much travel time is added when the barrier is traversed. This field is applicable only for added-cost barriers and only if the measurement units are time based. This field value must be greater than or equal to zero, and its units are the same as those specified in the Measurement Units parameter. Additional_Distance: Indicates how much distance is added when the barrier is traversed. This field is applicable only for added-cost barriers and only if the measurement units are distance based. The field value must be greater than or equal to zero, and its units are the same as those specified in the Measurement Units parameter.	Feature Set
Line_Barriers (Optional)	Specify one or more lines that prohibit travel anywhere the lines intersect the streets. For example, a parade or protest that blocks traffic across several street segments can be modeled with a line barrier. A line barrier can also quickly fence off several roads from being traversed, thereby channeling possible routes away from undesirable parts of the street network. The tool imposes a limit on the number of streets you can restrict using the Line Barriers parameter. While there is no limit on the number of lines you can specify as line barriers, the combined number of streets intersected by all the lines cannot exceed 500. When specifying the line barriers, you can set a name property for each one by using the following attribute: Name: The name of the barrier.	Feature Set
Polygon_Barriers (Optional)	Specify polygons that either completely restrict travel or proportionately scale the time or distance required to travel on the streets intersected by the polygons. The service imposes a limit on the number of streets you can restrict using the Polygon Barriers parameter. While there is no limit on the number of polygons you can specify as the polygon barriers, the combined number of streets intersected by all the polygons should not exceed 2,000. When specifying the polygon barriers, you can set properties for each one, such as its name or barrier type, by using attributes. The polygon barriers can be specified with the following attributes: Name: The name of the barrier. BarrierType: Specifies whether the barrier restricts travel completely or scales the time or distance for traveling through it. The field value is specified as one of the following integers (use the numeric code, not the name in parentheses): 0 (Restriction)—Prohibits traveling through any part of the barrier. The barrier is referred to as a restriction polygon barrier since it prohibits traveling on streets intersected by the barrier. One use of this type of barrier is to model floods covering areas of the street that make traveling on those streets impossible. 1 (Scaled Cost)—Scales the time or distance required to travel the underlying streets by a factor specified using the ScaledTimeFactor or ScaledDistanceFactor fields. If the streets are partially covered by the barrier, the travel time or distance is apportioned and then scaled. For example, a factor 0.25 would mean that travel on underlying streets is expected to be four times faster than normal. A factor of 3.0 would mean it is expected to take three times longer than normal to travel on underlying streets. This barrier type is referred to as a scaled-cost polygon barrier. It might be used to model storms that reduce travel speeds in specific regions. ScaledTimeFactor: This is the factor by which the travel time of the streets intersected by the barrier is multiplied. This field is applicable only for scaled-cost barriers and only if the measurement units are time based. The field value must be greater than zero. ScaledDistanceFactor: This is the factor by which the distance of the streets intersected by the barrier is multiplied. This attribute is applicable only for scaled-cost barriers and only if the measurement units are distance based. The attribute value must be greater than zero.	Feature Set
Use_Hierarchy (Optional)	Specify whether hierarchy should be used when finding the shortest path between the facilities and demand points. Checked (True): Use hierarchy when measuring between facilities and demand points. When hierarchy is used, the tool prefers higher-order streets (such as freeways) to lower-order streets (such as local roads), and can be used to simulate the driver preference of traveling on freeways instead of local roads even if that means a longer trip. This is especially true when finding routes to faraway locations, because drivers on long-distance trips tend to prefer traveling on freeways where stops, intersections, and turns can be avoided. Using hierarchy is computationally faster, especially for long-distance routes, since the tool can determine the best route from a relatively smaller subset of streets. Unchecked (False): Do not use hierarchy when measuring between facilities and demand points. If hierarchy is not used, the tool considers all the streets and doesn't prefer higher-order streets when finding the route. This is often used when finding short-distance routes within a city. The tool automatically reverts to using hierarchy if the straight-line distance between facilities and demand points is greater than 50 miles, even if you have set this parameter to not use hierarchy.	Boolean
Restrictions (Optional)	Specify which restrictions should be honored by the tool when finding the best routes between facilities and demand points. A restriction represents a driving preference or requirement. In most cases, restrictions cause roads to be prohibited. For instance, using an Avoid Toll Roads restriction will result in a route that will include toll roads only when it is absolutely required to travel on toll roads in order to visit an incident or a facility. Height Restriction makes it possible to route around any clearances that are lower than the height of your vehicle. If you are carrying corrosive materials on your vehicle, using the Any Hazmat Prohibited restriction prevents hauling the materials along roads where it is marked as illegal to do so. Below is a list of available restrictions and a short description. Note: Some restrictions require an additional value to be specified for their desired use. This value needs to be associated with the restriction name and a specific parameter intended to work with the restriction. You can identify such restrictions if their names appear under the AttributeName column in the Attribute Parameter Values parameter. The ParameterValue field should be specified in the Attribute Parameter Values parameter for the restriction to be correctly used when finding traversable roads. Note: Some restrictions are supported only in certain countries; their availability is stated by region in the list below. Of the restrictions that have limited availability within a region, you can check whether the restriction is available in a particular country by looking at the table in the Country List section of the Data coverage for network analysis services web page. If a country has a value of Yes in the Logistics Attribute column, the restriction with select availability in the region is supported in that country. If you specify restriction names that are not available in the country where your incidents are located, the service ignores the invalid restrictions. The service also ignores restrictions whose Restriction Usage parameter value is between 0 and 1 (see the Attribute Parameter Value parameter). It prohibits all restrictions whose Restriction Usage parameter value is greater than 0. The tool supports the following restrictions: Any Hazmat Prohibited—The results will not include roads where transporting any kind of hazardous material is prohibited. Availability: Select countries in North America and Europe Avoid Carpool Roads—The results will avoid roads that are designated exclusively for carpool (high-occupancy) vehicles. Availability: All countries Avoid Express Lanes—The results will avoid roads designated as express lanes. Availability: All countries Avoid Ferries—The results will avoid ferries. Availability: All countries Avoid Gates—The results will avoid roads where there are gates such as keyed access or guard-controlled entryways. Availability: All countries Avoid Limited Access Roads—The results will avoid roads that are limited access highways. Availability: All countries Avoid Private Roads—The results will avoid roads that are not publicly owned and maintained. Availability: All countries Avoid Toll Roads—The results will avoid toll roads. Availability: All countries Avoid Unpaved Roads—The results will avoid roads that are not paved (for example, dirt, gravel, and so on). Availability: All countries Axle Count Restriction—The results will not include roads where trucks with the specified number of axles are prohibited. The number of axles can be specified using the Number of Axles restriction parameter. Availability: Select countries in North America and Europe Driving a Bus—The results will not include roads where buses are prohibited. Using this restriction will also ensure that the results will honor one-way streets. Availability: All countries Driving a Delivery Vehicle—The results will not include roads where delivery vehicles are prohibited. Using this restriction will also ensure that the results will honor one-way streets. Availability: All countries Driving a Taxi—The results will not include roads where taxis are prohibited. Using this restriction will also ensure that the results will honor one-way streets. Availability: All countries Driving a Truck—The results will not include roads where trucks are prohibited. Using this restriction will also ensure that the results will honor one-way streets. Availability: All countries Driving an Automobile—The results will not include roads where automobiles are prohibited. Using this restriction will also ensure that the results will honor one-way streets. Availability: All countries Driving an Emergency Vehicle—The results will not include roads where emergency vehicles are prohibited. Using this restriction will also ensure that the results will honor one-way streets. Availability: All countries Height Restriction—The results will not include roads where the vehicle height exceeds the maximum allowed height for the road. The vehicle height can be specified using the Vehicle Height (meters) restriction parameter. Availability: Select countries in North America and Europe Kingpin to Rear Axle Length Restriction—The results will not include roads where the vehicle length exceeds the maximum allowed kingpin to rear axle for all trucks on the road. The length between the vehicle kingpin and the rear axle can be specified using the Vehicle Kingpin to Rear Axle Length (meters) restriction parameter. Availability: Select countries in North America and Europe Length Restriction—The results will not include roads where the vehicle length exceeds the maximum allowed length for the road. The vehicle length can be specified using the Vehicle Length (meters) restriction parameter. Availability: Select countries in North America and Europe Riding a Motorcycle—The results will not include roads where motorcycles are prohibited. Using this restriction will also ensure that the results will honor one-way streets. Availability: All countries Roads Under Construction Prohibited—The results will not include roads that are under construction. Availability: All countries Semi or Tractor with One or More Trailers Prohibited—The results will not include roads where semis or tractors with one or more trailers are prohibited. Availability: Select countries in North America and Europe Single Axle Vehicles Prohibited—The results will not include roads where vehicles with single axles are prohibited. Availability: Select countries in North America and Europe Tandem Axle Vehicles Prohibited—The results will not include roads where vehicles with tandem axles are prohibited. Availability: Select countries in North America and Europe Through Traffic Prohibited—The results will not include roads where through traffic (non local) is prohibited. Availability: All countries Truck with Trailers Restriction—The results will not include roads where trucks with the specified number of trailers on the truck are prohibited. The number of trailers on the truck can be specified using the Number of Trailers on Truck restriction parameter. Availability: Select countries in North America and Europe Use Preferred Hazmat Routes—The results will prefer roads that are designated for transporting any kind of hazardous materials. Availability: Select countries in North America and Europe Use Preferred Truck Routes—The results will prefer roads that are designated as truck routes, such as the roads that are part of the national network as specified by the National Surface Transportation Assistance Act in the United States, or roads that are designated as truck routes by the state or province, or roads that are preferred by the trucks when driving in an area. Availability: Select countries in North America and Europe Walking—The results will not include roads where pedestrians are prohibited. Availability: All countries Weight Restriction—The results will not include roads where the vehicle weight exceeds the maximum allowed weight for the road. The vehicle weight can be specified using the Vehicle Weight (kilograms) restriction parameter. Availability: Select countries in North America and Europe Weight per Axle Restriction—The results will not include roads where the vehicle weight per axle exceeds the maximum allowed weight per axle for the road. The vehicle weight per axle can be specified using the Vehicle Weight per Axle (kilograms) restriction parameter. Availability: Select countries in North America and Europe Width Restriction—The results will not include roads where the vehicle width exceeds the maximum allowed width for the road. The vehicle width can be specified using the Vehicle Width (meters) restriction parameter. Availability: Select countries in North America and Europe	String
Attribute_Parameter_Values (Optional)	Specify additional values required by some restrictions, such as the weight of a vehicle for Weight Restriction. You can also use the attribute parameter to specify whether any restriction prohibits, avoids, or prefers travel on roads that use the restriction. If the restriction is meant to avoid or prefer roads, you can further specify the degree to which they are avoided or preferred using this parameter. For example, you can choose to never use toll roads, avoid them as much as possible, or even highly prefer them. Note: The values you provide for this parameter are ignored unless Travel Mode is set to Custom. If you specify the Attribute Parameter Values parameter from a feature class, the field names on the feature class must match the fields as described below: AttributeName: Lists the name of the restriction. ParameterName: Lists the name of the parameter associated with the restriction. A restriction can have one or more ParameterName field values based on its intended use. ParameterValue: The value for ParameterName used by the tool when evaluating the restriction. Attribute Parameter Values is dependent on the Restrictions parameter. The ParameterValue field is applicable only if the restriction name is specified as the value for the Restrictions parameter. In Attribute Parameter Values, each restriction (listed as AttributeName) has a ParameterName field value, Restriction Usage, that specifies whether the restriction prohibits, avoids, or prefers travel on the roads associated with the restriction and the degree to which the roads are avoided or preferred. The Restriction Usage ParameterName can be assigned any of the following string values or their equivalent numeric values listed within the parentheses: PROHIBITED (-1)—Travel on the roads using the restriction is completely prohibited. AVOID_HIGH (5)—It is highly unlikely for the tool to include in the route the roads that are associated with the restriction. AVOID_MEDIUM (2)—It is unlikely for the tool to include in the route the roads that are associated with the restriction. AVOID_LOW (1.3)—It is somewhat unlikely for the tool to include in the route the roads that are associated with the restriction. PREFER_LOW (0.8)—It is somewhat likely for the tool to include in the route the roads that are associated with the restriction. PREFER_MEDIUM (0.5)—It is likely for the tool to include in the route the roads that are associated with the restriction. PREFER_HIGH (0.2)—It is highly likely for the tool to include in the route the roads that are associated with the restriction. In most cases, you can use the default value, PROHIBITED, for the Restriction Usage if the restriction is dependent on a vehicle-characteristic such as vehicle height. However, in some cases, the value for Restriction Usage depends on your routing preferences. For example, the Avoid Toll Roads restriction has the default value of AVOID_MEDIUM for the Restriction Usage parameter. This means that when the restriction is used, the tool will try to route around toll roads when it can. AVOID_MEDIUM also indicates how important it is to avoid toll roads when finding the best route; it has a medium priority. Choosing AVOID_LOW would put lower importance on avoiding tolls; choosing AVOID_HIGH instead would give it a higher importance and thus make it more acceptable for the service to generate longer routes to avoid tolls. Choosing PROHIBITED would entirely disallow travel on toll roads, making it impossible for a route to travel on any portion of a toll road. Keep in mind that avoiding or prohibiting toll roads, and thus avoiding toll payments, is the objective for some; in contrast, others prefer to drive on toll roads because avoiding traffic is more valuable to them than the money spent on tolls. In the latter case, you would choose PREFER_LOW, PREFER_MEDIUM, or PREFER_HIGH as the value for Restriction Usage. The higher the preference, the farther the tool will go out of its way to travel on the roads associated with the restriction.	Record Set
Allocation_Line_Shape (Optional)	The default is to output straight lines. Specify the type of line features that are output by the tool. The parameter accepts one of the following values: Straight Line: Return straight lines between solution facilities and the demand points allocated to them. This is the default. Drawing straight lines on a map helps you visualize how demand is allocated. None: Return a table containing data about the shortest paths between solution facilities and the demand points allocated to them, but don't return lines. No matter which value you choose for the Allocation Line Shapeparameter, the shortest route is always determined by minimizing the travel time or the travel distance, never using the straight-line distance between demand points and facilities. That is, this parameter only changes the output line shapes; it doesn't change the measurement method.	String
Travel_Mode (Optional)	Choose the mode of transportation to model in the analysis. Driving—Models traveling by car. It obeys one-way roads, avoids illegal turns, and follows other rules specific to cars. Dynamic travel speeds based on traffic are used where it is available. Trucking—Models basic truck travel by prefering designated truck routes and using typical truck speeds. It also obeys one-way roads, avoids illegal turns, and so on. To model the characteristics of a specific truck, such as its height and weight, choose the Custom travel mode instead. Walking—Follows paths and roads that allow pedestrian traffic. Custom—This is the default value. Allows you to configure your own travel mode using the custom travel mode parameters (UTurn at Junctions, Use Hierarchy, Restrictions, Attribute Parameter Values, and Impedance). The default values of the custom travel mode parameters model traveling by car. You may want to choose Custom and set the custom travel mode parameters listed above to model a pedestrian with a fast walking speed or a truck with a given height, weight, and cargo of certain hazardous materials. By choosing Custom, the values you set for the custom travel mode parameters are included in the analysis. (Choosing another travel mode—Driving, Trucking, or Walking—causes any values you set for the custom travel mode parameters to be ignored; the tool overrides them with values that model a typical car, truck, or pedestrian.) For modeling a custom truck mode, you would follow the steps listed below. Choose Custom for Travel Mode. Check (or set to True) Driving a Truck in the Restrictions parameter. Check all other restrictions that will help you model your truck. Set values for Attribute Parameter Values. This is where you can set the dimensions of your vehicle, including the height, weight, and length, and special values for restrictions you checked in the last step. You might also want to change whether those restrictions are prohibited (roads with the restriction are never traveled on), avoided (roads with the restriction are avoided as long as the detour to avoid them is not too far out of the way), or preferred (roads with the restriction are preferred as long as the detour to travel on them is not too far out of the way). Set UTurn at Junctions and Use Hierarchy. Set Impedance to Truck Time or Travel Distance. For modeling a pedestrian with specific routing requirements, you would follow the same procedure as setting up a custom truck mode, but with the following differences: Check (or set to True) the Walking restriction (and uncheck Driving a Truck). Check other restrictions, such as Avoid Stairways. Uncheck others. If necessary, set relevant attribute parameters, such as the the walking speed, in Attribute Parameter Values. Set UTurn at Junctions to Allowed. Uncheck (or set to False) Use Hierarchy. Set Impedance to Walk Time or Travel Distance.	String
Impedance (Optional)	Specify the impedance, which is a value that represents the effort or cost of traveling along road segments or on other parts of the transportation network. Travel distance is an impedance; the length of a road in kilometers can be thought of as impedance. Travel distance in this sense is the same for all modes—a kilometer for a pedestrian is also a kilometer for a car. (What may change is the pathways on which the different modes are allowed to travel, which affects distance between points, and this is modeled by travel mode settings.) Travel time can also be an impedance; a car may take one minute to travel a mile along an empty road. Travel times can vary by travel mode—a pedestrian may take more than 20 minutes to walk the same mile, so it is important to choose the right impedance for the travel mode you are modeling. Choose from the following impedance values: Drive Time—Models travel times for a car. These travel times are dynamic and fluctuate according to traffic flows in areas where traffic data is available. This is the default value. Truck Time—Models travel times for a truck. These travel times are static for each road and don't fluctuate with traffic. Walk Time—Models travel times for a pedestrian. Travel Distance—Stores length measurements along roads and paths. To model walk distance, choose this option and ensure Walking is set in the Restriction parameter. Similarly, to model drive or truck distance, choose Travel Distance here and set the appropriate restrictions so your vehicle travels only on roads where it is permitted to do so. The value you provide for this parameter is ignored unless Travel Mode is set to Custom, which is the default value. If you choose Drive Time, Truck Time, or Walk Time, the Measurement Units parameter must be set to a time-based value; if you choose Travel Distance for Impedance, Measurement Units must be distance-based.	String

Code sample

Solve Location-Allocation example

The following Python script demonstrates how to use the SolveLocationAllocation tool in a script.

import arcpy
import time
import sys

username = "<your user name>"
password = "<your password>"
LA_service = "http://logistics.arcgis.com/arcgis/services;World/LocationAllocation;{0};{1}".format(username, password)

#Add the geoprocessing service as a toolbox. Use an alias when importing
arcpy.ImportToolbox(LA_service, "agol")

#Set the variables to call the tool
facilities = r'C:/data/Inputs.gdb/Stores'
demandPoints = r'C:/data/Inputs.gdb/Customers'
output_lines = r'C:/data/Results.gdb/Lines'
output_facilities = r'C:/data/Results.gdb/Facilities'
output_demandPoints = r'C:/data/Results.gdb/DemandPoints'

#Call the tool
result = arcpy.agol.SolveLocationAllocation(facilities, demandPoints, "Minutes",
                                            Problem_Type="Maximize Attendance",
                                            Number_of_Facilities_to_Find=2,
                                            Default_Measurement_Cutoff=10.0)

#Check the status of the result object every 0.5 seconds 
#until it has a value of 4(succeeded) or greater 
while result.status < 4:
    time.sleep(0.5)

#print any warning or error messages returned from the tool
result_severity = result.maxSeverity
if result_severity == 2:
    print "An error occured when running the tool"
    print result.getMessages(2)
    sys.exit(2)
elif result_severity == 1:
    print "Warnings were returned when running the tool"
    print result.getMessages(1)
    
#Get the output routes  and save to a local geodatabase
result.getOutput(1).save(output_lines)
result.getOutput(2).save(output_facilities)
result.getOutput(3).save(output_demandPoints)

Environments

This tool does not use any geoprocessing environments