Solve Location-Allocation Tool
How to use Solve Location-Allocation Tool in Arc Toolbox ArcMap ArcGIS??
Solve Location-Allocation
Path to access the tool
:
Solve
Location-Allocation Tool, Server Toolset, Network
Analyst Tools Toolbox
Solve Location-Allocation
Chooses the best 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.
1. Facilities
Specify one or more
facilities. 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:
OBJECTID—The
system-managed ID field.
SHAPE—The geometry field
indicating the geographic location of the facility.
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 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 passengers can disembark at the curb.
- 2 (Left side of vehicle)—Arrive at or depart the facility so 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 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.
2. Demand Points
Specify one or more
demand points. 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:
OBJECTID—The
system-managed ID field.
SHAPE—The geometry field
indicating the geographic location of the facility.
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 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 demand point can be visited from either the right or left side of the vehicle.
- 1 (Input to this tool includes facilities, which provide goods or services, and demand points, which consume the goods and services)—Arrive at or depart the demand point so 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 passengers can disembark at the curb.
- 2 (Left side of vehicle)—Arrive at or depart the demand point so 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 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.
3. 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
The tool chooses whether
to use the network cost attribute specified in the Time Attribute or Distance
Attribute parameter depending on whether the chosen measurement units are time
or distance based.
The tool performs the
necessary unit conversion when the Measurement Units value differs from the
units of the corresponding time or distance cost attribute.
4. Network Dataset
The network dataset on
which the analysis will be performed. Network datasets most often represent
street networks but may represent other kinds of transportation networks as
well. The network dataset needs at least one time-based and one distance-based
cost attribute.
5. Output Geodatabase
The output workspace.
This workspace must already exist. The default output workspace is in_memory.
6. Output Allocation Lines Name
The name of the output
feature class containing the lines that connect demand points to their assigned
facilities.
Output from Solve
Location-Allocation describes the schema of this output feature class.
7. Output Facilities Name
The name of the output
feature class containing the facilities.
Output from Solve
Location-Allocation describes the schema of this output feature class.
8. Output Demand Points Name
The name of the output
feature class containing the demand points.
Output from Solve
Location-Allocation describes the schema of this output feature class.
9. Output Route Edges Name
The name of the output
feature class containing the route edges. Route edges represent the individual
street features that are traversed along the shortest path between the demand
points and the facilities to which they are allocated.
This output is often
used to determine which street segments would experience the most traffic when
traveling to facilities. This information can be used, for example, to place
advertisements or expand roads to support traffic loads during evacuations.
To populate the output RouteEdges
feature class, you need to set the Allocation Line Shape parameter to true
lines.
Output from Solve
Location-Allocation describes the schema of this output feature class.
10. Travel Mode (optional)
Choose the mode of
transportation for the analysis. Custom is always a choice. For other travel
mode names to appear, they must be present in the network dataset specified in
the Network Dataset parameter.
A travel mode is defined on a network dataset and provides override values for parameters that, together, model cars, trucks, pedestrians, or other modes of travel. By choosing a travel mode here, you don't need to provide values for the following parameters, which are overridden by values specified in the network dataset:
- UTurn Policy
- Time Attribute
- Time Attribute Units
- Distance Attribute
- Distance Attribute Units
- Use Hierarchy in Analysis
- Restrictions
- Attribute Parameter Values
- Route Line Simplification Tolerance
- CUSTOM—Define a travel mode that fits your specific needs. When Custom is chosen, the tool does not override the travel mode parameters listed above. This is the default value.
11. Advanced Analysis
12.
Barriers
13.
Custom Travel Mode
14.
Network Dataset
15.
Network Location
16.
Output
17. Service Capabilities
All the seven additional categories are explained in detail, click here to access their explanation
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