.set(+)

Traditional static traffic assignment method

Description

This .set allows you to set the choice for components used in traditional static assigment such as:

  • How to compute cost for the transport network (split in physical and virtual cost)
  • How to perform smoothing between iterations

Depending on the chosen option the assignment performs differently

Signature

.set(component_type_enum_choice)

Parameter Type Unit Compulsory Description
component_type_enum_choice PhysicalCost.<enum> - YES Type of link performance function to apply as the physical cost, i.e., travel time
"” VirtualCost.<enum> - YES Type of cost to apply as the virtual cost, i.e., travel time from zone-to-physical-network
"” Smoothing.<enum> - YES Type of smoothing to apply between iterations

Return type

None

Supported types

Traditional static assignment currently supports the following PhysicalCost types:

  • PhysicalCost.BPR

Traditional static assignment currently supports the following Virtual cost types:

  • VirtualCost.FIXED
  • VirtualCost.SPEED

Traditional static assignment currently supports the following Smoothing types:

  • Smoothing.MSA

Example 1

from planit import *

# Choose to run PLANit with a traditional static traffic assignment method
planit_instance = PLANit()
planit_instance.set(TrafficAssignment.TRADITIONAL_STATIC)

# set physical cost to BPR link performance function
planit_instance.assignment.set(PhysicalCost.BPR)

# configure the instantiated property
planit_instance.assignment.physical_cost.<call method>

Example 2

from planit import *

# Choose to run PLANit with a traditional static traffic assignment method
planit_instance = PLANit()
planit_instance.set(TrafficAssignment.TRADITIONAL_STATIC )

# set virtual cost to a constant value for all connectors (zone-to-physical network connections)
planit_instance.assignment.set(VirtualCost.FIXED)

# configure the instantiated property
planit_instance.assignment.virtual_cost.<call method>

Example 3

from planit import *

# Choose to run PLANit with a traditional static traffic assignment method
planit_instance = PLANit()
planit_instance.set(TrafficAssignment.TRADITIONAL_STATIC )

# set virtual cost to a constant value for all connectors (zone-to-physical network connections)
planit_instance.assignment.set(Smoothing.MSA)

# configure the instantiated property
planit_instance.assignment.smoothing.<call method>

See also

Physical Cost for physical cost implementations
Smoothing for smoothing implementations
Virtual Cost for virtual cost implementations

Source code

Class AssignmentWrapper in Wrappers.py

Last modified June 4, 2020: - added methods for BPR function now available in python (setting of parameters) - updated all examples with the correct import statement (8d34232)