Checking the network

You can check the consistency of your network model with this functionality.

Note: The sections PrT and PuT are only available if you have activated the respective add-on (Enabling or disabling add-ons).

1.  On the Calculate menu, click Network check.

The Check network window opens. The entries are grouped (General, PrT, PuT).

2.  Select what you want to check the network for.

Section General

Element

Description

Isolated nodes

The option checks the network for nodes which are not connected to any link.

Note

These are irrelevant to the model and can be deleted.

Turns and main turns that do not make sense

The option checks whether the network contains turns or main turns which are open to a transport system which is yet closed to the From link or To link.

You can select the transport systems for the check in a separate window by clicking on the transport systems displayed.

Note

Only PrT and PuT transport systems can be selected, yet no PuT Walk transport systems.

Invalid matrix values

This option checks whether the network contains invalid values in matrices. These values can occur during the calculation in demand procedures and cause the calculation to abort in the following iteration of the procedure. Invalid values are:

  • NaN (not a number)
  • Inf (infinite)
  • Subnormal values (floating point numbers whose absolute value is so small that they no longer have a normalized representation)

Using the Edit link in the Parameters column, you can set all invalid values to 0. For Inf you can define a substitute value in the range +/- 9999999. Subnormal values are always replaced by 0.

Note

The check for invalid matrix values is always carried out automatically, independent of this function, when calculating demand procedures. You can avoid this automatic check by using a user-defined attribute with the ID 'DisableNaNChecks' and the truth value 'true'.

Section PrT

Element

Description

Zones without PrT connection

The option checks if the network contains zones without a PuT connection. It checks for the existence of connectors and whether they are open to PrT transport systems. For zones with demand distribution as percentages, the connector shares are also checked.

Check network consistency

The option checks for consistent paths between object pairs for the selected transport system selection.

Use the Edit link in the Parameters column to specify for which object pairs you want to run the check and which objects shall be origins and destinations:

Checked OD pairs

Use the drop-down list to specify the set of OD pairs to be checked.

  • All pairs of zones
  • Pairs of active zones
  • Active OD pairs
  • OD pairs with demand

If the option has been selected, the program checks the following:

  • Is there a demand segment which uses the transport system to be checked (via the mode) and to which exactly one matrix has been allocated via the matrix reference?
  • Does the OD pair in this allocated matrix have a value > 0?

Origins and destinations

Use the drop-down list to specify which objects are origins and destinations:

  • Zones: pairs of zones
  • Relevant connector nodes: pairs of nodes connected to different zones. The connectors are open to the transport system to be checked.
  • Zones or relevant connector nodes with weight > 0: Pairs of zones with no connector weights or with connector weights for the entire OD demand, or pairs of nodes that are connected to a zone with connector weights for each single relation. The connectors are open to the transport system to be checked.
  • Active nodes: Pairs of active nodes. You can use this selection, for example, to check the network consistency between pickup points and dropoff points in tour planning.

You can select the transport systems for the check in a separate window by clicking on the transport systems displayed.

Dead-end roads PrT

The option checks whether the network contains dead-end roads with no connection to the network and no U-turn or opposite direction.

You can select the transport systems for the check in a separate window by clicking on the transport systems displayed.

Links without succeed. link

The option checks whether the network contains links with no connection to the network, which are closed to the selected transport systems.

Notes

These are links which yet have a succeeding link but at the To node, the turns or the succeeding links are closed to the transport system. These links should be checked and edited.

You can select the transport systems for the check in a separate window by clicking on the transport systems displayed.

Links with Capacity PrT = 0 or v0 = 0

The option checks the network for PrT links with a capacity PrT = 0, or a speed v0 = 0.

Note

Such links are like closed links, so that no traffic can traverse them during assignments.

Multiple straight turns and main turns

The option checks the network for nodes which with more than one straight (main) turn per incoming link.

Note

This option does not work if you have selected the According to the angle of the turn option under Network > Network settings > Network objects.

Viability for ICA

The option checks the network for nodes or main nodes of the type two-way stop, signalized, or all-way stop, which have not been modeled correctly for an ICA calculation. The program also checks whether the green time of a signal group is zero and if files exist for all external signal controls. In addition, it is checked whether there are PrT connectors at ICA nodes or ICA main nodes.

Notes

Partial nodes of main nodes are not checked. Only those nodes and main nodes are checked, for which ICA has been selected as impedance calculation method.

Viability for ANM export

The option checks the network for lane turns with closed incoming lanes or incoming lanes with transport systems with no possible turns. In addition, it lists (main) nodes with an open connection for one of the predefined transport systems and (main) nodes whose control type is not unknown.

Notes

This check is only performed for (main) nodes whose attribute Use lane definition is true.

You can select the transport systems for the check in a separate window by clicking on the transport systems displayed.

Viability for Balance / Epics

The option checks whether the network is viable for the PTV Epics/Balance module. Among others, the following checks are run:

  • Links:
  • which are not located entirely within a main node
  • Finding incoming and outgoing pocket lanes, which in total are longer than the link itself, between two through lanes (or before the first or after the last).
  • Turns:
  • which do not belong to a main node/main turn
  • Finding lanes with different numbers of signal groups on a turn
  • Detectors with the following attribute values
  • Length = 0
  • SCNo = 0
  • ChannelNo = 0
  • ChannelNo > 255
  • Num Lanes = 0 and Num Crosswalks = 0

Detectors with allocations to (main) nodes and count locations

  • If the detector is allocated to a node, the link that is indirectly allocated via the count location must be an incoming or outgoing link of this node.
  • If the detector is allocated to a main node, the link that is indirectly allocated via the count location must be a cordon link or an inner link of this main node.
Auto link orientation

The option finds links whose From-(main)node-orientation or To-(main)node-orientation does not match the one that would be set by a recalculation.

If faulty links are found, you can repair them directly.

Section PuT

Element

Description

Zones without PuT connection

The option checks the network for zones without a PuT connectors. It checks for the existence of connectors and whether they are open to PuT transport systems.

Note

For zones with demand distribution as percentages, the connector shares are also checked.

Links with PuT-Walk time = 0

The option checks the network for PuT Walk links with a time = 0.

Links with PuT-Aux time = 0

The option checks the network for PuT Aux links with a time = 0.

Links with PuT run time = 0

The option checks the network for links with a PuT run time = 0, i.e. links, which are traversed by a line route of a specific transport system which has a link run time of 0s for the transport system and, in addition, a length or link type speed = 0 for the transport system.

Find line and system routes with zigzags

This option checks whether the network contains (trivial) zigzag courses on line routes and system routes. If zigzags are found, you can repair them in the Messages window if the served stops can be kept in their order.

Alternatively, you can remove zigzags in the network editor (Removing zigzags from a route course)

Furthermore, the function finds (trivial) loops in route courses. A loop occurs when the same route point is passed multiple times. Within the loop, the same route points are traversed for outward and return directions. Trivial loops have no other profile points within the loop. After the check, you can repair loops in the message window.

You can select the transport systems for the check in a separate window by clicking on the transport systems displayed.

Vehicle combinations without vehicle unit

The option checks the network for vehicle combinations without vehicle units.

Inconsistent couplings

The option checks the network for couplings that are not consistent. Those are couplings with valid days which do not overlap. If a vehicle journey operates, for example, Monday to Friday and the coupled vehicle journey operates at the weekend only, the coupling has no effect.

Stop areas with the same node

The option checks the network for stop areas of the same stop which have the same access node and thus permit direct transfers in zero time.

PuT connector nodes without stop area

The option checks the network for PuT connectors which lead to nodes without a stop area.

Note

We recommend this check if you have selected the Force boarding/alighting at connected node option under Calculate > General procedure settings > entry PuT settings > entry Assignment for the Walk links from/to connectors option.

PuT connector nodes without lines

The option checks the network for PuT connectors which lead to nodes with stop areas which are not served by any lines as alighting or boarding is not permitted at any of the stop points.

Notes

If the connector node has no stop area or no line serves the node, passengers use walk links before / after using the connector.

We recommend this check if you have selected the Force boarding/alighting at connected node option under Calculate > General procedure settings > entry PuT settings > entry Assignment for the Walk links from/to connectors option.

Access and egress at inaccessible stop points

The option checks if the network contains stop points that do not have a PuT Walk connection to zones, but where at least one vehicle journey stops (access or egress). For each of these stops, the check issues the concerned vehicle journeys.

Use the Edit link in the Parameters column to set for which Mode the check should be run. In addition, you can restrict the check to the active vehicle journeys using the Use only active vehicle journey sections as filter for... option.

Note

Using the repair function in the Messages window, you can prohibit boarding and alighting for the respective vehicle journeys at such stops.

Invalid chained up vehicle journey sections

The option checks whether the network contains invalid chained up vehicle journey sections of which origin or destination vehicle journey section do not run on the planned calendar day or the destination vehicle journey section is used repeatedly on the same calendar day.

Checks for passenger trip chains with an origin vehicle journey section that does not end at the same stop where the destination vehicle journey sections begins.

Forced chainings with an invalid vehicle combination are displayed.

Lines without a fare system

The option checks whether the network contains lines that do not belong to a fare system.

Parallel vehicle journeys of a time profile

The option checks whether the network contains vehicle journeys that simultaneously use the same time profile during the analysis period.

Vehicle journey items without vehicle journey sections

This option checks whether the network contains vehicle journey items that are not covered by a vehicle journey section. A missing coverage may occur if you delete or shorten vehicle journey sections.

Note: Use the and buttons to select all check options simultaneously or to reset the selection. Use the symbol to reverse the selection. You can also activate several options by selecting them in the window and activating/deactivating them using the shortcut menu or the space bar on the keyboard.

You can collapse the General, PrT and PuT sections by double-clicking the section names.

3.  Click the Run selected network checks button.

The check is executed. The result of each option is displayed in the Details column and in the corresponding tooltip. The link in the Messages column takes you to the window of the same name, which contains further information (Messages window). You can correct errors directly.

Note: You can correct errors while the Check network window is open, for example via the Messages window. You can then repeat the check in the open Check network window.