You can calculate service trip patterns while the procedure sequence is carried out (Algorithm for service trip pattern calculation).
A service trip pattern has to satisfy the following criteria:
- A service trip pattern can only be created based on a time profile (except for in the schematic line diagram).
- A service trip pattern consists of at least four vehicle journeys.
- The (possibly virtual) departures of vehicle journeys from the start stop point of the time profile have a recurring pattern that is less than four hours.
Any other vehicle journey attributes are not relevant. Particularly, the following attributes are not considered when forming patterns:
- Vehicle journey sections of the vehicle journeys, i.e. the number of sections, their valid days, their vehicle combinations etc.
- Operators
At no point the consistency of the attribute will be checked, i.e. the vehicle journeys of different time profiles may have the same service trip pattern number. Later in the tabular timetable view, only vehicle journeys within one time profile will be grouped to patterns.
1. On the toolbar, click the 
Open 'Procedure sequence' window button.
The Procedure sequence window opens.
2. Add the Calculate service trip patterns procedure of the PuT Analyses category to the position of your choice in the procedure sequence (Setting up and starting the procedure sequence).
3. Make sure that the inserted operation is marked and click the Edit button in the Operations section.
The Parameters: Calculate service trip patterns window opens.
4. Make the desired changes.
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Element |
Description |
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Calculate for active time profiles only |
If this option has been checked, only active time profiles are regarded for service trip pattern calculation. |
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Calculate for active vehicle journeys only |
If this option has been checked, only active vehicle journeys are regarded for service trip pattern calculation. |
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Take the spatial extent of vehicle journeys into account |
If the option has been selected, only vehicle journeys with identical start and end stops are put together in one regular service pattern. |
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Objective of procedure |
Maximize number of vehicle journeys in headway pattern If the option has been selected, the regular services with the maximum number of vehicle journeys are displayed as headway patterns. Notes Besides constant temporal distances of vehicle journeys changing headway patterns are also permitted. Each time difference may occur multiple times (for example, the headway pattern 6/7/7). Maximize temporal dimensions of headway patterns If this option has been selected, the regular services which span the longest period of time are displayed as headway patterns. |
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Base headway |
Identifying service trip patterns with any service interval Select this option to group vehicle journeys with the same differences into service trip patterns. The time differences may differ between trip patterns. Note This option is available if the option Set coordinates of existing centroids is selected. Only fractured multiples of the base headway are permitted as service intervals for a service trip pattern Select this option to specify a base headway that limits the service trip patterns possible. The time difference between vehicle journeys of a service trip pattern must be a multiple of the base headway or a multiple of half, a third, or a quarter of the base headway. Example If you enter a base headway of 30 min, the following service trip patterns are possible:
Notes This option is available if the option Set coordinates of existing centroids is selected. |
5. Confirm with OK.
6. Execute the procedure (Executing procedures in the procedure sequence).
The service trip patterns are computed. The results are saved to the vehicle journey attribute Service trip pattern number.
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Note: You can view the results in a list or in the tabular timetable (Editing regular services). Subsequent processing and modification of service trip patterns is also possible (Editing regular services). |
Algorithm for service trip pattern calculation
The algorithm considers the active vehicle journeys of each time profile separately since vehicle journeys of different time profiles cannot be combined.
At the start the ServTripPatNo attribute of all vehicle journeys is reset to 0. Then the ServTripPatNo 1, 2, ... will be allocated successively to identified service trip patterns until all time profiles have been processed.
The algorithm includes the following steps:
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Note: If in the window Parameters: Calculate service trip patterns, you select Number of veh. journ., the algorithm is performed differently. The following section describes the difference. |
1. For all N vehicle journeys of a time profile the (possibly virtual) departures at the start of the time profile are determined.
2. The vehicle journeys are sorted according to this departure time.
3. The (maximum) m = N • (N - 1) / 2 differences occurring between these departure times are determined. Generally m is much lower because the vehicle journeys already run in regular intervals. The set of M, resulting from the various differences, is sorted in ascending order.
4. For each difference d in M it is checked which maximum service trip pattern G(d) can be formed from the available vehicle journeys with headway d. Maximum here means: covering the longest period, i.e. featuring the longest interval between first and last vehicle journey included.
5. After determination - for each difference d - of the maximum service trip pattern G(d), the pattern g is selected from all patterns which covers the longest interval. In case, several groups cover the same period of time, the group with the greatest number of vehicle journeys is selected.
The second item has the effect that, for example, for perfectly regular vehicle journeys in 1h intervals between 6 am and 10 pm not a 4-hour rhythm with 5 services but a 1-hour rhythm with 17 vehicle journeys will be found.
Should more than one headway be found covering the same (longest) period (1st) and same number of vehicle journeys (2nd) within a time profile, first of all the pattern with the earliest vehicle journey will be formed.
6. The vehicle journeys of the selected group receive the next free number as service trip pattern number. The vehicle journeys are then removed from the set of all vehicle journeys considered.
7. This algorithm is applied repeatedly to the remaining vehicle journeys of a time profile until no further service trip pattern can be formed.
If in the window Parameters: Calculate service trip patterns, you select Number of veh. journ., the algorithm is performed differently.
1. For all N vehicle journeys of a time profile the (possibly virtual) departures at the start of the time profile are determined.
2. The vehicle journeys are sorted according to this departure time.
3. The (maximum) m = N • (N - 1) / 2 differences occurring between these departure times are determined. Generally m is much lower because the vehicle journeys already run in regular intervals. The set of M, resulting from the various differences, is sorted in ascending order.
4. For each difference d, starting with the smallest, it is checked whether there are groups with an overlapping time period, so that the differences of the first departures are added to the difference d. These are the combinations that are looked for.
5. From such possible group combinations, the one combination is chosen that represents the combined group with the most trips. These groups are combined.
6. With the combination, redundant trips are again grouped into service trip patterns.
7. These steps are repeated until no more groups can be combined.
8. The vehicle journeys of the selected group receive the next free number as service trip pattern number. The vehicle journeys are then removed from the set of all vehicle journeys considered.
9. This algorithm is applied repeatedly to the remaining vehicle journeys of a time profile until no further service trip pattern can be formed.
