Valid days are closely linked to the calendar as they can be specified on the basis of the selected calendar. First the kind of calendar is thus chosen when modeling, and then valid days are specified on the basis of the respective calendar (User Manual: Creating a valid day).
Valid day is a freely definable set of days of the calendar used. If a weekly calendar is used, a valid day may comprise the days Monday to Friday, for example (the valid day then is designated Mondays to Fridays).
In PuT the timetable is based on a calendar (Calendar). A valid day can be assigned to each vehicle journey section. Optionally, this can consist of an individual day or an example week, however, a defined period on the calendar can also be used. In each case, the availability of individual vehicle journey sections can be specified by valid days. A valid day is a freely definable set of days of the underlying calendar. For each valid day a separate name can be allocated. Valid days usually represent regularly recurring patterns, such as Monday to Friday, but these could also be individual days (for example 01.01.2009). How to define a valid day depends of the selected calendar:
- No calendar
Exclusively uses the valid day daily. It is not possible to create further valid days. Demand and supply are modeled for an unspecified, recurring day in this case.
- Weekly calendar
Apart from the predefined valid day daily any desired valid days can be created, which are specified by entering one or several valid weekdays (e.g. all weekdays with the valid day name Mon-Fri).
- Annual calendar
Valid days can be defined for any day of the year within the calendar period. The following possibilities are provided:
- fixed time period (e.g. 01.01.2008 to 30.06.2008)
- weekdays (e.g. Mon-Fri)
- hard rule (for example during the summer holidays)
- free selection of calendar days (for example 24.12.2007 and 31.12.2007)
In addition to individual valid days, you can define Operating periods in the annual calendar. These are freely defined time periods, such as summer or winter, which are used orthogonal to valid days. This allows you to significantly reduce the number of valid days, as the validity then does not only depend on the valid day, but on the operating period as well. Valid days and operating periods are allocated separately on the level of vehicle journey sections.
In operational public transport planning, it is common practice to model the timetable in operating days. Groups of day types are defined for which a timetable is valid (e.g. "Mon-Fri" or "Thursday" in the vacation season). These operating days are assigned to the calendar in a second step. The operating day includes all the vehicle journeys and line blocks assigned to it. In contrast to the modeling using valid days, vehicle journeys are imported several times and kept in the model when merged into a weekly or annual calendar. Line blocks for a specific operating day have no information on the transition to the following operating day. Visum contains several features to address the redundancy of vehicle journeys and the missing combinations of line blocks for the valid day-based work in Visum (User Manual: Joining line block versions)..
Valid days play a minor part in PrT. Valid days can be used in the following assignment procedures:
- Dynamic stochastic assignment (Dynamic stochastic assignment)
- Dynamic User Equilibrium (DUE) (Dynamic User Equilibrium (DUE))
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Tip: In these procedures, the transport supply can be time-varying. Time-varying attributes are used (Time-varying attributes). When using a calendar, valid days can be specified for these time-varying attributes, on which they should have an effect. |
