This extended abstract introduces the event log generation facility of CPN IDE. CPN IDE has replaced CPN Tools as a tool for editing and simulating (Coloured) Petri Net models. The main advantage of generating event logs with CPN IDE is that it typically will work on existing models by providing some additional information, and that typically the models themselves do not require any change. Basically, the only change that may be required is the consistent use of a single variable for the case identifier.
1. CPN IDE
Although it is possible to create event logs using CPN Tools [
Figure 1 shows a screenshot of CPN IDE where a model has been loaded and has been simulated for 500 steps while recording events and their timestamps. In the main toolbar, at the top, the box preceding the Record events item has been selected, indicating that events are being recorded, and the box preceding the Record event times has been checked, indicating that timestamps are being recorded for the events. To get to such a state from which we can export an event log, the user only needed to check both these items as additional actions to performing the simulation as usual.
If timestamps are recorded, then two events are recorded in the back-end for every transition that (1) was fired and (2) does not have black fill: A start event and a complete event. If a transition has a black fill, no events will be recorded. The timestamp for the start event simply equals the current simulation time when the transition fired, but the timestamp of the complete event is more involved. For this, we compare the token values in the new marking (after the transition has fired) with the token values in the old marking (before the transition fired) and take the lowest time of any token value in the new marking that is not in the old marking. If no such token value exists, the current simulation time is used. As an example, if a transition fires at time and produces tokens at times + 1, + 2, and + 3, then the start event will have timestamp and the complete event will have timestamp + 1.
The recorded events can now be exported to an event log using the Play Out Recorded Events
form in the lower left corner. For this export, the user needs to provide the following
configuration settings:
• Case Id: This should be the name of the variable that is used as the case identifier of an
event. Only recorded events that have this variable as an input in their binding will be
exported.
• Starting Moment: The date and time that coincides with the simulation time 0.0.
• Time Unit: The relation between wall clock time and simulation time. As an example, if set
to “hours”, then a simulation time of 1.0 means one hour.
• Lifecycle Transition Attribute: Which events will be exported to the event log:
• start: Only start events will be exported.
• complete: Only complete events will be exported.
• start+complete: Both start and complete events will be exported.
• in transition name: Only start events will be exported, but the lifecycle
transition start will be replaced by the lifecycle transition as found in the
transition name. As an example, if the transition name equals A+resume, then
start will be replaced by resume, which effectively replaces the start event with
a resume event. If no valid lifecycle transition is found in the transition name,
start will be replaced by the empty string.
• Keep Information on Event Level: Has no use at the moment.
• Log Format: The format for the exported log, either xes (for XES [
After having provided these settings, the user can select the Run button in the form, which will ask the user for the name of the log file. After having provided this name, the log will be exported to a file with that name (with either the extension .xes or .csv added). The exact location of the file will be shown in the Project console.
From https://cpnide.org/ you can download the latest releases for CPN IDE. The latest release is CPN IDE 1.23.0725.
From the Latest downloads section on https://cpnide.org/ you can also download a screencast on how to generate an event log in CPN IDE. In this screencast, we load an example model (which can also be downloaded from the Latest downloads section), start the simulator, select to record events together with their timestamps, and then simulate the model for 500 steps. After this, we select how the events that are recorded in the back by the controller should be exported to an event log, and have the controller export them accordingly.
On https://github.com/cpn-io/cpn-js/ you will find the sources for CPN IDE. CPN IDE is Open Source.
CPN IDE has been extended with functionality that allows the user to generate event logs from (new or existing) CPN models, provided that a single variable is used for the case identifier throughout the model. The user can simply load the model into CPN IDE, select the option to record events (and possibly also event times), simulate the model for some time, and then to export an event log from the events that have been recorded.
The variable for the case identifier plays an important role in this extension, as a recorded event is exported to the event log if and only if the event has this variable as input. This also means that from the same collection of recorded events event logs from different perspectives can be exported. As an example, if a single variable is used throughout the model for a resource, then this variable could be used as well, leading to an event log containing a trace for every different resource.
For future work we are thinking of adding an option to import and/or export models from and
to PNML [