Irregular Repeats provide a quick way of handling situations where there is no simple logical rule that determines when an item is going to repeat. Pimlical handles this by creating duplicates of the original event that are linked to the original event. The original event is referred to as the Parent of the irregular repeat series, and the duplicates are referred to as Children of the irregular repeat series.
To set an irregular repeat, you can pick a repeat or non-repeat item and in the Edit dialog, click on the standard Repeat button. The Irregular Repeat button will either display the legend: Create Irregular Repeats or Edit Irregular Repeats(#) - the latter indicating that this event already has had irregular repeats generated for it (# is the count of total irregular repeats associated with this event). When this button is tapped, if there are no existing irregular repeat instances, Pimlical immediately goes to the Date Picker to allow selection of the repeat instances. If there are some irregular repeat instances, a list appears showing the dates of all the instances.
In the Selection list, you can tap on a date and the Delete button to remove it, or you can tap on the Add button to add new irregular repeat instances, at which point the Date Picker appears to allow selection of the repeat instances.
When the Date Picker appears, simply tap the dates on which you want the irregular repeat instances to appear. The Date Picker dialog will continue to display until you have finished entering all the dates - which you signal by tapping the Done button. At that point the irregular repeat instance list re-appears for you to review before committing to generating all the instances. Any new dates that you have just added will be prefixed with an asterisk(*) in front of the date.
To create the instances, tap on the OK button. Note that the instances are not actually created until you exit the Edit dialog, so if you subsequently cancel out of the Edit dialog, those instances will not be created. The repeat instances are just normal events and can either be deleted directly or in the Edit dialog when the parent event has been selected. And these instances can be freely edited or moved to different dates as they are separate events.
It is perfectly reasonable to have an event that is a regular repeat event as well as being the parent of an irregular series. For example, you might have a regular monthly event, but in one month, have some extra meetings, which you can then add using the irregular repeat function.
In an event selection list, you can long-press the parent or child of an irregular repeat series and select Show All Repeat Instances to quickly find all the instances of the repeat (parent and children).
How are irregular repeats handled?
It is important to understand that irregular repeats are very different from regular repeats. A regular repeat is a single event with a rule that defines when the repeats occur. An irregular repeat is a group of separate events that are associated with each other by virtue of having been created using this function (that's how you can locate all the instances of an irregular repeat series).
The reason it works this way is not due to any limitation in Pimlical, but rather because no other calendar application can handle irregular repeats and so the only way to have the irregular instances appear in that other calendar is by generating them as individual events.
Icons for Irregular parents and children
This icon identifes the parent of an irregular repeat series.
This icon identifies the child of an irregular repeat series