Occurrence is a solid text block associated to the topic. For historical reasons Wandora calls occurrences also as Text datas. Occurrence has a type and a scope. Type is a topic that describes the occurrence, date of birth for example. Scope is also a topic describing the occurrence. Usually scope specifies the language of the occurrence. Occurrence is added to a topic by selecting Add occurrence... menu option. Option opens a dialog window:
Occurrence creation dialog has a button for occurrence type topic and text fields for all languages in Wandora schema. To create an occurrence, user has to select type topic and write text in one or more text fields, and finally click OK button.
Occurrence editor doesn't allow user to specify occurrence languages freely. This is usually enough as languages should not vary too much. To add occurrence of non-listed language, add your language topic as an instance to Wandora language. Read more here.
Topic map standard supports also URL occurrences addition to text occurrences. However, Wandora does not support URL occurrences as it is possible to set URL's external representation, the string representing URL, as the occurrence.
After occurrence creation Wandora user can edit occurrences. To edit single occurrence, user has to click the text field showing occurrence's first words and Wandora opens up an occurrence editor. Occurrence editor is shown below. Editor contains some additional features compared to creation dialog. For example, user can strip html elements in occurrence text with a menu option Edit > Strip HTML tags. Refine menu contains occurrence text classifiers and topic finders for example.
More advanced occurrence operations are found in Topics > occurrence menu of topic tables. These operations include:
- Delete occurrences with type removes occurrences of given type from context topics.
- Delete all occurrences removes all occurrences from context topics.
- Regex replace modifies occurrence text with given regular expression. This can be used to perform rather complicated search and replace operations for example.
See also page Refining occurrences for some advanced occurrence editing options.