Cross Products By Hand

OBO-Edit treats intersections as special cases of regular relationships. When OBO-Edit sees the following line in an OBO file:

intersection_of: functions_in go_ext:hair

OBO-Edit creates a special relationship to go_ext:hair with the type functions_in. This special relationship acts like a normal relationship in most ways, but it is flagged in the datamodels (and in the display) to indicate that this relationship is involved in an intersection.

These special relationships are normally hidden, because there is no reason to see them if you are editing cross products in the text editor .

However, since intersection relationships are just like any other relationship to OBO-Edit, you can view and edit intersection relationships in the ontology editor panelTHIS IS NOT A GOOD IDEA. The only reason you would need this functionality is if you intend to violate the genus/differentia paradigm. Therefore, this feature is hidden by default.

But you can turn it on. Don't say we didn't warn you.

Displaying Intersections in the ontology editor panel

  1. Go to the "Plugins" menu and choose the "Global Filter Plugin".
  2. Click the "Filters" tab. You should see this:
    .
    By default, OBO-Edit contains an item that filters out all intersection links in the main view. The filter will appear in the "Link filters" section, and will be labeled "Link has NOT Is complete".
  3. Click the link filter to select it. The screen will change to look like this:
  4. Click the "Del" button underneath the link filter. The Link filter will disappear.
  5. Click the "Save Changes" button to make this change permanent.

Intersection links will now appear in the main viewer. They are marked with a red triangle: