The text editor contains a tab called "Cross Products":
This tab assumes that your cross products conform to the genus/differentia method of designating cross products. If you are using another, unrecommended method (ie creating random cross products by hand ), this panel may behave in unexpected ways.
The genus term is listed at the top. Differentia terms are listed in the "Discriminating Relations" section. Each line of this section represents a relationship to a term. The drop down box contains the relationship type, and the button immediately to the right contains the target (parent) term of this relationship.
To the right of each button that contains a term is a button marked with a blue circle. Clicking this button causes the term to be selected in the ontology editor panel. These buttons are for use while browsing, not editing. Clicking one of these buttons will usually cause a new term to be loaded into the text editor, so you will lose any pending changes to the cross product definition if one of these buttons is clicked.
Remember, this component (like all components within the text editor) affects the current sub-selection . The genus and differentia information you enter will be assigned to the current term. No new terms will be created. (To create a new term that is a cross product of two or more existing terms, create a new term first, and then build your cross product definition).
Drag the new genus term onto the button labeled "<drop a genus term>". The text on the button will change to the name of the new genus term.
To assign NO genus term, click the genus term button. The current genus term will be removed.
It is possible to create a valid cross-product with no genus term in OBO-Edit. It is not recommended.
Drop the new differentia term onto the button labelled "drag new terms here". A popup menu will appear containing a list of all available relationship types in the current ontology. Choose an option from the menu to assign a type to your new relationship.
To entirely remove a differentia term, click the garbage can button next to the term.
The cross product tab is located inside the text editor. Therefore, you must click the "Commit" button to make your changes permanent. Otherwise, they will be lost when you click a new term.
Once changes are committed, OBO-Edit will create the hidden links that record your new cross product. If the reasoner is running, OBO-Edit will try to create inferred is_a links based on your new cross-product definition.