model.intRule().create(<tag>,<ftag>) creates an integration rule for the frame <ftag>.

 model.intRule(<tag>).frame(<ftag>) sets the frame for the integration rule.

 model.intRule(<tag>).create(<ftag>) creates an integration rule feature.

 model.intRule(<tag>).feature(<ftag>).order(gporder) specifies the integration order of the integration rule.

 model.intRule(<tag>).frame() returns the frame as a string.