fix cardinalities

[jeswr]

Resolves #637

[labra]

Thanks for the pull request. I noticed that 3 tests are failing, and I think they can be solved changing the expected results. Do you want to try to change those tests also? If not, I can also try it, but it would take me some time (at least 2 weeks...).

[jeswr]

I'm not in a rush to have this fixed as it is monkey patched in my use case, and I also know very little Scala and don't have a good dev environment for Scala set up sp it may be better for you to fix it when time allows.