Ask HN: Anyone know any good maths libraries for Ruby?

Well, basically, what the title says!

I'm currently experimenting with RubyGame(self improvement and all that), as a Rails coder by trade, and I thought it would be interesting to see if there's any library that anyone knows of that does basic things for you (like combining movement vectors)?

I've got some fairly basic maths knowledge myself(maths/cs graduate), so I've got no problem writing all of that myself, but I'm always up for cheating and including a gem that extrapolates calculations for me :D.

I've done a quick google for solutions, but I'm interested in what people think!