I don't think that there is a problem.. For example test suite problem 1: h1 = abs(randn); h2 = sqrt(3)*h1; is a cube of random size. By adding + abs(randn), I violate the constraint h2 <= sqrt(3)*h1. If I put parentheses around h1+abs(randn), I have the same effect as before, just with another scaling of the random number that I added.. --> Result is the same: violation of the constraint for the cube. Same with test suit problem 2

Oh, sorry. I see now that these are the cases that are supposed to check that our code returns the correct responses when the inputs are "out of bounds". Thanks for pointing that out!

Tip: the 8 tetrahedra at the cube corners are not regular, but they have equilateral triangles as base.

PS: Kudos for the author, nice figures. It's so rare to find a problem with graphics at Cody. And sometimes a picture conveys much more than a long text.