On 13/10/15 06:48, Jan Keitel wrote:
In this particular case the problem can probably be resolved by being
a bit stricter with the check in interior_contains:
Instead of checking
return self.polyhedron()._is_positive( self.eval(Vobj) )
one should have
return self.polyhedron()._is_positive( self.eval(Vobj) )
> and not
self.polyhedron()._is_zero( self.eval(Vobj) )
This will not solve the problem! _is_positive(x) returns (x >= -1e-6)...
which is exactly the same thing as _is_nonneg(x)... You will also get
False positive and True negative, won't you? For example, you can be out
of the polytope but get from _is_positive that you are inside.
I would go for:
- a warning for non exact rings (using the method .is_exact())
- using _is_positive for non exact rings
Though, using intensively _is_positive or _is_nonneg might significantly
slows down the code (it is one more Python function call).
Vincent
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