CGAL users discussion list

[Eric Berberich <>]

muhibur wrote:
> Hi
> When I try inserting curves into the arrangement, for some curves i get the
> following error - assertion violation, dir_res!=EQUAL. Could anybody
> suggest as to why this error occurs and how to avoid it?
> Thanks,
> Muhib.

Dear Muhib,

first of all, it would be nice if you provide more information, e.g., 
which curves (maybe with data of a "minimal" example), which CGAL 
version, etc...

My guess is that you are inserting conic curves, as this error only 
occurs in exactly one file.
Arr_geometry_traits/Conic_x_monotone_arc_2.h

It seems that you construct a 0-dimensional "arc", which is not allowed. 
The question is, whether the construction is during the arrangement 
computation (in which case there might be a bug in the package), or 
while you are creating your own input curves. But this information is 
also missing ... so, please provide more details which helps us to help you.

eriC