Dear all,
When computing the regions of a hyperplane arrangements, it fails and raises the following:
ValueError: *Input Error: Input format is not correct.
*Format:
begin
m n NumberType(real, rational or integer)
b -A
end
Yet when running the command vertices, it computes it which is confusing!
The full code is:
P = [[-0.48, 0.83], [-5.33, 9.23]]
Q = [[0.43, 0. ], [9.04, 0. ]]
Z = [[-0.35, -0.60], [-1.44, -2.49]]
V = VoronoiDiagram(P)
R = [r for r in V.regions().items()]
s = R[0][1].hyperplane_arrangement()
V = VoronoiDiagram(Q)
R = [r for r in V.regions().items()]
s = s.add_hyperplane(R[0][1].hyperplane_arrangement())
V = VoronoiDiagram(Z)
R = [r for r in V.regions().items()]
s = s.add_hyperplane(R[0][1].hyperplane_arrangement())
s.regions()
How can I overcome this eerie bug?
This means that there is an intersection but the sage cant attain the regions which is weird as stated before!
P.s. The full traceback:
---------------------------------------------------------------------------
ValueError Traceback (most recent call last)
<ipython-input-6-4ba993d8025f> in <module>()
----> 1 s.regions()
/opt/sagemath-9.0/local/lib/python3.7/site-packages/sage/misc/cachefunc.pyx in sage.misc.cachefunc.CachedMethodCallerNoArgs.__call__ (build/cythonized/sage/misc/cachefunc.c:12712)()
2308 if self.cache is None:
2309 f = self.f
-> 2310 self.cache = f(self._instance)
2311 return self.cache
2312
/opt/sagemath-9.0/local/lib/python3.7/site-packages/sage/geometry/hyperplane_arrangement/arrangement.py in regions(self)
1608 R = self.base_ring()
1609 dim = self.dimension()
-> 1610 universe = Polyhedron(eqns=[[0] + [0] * dim], base_ring=R)
1611 regions = [universe]
1612 for hyperplane in self:
/opt/sagemath-9.0/local/lib/python3.7/site-packages/sage/geometry/polyhedron/constructor.py in Polyhedron(vertices, rays, lines, ieqs, eqns, ambient_dim, base_ring, minimize, verbose, backend)
660 if got_Vrep:
661 Vrep = [vertices, rays, lines]
--> 662 return parent(Vrep, Hrep, convert=convert, verbose=verbose)
/opt/sagemath-9.0/local/lib/python3.7/site-packages/sage/structure/parent.pyx in sage.structure.parent.Parent.__call__ (build/cythonized/sage/structure/parent.c:9245)()
900 return mor._call_(x)
901 else:
--> 902 return mor._call_with_args(x, args, kwds)
903
904 raise TypeError(_LazyString(_lazy_format, ("No conversion defined from %s to %s", R, self), {}))
/opt/sagemath-9.0/local/lib/python3.7/site-packages/sage/structure/coerce_maps.pyx in sage.structure.coerce_maps.DefaultConvertMap_unique._call_with_args (build/cythonized/sage/structure/coerce_maps.c:5081)()
178 print(type(C), C)
179 print(type(C._element_constructor), C._element_constructor)
--> 180 raise
181
182
/opt/sagemath-9.0/local/lib/python3.7/site-packages/sage/structure/coerce_maps.pyx in sage.structure.coerce_maps.DefaultConvertMap_unique._call_with_args (build/cythonized/sage/structure/coerce_maps.c:4969)()
173 return C._element_constructor(x, *args)
174 else:
--> 175 return C._element_constructor(x, *args, **kwds)
176 except Exception:
177 if print_warnings:
/opt/sagemath-9.0/local/lib/python3.7/site-packages/sage/geometry/polyhedron/parent.py in _element_constructor_(self, *args, **kwds)
523 if convert and Vrep:
524 Vrep = [convert_base_ring(_) for _ in Vrep]
--> 525 return self.element_class(self, Vrep, Hrep, **kwds)
526 if nargs == 1 and is_Polyhedron(args[0]):
527 polyhedron = args[0]
/opt/sagemath-9.0/local/lib/python3.7/site-packages/sage/geometry/polyhedron/backend_cdd.py in __init__(self, parent, Vrep, Hrep, **kwds)
459 sage: TestSuite(p).run()
460 """
--> 461 Polyhedron_cdd.__init__(self, parent, Vrep, Hrep, **kwds)
/opt/sagemath-9.0/local/lib/python3.7/site-packages/sage/geometry/polyhedron/base.py in __init__(self, parent, Vrep, Hrep, **kwds)
125 elif Hrep is not None:
126 ieqs, eqns = Hrep
--> 127 self._init_from_Hrepresentation(ieqs, eqns, **kwds)
128 else:
129 self._init_empty_polyhedron()
/opt/sagemath-9.0/local/lib/python3.7/site-packages/sage/geometry/polyhedron/backend_cdd.py in _init_from_Hrepresentation(self, ieqs, eqns, verbose)
114 s = cdd_Hrepresentation(self._cdd_type, ieqs, eqns)
115 s = self._run_cdd(s, '--redcheck', verbose=verbose)
--> 116 s = self._run_cdd(s, '--repall', verbose=verbose)
117 self._init_from_cdd_output(s)
118 if not self.base_ring().is_exact():
/opt/sagemath-9.0/local/lib/python3.7/site-packages/sage/geometry/polyhedron/backend_cdd.py in _run_cdd(self, cdd_input_string, cmdline_arg, verbose)
163 if 'Error:' in ans + err:
164 # cdd reports errors on stdout and misc information on stderr
--> 165 raise ValueError(ans.strip())
166 return ans
167
ValueError: *Input Error: Input format is not correct.
*Format:
begin
m n NumberType(real, rational or integer)
b -A
end
