Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A short proof that sweeping is always possible for a spatial
  discretization with regular triangles and no hanging nodes   Sweeping is a commonly used procedure to explicitly solve the discrete
ordinates equation, which itself is a common approximation of the neutron
transport equation. To sweep through the computational domain, an ordering of
the spatial cells is required that obeys the flow of information. We show that
this ordering can always be found, assuming a discretization of the spatial
domain with regular triangles with no hanging nodes.

9
The categories of this paper are: nlin
7
The categories of this paper are: hep-th
24
The categories of this paper are: dg-ga
15
The categories of this paper are: nucl-ex
32
The categories of this paper are: atom-ph
12
The categories of this paper are: nucl-th
6
The categories of this paper are: astro-ph
27
The categories of this paper are: comp-gas
20
The categories of this paper are: acc-phys
16
The categories of this paper are: stat
30
The categories of this paper are: q-alg
0
The categories of this paper are: hep-ph
23
The categories of this paper are: solv-int
4
The categories of this paper are: cond-mat
21
The categories of this paper are: adap-org
3
The categories of this paper are: physics