Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Multilevel sparse grids collocation for linear partial differential
  equations, with tensor product smooth basis functions
24
The categories of this paper are: dg-ga
30
The categories of this paper are: q-alg
20
The categories of this paper are: acc-phys
18
The categories of this paper are: econ
4
The categories of this paper are: cond-mat
33
The categories of this paper are: plasm-ph
32
The categories of this paper are: atom-ph
26
The categories of this paper are: bayes-an
22
The categories of this paper are: chao-dyn
3
The categories of this paper are: physics
12
The categories of this paper are: nucl-th
9
The categories of this paper are: nlin
28
The categories of this paper are: alg-geom
27
The categories of this paper are: comp-gas
34
The categories of this paper are: chem-ph
37
The categories of this paper are: supr-con