Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Symmetrizers and Continuity of Stable Subspaces for Parabolic-Hyperbolic
  Boundary Value Problems
22
The categories of this paper are: chao-dyn
27
The categories of this paper are: comp-gas
28
The categories of this paper are: alg-geom
23
The categories of this paper are: solv-int
5
The categories of this paper are: gr-qc
33
The categories of this paper are: plasm-ph
4
The categories of this paper are: cond-mat
31
The categories of this paper are: ao-sci
25
The categories of this paper are: patt-sol
6
The categories of this paper are: astro-ph
1
The categories of this paper are: cs
21
The categories of this paper are: adap-org
32
The categories of this paper are: atom-ph
17
The categories of this paper are: q-fin
14
The categories of this paper are: math-ph
13
The categories of this paper are: quant-ph