Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Numerical analysis of the existence and stability of nonlinear
  excitations in a parametric model of ferromagnetic chain
20
The categories of this paper are: acc-phys
28
The categories of this paper are: alg-geom
37
The categories of this paper are: supr-con
8
The categories of this paper are: hep-ex
21
The categories of this paper are: adap-org
5
The categories of this paper are: gr-qc
12
The categories of this paper are: nucl-th
22
The categories of this paper are: chao-dyn
4
The categories of this paper are: cond-mat
32
The categories of this paper are: atom-ph
29
The categories of this paper are: funct-an
24
The categories of this paper are: dg-ga
35
The categories of this paper are: mtrl-th
33
The categories of this paper are: plasm-ph
10
The categories of this paper are: q-bio
6
The categories of this paper are: astro-ph