Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Quadratic differentials, half-plane structures, and harmonic maps to
  graphs
4
The categories of this paper are: cond-mat
30
The categories of this paper are: q-alg
33
The categories of this paper are: plasm-ph
10
The categories of this paper are: q-bio
34
The categories of this paper are: chem-ph
19
The categories of this paper are: eess
31
The categories of this paper are: ao-sci
26
The categories of this paper are: bayes-an
12
The categories of this paper are: nucl-th
16
The categories of this paper are: stat
1
The categories of this paper are: cs
24
The categories of this paper are: dg-ga
23
The categories of this paper are: solv-int
20
The categories of this paper are: acc-phys
5
The categories of this paper are: gr-qc
3
The categories of this paper are: physics