Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Phase Diagram and Commensurate-Incommensurate Transitions in the Phase
  Field Crystal Model with an External Pinning Potential
21
The categories of this paper are: adap-org
22
The categories of this paper are: chao-dyn
37
The categories of this paper are: supr-con
30
The categories of this paper are: q-alg
12
The categories of this paper are: nucl-th
6
The categories of this paper are: astro-ph
14
The categories of this paper are: math-ph
34
The categories of this paper are: chem-ph
31
The categories of this paper are: ao-sci
19
The categories of this paper are: eess
7
The categories of this paper are: hep-th
15
The categories of this paper are: nucl-ex
1
The categories of this paper are: cs
20
The categories of this paper are: acc-phys
24
The categories of this paper are: dg-ga
23
The categories of this paper are: solv-int