Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: A simple hysteretic constitutive model for unsaturated flow
30
The categories of this paper are: q-alg
11
The categories of this paper are: hep-lat
18
The categories of this paper are: econ
2
The categories of this paper are: math
32
The categories of this paper are: atom-ph
15
The categories of this paper are: nucl-ex
5
The categories of this paper are: gr-qc
24
The categories of this paper are: dg-ga
27
The categories of this paper are: comp-gas
14
The categories of this paper are: math-ph
21
The categories of this paper are: adap-org
22
The categories of this paper are: chao-dyn
36
The categories of this paper are: cmp-lg
19
The categories of this paper are: eess
17
The categories of this paper are: q-fin
10
The categories of this paper are: q-bio