Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Distributed Parallel D8 Up-Slope Area Calculation in Digital Elevation
  Models
22
The categories of this paper are: chao-dyn
2
The categories of this paper are: math
27
The categories of this paper are: comp-gas
19
The categories of this paper are: eess
36
The categories of this paper are: cmp-lg
8
The categories of this paper are: hep-ex
31
The categories of this paper are: ao-sci
35
The categories of this paper are: mtrl-th
14
The categories of this paper are: math-ph
13
The categories of this paper are: quant-ph
30
The categories of this paper are: q-alg
17
The categories of this paper are: q-fin
3
The categories of this paper are: physics
12
The categories of this paper are: nucl-th
5
The categories of this paper are: gr-qc
18
The categories of this paper are: econ