Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Superiorization of Preconditioned Conjugate Gradient Algorithms for
  Tomographic Image Reconstruction
36
The categories of this paper are: cmp-lg
32
The categories of this paper are: atom-ph
27
The categories of this paper are: comp-gas
3
The categories of this paper are: physics
23
The categories of this paper are: solv-int
11
The categories of this paper are: hep-lat
35
The categories of this paper are: mtrl-th
25
The categories of this paper are: patt-sol
31
The categories of this paper are: ao-sci
37
The categories of this paper are: supr-con
8
The categories of this paper are: hep-ex
13
The categories of this paper are: quant-ph
19
The categories of this paper are: eess
28
The categories of this paper are: alg-geom
15
The categories of this paper are: nucl-ex
14
The categories of this paper are: math-ph