Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: UNLocBoX: A MATLAB convex optimization toolbox for proximal-splitting
  methods   Convex optimization is an essential tool for machine learning, as many of its
problems can be formulated as minimization problems of specific objective
functions. While there is a large variety of algorithms available to solve
convex problems, we can argue that it becomes more and more important to focus
on efficient, scalable methods that can deal with big data. When the objective
function can be written as a sum of "simple" terms, proximal splitting methods
are a good choice. UNLocBoX is a MATLAB library that implements many of these
methods, designed to solve convex optimization problems of the form $\min_{x
\in \mathbb{R}^N} \sum_{n=1}^K f_n(x).$ It contains the most recent solvers
such as FISTA, Douglas-Rachford, SDMM as well a primal dual techniques such as
Chambolle-Pock and forward-backward-forward. It also includes an extensive list
of common proximal operators that can be combined, allowing for a quick
implementation of a large variety of convex problems.

17
The categories of this paper are: q-fin
5
The categories of this paper are: gr-qc
37
The categories of this paper are: supr-con
8
The categories of this paper are: hep-ex
19
The categories of this paper are: eess
27
The categories of this paper are: comp-gas
14
The categories of this paper are: math-ph
9
The categories of this paper are: nlin
15
The categories of this paper are: nucl-ex
36
The categories of this paper are: cmp-lg
10
The categories of this paper are: q-bio
35
The categories of this paper are: mtrl-th
31
The categories of this paper are: ao-sci
2
The categories of this paper are: math
32
The categories of this paper are: atom-ph
18
The categories of this paper are: econ