Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Normal Truncated Toeplitz Operators   The characterization of normal truncated Toepltiz operators is first given by
Chalendar and Timotin. We give an elementary proof of their result without
using the algebraic properties of truncated Toeplitz operators.

18
The categories of this paper are: econ
3
The categories of this paper are: physics
4
The categories of this paper are: cond-mat
14
The categories of this paper are: math-ph
29
The categories of this paper are: funct-an
36
The categories of this paper are: cmp-lg
0
The categories of this paper are: hep-ph
13
The categories of this paper are: quant-ph
8
The categories of this paper are: hep-ex
16
The categories of this paper are: stat
7
The categories of this paper are: hep-th
6
The categories of this paper are: astro-ph
25
The categories of this paper are: patt-sol
37
The categories of this paper are: supr-con
9
The categories of this paper are: nlin
26
The categories of this paper are: bayes-an