Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Ordinal spectrum: a frequency domain characterization of complex time
  series   Although classical spectral analysis is a natural approach to characterise
linear systems, it cannot describe a chaotic dynamics. Here, we propose the
ordinal spectrum, a method based on a spectral transformation of symbolic
sequences, to characterise the complexity of a time series. In contrasts with
other nonlinear mapping functions (e.g. the state-space reconstruction) the
proposed representation is a natural approach to distinguish, in a frequency
domain, a chaotic behavior. We test the method in different synthetic and
real-world data. Our results suggest that the proposed approach may provide new
insights into the non-linear oscillations observed in different real data.

1
The categories of this paper are: cs
2
The categories of this paper are: math
11
The categories of this paper are: hep-lat
0
The categories of this paper are: hep-ph
23
The categories of this paper are: solv-int
4
The categories of this paper are: cond-mat
12
The categories of this paper are: nucl-th
33
The categories of this paper are: plasm-ph
29
The categories of this paper are: funct-an
17
The categories of this paper are: q-fin
15
The categories of this paper are: nucl-ex
5
The categories of this paper are: gr-qc
37
The categories of this paper are: supr-con
31
The categories of this paper are: ao-sci
34
The categories of this paper are: chem-ph
25
The categories of this paper are: patt-sol