Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Wavelet-analysis of series of observations of relative sunspot numbers.
  The dependence of the periods of cyclic activity on the time at different
  time scales   We applied the method of continuous wavelet-transform to high-quality
time-frequency analysis to the sets of observations of relative sunspot
numbers. Wavelet analysis of these data reveals the following pattern: at the
same time there are several activity cycles whose periods vary widely from the
quasi biennial up to the centennial period. These relatively low-frequency
periodic variations of the solar activity gradually change the values of
periods of different cycles in time. This phenomenon can be observed in every
cycle of activity.

9
The categories of this paper are: nlin
34
The categories of this paper are: chem-ph
13
The categories of this paper are: quant-ph
3
The categories of this paper are: physics
4
The categories of this paper are: cond-mat
8
The categories of this paper are: hep-ex
31
The categories of this paper are: ao-sci
19
The categories of this paper are: eess
16
The categories of this paper are: stat
37
The categories of this paper are: supr-con
28
The categories of this paper are: alg-geom
14
The categories of this paper are: math-ph
0
The categories of this paper are: hep-ph
18
The categories of this paper are: econ
10
The categories of this paper are: q-bio
29
The categories of this paper are: funct-an