Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: On rotational solutions for elliptically excited pendulum   The author considers the planar rotational motion of the mathematical
pendulum with its pivot oscillating both vertically and horizontally, so the
trajectory of the pivot is an ellipse close to a circle. The analysis is based
on the exact rotational solutions in the case of circular pivot trajectory and
zero gravity. The conditions for existence and stability of such solutions are
derived. Assuming that the amplitudes of excitations are not small while the
pivot trajectory has small ellipticity the approximate solutions are found both
for high and small linear damping. Comparison between approximate and numerical
solutions is made for different values of the damping parameter.

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The categories of this paper are: astro-ph
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The categories of this paper are: adap-org
9
The categories of this paper are: nlin
36
The categories of this paper are: cmp-lg
10
The categories of this paper are: q-bio
22
The categories of this paper are: chao-dyn
0
The categories of this paper are: hep-ph
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The categories of this paper are: hep-lat
29
The categories of this paper are: funct-an
18
The categories of this paper are: econ
31
The categories of this paper are: ao-sci
37
The categories of this paper are: supr-con
30
The categories of this paper are: q-alg
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The categories of this paper are: cond-mat
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The categories of this paper are: nucl-th
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The categories of this paper are: hep-th