Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Approximation methods for the calculation of eigenvalues in ODE with
  periodic or anti periodic boundary conditions: Application to nanotubes   We compare three different methods to obtain solutions of Sturm-Liouville
problems: a successive approximation method and two other iterative methods. We
look for solutions with periodic or anti periodic boundary conditions. With
some numerical test over the Mathieu equation, we compare the efficiency of
these three methods. As an application, we make a numerical analysis on a model
for carbon nanotubes.

7
The categories of this paper are: hep-th
9
The categories of this paper are: nlin
18
The categories of this paper are: econ
11
The categories of this paper are: hep-lat
29
The categories of this paper are: funct-an
0
The categories of this paper are: hep-ph
30
The categories of this paper are: q-alg
5
The categories of this paper are: gr-qc
28
The categories of this paper are: alg-geom
35
The categories of this paper are: mtrl-th
15
The categories of this paper are: nucl-ex
4
The categories of this paper are: cond-mat
27
The categories of this paper are: comp-gas
37
The categories of this paper are: supr-con
17
The categories of this paper are: q-fin
20
The categories of this paper are: acc-phys