Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: On the construction of almost general solutions for PDEs arising in
  nonlinear optics   In this communication we consider the widely used nonlinear Fokas-Lenells
equation, the cubic focussing nonlinear Schr\"{o}dinger equation in
(2+1)-dimensions and the coupled Drinfel'd-Sokolov-Wilson equation and attempt
to construct almost general solutions for the envelope of the wave packet by
means of the travelling wave ansatz. The obtained solutions have been expressed
in terms of Jacobi elliptic sine function from which one can obtain the
solitary wave (particular) solutions by imposing appropriate conditions on the
roots of certain quartic polynomials.

0
The categories of this paper are: hep-ph
32
The categories of this paper are: atom-ph
15
The categories of this paper are: nucl-ex
25
The categories of this paper are: patt-sol
33
The categories of this paper are: plasm-ph
7
The categories of this paper are: hep-th
27
The categories of this paper are: comp-gas
37
The categories of this paper are: supr-con
30
The categories of this paper are: q-alg
9
The categories of this paper are: nlin
16
The categories of this paper are: stat
10
The categories of this paper are: q-bio
19
The categories of this paper are: eess
36
The categories of this paper are: cmp-lg
22
The categories of this paper are: chao-dyn
31
The categories of this paper are: ao-sci