NAMay 9, 2018
Hamiltonian systems: symbolical, numerical and graphical studySetsuo Takato, José A Vallejo
Hamiltonian dynamical systems can be studied from a variety of viewpoints. Our intention in this paper is to show some examples of usage of two Maxima packages for symbolical and numerical analysis (\texttt{pdynamics} and \texttt{poincare}, respectively), along with the set of scripts \KeTCindy\ for obtaining the \LaTeX\ code corresponding to graphical representations of Poincaré sections, including animation movies.
NAMay 12, 2019
Using Oshima splines to produce accurate numerical results and high quality graphical outputSetsuo Takato, José A. Vallejo
We illustrate the use of Oshima splines in producing high-quality \LaTeX\ output in two cases: first, the numerical computation of derivatives and integrals, and second, the display of silhouettes and wireframe surfaces, using the macros package KeTCindy. Both cases are of particular interest for college and university teachers wanting to create handouts to be used by students, or drawing figures for a research paper. When dealing with numerical computations, KeTCindy can make a call to the CAS Maxima to check for accuracy; in the case of surface graphics, it is particularly important to be able to detect intersections of projected curves, and we show how to do it in a seamlessly manner using Oshima splines in KeTCindy. A C compiler can be called in this case to speed up computations.