% oscillator.tex — undamped mass-spring oscillator.
%
% A harmonic oscillator: m x'' + k x = 0.  Two stocks (position X
% and velocity V) coupled through the spring force F = -k X.

\documentclass{article}
\usepackage[syntax=english]{numodel}

\begin{document}

\numodelsetup{diagram-style=tight}
\newmodelprefix{osc}

\mvar{T}{t}{0}{\s}{2}{systeem}
\mvar{Dt}{dt}{0.01}{\s}{2}{systeem}
\mvar{V}{v}{0}{\m\per\s}{3}{hulp}
\mvar{X}{x}{0.10}{\m}{3}{voorraad}
\mvar{M}{m}{0.250}{\kg}{3}{constante}
\mvar{K}{k}{40}{\N\per\m}{2}{constante}

\mrule{V}{\oscV - (\oscK / \oscM) * \oscX * \oscDt}
\mrule{X}{\oscX + \oscV * \oscDt}
\mrule{T}{\oscT + \oscDt}
\mstop{\oscT >= 1.5}

\section*{Tekstmodel}
\textmodel

\section*{Grafisch model}
\graphicmodel
\directlua{
local f = io.open("oscillator.layout.txt","w")
f:write(numodel.dump_layout("osc")); f:close()
}

\section*{Simulatie}
\computemodel

\section*{Uitwijking}
\diagrammodel{T}{X}{osc-x-t}

\end{document}