[texhax] pgf, parametric plot and line width (thickness)

[Victor Ivrii]

It looks like pgf does not honor line width for parametric plots

\documentclass{article}
\usepackage{pgf,tikz}

\pagestyle{empty}

\begin{document}


\begin{tikzpicture}[x=0.13\linewidth,y=0.13\linewidth]

\draw plot [parametric,domain=-11:25,smooth,samples=1000, THICKNESS]
function{-0.05*t+cos (t),sin(t)};

\end{tikzpicture}
\end{document}

where I replace THICKNESS by  "ultra thin", ...., "ultra thick" or
"line width=10pt" without any effect.



Is there an easy way to control thickness in parametric plots

PS for ordinary plots everything works fine.
PPS Sure I could use Mathematica etc but my question is about pgf

Thank you in advance

Victor