OK, this is the deal: you need to show you minimal working example showing what you have done some efforts. Not talking but action. For example, a sample, in my view, looks \documentclass[options]{article} \usepackage{tikz} % Obviously you need this \newcommand*{\command}[# of variables]{ % same as latex macro \begin{tikzpicture} \pgfmathsetmacro{\cmd}{macro content}% this is how to define a macro in tikz .... more \node [circle,draw,scale=xx] (A) at (x,y) {A}; % this is how you draw a circle \draw (x,y) circle (2cm}; % can be rectangle too. \draw [options] (x1,y1) to (x2,y2); % this how you draw. .... more \end{tikzpicture} } \begin{document} Here is your codes to achieve your objective, at least partially done/ compilable and then tell us where you problem is. A citation of current known result is preferred. \end{document} Then your question should be clear. Hope that someone has such experience and can answer your concerns. PS: PGF/TikZ (google search this) manual in part VI has a chapter on random number. You may want to read it.