I just tried coping & pasting code from How to draw Venn diagrams (especially: complements) in LaTeX
and I get errors … I suppose I need to install/configure Lyx to use PGF/Tikz?
[Tex/LaTex] Using PGF in Lyx
lyxtikz-pgf
Related Solutions
Here is a little bit advanced but not so difficult to understand grid construction:
\documentclass{article}
\usepackage{tikz}
\begin{document}
\begin{tikzpicture}
\begin{scope}
\clip (0,0) rectangle (10cm,10cm); % Clips the picture...
\pgftransformcm{1}{0.6}{0.7}{1}{\pgfpoint{3cm}{3cm}} % This is actually the transformation
% matrix entries that gives the slanted
% unit vectors. You might check it on
% MATLAB etc. . I got it by guessing.
\draw[style=help lines,dashed] (-14,-14) grid[step=2cm] (14,14); % Draws a grid in the new coordinates.
\filldraw[fill=gray, draw=black] (0,0) rectangle (2,2); % Puts the shaded rectangle
\foreach \x in {-7,-6,...,7}{ % Two indices running over each
\foreach \y in {-7,-6,...,7}{ % node on the grid we have drawn
\node[draw,circle,inner sep=2pt,fill] at (2*\x,2*\y) {}; % Places a dot at those points
}
}
\end{scope}
\end{tikzpicture}
\end{document}
Here is the output:
If you combine it with Peter's code it would be almost ready. Note that there is a scope environment around my code that keeps the transformation local to that scope. Cehck the manual for some intuition about the command \pgftransformcm
You could start Tex Live Utility (a program on your mac and part of MacTeX) and update all packages.
Best Answer
You need to add
\usepackage{pgfplots}to your preamble. In LyX, you can edit the preamble underDocument | Settings | LaTeX Preamble.