# How to draw this diagram/graph using tikz?

I have this diagram, and I have tried to draw it doing every dot and line, but I was wondering, is there a way to do it with foreach cycles or something like that? thanks.

• What have you tried so far? Anyway you are not a new user anymore – user156344 Apr 20 at 8:37
• @close-voters: The OP hasn't been online for 2 hours, i.e. he doesn't know what is going on yet. Give him some time. – user156344 Apr 20 at 10:44
• @JouleV Questions can also be reopened. In its current state it is unclear. Therefore voting to close. – Henri Menke Apr 20 at 11:38
• @HenriMenke The question is not unclear. OP informs us that he/she have solved the problem, but the code used is not optimal OP then asks if somebody may give him a tip how to solve the same with a loop or similar. OP does not ask you to write the code, just provide a hint, as JouleV has done. – Sveinung Apr 20 at 13:00

This does not provide a full code, but a hint so that you can shorten your code. You can use a pic for every group of dots like that.

\documentclass[tikz]{standalone}
\tikzset{
dotcirc/.style={circle,inner sep=2pt,draw,fill=#1},
pics/tripdots/.style args={#1/#2-#3/#4-#5/#6,name=#7}{
code={
\begin{scope}[local bounding box=#7]
\draw (-1.2,0)--(1.2,0);
\draw (0,0.2)--(0,-.2);
\path (-1,0) node[dotcirc=#1] (#2) {};
\path (0,0)  node[dotcirc=#3] (#4) {};
\path (1,0)  node[dotcirc=#5] (#6) {};
\end{scope}
}
}
}
\begin{document}
\begin{tikzpicture}
\pic at (0,0) {tripdots={red/ra-yellow/ya-green/ga,name=a}};
\draw[<-] (a) -- ++(.5,1) node[above] {\scalebox{0.5}{Traffic lights}};
\draw[<-] (ra) -- ++ (.5,-1) node[below] {\scalebox{0.5}{A colored circle}};
\end{tikzpicture}
\end{document}


• A good answer to the question. :) – Sveinung Apr 20 at 13:01
• Thanks a lot!. And a question, I have hear somethimes that "pic" use, but I don't know how it is, is that a package? I know I am not new at this but there are a lot of things I still don't know about tex. – J.Rodriguez Apr 20 at 17:23
• @J.Rodriguez You just have to read chapter 18 of the PGF manual. pic is very useful - it is a syntax in TikZ, not a package. – user156344 Apr 20 at 17:26