# Colorful undirected graphs in Tikz to demonstrate equivalence classes?

I would like to learn to create this kind of pictures as below with colored vertices in Tikz. The vertex sizes can be the same. This is a graph demonstration (CC BY-SA 3.0) for equivalence classes originating from here. Can this be done with default Tikz or do I need some package?

How can you create colorful undirected graphs like the below in Tikz?

• Yes it can be done. – user10274 Jun 2 '16 at 13:22

I create below two small examples separated by three dots. You can change the line width similarly to the color with the command line width such as \draw [color=red, line width=0.5mm] (0,0)--(1,1).

MWE

\begin{tikzpicture}
\tikzstyle{every node}=[draw, circle, fill=black, inner sep=0pt,minimum size=3pt]
\draw (0,4) node(6){} -- (2,3) node(5){} -- (2,1) node(4){} -- (0,0) node(3){} -- (-2,1) node(2){} -- (-2,3) node(1){} -- cycle;
\draw[color=red] (1) -- (3);
\end{tikzpicture}
...

\begin{tikzpicture}
\tikzstyle{every node}=[draw, circle, fill=black, inner sep=0pt,minimum size=3pt]
\draw[color=green] (2,0) node(4){H4} -- (7,-5) -- (7,-7) -- (6,-8) -- (4,-8) -- (3,-7) -- (3,-6) node(44){H4};

\draw[color=red] (0,-5) node (3){H3} -- (12,-5) node (33){H3};
\draw[color=yellow] (5,-1) node (1){H1} -- (5,-10) node (11){H1};
\draw[color=orange] (10,0) node (2){H2} -- (2,-9) node (22){H2};

\draw[color=pink] (12,-3) node(5){H5} -- (8,-7) node (5){H5};

\end{tikzpicture}


P.s. I am unsure which packages I am using because using Tikz and loading my default preamble. If you know whether this requires any packages besides tikz, do not hesitate to comment or add the info.

• I am having an inheritance issue to place the two tikz pictures side-by-side, aspiring thoughts welcome in chat :) – hhh Jun 2 '16 at 13:52
• Honestly, how long does it take you to make a new file, add \documentclass{article}\usepackage{tikz}\begin{document}<your code>\end{document} and try? (No other packages are required.) – Torbjørn T. Jul 2 '16 at 15:55
• Regarding the problem you mention in chat, do you show the code for the problem anywhere? – Torbjørn T. Jul 2 '16 at 15:59