# Naming a Graph (Graph Theory)

\begin{tikzpicture}
[acteur/.style={circle, fill=black,thick, inner sep=4pt, minimum size=0.2cm}]
\node (A) at (5,12) [acteur][label=right:0]{};
\node (B) at (8,11) [acteur][label=right:1]{};
\node (C) at (9,9) [acteur][label=left:2]{};
\node (D) at (8,7) [acteur][label=right:3]{};
\node (E) at (5,6) [acteur][label=below:4]{};
\node (F) at (2,7) [acteur][label=right:5]{};
\node (G) at (1,9) [acteur][label=left:6]{};
\node (H) at (2,11) [acteur][label=right:7]{};
\path (A) edge [loop above, thick] node {} (0);
\path (B) edge [loop above, thick] node {} (1);
\path (C) edge [loop above, thick] node {} (2);
\path (D) edge [loop above, thick] node {} (3);
\path (E) edge [loop above, thick] node {} (4);
\path (F) edge [loop above, thick] node {} (5);
\path (G) edge [loop above, thick] node {} (6);
\path (H) edge [loop above, thick] node {} (7);
\end{tikzpicture}


It occur an error when I change

label 0 to label (0,0,0), label 1 to label<br/> (0,0,1) ... and so on


like this

\node (A) at (5,12) [acteur][label=right:(0,0,0)]{};
\node (B) at (8,11) [acteur][label=right:(0,0,1)]{};
... and so on

• Are the <br/> in the code or an effect from a copy paste? Commented Sep 12, 2018 at 16:52
• Welcome to TeX.SX! Please help us (and also you) and add a minimal working example (MWE), that illustrates your problem. Reproducing the problem and finding out what the issue is will be much easier when we see compilable code, starting with \documentclass and ending with \end{document}. - Why (0,0,0)...? Commented Sep 12, 2018 at 16:57
• I guess you only need to put braces around the coordinates (or whatever the 3-tupels are) \node (A) at (5,12) [acteur][label=right:{(0,0,0)}]{};.
– user121799
Commented Sep 12, 2018 at 17:07
• You are right need only to put braces thanks Commented Sep 14, 2018 at 2:35
• @Marvin is your question solved? If yes please accept the given answer. Commented Sep 20, 2018 at 20:29

Welcome to TeX.SE! If you place some sensitive character like (, it might be misinterpreted by the parser. In almost all situations putting things in groups, i.e. putting { and } around them, fixes the issue. And you can make your code much shorter using \foreach. (In principle, one \foreach loop is sufficient, but for the sake of the argument I am using two here.)
\documentclass[tikz,border=3.14mm]{standalone}