# Create a footnote in node in a tikzpicture

I would like to add a footnote to a node in a TikZ picture, but every solution I could imagine fails. I tried using a minipage, too.

\documentclass[a4paper,10pt]{scrartcl}
\usepackage{tikz}

\begin{document}
\begin{tikzpicture}
\foreach \x/\y/\number/\year in {
0.5/0.46/ 4.624/2001,
1.5/0.89/ 8.965/2002\footnotemark,
2.5/1.18/11.892/2003
}
{
\draw (\x cm, 0 cm) rectangle (0.5 cm + \x cm, \y cm) node at (0.25 cm + \x cm, \y cm + 0.25 cm) {\tiny\number};
\node[rotate=45, left] at (0.6 cm +\x cm,-0.1cm) {\year};
};
\end{tikzpicture}
\footnotetext{foo}
\end{document}


The output shown is

! Missing number, treated as zero.
}
l.18   }
;


The footnote text is displayed correctly, but the footnote mark is not.

I tried using a minipage as following. I replaced

\node[rotate=45, left] at (0.6 cm +\x cm,-0.1cm) {\year};


with

\node[rotate=45, left] at (0.6 cm +\x cm,-0.1cm) {\begin{minipage}{2em}\year\end{minipage}};


Follow-up question: How to create multiple footnotes with the hyperref package?

\documentclass[a4paper,10pt]{scrartcl}
\usepackage{tikz}

\usepackage[
pdfpagelabels,
pdfstartview=FitH,
plainpages=false,
hypertexnames=false
]{hyperref}

\begin{document}

\begin{tikzpicture}

\foreach \x/\y/\Number/\Year in {
0.5/0.46/ 4.624/2001,
1.5/0.89/ 8.965/2002\footnotemark,
2.5/1.18/11.892/2003\footnotemark
}
{
\draw (\x cm, 0 cm) rectangle (0.5 cm + \x cm, \y cm) node at (0.25 cm + \x cm, \y cm + 0.25 cm) {\tiny\Number};
\node[rotate=45, left] at (0.6 cm +\x cm,-0.1cm) {\Year};

};

\end{tikzpicture}

\footnotetext{foo1}
\footnotetext{foo2}

\end{document}

• Hi nathanori, welcome to the site! Have you seen Minipage footnote is inside tikZ node, which sounds pretty similar to your problem? If not, could you add a bit more information to your question (what exactly have you tried, what do you mean by "fails"?) – Jake Apr 8 '13 at 20:56
• Hi @Jake, thank you for your fast answer! I saw Minipage footnote is inside tikZ node but the footnote there is not used inside the tikzpicture, but outside of it. I added more information to my post and hope that helps. Please try the code sample, it will result in an error. – nathanori Apr 8 '13 at 21:11
• TikZ picture can be placed in certain boxes minipages and footnote can be placed in them or beneath those boxes etc. so forcing a footnote mechanism inside the graphics part is like making coffee with the radiator water. They serve different purposes. – percusse Apr 8 '13 at 21:15
• Hi @percusse, what would you propose to use then? I would like to draw a bar chart and found tutorials proposing tikz. I would appreciate a better solution. – nathanori Apr 8 '13 at 21:18
• I mean a graphics object doesn't have a footer to place the footnote. If you have more details to explain then you might do it in the caption of the figure or use other ways of including data. – percusse Apr 8 '13 at 21:32

It's quite dangerous using \number in that context, because it's an important primitive of TeX that's indeed used for printing the footnote number; that's why TeX gets very confused: it means something completely unexpected when it's necessary to use its original meaning.

Also \year is a primitive; better using another name also for it.

\documentclass[a4paper,10pt]{scrartcl}
\usepackage{tikz}

\begin{document}
\begin{tikzpicture}
\foreach \x/\y/\Number/\Year in {
0.5/0.46/ 4.624/2001,
1.5/0.89/ 8.965/2002\footnotemark,
2.5/1.18/11.892/2003
}
{
\draw (\x cm, 0 cm) rectangle (0.5 cm + \x cm, \y cm)
node at (0.25 cm + \x cm, \y cm + 0.25 cm) {\tiny\Number};
\node[rotate=45, left] at (0.6 cm +\x cm,-0.1cm) {\Year};
};
\end{tikzpicture}
\footnotetext{foo}
\end{document}


• Thanks a lot @egreg! So easy and it explains everything. I will remember to avoid TeX primitives in the future. – nathanori Apr 9 '13 at 8:11
• Hey @egreg, there is a follow-up question: How do I use multiple footnotemark / footnotetext pairs without errors? All footnotetext elements get the number of the last footnotemark. The output displays a "footnote has been referenced but does not exist, replaced by a fixed one" error. The problem is caused by the hyperref package. – nathanori Apr 9 '13 at 9:14
• @nathanori If I were you, I'd avoid footnotes; the caption is the best place for explanations. – egreg Apr 9 '13 at 9:45
• @nathanori In any case, you have to "step back" the footnote counter; see tex.stackexchange.com/a/43694/4427 – egreg Apr 9 '13 at 10:24
• Hey @egreg. Thank you very much for your suggestions! I took that into consideration and will try to find a better solution placing annotations = footnotes into the main text. – nathanori Apr 10 '13 at 10:13