How do I define a list of strings with the babel package and the ngerman option?

Question

I try to make a pie chart, but can't get the labels right: This is the MWE:

\documentclass{article}
\usepackage[ngerman]{babel}
\usepackage{tikz}

\definecolorseries{colorser}{rgb}{last}{blue}{green}

\def\piechart#1#2#3#4#5{%1:data,2:numberOfElements,3:colors,4:outerRadius,5:labels
    \resetcolorseries[#2]{#3}
    \edef\startangle{90}
    \foreach [
        remember=\endangle as \startangle,
        evaluate=\i as \endangle using {\startangle-(\csname#1\endcsname[\i-1]/100*360)},
        evaluate=\halfangle using {(\endangle-\startangle)/2+\startangle},
    ] \i in {1,...,#2} {%
        \fill[{#3!![\i]}] (0,0) --++(\startangle:#4) arc (\startangle:\endangle:#4);
        \draw[white, line width=0.75mm](0,0)--++(\startangle:#4+0.1pt);
        \node at (\halfangle:#4) {\pgfmathparse{\csname#5\endcsname[\i-1]}\pgfmathresult};% With this line commented out there is no error...
    }
    \draw[white,line width=0.75mm](0,0)--++(\startangle:#4);
    \fill[white](0,0)circle [radius=#4*0.4];%
}

\begin{document}

\begin{tikzpicture}
    \newcommand\shares{{50,30,15,5}}
    \newcommand\labels{{"a","b","c","d"}}
    \piechart{shares}{4}{colorser}{2cm}{labels}
\end{tikzpicture}

\end{document}

This brings up the error

Argument of \language@active@arg" has an extra }. \par  ...piechart{shares}{4}{colorser}{2cm}{labels}

The output I hope for looks like that:

enter image description here

Without the labels, everything works...

score 3 · Answer 1 · answered Jun 08 '15 at 06:59

3

The active " is a babel shorthand, TikZ library babel helps:

\usepackage[ngerman]{babel}
\usepackage{tikz}
\usetikzlibrary{babel}

answered Jun 08 '15 at 06:59

Heiko Oberdiek

271,626

Well, I didn't expect this to come true that fast... Learned something already!! – caligula Jun 08 '15 at 07:14
For example that I can't use this library with TikZ/PGF < 3.0 :( see here – caligula Jun 08 '15 at 07:25

score 1 · Answer 2 · edited Apr 13 '17 at 12:35

It turned out that this comes from the babel package: The double quotation marks aren't recognized correctly. \shorthandoff{"} is the key here:

\shorthandoff{"}\newcommand\labels{{"a","b","c","d"}}\shorthandon{"}

Hope this helps someone, it cost me hours and hours. This helped me to find the solution and is slightly similar to this question, so I leave it up to you to mark this as duplicate or not. I think this question is the other way around and provides an error message that might be searched for...

How do I define a list of strings with the babel package and the ngerman option?

2 Answers2