%%
%% The LaTeX Companion, 3ed
%%
%% Example 13-3-25 on page II-319 in "Numbering".
%%
%% Copyright (C) 2022 Frank Mittelbach
%%
%% It may be distributed and/or modified under the conditions
%% of the LaTeX Project Public License, either version 1.3c
%% of this license or (at your option) any later version.
%%
%% See https://www.latex-project.org/lppl.txt for details.
%%

\documentclass{tlc3exa}
\pagestyle{empty}
\setcounter{page}{6}
\setlength\textwidth{111.0pt}

%StartShownPreambleCommands
\usepackage[english,icelandic]{babel}
  \usepackage{dcolumn} \newcolumntype{d}{D{,}{\decimalsep}{-1}}
%StopShownPreambleCommands

\begin{document}
\tala{3141,592653}                           \par
\foreignlanguage{english}{\tala{3141,592653}}\par \bigskip
\begin{tabular}{|d|}  \hline
             3,14     \\
  \tala[,]{123,4567}  \\ \tala[,]{9876,543}  \\ \hline
\end{tabular}
\end{document}