%% 
%%  A DANTE-Edition example
%% 
%%  Example 02-26-1 on page 104.
%% 
%%  Copyright (C) 2010 Herbert Voss
%% 
%%  It may be distributed and/or modified under the conditions
%%  of the LaTeX Project Public License, either version 1.3
%%  of this license or (at your option) any later version.
%% 
%%  See http://www.latex-project.org/lppl.txt for details.
%% 
%% 
%% ==== 
% Show page(s) 1
%% 
\documentclass[]{article}
\pagestyle{empty}
\setlength\textwidth{375.57637pt}
\usepackage[utf8]{inputenc}

\usepackage{siunitx,booktabs}

\begin{document}
\sisetup{table-figures-integer=2,table-figures-decimal=4}
\begin{tabular}{S | % default column setting
                S[table-number-alignment=center] |
                S[table-number-alignment=right]  |
                S[table-number-alignment=left, output-decimal-marker={,}]}\toprule
\emph{default}&\emph{centred}&\emph{right-aligned}&\emph{left-aligned}\\\midrule
 2.3456 &  2.3456 &  2.3456 &  2.3456 \\
34.25   & 34.25   & 34.25   & 34.25   \\
 6.7835 &  6.7835 &  6.7835 &  6.7835 \\
90.473  & 90.473  & 90.473  & 90.473  \\\bottomrule
\end{tabular}
\end{document}