\psset{xunit=0.75cm, yunit=1cm}
\begin{pspicture}(0,0)(11, 2)

\rput[c](4.2,1.5){$\vec{e_1}=\left(1,0,\ldots,0\right)$\hspace{5mm}\ldots\hspace{5mm}$\vec{e_i}=\left(0,\ldots,1,\ldots,0\right)$\hspace{5mm}\ldots\hspace{5mm}$\vec{e_n}=\left(0,\ldots,0,1\right)$}
%\psline[arrows=->](7.9,0.5)(7.9,1.2)
\psline[arrowlength=3, arrowinset=0.1, linecolor=red]{->}(4.65,0.5)(4.65,1.3)
\rput[c](4.65,0.2){\color{red}{i. Koordinate}}

%\rput[l](0,0){0,0}
%\rput[l](11,2){11,2}

\end{pspicture}
%rput center --> Koordianten werden um die x-Koordinate ausgerichtet