How to add a “noze” to an axis?

I want to add an arbitrary length to an axis, but I don't know how.

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

\pgfkeys{/tikz/.cd,
Noze/.store in=\Noze,
Noze=.5cm,
}

\begin{document}

\begin{tikzpicture}[%

\draw [->] (0,0)--(1+\Noze,0)  ;

\pgfmathsetmacro\result{2 + \x / 10}
\node[above=1pt,text depth=1.5pt]  at (\x)%
{\pgfmathprintnumber[precision=1,fixed,use comma]{\result}};

} ;

\end{tikzpicture}
\end{document}

-
I found this : \draw [->] (0,0)--(1,0)-- ++(\Noze,0) ; that works. – Tarass Feb 15 '14 at 12:21
Well, Paulo Cereda made an effort here, but it's probably not what you look for ;) chat.stackexchange.com/transcript/message/13789779#13789779 – yo' Feb 15 '14 at 13:20
Exactly what I was looking for ! It became my online image. How to thank him ? ;-) – Tarass Feb 15 '14 at 14:24

You can use calc library:

\documentclass[10pt,a4paper,french]{article}
\usepackage{tikz}
\usetikzlibrary{calc}

\pgfkeys{/tikz/.cd,
Noze/.store in=\Noze,
Noze=2.5cm,
}

\begin{document}

\begin{tikzpicture}[%

\draw [->] (0,0)--($(1,0) +(\Noze,0)$)  ;