Die *Standard-Anker* kann man sich mit folgendem Schaubild klarmachen:
[![alt text][1]][2]
text][1]][1]
\documentclass[border=5mm]{standalone}
\usepackage{tikz}
\begin{document}
\begin{tikzpicture}[x=2cm, y=2cm,
every node/.style={draw, fill=yellow!50, opacity=0.5, text opacity=1}
]
\draw [help lines, step=2cm] (0,0) grid (3,2);
\fill (0,0) circle (2pt) node[anchor=north]{north};
\fill (1,0) circle (2pt) node[anchor=east]{east};
\fill (2,0) circle (2pt) node[anchor=south]{south};
\fill (3,0) circle (2pt) node[anchor=west]{west};
\fill (0,1) circle (2pt) node[anchor=north east]{north east};
\fill (1,1) circle (2pt) node[anchor=south east]{south east};
\fill (2,1) circle (2pt) node[anchor=south west]{south west};
\fill (3,1) circle (2pt) node[anchor=north west]{north west};
\fill (0,2) circle (2pt) node[anchor=mid]{mid};
\fill (1,2) circle (2pt) node[anchor=center]{center};
\fill (2,2) circle (2pt) node[anchor=base]{base};
\end{tikzpicture}
\end{document}
____
Daneben gibt es weitere Anker. Gleichwohl lassen sich mit Ankern spezifische Koordinaten ansteuern; hier am Beispiel eines `rectangle`:
[![alt text][2]][2]
text][2]][3]
%\documentclass[]{article}
\documentclass[border=5mm, varwidth]{standalone}
\usepackage{tikz}
\begin{document}
\begin{tikzpicture}[
every node/.style={font=\ttfamily\scriptsize},
mystyle/.style={gray, thin},
]
\node[name=s,gray, rectangle, draw,mystyle, minimum width=5cm, minimum height=3cm] {};
\draw[mystyle] (s.north) -- (s.south);
\draw[mystyle] (s.east) -- (s.west);
\draw[mystyle] (s.north east) -- (s.south west);
\draw[mystyle] (s.south east) -- (s.north west);
\draw[] plot[mark=x] coordinates{(s.center)} node[above]{(s.center)};
\draw[] plot[mark=x] coordinates{(s.north)} node[above]{(s.north)};
\draw[] plot[mark=x] coordinates{(s.east)} node[right]{(s.east)};
\draw[] plot[mark=x] coordinates{(s.south)} node[below]{(s.south)};
\draw[] plot[mark=x] coordinates{(s.west)} node[left]{(s.west)};
\draw[] plot[mark=x] coordinates{(s.north east)} node[right]{(s.north east)};
\draw[] plot[mark=x] coordinates{(s.south east)} node[right]{(s.south east)};
\draw[] plot[mark=x] coordinates{(s.south west)} node[left]{(s.south west)};
\draw[] plot[mark=x] coordinates{(s.north west)} node[left]{(s.north west)};
\end{tikzpicture}
\begin{tikzpicture}[
every node/.style={font=\ttfamily\scriptsize},
mystyle/.style={gray, thin},
]
\node[name=s,gray, rectangle, draw,mystyle, minimum width=5cm, minimum height=3cm, text=gray, font=\normalsize] {\vrule width 1pt height 2cmRectangle};
\draw[mystyle] (s.base west) -- (s.base east);
\draw[] plot[mark=x] coordinates{(s.center)} node[above]{(s.center)};
\draw[blue] plot[mark=x] coordinates{(s.mid)} node[above]{(s.mid)};
\draw[] plot[mark=x] coordinates{(s.base)} node[below]{(s.base)};
\draw[] plot[mark=x] coordinates{(s.base west)} node[left]{(s.base west)};
\draw[] plot[mark=x] coordinates{(s.base east)} node[right]{(s.base east)};
\draw[blue] plot[mark=x] coordinates{(s.mid west)} node[right]{(s.mid west)};
\draw[blue] plot[mark=x] coordinates{(s.mid east)} node[left]{(s.mid east)};
\end{tikzpicture}
\centering\begin{tikzpicture}[
every node/.style={font=\ttfamily\scriptsize},
mystyle/.style={gray, thin},
]
\node[name=s,gray, rectangle, draw,mystyle, minimum width=5cm, minimum height=3cm, text=gray, font=\normalsize] {\vrule width 1pt height 2cmRectangle};
\draw[mystyle] (s.west) -- (s.east);
\draw[mystyle] (s.base west) -- (s.base east);
\draw[] plot[mark=x] coordinates{(s.center)} node[above]{(s.center)};
\draw[] plot[mark=x] coordinates{(s.text)} node[left]{(s.text)};
\draw[] plot[mark=x] coordinates{(s.-10)} node[right]{(s.-10)};
\draw[] plot[mark=x] coordinates{(s.90)} node[above]{(s.90)};
\draw[] plot[mark=x] coordinates{(s.130)} node[above]{(s.130)};
\end{tikzpicture}
\end{document}
[1]: http://texwelt.de/wissen/upfiles/55555555_109.png
http://texwelt.de/wissen/upfiles/55555555_112.png
[2]: http://texwelt.de/wissen/upfiles/55555555_111.png
[3]: http://texwelt.de/wissen/upfiles/55555555_111.png