# decoration nodes not being placed on the circle they are intended to be on

I "placed" some nodes on a circular path but they aren't showing up in the correct place and they aren't even on the circle.

What is going wrong?

\begin{document}

\usepackage{tikz, pgfplots}

\usetikzlibrary{arrows, decorations.markings, calc, fadings,  decorations.pathreplacing, patterns,decorations.pathmorphing, positioning}

\begin{document}
\begin{center}
\begin{tikzpicture}[line join = round, line cap = round, >=triangle 45]
\filldraw[blue, opacity = .3] (0,0) circle (2cm);
\draw[dashed] (-4,0) -- (5,0);
\begin{scope}[decoration = {markings, mark = at position 0.25 with {\arrow{>}},
mark = at position 0.75 with {\arrow{>}},
mark = at position 0.2 with {\node[draw, circle, inner sep = .05cm, fill = white
, scale = .75] {1};}, }]
\draw[postaction = decorate] (0,0) circle (2.5cm);
\filldraw[black] (2.5,0) circle (.05cm);
\node[scale = .75] at (2.7,.2) {$A$};
\end{scope}
\begin{scope}[decoration = {markings, mark = at position 0.25 with {\arrow{>}},
mark = at position 0.75 with {\arrow{>}},
mark = at position 0.2 with {\node[draw, circle, fill = white, inner sep = .05cm, scale = .75]
{2};},
mark = at position 0.35 with {\filldraw[black] circle (.05cm);}, } ]
\draw[postaction = decorate] (0,0) circle (3.75cm);
\end{scope}
\filldraw[black] (3.75,0) circle (.05cm);
\node[scale = .75] at (3.95,.2) {$B$};
\filldraw[black] (-3.75,0) circle (.05cm);
\node[scale = .75] at (-3.95,.2) {$C$};
\end{tikzpicture}
\end{center}
\end{document}

-

When using the mark option several times, positions should be given in ascending order:

\documentclass{article}
\usepackage{tikz}
\usetikzlibrary{arrows, decorations.markings, calc, fadings,  decorations.pathreplacing, patterns,decorations.pathmorphing, positioning}

\begin{document}
\begin{center}
\begin{tikzpicture}[line join = round, line cap = round, >=triangle 45]
\filldraw[blue, opacity = .3] (0,0) circle (2cm);
\draw[dashed] (-4,0) -- (5,0);
\begin{scope}[decoration = {markings,
mark = at position 0.2 with {\node[draw, circle, inner sep = .05cm, fill = white,   scale = .75] {1};},
mark = at position 0.25 with {\arrow{>}},
mark = at position 0.75 with {\arrow{>}}
}]
\draw[postaction = decorate] (0,0) circle (2.5cm);
\filldraw[black] (2.5,0) circle (.05cm);
\node[scale = .75] at (2.7,.2) {$A$};
\end{scope}
\begin{scope}[decoration = {markings,
mark = at position 0.2 with {\node[draw, circle, fill = white, inner sep = .05cm, scale = .75] {2};},
mark = at position 0.25 with {\arrow{>}},
mark = at position 0.35 with {\filldraw[black] circle (.05cm);},
mark = at position 0.75 with {\arrow{>}}
}]
\draw[postaction = decorate] (0,0) circle (3.75cm);
\end{scope}
\filldraw[black] (3.75,0) circle (.05cm);
\node[scale = .75] at (3.95,.2) {$B$};
\filldraw[black] (-3.75,0) circle (.05cm);
\node[scale = .75] at (-3.95,.2) {$C$};
\end{tikzpicture}
\end{center}
\end{document}


Quoting directly from Section 30.5 Arbitrary Markings (page 328) of the pgfmanual:

It is possible to give the mark option several times, which causes several markings to be applied. In this case, however, it is necessary that the positions on the path are in increasing order. That is, it is not allowed (and will result in chaos) to have a marking that lies earlier on the path to follow a marking that is later on the path.

-
so that is the issue only issue then? –  dustin Mar 30 '13 at 1:52
@dustin yes; that was the problem. –  Gonzalo Medina Mar 30 '13 at 1:54