I wish to draw a graph with two loops undirected on the same vertice, follows the figure:
I draw the two loops, but got ugly, follows the code:
\begin{tikzpicture}
\draw[fill=black] (2,-1) circle (3pt);
\draw[fill=black] (2,0) circle (3pt);
\draw[fill=black] (2,2) circle (3pt);
\node at (2.5,-1) {$z$};
\node at (2.4,0.1) {$x.y$};
\node at (2,2.3) {$w$};
\draw[thick] (2,0) edge[bend right] (2,2);
\draw[thick] (2,0) edge[bend left] (2,2);
\draw[thick] (2,-1) edge[bend right] (2,0);
\draw[thick] (2,-1) edge[bend left] (2,0);
\draw (2,0) edge [loop left] (2,0);
\draw (2,0) edge [loop below] (2,0);
\end{tikzpicture}