http://cs.stackexchange.com/a/1112#figures.tex

%% pdflatex figures.tex && convert figures.pdf figures.png && for x in figures-*.png; do mogrify -crop 400x100+100+100 $x; done
\documentclass{article}
\usepackage{tikz}

\pagestyle{empty}

\makeatletter
\newcounter{x}
\newcommand{\hill}[1]{%
  \c@x=0
  \@for\y:=#1\do{
    \filldraw (\value{x},\y) ellipse (2pt and 4pt);
    \advance\c@x 1
  }
  \c@x=0
  \def\@tempa{\draw}
  \@for\y:=#1\do{
    \ifnum\the\c@x=0
    \else
      \edef\@tempa{\expandafter\noexpand\@tempa -- }
    \fi
      \edef\@tempa{\expandafter\noexpand\@tempa(\the\c@x,\y)}
    \advance\c@x 1
  }
  \@tempa;
}
\makeatother

\newenvironment{myfigure}{%
  \begin{tikzpicture}[yscale=0.5]
}{%
  \end{tikzpicture}
  \newpage
}

\begin{document}

\begin{myfigure}
  \hill{4,3,2,1,0}
\end{myfigure}

\begin{myfigure}
  \hill{4,3,2,1,2,3,2,1,0}
\end{myfigure}

\begin{myfigure}
  \hill{4,3,2,2.5,1.5,0.5,1,0}
\end{myfigure}

\begin{myfigure}
  \hill{3,2,1,3.5,2.5,1.5,0.5,-0.5,1.25,-0.25}
  \draw[red,dotted] (2,1) -- (8,1.25);
\end{myfigure}

\begin{myfigure}
  \hill{3,2,1,2.5,1.5,0.5,2,1,0}
  \draw[green,thick] (2,1) -- (4,1.5) -- (6,2);
\end{myfigure}

\begin{myfigure}
  \hill{2.1,3,2,1,2.5,1.5,0.5,2,1,0}
  \draw[green,thick] (3,1) -- (5,1.5) -- (7,2);
\end{myfigure}

\begin{myfigure}
  \hill{1,2,0,2.5,1.5,0.5}
  \draw[green,thick] (0,1) -- (1,2) -- (3,2.5);
\end{myfigure}

\end{document}