Complex integration path diagram.

This diagram was made for my homework of Mathematical Physics at Drexel University during my Masters education The homework assignment can be found here at http://physics.drexel.edu/~pgautam/courses/

\begin{tikzpicture}
  [
    decoration={%
      markings,
      mark=at position 1cm with {\arrow[line width=1pt]{>}},
      %mark=at position 2cm with {\arrow[line width=1pt]{>}},
      mark=at position .3 with {\arrow[line width=1pt]{>}},
      mark=at position .6 with {\arrow[line width=1pt]{>}},
      mark=at position 0.8 with {\arrow[line width=1pt]{>}},
      mark=at position -5mm with {\arrow[line width=1pt]{>}},
    },
    contourline/.style={line width=1.0pt},
    axisline/.style={->,line width=0.3pt},
  ]
  \draw [axisline] (-4,0) -- (4,0) coordinate (xaxis) node [below,thick] {Re($z$)};
  \draw [axisline] (0,-0.6) -- (0,3.3) coordinate (yaxis) node [left,thick] {Im($z$)};
  \node at (0,0) {$\times$};
  \draw [contourline, postaction=decorate]
      (.5,0) node [below, font=\scriptsize] {$\epsilon$} --
      (3,0) node [below] {$R$}
      arc (0:180:3) node [below] {$-R$} --
      (-.5,0) node [below, font=\scriptsize] {$-\epsilon$}
      arc (180:0:.5);
  \node at (0.5,0.6) {$\Gamma_{\varepsilon}$};
  \node at (2,2.6) {$\Gamma_{R}$};
\end{tikzpicture}