I'm trying to draw a complex contour, using Tikz, for my dissertation due in a few days. Here are two crude drawings of what I'm aiming for:
To do so, I have adapted the code from this thread.
\documentclass[border=10pt,tikz,multi]{standalone}\usetikzlibrary{decorations.markings}\begin{document}\begin{tikzpicture} [ decoration={% markings, mark=at position 0.5 with {\arrow[line width=1pt]{>}}, } ] \draw [help lines,->] (-4,0) -- (4,0) coordinate (xaxis); \draw [help lines,->] (0,-1) -- (0,4) coordinate (yaxis); \node at (1,0) {$\times$}; \node at (-1,0) {$\times$}; \path [draw, line width=0.8pt] (1.5,0) node [below, font=\scriptsize] {$1+\epsilon$} -- (3,0) node [below] {$R$} arc (0:180:3) node [below] {$-R$} -- (-1.5,0) node [below, font=\scriptsize] {$1-\epsilon$} arc (180:0:.5); \path [draw, line width=0.8pt] (-0.5,0) -- (0.5, 0) node [below, font=\scriptsize] {$1-\epsilon$} arc (180:0:.5); \path [draw, line width=0.8pt, postaction=decorate] (1.5,0) node [below, font=\scriptsize] {$1+\epsilon$} -- (3,0) node [below] {$R$} arc (0:180:3) node [below] {$-R$} -- (-1.5,0) ; arc (180:0:.5); \node [below] at (xaxis) {$Re(z)$}; \node [left] at (yaxis) {$Im(z)$}; \node [below left] {$O$}; \node at (-1,.8) {$\gamma_{1}$}; \node at (1,.8) {$\gamma_{2}$}; \node at (2,3) {$\Gamma_{1}$};\end{tikzpicture}
I would greatly appreciate some help to:
Remove 1-\varepsilon and 1+\varepsilon. I've been playing aroundwith the code but I'm not sure which parts to remove as I get errorswhen removing the term!
Adding arrows to the contours like in my drawings. When I've tried to add arrows, it's been adding multiple arrows in one area of the contour.
- Adding the -1 and 1 below the poles.
- Replicating the contour in the lower half plane to give Figure 2.
Additionally is it possible to make the subscripts for lower case gamma to look more visibly like subscripts? Thanks so much in advance.