could anyone help me to solve the following problem:
I want to draw a Hankel-Bromwich Contour in latex , anyone know how to correct the command?
\documentclass[a4paper,twoside,pdftex,11pt]{article}
\usepackage{amsmath,amssymb,amsfonts,amsthm,amscd}
\usepackage[lmargin=0.75in,rmargin=0.75in,tmargin=1in,bmargin=1in]{geometry}
\usepackage[pdftex]{graphicx}
\usepackage{tikz}
\usetikzlibrary{calc,decorations.markings,positioning}
\usepackage{scalefnt}
\usepackage{color}
\usepackage{hyperref}
\oddsidemargin 0cm \evensidemargin 0cm \pagestyle{myheadings}
\setlength{\abovedisplayskip}{0cm}
\setlength{\belowdisplayskip}{0cm} \topmargin -1cm
\parindent 0.5cm
\setlength{\parskip}{0pt}
\linespread{1.0}
\textwidth 16cm \textheight 24cm
\newtheorem{theorem}{Theorem}[section]
\newtheorem{lemma}[theorem]{Lemma}
\newtheorem{corollary}[theorem]{Corollay}
\newtheorem{definition}[theorem]{Definition}
\newtheorem{remark}[theorem]{Remark}
\numberwithin{equation}{section} \def\R{\mathbb{R}}
\allowdisplaybreaks[2]
\begin{document}
\vspace{-0.5cm}
\date{\small\it \today}
\begin{figure}[h]
\centering
{\scalefont{2.0}
\begin{tikzpicture}
%configurable parameters
\def\gap{0.4}
\def\bigradius{4}
\def\littleradius{1}
%axes
\draw[line width=2pt,->](-1.5*\bigradius,0) -- (1.5*\bigradius,0)
(0,-1.5*\bigradius) -- (0,1.5*\bigradius);
\draw[line width=2pt,->] (0,0)--(45:\littleradius);
%\draw[line width=2pt, ->](-135:\bigradius) -- (-135:\littleradius);
%\draw[line width=2pt,->](135:\littleradius) -- (135:\bigradius);
\draw[line width=2pt,->](0,0) -- (135:\bigradius); \node[above
right] at (45:\littleradius/1.5) {\large\bf{$\varepsilon$}};
\draw[line width=1pt,decoration={markings,
mark=at position 0.07 with{\arrow[line width =2pt]{>}},%{latex}},
mark=at position 0.17 with{\arrow[line width =2pt]{>}},
mark=at position 0.27 with{\arrow[line width =2pt]{>}},
mark=at position 0.35 with {\arrow[line width =2pt]{>}},%{latex}},
mark=at position 0.47 with{\arrow[line width =2pt]{>}},
mark=at position 0.53 with{\arrow[line width =2pt]{>}},%{latex}},
mark=at position 0.6 with {\arrow[line width =2pt]{>}},%{latex}},
mark=at position 0.65 with {\arrow[line width =2pt]{>}},%{latex}},
mark=at position 0.7 with{\arrow[line width =2pt]{>}},
mark=at position 0.8 with{\arrow[line width =2pt]{>}},
mark=at position 0.85 with{\arrow[line width =2pt]{>}},
mark=at position 0.955 with{\arrow[line width =2pt]{>}}},%{latex}}},
%mark=at position(45:\littleradius) with {arrow[line width=2pt]{>}}},
postaction={decorate}]
let
\n1={asin(\gap/2/\bigradius)},
\n2={asin(\gap/2/\littleradius)}
in (180-\n1:\bigradius) -- (-180-\n2:\littleradius)
arc(180-\n2:-180+\n2:\littleradius)--(-180+\n1:\bigradius)
arc(-180+\n1:-90:\bigradius)--(3,-4)--(3,4)--(0,4)arc(90:(180-\n1):\bigradius);
\coordinate (T) at (135:2); \node[above] at (T){$T$};
\coordinate(H) at (1.5*\bigradius,0); \node[below] at (H){\Large\bf {x}};
\coordinate (J) at (0,1.5*\bigradius); \node[left] at (J){$\Large\bf y$};
\coordinate (C) at (\littleradius,0); \node[below
right] at (C) {\Large\bf {C}};
\coordinate (D)at(180-{asin(\gap/2/\littleradius)}:1); \node[above left] at (D) {$ \Large\bf B$};
\coordinate (E) at(-180+{asin(\gap/2/\littleradius)}:1); \node[below left] at (E) {$\Large\bf D$};
\coordinate (F) at(180-{asin(\gap/2/\bigradius)}:\bigradius); \node[above left] at (F) {$\Large\bf A$};
\coordinate (G) at(-180+{asin(\gap/2/\bigradius)}:\bigradius); \node[below left] at (G) {$\Large\bf E$};
\coordinate(P) at (0,-4); \node[below right]at (P) {$\Large\bf F$}; \coordinate(Q) at (3,-4); \node[right] at(Q) {$\Large\bf G(\gamma-iT)$};
\coordinate(R) at (3,4); \node[right] at (R) {$\Large\bf H(\gamma+iT)$};
\coordinate(S) at (0,4);\node[above right] at (S) {$\Large\bf K$};
\end{tikzpicture}
}
\end{document}
I wanna draw the picture like this
