Document Frameworks

\documentclass[a4paper]{article}

%% language and font encodings
\usepackage[english]{babel}
\usepackage[utf8x]{inputenc}
\usepackage[T1]{fontenc}

%% set page size and margins
\usepackage[a4paper,top=3cm,bottom=2cm,left=3cm,right=3cm,marginparwidth=1.75cm]{geometry}

%% define default sans font family for the document as roboto
%% sfdefault sets roboto as font for the main text
\usepackage[sfdefault, light, medium]{roboto}

\usepackage{float}						% package introducing floats like figure,...
\usepackage{listings}					% introduces source code listings with code highlighting
\usepackage{tikz}						% enables drawing awesome graphics directly with LaTex commands
\usetikzlibrary{arrows}					% tikz library for drawing arrows
\usepackage{xcolor}						% introduces lots of different (font) colors
\usepackage{amsmath}					% introduces most standard math environments and commands
\usepackage{graphicx}					% package needed to insert graphic objects like images
\usepackage[colorinlistoftodos]{todonotes} % introduces a simple method of inserting TODO notes in the document
\usepackage[colorlinks=true, allcolors=blue]{hyperref} % introduces hyperlinks in the document

%% styling of section titles
\usepackage{titlesec}
%% design for section and subsection headings
\titleformat{\section}[hang]{\normalfont\Large}{\thesection}{0.5em}{}[]
\titleformat{\subsection}[hang]{\normalfont\large}{\thesubsection}{0.5em}{}[]

%% define style of tikz nodes for drawing graphs
\tikzset{
  treenode/.style = {align=center, inner sep=8pt, text centered,
    font=\sffamily},
  arn_n/.style = {treenode, circle, black, draw=black,
    text width=1.5em},
}

%% define listing style for shell languages
\lstdefinestyle{myshell}{
  basicstyle=\small\ttfamily,
  numbers=none,
  frame=tblr,
  columns=fullflexible,
  backgroundcolor=\color{blue!10},
  linewidth=\linewidth
}

%% define a basic styling for a language listing e.g. for python (which is defined in the actual listing)
\lstset{
  backgroundcolor=\color{blue!10},  	% choose the background color
  basicstyle=\ttfamily,        			% size of fonts used for the code
  breaklines=true,                 		% automatic line breaking only at whitespace
  captionpos=b,                    		% sets the caption-position to bottom
  frame=tblr,
  commentstyle=\color{purple},    		% comment style
  keywordstyle=\color{blue},      		% keyword style
  stringstyle=\color{red},     			% string literal style
}

%% remove indents at the beginning of a paragraph in whole file
\setlength\parindent{0pt} 

%% specify, how many % floats have to make up in a page that the page becomes a float only page
\renewcommand{\floatpagefraction}{.8}%

% set title and author of the document
\title{This is the document title}
\author{This is the author of the document}

\begin{document}
\maketitle
\section{This is a section heading}
\label{sec:sectionheading}

The document is just a basic framework including enough functionality for most purposes.\newline

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\newline

\subsection{This is a subsection heading}
\label{subsec:subsectionheading}

Here comes a reference to an image: fig.\ \ref{fig:image}. And here one for a code listing: lst.\ \ref{lst:script_t1}.
\newline

This is a reference a a section: sec.\ \ref{sec:sectionheading}.\newline

\begin{lstlisting}[style=myshell, caption={This is a sample listing for shell commands.}, label={lst:mn_setup1},captionpos=b]
sudo mn --custom MyTopo.py --topo MyTopo --controller=remote,ip=127.0.0.1,port=6633 --switch ovsk,protocols=OpenFlow13 --link tc
\end{lstlisting}

\begin{lstlisting}[language=Python, caption={Note that the shown code does not necessarily make sense ;-). Shows listing in Python.},label={lst:script_t1},captionpos=b]
  #!/usr/bin/python
  from  mininet.net   import Mininet

  class MyTopo( Topo ) :
      def __init__( self ) :
          # parent  class  Topo  initialization
          Topo.__init__( self )
          # Add hosts
          h1 = self.addHost ( 'h1', ip='172.31.1.1/24' )
          # Add switches
          s1 = self.addSwitch( 's1' )
          # Add links
          self.addLink( h1 , s1 , bw=100 )      
  topos = {'MyTopo':  (  lambda : MyTopo() )}

\end{lstlisting}

This is an example for a url:  \url{https://github.com/rkoenigstein}.\clearpage

Here comes a figure.\newline

\begin{figure}[htbp]
	\centering
	\includegraphics[width=1\textwidth]{sealion.jpg}
	\caption{Second SDN to be created}
	\label{fig:image}
\end{figure}

Here comes a graph generated with tikz:\newline

\begin{figure}[htbp]
  \centering
  \begin{tikzpicture}[->,>=stealth',level/.style={sibling distance = 3cm/#1,
    level distance = 2cm}]
  \node [arn_n] {root}
      child{ node [arn_n] {1}
          child{ node [arn_n] {5}
          }
          }
      child{ node [arn_n] {2}
          child{ node [arn_n] {6}
          }
          }
      child{ node [arn_n] {3}
          child{ node [arn_n] {7}
          }
          }
      child{ node [arn_n] {4}
          }
  ;
  \end{tikzpicture}
  \caption{Basic graph generated with the tikz package.}
  \label{fig:tikz_graph}
\end{figure}

\end{document}