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\usepackage[a4paper, left=2cm, right=2cm, top=2cm, bottom=3cm]{geometry}

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\usepackage{amsmath,amssymb,amstext}
\usepackage{mathtools}
\usepackage{graphicx}
\usepackage{array,booktabs}
\usepackage{enumerate}
\usepackage{nicefrac}
\usepackage{tikz}
\usepackage{ifthen}
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\usepackage{icomma}
\usepackage{csquotes}
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\usepackage{esvect}
\usepackage[hidelinks]{hyperref}


\setlength{\parindent}{0pt}

\title{GGPLOT Dimensions of Plot}
\author{Arno Kimeswenger}
\date{\today}

\begin{document}

\maketitle

\begin{figure}[htpb]
  \centering
  \begin{minipage}{5.5cm}
    \centering
    \includegraphics{../my_first_plot_a}
    \caption{plot a, original width}
    \label{a}
  \end{minipage}
  \begin{minipage}{5.5cm}
    \centering
    \includegraphics[width=5cm]{../my_first_plot_b}
    \caption{plot b, scaled width}
    \label{b_scaled}
  \end{minipage}
  \begin{minipage}{8cm}
    \centering
    \includegraphics{../my_first_plot_b}
    \caption{plot b, original width}
    \label{b}
  \end{minipage}
  \begin{minipage}{5.5cm}
    \centering
    \includegraphics{../my_first_plot_g}
    \caption{plot g, original width}
    \label{g}
  \end{minipage}
\end{figure}

\begin{itemize}
\item In figure \ref{a} we see the original dimension of plot a ($5\times6$), in figure \ref{b_scaled} we have a small plot b ($2.5\times3$) which is scaled to $5\times6$. Therefore the textsize is large.
\item In figure \ref{b} we see the original dimension of plot b ($2.5\times3$), therefore the textsize is equal to figure \ref{a}.
\item In figure \ref{g} we see plot g with original dimension ($5\times6$). The textsize was set to $16$ in ggplot, so the textsize is larger than in plot \ref{a}.
\end{itemize}

\end{document}

