centered large plot in beamer

plot_example.tex

\documentclass{beamer}

\usepackage{amsmath}
\usepackage{amsfonts}
\usepackage{booktabs}
\usepackage{mathtools}
\mathtoolsset{showonlyrefs}

%% no idiotic nav buttons
\setbeamertemplate{navigation symbols}{}
\setlength\abovedisplayskip{0pt}
\setlength\belowdisplayskip{0pt}

\usepackage{url}
\usepackage{booktabs}
\usepackage{graphicx}

\begin{document}

\begin{frame}
  \begin{center}
    \includegraphics[width=\textwidth]{/tmp/plot.pdf} % replace filename
  \end{center}
\end{frame}

\end{document}