header.tex

% Allowing for slides with 2 columns
\def\begincols{\begin{columns}[c]}
\def\endcols{\end{columns}}
\def\begincol{\begin{column}{0.5\textwidth}}
\def\endcol{\end{column}}

% Reducing black space between R code and output
% \setlength{\topsep}{0pt}{}
\setlength{\emergencystretch}{0em}
\setlength{\parskip}{2pt}
\setlength{\partopsep}{1pt}

% Reducing font size of R code and output
% Code below from http://stackoverflow.com/a/38324868
% See also http://stackoverflow.com/a/39961605

% Change fontsize of R code
\let\oldShaded\Shaded
\let\endoldShaded\endShaded
\renewenvironment{Shaded}{\footnotesize\oldShaded}{\endoldShaded}

% Change fontsize of output
\let\oldverbatim\verbatim
\let\endoldverbatim\endverbatim
\renewenvironment{verbatim}{\footnotesize\oldverbatim}{\endoldverbatim}