Minimal Example of LaTeX file using lstlistings to produce formatted Octave code with highlighting

latexCodeHighlight.tex

\documentclass[xcolor=dvipsnames]{beamer}
\usepackage{graphics, listings}

\definecolor{gray}{rgb}{0.85,0.85,0.85}
\lstset{frame=single,
	basicstyle=\tiny,backgroundcolor=\color{gray},
	language=Octave,
	keywordstyle=\color{blue},
	stringstyle=\color{BrickRed},
	commentstyle=\color{OliveGreen}}

\begin{document}
	    
\begin{frame}[fragile]
\frametitle{Algorithm for Determining Maxima}

\begin{lstlisting}
function xopt = golden(xl, xu, tol)

  R  = (sqrt(5) - 1)/2             % golden ratio
  d  = R * (xu - xl)
  
  x1 = xl + d; f1 = f(x1)
  x2 = xu - d; f2 = f(x2)
  
  while (xu - xl > tol)
  
    d = R * d                      % interval shrinks by factor R
    
    if (f1 > f2)
      xl = x2
      x2 = x1
      x1 = xl + d
      f2 = f1
      f1 = f(x1)
    else
      xu = x1
      x1 = x2
      x2 = xu - d
      f1 = f2
      f2 = f(x2)  
    endif	     
      
  endwhile
  
  xopt = (xu + xl)/2  
  
endfunction
\end{lstlisting}

\end{frame}

\end{document}