Make codecell a no-op environment to allow page breaks in cells.

preamble.tex

@@ -1,98 +1,112 b''
 %% This is the automatic preamble used by IPython.  Note that it does *not*
 %% include a documentclass declaration, that is added at runtime to the overall
 %% document.
 
 \usepackage{amsmath}
 \usepackage{amssymb}
 \usepackage{graphicx}
 \usepackage{ucs}
 \usepackage[utf8x]{inputenc}
 
 % needed for markdown enumerations to work
 \usepackage{enumerate}
 
 % Slightly bigger margins than the latex defaults
 \usepackage{geometry}
 \geometry{verbose,tmargin=3cm,bmargin=3cm,lmargin=2.5cm,rmargin=2.5cm}
 
 % Define a few colors for use in code, links and cell shading
 \usepackage{color}
 \definecolor{orange}{cmyk}{0,0.4,0.8,0.2}
 \definecolor{darkorange}{rgb}{.71,0.21,0.01}
 \definecolor{darkgreen}{rgb}{.12,.54,.11}
 \definecolor{myteal}{rgb}{.26, .44, .56}
 \definecolor{gray}{gray}{0.45}
 \definecolor{lightgray}{gray}{.95}
 \definecolor{mediumgray}{gray}{.8}
 \definecolor{inputbackground}{rgb}{.95, .95, .85}
 \definecolor{outputbackground}{rgb}{.95, .95, .95}
 \definecolor{traceback}{rgb}{1, .95, .95}
 
 % Framed environments for code cells (inputs, outputs, errors, ...).  The
 % various uses of \unskip (or not) at the end were fine-tuned by hand, so don't
 % randomly change them unless you're sure of the effect it will have.
 \usepackage{framed}
 
 % remove extraneous vertical space in boxes
 \setlength\fboxsep{0pt}
 
 % codecell is the whole input+output set of blocks that a Code cell can
 % generate.
-\newenvironment{codecell}{%
-    \def\FrameCommand{\color{mediumgray} \vrule width 1pt \hspace{5pt}}%
-   \MakeFramed{\vspace{-0.5em}\FrameRestore}}
- {\unskip\endMakeFramed}
+
+% TODO: unfortunately, it seems that using a framed codecell environment breaks
+% the ability of the frames inside of it to be broken across pages.  This
+% causes at least the problem of having lots of empty space at the bottom of
+% pages as new frames are moved to the next page, and if a single frame is too
+% long to fit on a page, will completely stop latex from compiling the
+% document.  So unless we figure out a solution to this, we'll have to instead
+% leave the codecell env. as empty.  I'm keeping the original codecell
+% definition here (a thin vertical bar) for reference, in case we find a
+% solution to the page break issue.
+
+%% \newenvironment{codecell}{%
+%%     \def\FrameCommand{\color{mediumgray} \vrule width 1pt \hspace{5pt}}%
+%%    \MakeFramed{\vspace{-0.5em}}}
+%%  {\unskip\endMakeFramed}
+
+% For now, make this a no-op...
+\newenvironment{codecell}{}
 
  \newenvironment{codeinput}{%
    \def\FrameCommand{\colorbox{inputbackground}}%
    \MakeFramed{\advance\hsize-\width \FrameRestore}}
  {\unskip\endMakeFramed}
 
 \newenvironment{codeoutput}{%
    \def\FrameCommand{\colorbox{outputbackground}}%
    \vspace{-1.4em}
    \MakeFramed{\advance\hsize-\width \FrameRestore}}
  {\unskip\medskip\endMakeFramed}
 
 \newenvironment{traceback}{%
    \def\FrameCommand{\colorbox{traceback}}%
    \MakeFramed{\advance\hsize-\width \FrameRestore}}
  {\endMakeFramed}
 
 % Use and configure listings package for nicely formatted code
 \usepackage{listingsutf8}
 \lstset{
   language=python,
   inputencoding=utf8x,
   extendedchars=\true,
   aboveskip=\smallskipamount,
   belowskip=\smallskipamount,
   %xleftmargin=3mm,
   breaklines=true,
   basicstyle=\small \ttfamily,
   showstringspaces=false,
   keywordstyle=\color{blue}\bfseries,
   commentstyle=\color{myteal},
   stringstyle=\color{darkgreen},
   identifierstyle=\color{darkorange},
 }
 
 % The hyperref package gives us a pdf with properly built
 % internal navigation ('pdf bookmarks' for the table of contents,
 % internal cross-reference links, web links for URLs, etc.)
 \usepackage{hyperref}
 \hypersetup{
   breaklinks=true,  % so long urls are correctly broken across lines
   colorlinks=true,
   urlcolor=blue,
   linkcolor=darkorange,
   citecolor=darkgreen,
   }
 
 % hardcode size of all verbatim environments to be a bit smaller
 \makeatletter 
 \g@addto@macro\@verbatim\small\topsep=0.5em\partopsep=0pt
 \makeatother 
 
 % Prevent overflowing lines due to urls and other hard-to-break entities.
 \sloppy