Text overflows bottom of page using multicols and longtable

Question

I'm having an issue with text overflowing the page length even though I'm using the geometry package to do my setup, as shown in:

I can overcome this by adding a increased bmargin parameter to geometry, but I'm thinking there might be an underlying problem here that needs fixing.

This suspicion is reinforced, somewhat, by a gap between some text and tikz table/diagrams which seems to vary in size in different places in the final document, for example:

I wonder if this might have something to do with some vbox code that wraps a longtable to make it work properly in a multicolumn? That was copied from environment to balance a table in a multicol and it is way beyond my ken, I'm afraid.

Code to demonstrate problem:

\documentclass[a4paper]{article}
\usepackage[a4paper, margin=5mm]{geometry}
\pagenumbering{gobble}
\usepackage[T1]{fontenc}
\usepackage{tgadventor}
\renewcommand{\familydefault}{\sfdefault}
\usepackage[english]{babel}
\usepackage{ragged2e}
%\setlength\parindent{0pt}
\usepackage[parfill]{parskip}
\newcommand{\veryshortdummytext}{short dummy text.}
\newcommand{\shortdummytext}{short dummy text short dummy text short dummy text short dummy text short dummy text.}
\usepackage[x11names]{xcolor}
\usepackage{tikz} 
\usetikzlibrary{positioning, shapes.misc, shapes,arrows,chains, arrows.meta, calc, decorations.pathmorphing}
\usepackage{multirow}
\usepackage{array}
\usepackage{makecell}
\renewcommand{\cellalign}{cl}
\usepackage{lipsum}
\usepackage{layout}
\usepackage{longtable} 
\usepackage{multicol}
\usepackage{ifthen}
\usepackage{textcomp}
\usepackage{xkeyval}
\usepackage{xkvview}
\setlength\parindent{0pt}
\colorlet{ColIn1}{Blue1}

\colorlet{ColIgnored1}{Blue1!20}

\colorlet{ColIn2}{Red1}

\colorlet{ColIgnored2}{Red1!20}

\colorlet{ColOut}{Magenta3}

\colorlet{ColIgnored3}{Magenta3!20}
\tikzset{ 
    operation/.style={
        rounded rectangle, minimum size=6mm, 
        thick, draw=black, 
        font=\ttfamily 
    },
    Register/.style={
        rectangle,
        minimum height = 1cm,
        minimum width = 8cm,

    },
    point/.style={circle, inner sep=0pt, minimum size=2pt, fill=red},
    sizenode/.style = {font=\fontsize{20}{20}\selectfont\bfseries\sffamily, white},
    node distance = 5mm and 10mm, 
    >=Kite, 
    every node/.style={transform shape}, 
}
\newcommand\Register[2]{ % location, caption
    \draw [thick]

        (#1) +(0cm,0cm) -- +(8cm,0cm)  -- +(8cm,1cm)  -- +(0cm,1cm) -- cycle;
\draw [thick]         
    (#1) +(0,0)  +(4,0) -- +(4,1);

\draw [thin, dashed]  
    (#1) +(0,0)  +(2,0) -- +(2,1)  +(6,0) -- +(6,1); 

\draw [very thin, dotted]  
    (#1) +(0,0)  +(1,0) -- +(1,1)  +(3,0) -- +(3,1)
         +(5,0) -- +(5,1)  +(7,0) -- +(7,1);

\path (#1) +(0,1) node [above right] {#2};         

}
\newcommand\RegisterFull[5][32]{
    \fill [#3] (#2.south west) +(0,0) rectangle +(4,1);

    \fill [#4] (#2.south west) +(4,0) rectangle +(8,1);
\Register{#2.south west}{#5}
\node [sizenode] at ($ (#2.south west) + (60mm, 5mm) $) {#1};

}
\newcommand\RRFullFull[2][]{
    \node (r1before) [Register] {};
    \RegisterFull{r1before}{ColIgnored1}{ColIn1}{};
\node [Register, below=of r1before] (r1after) {};
\RegisterFull{r1after}{ColIgnored1}{ColOut}{}

\draw [black, dotted, rounded corners] 
    ($ (r1after.south west) - (0.2,0.2) $) rectangle  ($ (r1before.north east) + (0.2,0.2) $);
\path (r1before.south west) ++(0,1.0) +(0,0.2) node [above right] {R\textsubscript{1}};  

\node (op) [operation, right=of r1before]   {#2};

\node [Register, right= of op] (r2) {};
\RegisterFull{r2}{ColIgnored2}{ColIn2}{R\textsubscript{2}}

\draw [-&gt;,thick,ColIn1]   (r1before.east) -- (op);
\draw [-&gt;,thick,ColIn2] (r2.west) -- (op);
\draw [-&gt;,thick,rounded corners,ColOut]  (op) |- (r1after.east);    

\ifthenelse{\equal{#1}{}}{}{
    \node (bit) [ccbit, below right = 10mm and 10mm of op]  {#1};
    \draw [-&gt;,thick,black] (bit.north west) -- (op);
}

}
\def\add{\raisebox{-1.2em}{\LARGE{+}}}
\newcommand{\inst}[1]{\textbf{#1}}
\newcommand\Wrap[1]{
    \scalebox{0.3}{
        \begin{tikzpicture}[ scale=1.0, baseline=(current bounding box.center)]  % .north
            #1
            \useasboundingbox 
                ([shift={(0mm,2mm)}]current bounding box.north east) 
                rectangle 
                ([shift={(0mm,-2mm)}]current bounding box.south west);
        \end{tikzpicture}
    }
}
\newsavebox\ltmcbox
\setlength{\columnsep}{3.5mm}

\begin{document}
\section*{xxx}
\begin{FlushLeft}
\begin{multicols*}{2}
\textbf{Author:} \shortdummytext
\textbf{Version:} \shortdummytext
\subsection*{Notes}
\shortdummytext
\textbf{Notation:} \shortdummytext \shortdummytext \shortdummytext

\begin{itemize}
    \item \shortdummytext \shortdummytext \shortdummytext

    \item \shortdummytext \shortdummytext 

    \item \shortdummytext \shortdummytext 

    \item \shortdummytext \shortdummytext  

    \item\shortdummytext \shortdummytext 

    \item \shortdummytext \shortdummytext 

    \item \shortdummytext 

    \item \shortdummytext 
\end{itemize}

\textbf{Program exceptions:} \shortdummytext 


\section*{xxx}
\subsection*{xxx}
\setlength{\columnsep}{2mm} 
    \begin{list}{}{}
        \item \veryshortdummytext
        \item \veryshortdummytext
        \begin{tabular}[t]{@{}l@{\hspace{1mm}}l@{}}
            0 &amp; \veryshortdummytext \\
            1 &amp; \veryshortdummytext \\
            2 &amp; \veryshortdummytext \\
            3 &amp; \veryshortdummytext \\
        \end{tabular}
    \item This line is missing
    \begin{itemize}
        \item \veryshortdummytext
    \end{itemize}
\end{list}

\setbox\ltmcbox\vbox{
    \makeatletter\col@number\@ne
    \small
    \begin{longtable}[t]{@{}l@{\hspace{1mm}}l@{\hspace{1mm}}c@{}}
        \inst{AR} &amp; 
        R\textsubscript{1},R\textsubscript{2} &amp;
        \Wrap{\RRFullFull{\add}} \\

        \inst{AR} &amp; 
        R\textsubscript{1},R\textsubscript{2} &amp;
        \Wrap{\RRFullFull{\add}} \\         

        \inst{AR} &amp; 
        R\textsubscript{1},R\textsubscript{2} &amp;
        \Wrap{\RRFullFull{\add}} \\         

        \inst{AR} &amp; 
        R\textsubscript{1},R\textsubscript{2} &amp;
        \Wrap{\RRFullFull{\add}} \\         

        \inst{AR} &amp; 
        R\textsubscript{1},R\textsubscript{2} &amp;
        \Wrap{\RRFullFull{\add}} \\         

        \inst{AR} &amp; 
        R\textsubscript{1},R\textsubscript{2} &amp;
        \Wrap{\RRFullFull{\add}} \\         

        \inst{AR} &amp; 
        R\textsubscript{1},R\textsubscript{2} &amp;
        \Wrap{\RRFullFull{\add}} \\         

        \inst{AR} &amp; 
        R\textsubscript{1},R\textsubscript{2} &amp;
        \Wrap{\RRFullFull{\add}} \\         

        \inst{AR} &amp; 
        R\textsubscript{1},R\textsubscript{2} &amp;
        \Wrap{\RRFullFull{\add}} \\         

        \inst{AR} &amp; 
        R\textsubscript{1},R\textsubscript{2} &amp;
        \Wrap{\RRFullFull{\add}} \\         

        \inst{AR} &amp; 
        R\textsubscript{1},R\textsubscript{2} &amp;
        \Wrap{\RRFullFull{\add}} \\         

        \inst{AR} &amp; 
        R\textsubscript{1},R\textsubscript{2} &amp;
        \Wrap{\RRFullFull{\add}} \\         

        \inst{AR} &amp; 
        R\textsubscript{1},R\textsubscript{2} &amp;
        \Wrap{\RRFullFull{\add}} \\         

        \inst{AR} &amp; 
        R\textsubscript{1},R\textsubscript{2} &amp;
        \Wrap{\RRFullFull{\add}} \\         

        \inst{AR} &amp; 
        R\textsubscript{1},R\textsubscript{2} &amp;
        \Wrap{\RRFullFull{\add}} \\         

        \inst{AR} &amp; 
        R\textsubscript{1},R\textsubscript{2} &amp;
        \Wrap{\RRFullFull{\add}} \\         

        \inst{AR} &amp; 
        R\textsubscript{1},R\textsubscript{2} &amp;
        \Wrap{\RRFullFull{\add}} \\         

        \inst{AR} &amp; 
        R\textsubscript{1},R\textsubscript{2} &amp;
        \Wrap{\RRFullFull{\add}} \\         

        \inst{AR} &amp; 
        R\textsubscript{1},R\textsubscript{2} &amp;
        \Wrap{\RRFullFull{\add}} \\         

        \inst{AR} &amp; 
        R\textsubscript{1},R\textsubscript{2} &amp;
        \Wrap{\RRFullFull{\add}} \\         

        \inst{AR} &amp; 
        R\textsubscript{1},R\textsubscript{2} &amp;
        \Wrap{\RRFullFull{\add}} \\         

    \end{longtable}
    \unskip
    \unpenalty
    \unpenalty
    }

\unvbox\ltmcbox


\subsection*{xxx}
\setlength{\columnsep}{2mm} 
\begin{list}{}{}
    \item This line is missing too
    \item \veryshortdummytext 222
\begin{tabular}[t]{@{}l@{\hspace{1mm}}l@{}}
    0 &amp; \veryshortdummytext \\
    1 &amp; \veryshortdummytext \\
    2 &amp; \veryshortdummytext \\
    3 &amp; \veryshortdummytext \\
\end{tabular}
\item \veryshortdummytext
\begin{itemize}
    \item \veryshortdummytext
\end{itemize}

\end{list}
\end{multicols*}
\end{FlushLeft} 
\end{document}

(I've provisionally tagged this with longtable and multicol as I've got use choose something, but that's only a guess! Do feel free to change as required.)

longtable basically does not support multicols The unvbox you show is a quick hack for simple cases but not very robust. You can help by adding \pagebreak or \newcolumn at suitable points — David Carlisle, Nov 24 '22 at 14:31
@DavidCarlisle: Many thanks. Is there a better way I should be doing long tables in multiple columns? — Ian, Nov 24 '22 at 14:53
er you could ask that the maintainers of longtable and multicol talk to each other, but we've only known each other for 30 years... Alternatively you could use supertab/xtab which will work but doesn't preserve column widths across breaks, not sure about newer packages such as longtblr from tabularray package — David Carlisle, Nov 24 '22 at 14:59
Note that multicols works by making one very long column then splitting it, which confuses longtable to no end. — John Kormylo, Nov 24 '22 at 19:18

Text overflows bottom of page using multicols and longtable

0 Answers0