\upbracefill filling entire tabular cell and package colortbl

Question

In my documents, I have found that when I call \upbracefill in a tabular cell, the resulting brace IS NOT taking the entire width of the cell.

After creating the smallest example I could that produces this behavior (appended below), I have found that the problem has been the inclusion of the package colortbl.

When I remove this package from one of my documents, the brace resulting from \upbracefill DOES FILL the entire width of the cell.

For my documents, however, I need the package colortbl.

Attached is an example which replicates this behavior. You can try building this small document both ways, with and without the line \usepackage{colortbl}.

I need the normal behavior of \upbracefill to fill an entire cell. How can I do this with the package colortbl?

I am using LaTeX Version 3.1415926-2.6-1.40.14 (TeX Live 2014/dev)

\documentclass[letterpaper]{book}

\usepackage{colortbl} % TRY COMMENTING THIS OUT, TOO

\begin{document}

\begin{tabular}{  l llll llll }

letters: & a  & b & c & d & e & f & g & h  \\

blah          & \multicolumn{8}{c}{\upbracefill}    \\
blah          & \multicolumn{8}{l}{\upbracefill}    \\
\end{tabular}

\end{document}

score 3 · Answer 1 · edited Apr 13 '17 at 12:36

You can construct this \upbracefill manually:

enter image description here

\documentclass{article}

\usepackage{colortbl}

\begin{document}

\begin{tabular}{ *{9}{l} }
  letters: & a  & b & c & d & e & f & g & h  \\
  blah     & \multicolumn{8}{c}{\raisebox{.5\normalbaselineskip}[0pt][0pt]{$\underbrace{\phantom{abcdefgh}\hspace*{14\tabcolsep}}$}} \\
  blah     & \multicolumn{8}{l}{\raisebox{.5\normalbaselineskip}[0pt][0pt]{$\underbrace{\phantom{abcdefgh}\hspace*{14\tabcolsep}}$}} \\
\end{tabular}

\end{document}

Using a \phantom hides the equivalent column entries, while there are 2 \tabcolseps between each column. If the measurements become a little unwieldy, you can insert lengths to roughly match the width, like \hspace*{12.5em} in this case:

enter image description here

\documentclass{article}

\usepackage{colortbl}

\begin{document}

\begin{tabular}{ *{9}{l} }
  letters: & a  & b & c & d & e & f & g & h  \\
  blah     & \multicolumn{8}{c}{\raisebox{.5\normalbaselineskip}[0pt][0pt]{$\underbrace{\phantom{abcdefgh}\hspace*{14\tabcolsep}}$}} \\
  blah     & \multicolumn{8}{l}{\raisebox{.5\normalbaselineskip}[0pt][0pt]{$\underbrace{\hspace*{12.5em}}$}} \\
\end{tabular}

\end{document}

For more on horizontal widths, see What commands are there for horizontal spacing?

Mr. Grundlingh, please take a look at https://groups.google.com/forum/?hl=en#!topic/latexusersgroup/i-v1f3dVLjc — Josef J., Sep 20 '14 at 03:11
Thank you for your suggested work arounds. In addition, someone from latexproject.org sent me another work around, using the following command to make a bracket fill up an entire cell:
\def\hfill{\hskip0pt plus 1filll}\upbracefill

It can be confirmed that the package colortbl currently breaks \upbracefill, though colortbl currently is not part of the core latex release. — Josef J., Sep 26 '14 at 21:28

score 0 · Answer 2 · answered Oct 09 '23 at 09:04

With {NiceTabular} of nicematrix.

\documentclass[letterpaper]{book}
\usepackage{nicematrix}
% \usepackage{colortbl} % the output is the same with or without colortbl
\begin{document}
\begin{NiceTabular}{*{9}{l}}
  letters: & a  & b & c & d & e & f & g & h  \
  blah     & \
  blah     & \
\CodeAfter
  \UnderBrace[yshift=-2mm]{1-2}{2-9}{}
  \UnderBrace[yshift=-2mm]{1-2}{3-9}{}
\end{NiceTabular}
\end{document}

The output is the same with or without the package colortbl (however, nicematrix has its own tools to color cells, rows and columns).

\upbracefill filling entire tabular cell and package colortbl

2 Answers2