Put left brace in nicematrix

bracesmatricesnicematrix

I want to have a matrix, where on the left side I have left brace with n written on it. But the current code I have does not produce the desired result. The left brace is not drawn due to some issue with SubMatrix, and moreover, submatrices \mathbf{A}_1 and \mathbf{A}_2 are moved one column to the right. Any idea how to do this?

\documentclass{article}
\usepackage{amsmath,nicematrix}
\begin{document}
\[ 
    \begin{bNiceArray}[last-col,margin]{w{c}{5em}|w{c}{3em}}
    \\
    \hspace*{-3cm} n & \mathbf{A}_1 & \mathbf{A}_2 \\
    \\
    \CodeAfter
    \OverBrace[yshift=5pt]{1-1}{2-2}{\mathbf{A}}
    \UnderBrace[yshift=5pt]{1-1}{3-1}{m_2}
    \UnderBrace[yshift=5pt]{2-2}{3-2}{m_1}
    \SubMatrix{\{}{1-1}{3-2}{.}[left-xshift=22pt]
    \end{bNiceArray}
\]
\end{document}

Best Answer

You probably wanted to use first-col and not last-col...

\documentclass{article}
\usepackage{nicematrix}
\begin{document}
\[ 
    \begin{bNiceArray}[first-col,margin]{w{c}{5em}|w{c}{3em}}
    \\
    n\hspace*{3mm} & \mathbf{A}_1 & \mathbf{A}_2 \\
    \\
    \CodeAfter
      \OverBrace[yshift=5pt]{1-1}{2-2}{\mathbf{A}}
      \UnderBrace[yshift=5pt]{1-1}{3-1}{m_2}
      \UnderBrace[yshift=5pt]{2-2}{3-2}{m_1}
      \SubMatrix{\{}{1-1}{3-2}{.}[left-xshift=27pt]
    \end{bNiceArray}
\]
\end{document}

Related Solutions

`nicematrix` NiceTabularX alignment

You don't seem to be making effective use of the various easily available spacing options. For instance, you could insert @{} at both ends of the tabular-like environment in order to eliminate any unwanted whitespace padding at the edges of the tabular-like environment.

The amount of intercolumn whitespace is given by 2\tabcolsep. To generate less of this whitespace, you can either set a smaller value for \tabcolsep (its default value is 6pt in most document classes), or you can state directly how much whitespace you're willing to allow between columns 1 and 2 -- by writing, say, @{\hspace{4pt}} if 4pt is the desired amount of whitespace.

I'm not sure if your real document makes further use of the machinery provided by the nicematrix package. As the following screenshot demonstrates, there's no difference between using a NiceTabularX environment or just a plain old tabularx environment, for the code you've provided.

Oh, please do use -- rather than - to generate typographic en-dashes between year groups.

\documentclass{book}
\usepackage{tabularx,nicematrix}
\usepackage{booktabs,lipsum}

\newcommand\blob{%
  \toprule
  \textbf{Year} & 
  \textbf{Important milestones or key achievements in de novo enzyme design}\\ 
  \midrule
  1983--84 & \lipsum[1][1-3] \\ \addlinespace[0.1em]
  1994     & \lipsum[1][1-3] \\ \addlinespace[0.1em]
  1995     & \lipsum[1][1-3] \\ \addlinespace[0.1em]
  2000--04 & \lipsum[1][1-3] \\ \addlinespace[0.1em]
  2010--14 & \lipsum[1][1-3] \\ \addlinespace[0.1em]
  \bottomrule}

\begin{document}

\begin{table}
\footnotesize

\begin{NiceTabularX}{\textwidth}{@{} l @{\hspace{4pt}} X @{}}
\blob
\end{NiceTabularX}

\bigskip

\begin{tabularx}{\textwidth}{@{} l @{\hspace{4pt}} X @{}}
\blob
\end{tabularx}

\end{table}

\end{document}

Nicematrix overbrace and underbrace clash with surrounding text

Here is a rather complicated workaround. Load tikz with the libraries decorations.pathreplacing and calligraphy. Then place the brace using \Hdotsfor{<num columns>} in row 1 (option first-row), but change the line-style using calligraphic brace.

\documentclass{article}
\usepackage{nicematrix, mathtools, tikz}
\usetikzlibrary{decorations.pathreplacing, calligraphy}
\tikzset{mybrace/.style={thick, decorate, decoration={calligraphic brace, amplitude=1.5mm, raise=-1mm}}}

\begin{document}
    A A A A A A A A A A A A A A A A A A A A A A A A A A A 
    \[
        \begin{pNiceMatrix}[first-row]
        \Hdotsfor{3}[line-style=mybrace, shorten=0pt]^{\textstyle A}&\Hdotsfor{3}[line-style={mybrace},shorten=0pt]^{\textstyle B}\\
        1 & 2 & 3 & 4 & 5 & 6 \\
        11 & 12 & 13 & 14 & 15 & 16
        \end{pNiceMatrix}
    \]
\end{document}

Best Answer

Related Solutions

`nicematrix` NiceTabularX alignment

Nicematrix overbrace and underbrace clash with surrounding text

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