Long text in rotated multirow

Question

I created a minimal example with the bad table in red.

\documentclass{article}
\usepackage{siunitx} % To align the numbers later on
\usepackage{booktabs}
\newcommand{\ra}[1]{\renewcommand{\arraystretch}{#1}}
\usepackage{multirow}
\usepackage{rotating}

\begin{document}
    \begin{table*}[t]
        \newcommand{\rot}[1]{\rotatebox{90}{#1}}
        \newcommand{\multirot}[1]{\multirow{2}{*}{\rot{#1}}}
        \centering
        \ra{1.3}
        \begin{tabular}{ccc} \toprule
            \multirot{Minimal example} &
            \multicolumn{2}{c}{Minimal} \\
            \cmidrule{2-3}
            & exa & mple \\ \midrule
            a & a & 10 \\
            a & a & 0.1 \\
            a & a & 0.001 \\ \bottomrule
        \end{tabular}
    \end{table*}
\end{document}

Why does the top left cell not get bigger, when the content exceeds the height of the two rows on the top right? The text "Minimal example" should be aligned at the bottom (so multiple columns like that will flatter on the top).

How to I achieve a table similar to the one on the right in my example image?

• I implemented this question, but it only works for short text.
• I saw this question, but feel like using a table in a table will make it overly complex.

Answer 1

It is simple with makecellandt its \rotcell command, if you accept a two-lined column head. I took the opportunity to use siunitx for the last column.

\documentclass{article}
\usepackage{siunitx} % To align the numbers later on
\usepackage{booktabs}
\newcommand{\ra}[1]{\renewcommand{\arraystretch}{#1}}
\usepackage{multirow, makecell}
\usepackage{rotating}
\settowidth\rotheadsize{Minimal}

\begin{document}
\begin{table*}[t]
  \newcommand{\rot}[1]{\rotatebox{90}{#1}}
  \newcommand{\multirot}[1]{\multirow{2}{*}{\rot{#1}}}
  \centering
  \ra{1.3}
  \begin{tabular}{@{\,}ccS[table-format=2.3]} \toprule
    \multirow{2}{*}[1.5ex]{\rotcell{Minimal example}}&
    \multicolumn{2}{c}{Minimal} \\
    \cmidrule{2-3}
      & exa & {mple} \\[0.5ex] \midrule
    a & a & 10 \\
    a & a & 0.1 \\
    a & a & 0.001 \\ \bottomrule
  \end{tabular}
\end{table*}
\end{document} 

Answer 2

Ok, I took Bernhards answer as a started and created two possible solutions for future reference.

I kept the second one with a longer heading, because all columns with rotated headings remain the same width.

\documentclass{article}
\usepackage{siunitx} % To align the numbers later on
\usepackage{booktabs}
\newcommand{\ra}[1]{\renewcommand{\arraystretch}{#1}}
\usepackage{multirow, makecell}
\usepackage{rotating}
\settowidth\rotheadsize{Minimal}

\begin{document}
    \begin{table*}[t]
        \newcommand{\rot}[1]{\rotatebox{90}{#1}}
        \newcommand{\multirot}[1]{\multirow{2}{*}[1.5ex]{\rotcell{#1}}}
        \centering
        \ra{1.3}
        \begin{tabular}{@{\,}cccS[table-format=2.3]} \toprule
            \multirot{Short} &
            \multirot{Extended} &
            \multicolumn{2}{c}{Minimal} \\
            \cmidrule{3-4}
            && exa & {mple} \\[0.5ex] \midrule
            a & a & a & 10 \\
            a & a & a & 0.1 \\
            a & a & a & 0.001 \\ \bottomrule
        \end{tabular}
    \end{table*}

    \begin{table*}[t]
        \newcommand{\multirot}[1]{\multirow{2}{*}[1.5ex]{\rotcell{\rlap{#1}}}}
        \centering
        \ra{1.3}
        \begin{tabular}{@{\,}cccS[table-format=2.3]} \toprule
            \multirot{Short} &
            \multirot{Long Example} &
            \multicolumn{2}{c}{Minimal}\rule{0pt}{1.3cm} \\
            \cmidrule{3-4}
            && exa & {mple} \\[0.5ex] \midrule
            a & a & a & 10 \\
            a & a & a & 0.1 \\
            a & a & a & 0.001 \\ \bottomrule
        \end{tabular}
    \end{table*}
\end{document}

I am happy with the optical results (both versions), but I am not happy that I needed \settowidth\rotheadsize{Minimal} for the second table to work although is not related to this.

Feel free to edit my solution or comment it.