The decimal marker in bold number is not align with asymmetrical number format in table.

[note286]

In the example in the 9.13 Tables with heading rows, the number is symmetrical, i.e., 3.3. But if we set a number like 3.6, the decimal marker are not aligned.

\documentclass{article}
\usepackage[table]{xcolor}
\usepackage{siunitx}
\begin{document}
\robustify\bfseries
\begin{tabular}
{@{}S[text-series-to-math, table-format = 3.3]@{}}
\rowcolor[gray]{0.9}
\bfseries 123.456 \\
23.45
\\
123.4
\\
3.456 \\
\end{tabular}
\qquad
\begin{tabular}
{@{}S[text-series-to-math, table-format = 3.6]@{}}
\rowcolor[gray]{0.9}
\bfseries 123.456789 \\
23.45
\\
123.4
\\
3.456 \\
\end{tabular}
\qquad
\begin{tabular}
{@{}S[text-series-to-math, table-format = 3.6]@{}}
\rowcolor[gray]{0.9}
\bfseries 123.456 \\
23.45
\\
123.4
\\
3.456789 \\
\end{tabular}
\end{document}

[josephwright]

I've thought about this a bit. The entire way that siunitx does alignment means we need to know the target width - which goes wrong if you have a variable font width. I think this really needs a feature to add formatting to the model.

[note286]

The current effect is still very satisfactory, just add table-model-setup=\bfseries. Here is the complete code below. But I suddenly found that if table-model-setup=\bfseries is used, then the decimal separator is not really centered. For the case of the first symmetric column, if table-model-setup=\bfseries is not added, it is true alignment. I don't know if there was a bug in table-model-setup's implementation.

\documentclass{article}
\usepackage[table]{xcolor}
\usepackage{siunitx}
\begin{document}
\robustify\bfseries
\begin{tabular}
{@{}S[text-series-to-math, table-format = 3.3, table-model-setup = \bfseries]@{}}
\rowcolor[gray]{0.9}
\bfseries 123.456 \\
23.45
\\
123.4
\\
3.456 \\
\end{tabular}
\qquad
\begin{tabular}
{@{}S[text-series-to-math, table-format = 3.6, table-model-setup = \bfseries]@{}}
\rowcolor[gray]{0.9}
\bfseries 123.456789 \\
23.45
\\
123.4
\\
3.456 \\
\end{tabular}
\qquad
\begin{tabular}
{@{}S[text-series-to-math, table-format = 3.6, table-model-setup = \bfseries]@{}}
\rowcolor[gray]{0.9}
\bfseries 123.456 \\
23.45
\\
123.4
\\
3.456789 \\
\end{tabular}
\end{document}

[josephwright]

I'm going to need to think about this one.