我有一张表格，我想根据小数位对齐数字，同时数字仍然居中。我尝试使用 siunitx 包，但没有成功 :(
非常感谢您的帮助！（数据不是真实的）
\usepackage[format=plain,
labelfont=it,
textfont=it]{caption}
\usepackage{array}
\usepackage{siunitx}
\usepackage{booktabs}
\usepackage{multicol}
\usepackage{multirow}
\usepackage{tabu}
\usepackage{booktabs}
\usepackage[tableposition=top]{caption}
\begin{document}
\begin{table}[hbt!]
\centering
\caption{Time measurements for oil samples with different weights of additive X for 40 and 60$^\circ C$. Dynamic viscosity is then calculated using the viscometer constant, $C$.}
\begin{tabular}[t]{c c c c c c}
\toprule
Concentration (wt\%) & $T$ ($^\circ$C) & \multicolumn{3}{c}{$t$ ($s$, $\pm1$)} & Dynamic Viscosity ($cP$, $\pm0.1$)\\
& & 1$^{\text{st}}$ & 2$^{\text{nd}}$ & 3$^{\text{rd}}$ & \\
\midrule
\multirow{2}{*}{0}& 40 & 10 & 10 & 10 & 68.3 \\
& 60 & 10 & 10 & 10 & 4.3 \\ \\
\multirow{2}{*}{1.875}& 40 & 10 & 10 & 10 & 42.3\\
& 60 & 10 & 10 & 10 & 3.2\\ \\
\multirow{2}{*}{2.5}& 40 & 10 & 10 & 10 & 31.4\\
& 60 & 10 & 10 & 10 & 4.9\\ \\
\multirow{2}{*}{5}& 40 & 10 & 10 & 10 & 12.2\\
& 60 & 10 & 10 & 10 & 13.0\\ \\
\multirow{2}{*}{7}& 40 & 10 & 10 & 10 & 43.2\\
& 60 & 10 & 10 & 10 & 1.0\\
\bottomrule
\end{tabular}
\label{tab:my_label}
\end{table} ```
答案1
除了将数据列中的数字与其（显式或隐式）小数点对齐之外，您还应尝试 (a) 通过在标题单元格中提供合适的换行符使表格更紧凑，以及 (b) 更仔细地排版科学单位和相关数量。借助包的\unit和\qty宏，可以轻松实现后一个目标siunitx。
\documentclass{article}
\usepackage[format=plain,font=it,tableposition=top]{caption}
\usepackage{array,siunitx,booktabs,amsmath}
\newcolumntype{T}[1]{S[table-format=#1]}
\newcommand\mytab[1]{%
\smash[b]{\begin{tabular}[t]{@{}c@{}} #1 \end{tabular}}}
\begin{document}
\begin{table}[hbt!]
\centering
\caption{Time measurements for oil samples with different weights of
additive~X for \qty{40}{\celsius} and \qty{60}{\celsius}. Dynamic
viscosity is then calculated using the viscometer constant $C$.}
\label{tab:my_label}
\begin{tabular}{@{} T{1.3} *{4}{T{2.0}} T{2.1} @{}}
\toprule
\mytab{Concentration\\(wt \%)} &
\mytab{Temp.\\(\unit{\celsius})} &
\multicolumn{3}{c}{Time (\unit{\second}, $\pm1$)} &
\mytab{Dynamic viscosity\\($cP$, $\pm0.1$)}\\
\cmidrule(lr){3-5}
&& {1\textsuperscript{st}} & {2\textsuperscript{nd}} & {3\textsuperscript{rd}} \\
\midrule
0 & 40 & 10 & 10 & 10 & 68.3\\
& 60 & 10 & 10 & 10 & 4.3\\
\addlinespace
1.875 & 40 & 10 & 10 & 10 & 42.3\\
& 60 & 10 & 10 & 10 & 3.2\\
\addlinespace
2.5 & 40 & 10 & 10 & 10 & 31.4\\
& 60 & 10 & 10 & 10 & 4.9\\
\addlinespace
5 & 40 & 10 & 10 & 10 & 12.2\\
& 60 & 10 & 10 & 10 & 13.0\\
\addlinespace
7 & 40 & 10 & 10 & 10 & 43.2\\
& 60 & 10 & 10 & 10 & 1.0\\
\bottomrule
\end{tabular}
\end{table}
\end{document}
答案2
使用tabularray包（版本 2022B）及其库booktabs（用于表规则）和siunitx（用于S列类型，其中数字在小数点对齐）加载同名的包：
\documentclass{article}
\usepackage[format=plain,
labelfont=it,
textfont=it]{caption}
\usepackage{tabularray}
\UseTblrLibrary{booktabs, siunitx}
\ExplSyntaxOn
\NewChildSelector{eachtwo}
{
\int_step_inline:nnnn {3}{2}{\l_tblr_childs_total_tl}
{ \clist_put_right:Nn \l_tblr_childs_clist {##1} }
}
\ExplSyntaxOff
\begin{document}
\begin{table}[hbt!]
\centering
\caption{Time measurements for oil samples with different weights of
additive~X for \qty{40}{\celsius} and \qty{60}{\celsius}. Dynamic
viscosity is then calculated using the viscometer constant $C$.}
\label{tab:my_label}
\begin{tblr}{colspec = {@{} S[table-format=1.3]
*{4}{S[table-format=2.0]}
S[table-format=2.1] @{}},
row{1,2} = {guard},
row{3-Z} = {rowsep=0pt},
row{eachtwo} = {abovesep=4pt}
}
\toprule
\SetCell[r=2]{c} {Concentration\\(wt \%)}
& \SetCell[r=2]{c} {Temp.\\(\unit{\celsius})}
& \SetCell[c=3]{c} Time (\unit{\second}, $\pm1$)
& & & \SetCell[r=2]{c} {Dynamic viscosity\\($cP$, $\pm0.1$)} \\
\midrule
& & {1\textsuperscript{st}}
& {2\textsuperscript{nd}}
& {3\textsuperscript{rd}}
& \\
\midrule
0 & 40 & 10 & 10 & 10 & 68.3 \\
& 60 & 10 & 10 & 10 & 4.3 \\
1.875 & 40 & 10 & 10 & 10 & 42.3 \\
& 60 & 10 & 10 & 10 & 3.2 \\
2.5 & 40 & 10 & 10 & 10 & 31.4 \\
& 60 & 10 & 10 & 10 & 4.9 \\
5 & 40 & 10 & 10 & 10 & 12.2 \\
& 60 & 10 & 10 & 10 & 13.0 \\
7 & 40 & 10 & 10 & 10 & 43.2 \\
& 60 & 10 & 10 & 10 & 1.0 \\
\bottomrule
\end{tblr}
\end{table}
\end{document}
