how to make cellcolor not fill the cell completely

Question

\documentclass[]{article}
\usepackage[utf8x]{inputenc}
\usepackage[english]{babel}
\usepackage[T1]{fontenc}
\usepackage{amsmath,amsthm,amsfonts,amssymb}
\usepackage{graphicx}
\usepackage{floatrow}
\usepackage{subfig}
\usepackage{microtype}
\usepackage{braket}
\usepackage{physics}
\usepackage{bm}
\usepackage{scalefnt}
\usepackage{asymptote}
\usepackage{asypictureB}
\usepackage{float}
\usepackage{makecell}

\usepackage[all,cmtip]{xy}
\usepackage{thmtools,thm-restate}
\usepackage[shortlabels]{enumitem}
\usepackage{xcolor,colortbl}
\makeatletter 
\def\l@subsubsection#1#2{}
\makeatother
\usepackage{tikz}
\usetikzlibrary{calc}
\usepackage{zref-savepos}
\usepackage{tabu}
\newcommand*\circled[1]{\tikz[baseline=(char.base)]{% <---- BEWARE
\node[shape=circle,draw,inner sep=2pt] (char) {#1};}}

\begin{document}

\begin{table}[H]
    \centering
\begin{tabular}{c|c|c}
    \circled{A}
    & \circled{B}
    & \circled{C}
          \\ \hline
    \cellcolor{red!25}{p$_1$} & \cellcolor{red!25}{p$_1$}   & \cellcolor{red!25}{p$_1$}          \\ \hline
    \cellcolor{red!25}{p$_2$}& \cellcolor{red!25}{p$_2$}    & \cellcolor{red!25}{p$_2$}  \\ \hline
    \cellcolor{red!25}{p$_3$}  & 
 \cellcolor{red!25}{p$_3$}   & \cellcolor{red!25}{p$_3$}
\end{tabular}
\end{table}
\end{document}

The above code creates the following table.

Is it possible to make the cell coloring not merge with the neighboring cells such that the text in the cell has the colored background but there is still some white spacing between the neighboring cells in both vertical and horizontal directions?

Answer 1

With {NiceTabular} of nicematrix.

\documentclass{article}
\usepackage{nicematrix,tikz}

\newcommand*\circled[1]{\tikz[baseline=(char.base)]{% <---- BEWARE
\node[shape=circle,draw,inner sep=2pt] (char) {#1};}}

\begin{document}

\begin{NiceTabular}{ccc}[cell-space-limits=1mm]
\CodeBefore 
  \begin{tikzpicture}
  \fill [red!15] (2-|1) rectangle (5-|4) ; 
  \begin{scope} [color = white, line width = 2 pt]
    \draw (2-|1) -- (2-|4) (3-|1) -- (3-|4) (4-|1) -- (4-|4) ; 
    \draw (2-|2) -- (5-|2) (2-|3) -- (5-|3) ; 
  \end{scope}
  \draw (2-|1) -- (2-|4) (3-|1) -- (3-|4) (4-|1) -- (4-|4) ; 
  \draw (1-|2) -- (5-|2) (1-|3) -- (5-|3) ; 
  \draw [color = white, line width = 2 pt] (1-|1) rectangle (5-|4) ;
  \end{tikzpicture}
\Body
  \circled{A} & \circled{B} & \circled{C} \\
    p$_1$ & p$_1$ & p$_1$ \\
    p$_2$ & p$_2$ & p$_2$ \\
    p$_3$ & p$_3$ & p$_3$
\end{NiceTabular}

\end{document}

You need several compilations (because nicematrix uses PGF/Tikz nodes under the hood).

Answer 2

Is it possible ... to [have] some white spacing between the neighboring cells in both vertical and horizontal directions?

You could execute \arrayrulecolor{white} to achieve your typesetting objective.

\documentclass{article}
%%\usepackage[utf8x]{inputenc} % that's the default nowadays
\usepackage[english]{babel}
\usepackage[T1]{fontenc}
\usepackage{xcolor,colortbl}

\usepackage{tikz}
\usetikzlibrary{calc}
\newcommand*\circled[1]{\tikz[baseline=(char.base)]{% <---- BEWARE
   \node[shape=circle,draw,inner sep=2pt] (char) {#1};}}

\begin{document}

\begin{table}[h]
\arrayrulecolor{white}
\arrayrulewidth=2\arrayrulewidth % double the width of the rules

\centering
\begin{tabular}{c|c|c}
    \circled{A} & \circled{B} & \circled{C} \\ 
    \hline
    \cellcolor{red!25}p\textsubscript{1} & 
    \cellcolor{red!25}p\textsubscript{1} & 
    \cellcolor{red!25}p\textsubscript{1} \\ 
    \hline
    \cellcolor{red!25}p\textsubscript{2} & 
    \cellcolor{red!25}p\textsubscript{2} & 
    \cellcolor{red!25}p\textsubscript{2} \\ 
    \hline
    \cellcolor{red!25}p\textsubscript{3} & 
    \cellcolor{red!25}p\textsubscript{3} & 
    \cellcolor{red!25}p\textsubscript{3} 
\end{tabular}
\end{table}
\end{document}

Answer 3

Like this ?

With tabularay

\documentclass{article}
\usepackage{tabularray}
\usepackage{tikz}
\usetikzlibrary{calc}
\newcommand*\circled[1]{\tikz[baseline=(char.base)]{% <---- BEWARE
\node[shape=circle,draw,inner sep=2pt] (char) {#1};}}

\begin{document}
\begin{tblr}{
  colspec = { *{3}c },
  hline{2-Y} = {1pt,solid},
  vline{2-Y} = {1pt,solid},
  row{2-Z} = {cmd=\colorbox{red!25}}
  }
  \circled{A} & \circled{B} & \circled{C}\\ 
  p$_1$ & p$_1$ & p$_1$ \\
  p$_2$ & p$_2$ & p$_2$ \\
  p$_3$ & p$_3$ & p$_3$ \\
\end{tblr}
\end{document}

EDIT : with tabularray, i think the answer of zarko is better (if you replace p1 by d1, \strut with \colorbox don't work).

Another solution with tikz

EDIT2: To make it look a little nicer, but unlike F. Pantigny's answer with nicematrix, you have to adjust the width of the rectangles manually, if the columns are not the same width.

THE CODE:

    \documentclass{article}
    \usepackage{tabularray}
    \usepackage{tikz}
    \newcommand*\circled[1]{\tikz[baseline=(char.base)]{% <---- BEWARE
    \node[shape=circle,draw,inner sep=2pt] (char) {#1};}}

    \newcommand*\rect[1]{\tikz[baseline=(char.base)]{% <---- BEWARE
    \node[inner sep=2pt,fill=red!25,minimum width=2em] (char) {\strut$#1$};}}

    \begin{document}
    \begin{tblr}{
    colspec = { *{3}{Q[wd=2em,c]} },
    hline{2-Y} = {1pt,solid},
    vline{2-Y} = {1pt,solid},
    row{1} = {cmd=\circled},
    row{2-Z} = {cmd=\rect},
    rowsep=1pt,
    colsep=1pt
    }
    A & B & C\\ 
    p_1 & p_1  & d_1 \\
    p_2 & p_2  & d_2 \\
    p_3 & p_3  & d_3 \\
    \end{tblr}
    \end{document}

Answer 4

A small variation of nice @pascal answer (+1):

• defined is command for coloring box behind cells content
• table body is in math mode

\documentclass[border=3.141592]{standalone}
\usepackage{tikz}
\usepackage{tabularray}
\UseTblrLibrary{amsmath}

\newcommand*\circled[1]{\tikz[baseline=(char.base)]{% <---- BEWARE
                        \node[shape=circle,draw,inner sep=2pt] (char) {#1};}}
\makeatletter   % https://tex.stackexchange.com/questions/522350/
    \newcommand{\cb}[3]{\fcolorbox{#2}{#1}{\m@th$\displaystyle#3$}}
\makeatother

\begin{document}
\begin{tblr}{hline{2-Y} = {1pt}, vline{2-Y} = {1pt},
             colspec = { *{3}{Q[c]} },
             colsep  = {2pt},
             row{2-Z}= {cmd=\cb{red!30}{red!30}}
            }
\circled{A} & \circled{B} & \circled{C}\\
  p_1 & p_1 & p_1 \\
  p_2 & p_2 & p_2 \\
  p_3 & p_3 & p_3 \\
\end{tblr}
\end{document}