[Tex/LaTex] Create beautiful table with diagonally splitted cell or another creative idea avoiding this division

Question

I have this table in hands and I want to make it more appealing.

I have a trouble with the \ in the first cell of the table, and all solutions that I found here in tex.stackexchange are not beautiful nor inspire me for other solutions.

What do you recommend me to do here, to avoid splitting the first cell in two diagonal parts?
Or please present me some creative idea with the \ that divides the cell…

Thanks in advance.

Answer 1

I propose one of these:

    \documentclass[11pt,pdftex, a4paper]{article}
    \usepackage[utf8]{inputenc}
    \usepackage[T1]{fontenc}
    \usepackage{lmodern}
    \usepackage{amsmath, diagbox, hhline, booktabs}
    \usepackage[table, x11names, svgnames]{xcolor}

    \begin{document}

        \begin{tabular}{|c|*{3}{>{$}c<{$}|}}
          \hline
          \diagbox[linewidth=0.2pt, width=\dimexpr \textwidth/10+2\tabcolsep\relax, height=0.6cm]{$\enspace\boldsymbol \alpha $}{$\;\boldsymbol \beta $}
   & -1 & 0 & 1 \\
          \hline
          $ -1 $ & 0& -1 & -2\\
          \hline
          $ 0 $ & 1 & 0 &-1 \\
          \hline
           $ 1 $ & 2 & 1 & 0 \\
          \hline
        \end{tabular}
    \bigskip

     \begin{tabular}{!{\color{IndianRed3} \vrule}c !{\color{IndianRed3}\vrule\,\vrule}*{2}{>{$}c<{$}!{\color{Lavender}\vrule}} >{$}c<{$}!{\color{IndianRed3}\vrule}}%
     \arrayrulecolor{IndianRed3}
              \hhline{-||---}
          \diagbox[linecolor=Lavender, linewidth=0.3pt, width=\dimexpr \textwidth/10+2\tabcolsep\relax, height=0.6cm]{$ \enspace\boldsymbol \alpha $}{$\;\boldsymbol \beta $}
   & -1 & 0 & 1 \\
          \hhline{=::===}
          $ -1 $ & 0& -1 & -2\\
 \hhline{|>{\arrayrulecolor{Lavender}}->{\arrayrulecolor{IndianRed3}}||>{\arrayrulecolor{Lavender}}--->{\arrayrulecolor{IndianRed3}}|}
          $ 0 $ & 1 & 0 &-1 \\
          \hhline{|>{\arrayrulecolor{Lavender}}-||--->{\arrayrulecolor{IndianRed3}}|}
           $ 1 $ & 2 & 1 & 0 \\
     \arrayrulecolor{IndianRed3}
          \hhline{-||---}
        \end{tabular}

    \bigskip

 $ \setlength\extrarowheight{3pt} \begin{array}{c @{\,}>{\columncolor{Thistle3}[0pt][6pt]}r!{\mkern 2mu}|*{3}{c|}}
         \multicolumn{2}{c}{ } & \multicolumn{3}{c}{\boldsymbol \beta }\\
        \rowcolor {LightPink2!50}\multicolumn{1}{c}{\cellcolor{white}} &\multicolumn{1}{c!{\mkern4mu}}{\cellcolor{Plum4}} & \multicolumn{1}{c}{-1} & \multicolumn{1}{c}{0} & \multicolumn{1}{c}{1} \\
        \addlinespace[0.5ex]
        \cline{3-5}
        & -1 & 0& -1 & -2\\
        \cline{3-5}
         \boldsymbol \alpha & 0 & 1 & 0 &-1 \\
        \cline{3-5}
             & 1 & 2 & 1 & 0 \\
        \cline{3-5}
        \end{array} $
   \end{document}