vertical alignment/ table/ text/math

Question

I want to create a table with text and math symbols in its cells. The problem is that I want in each cell the context to be vertically aligned to center.

Below you can see what I have done so far

\documentclass[a4paper,12pt]{report}

\usepackage{amsmath}
\usepackage{amsthm}
\usepackage{amssymb}
\usepackage{amsfonts}

\usepackage[table]{xcolor}

\begin{document}

   \newcolumntype{K}{>{\centering}m{4.5cm}}
   \newcolumntype{L}{>{\centering}m{3.5cm}}
   \newcolumntype{M}{@{}m{0pt}@{}}

   \begin{tabular}{|c|K|c|c|L|M|}
      \multicolumn{2}{c}{\cellcolor{cyan}\textbf{Column A}} &  &  \multicolumn{2}{c}{\cellcolor{cyan}\textbf{Column B}}\\[5pt]
      a.  & $5x^3(x - 1)^3$, $2x(x - 1)^4$   &  & 1. & $-10x^4(x - 1)^3$ &\\[20pt]
      \hline        
      b.  & $5x(x - 1)^2$, $2x^3(x - 1)$     &  & 2. & $10x^2(x - 1)$ &\\[20pt]
      \hline            
      c.  & $5x^4(x^2 - 1)$, $2x^2(x - 1)^2$  &  & 3. & $10x^2(x - 1)^4$ &\\[20pt]
      \hline            
      d.  & $5x^2(x - 1)^2$, $2x^4(1 - x)^3$ &  & 4. & $10x^3(x - 1)^2$ &\\[20pt]
      \hline        
      c.  & $\dfrac{x^2}{x + 1}$                       &  & 5. & $10x^4(x - 1)^2(x + 1)$ &\\
      \hline
   \end{tabular}

\end{document}

As you can see the text in the first row isn't vertically aligned. Any suggestions?

Answer 1

You can fake it by adding an extra line at the top, in the form of

\multicolumn{2}{c|}{\cellcolor{cyan}} &  &  \multicolumn{2}{c}{\cellcolor{cyan}}\\[-5pt]

Here is the MWE. I also changed the leading multi-column format to c| to make the vertical black lines symmetrical abutting the cyan border.

\documentclass[a4paper,12pt]{report}

\usepackage{amsmath}
\usepackage{amsthm}
\usepackage{amssymb}
\usepackage{amsfonts}

\usepackage[table]{xcolor}

\begin{document}

   \newcolumntype{K}{>{\centering}m{4.5cm}}
   \newcolumntype{L}{>{\centering}m{3.5cm}}
   \newcolumntype{M}{@{}m{0pt}@{}}

   \begin{tabular}{|c|K|c|c|L|M|}
      \multicolumn{2}{c|}{\cellcolor{cyan}} &  &  \multicolumn{2}{c}{\cellcolor{cyan}}\\[-5pt]
      \multicolumn{2}{c|}{\cellcolor{cyan}\textbf{Column A}} &  &  \multicolumn{2}{c}{\cellcolor{cyan}\textbf{Column B}}\\[5pt]
      a.  & $5x^3(x - 1)^3$, $2x(x - 1)^4$   &  & 1. & $-10x^4(x - 1)^3$ &\\[20pt]
      \hline        
      b.  & $5x(x - 1)^2$, $2x^3(x - 1)$     &  & 2. & $10x^2(x - 1)$ &\\[20pt]
      \hline            
      c.  & $5x^4(x^2 - 1)$, $2x^2(x - 1)^2$  &  & 3. & $10x^2(x - 1)^4$ &\\[20pt]
      \hline            
      d.  & $5x^2(x - 1)^2$, $2x^4(1 - x)^3$ &  & 4. & $10x^3(x - 1)^2$ &\\[20pt]
      \hline        
      c.  & $\dfrac{x^2}{x + 1}$                       &  & 5. & $10x^4(x - 1)^2(x + 1)$ &\\
      \hline
   \end{tabular}

\end{document}

If you wanted that last row fixed up too, use the stackengine package and employ an \addstackgap[]{} with the $\dfrac{x^2}{x + 1}$entry:

      c.  & \addstackgap{$\dfrac{x^2}{x + 1}$}  &  & 5. & $10x^4(x - 1)^2(x + 1)$ &\\

to achieve

Answer 2

m columns lose baseline alignment so I wouldn't use them for short one-line examples. here I've simplified the table markup getting rid of the "extra" columns, and just opening up the table a bit. I left in the full width \hline as you have them, but I'd be tempted to make them not cross the middle, or just not have the lines at all.

\documentclass[a4paper,12pt]{report}

\usepackage{amsmath}
\usepackage{amsthm}
\usepackage{amssymb}
\usepackage{amsfonts}

\usepackage[table]{xcolor}

\begin{document}

   \newcolumntype{K}{>{\centering\arraybackslash}p{4.5cm}}
   \newcolumntype{L}{>{\centering\arraybackslash}p{3.5cm}}

   {\renewcommand\arraystretch{2.5}%
   \begin{tabular}{|c|K|@{\hspace{1cm}}|c|L|}
      \hline
      \multicolumn{2}{|c|@{\hspace{1cm}}|}{\cellcolor{cyan}\textbf{Column A}} & 
    \multicolumn{2}{c|}{\cellcolor{cyan}\textbf{Column B}}\\
      \hline
      a.  & $5x^3(x - 1)^3$, $2x(x - 1)^4$   &  1. & $-10x^4(x - 1)^3$ \\
      \hline
      b.  & $5x(x - 1)^2$, $2x^3(x - 1)$     &  2. & $10x^2(x - 1)$ \\
      \cline{1-2}\cline{3-4}          
      c.  & $5x^4(x^2 - 1)$, $2x^2(x - 1)^2$  &  3. & $10x^2(x - 1)^4$ \\
      \hline            
      d.  & $5x^2(x - 1)^2$, $2x^4(1 - x)^3$ &  4. & $10x^3(x - 1)^2$ \\
      \hline        
      c.  & $\dfrac{x^2}{x + 1}$             & 5. & $10x^4(x - 1)^2(x + 1)$ \\
      \hline
   \end{tabular}}

\end{document}

Answer 3

The simplest way to have vertically centred cells is with the cellspacepackage: it defines (globally) minimal vertical spacing above and below cell contents in columnx with specifier prefixed with the letter S (or C if you load siunitx).

The following code uses only c or Sccolumns. Additionally, I used \hhlines, and added a line under the coloured column heads, as I found it neater:

\documentclass[a4paper,12pt]{report}

\usepackage{amsmath}
\usepackage{amsthm}
\usepackage{amssymb}
\usepackage{array, cellspace, hhline}
\setlength\cellspacetoplimit{15pt}
\setlength\cellspacebottomlimit{15pt}
\usepackage[table]{xcolor}

\begin{document}

   \begin{tabular}{|*{2}{Sc|}p{2em}*{2}{|Sc}|}
      \multicolumn{2}{Sc}{\cellcolor{cyan}\textbf{Column A}} & & \multicolumn{2}{>{\columncolor{cyan}[6.4pt][6pt]}c}{\cellcolor{cyan}\textbf{Column B}}\\
      \hhline{--~|--}
      a. & $5x^3(x - 1)^3$, $2x(x - 1)^4$ & & 1. & $-10x^4(x - 1)^3$ \\
      \hhline{--~|--}
      b. & $5x(x - 1)^2$, $2x^3(x - 1)$ & & 2. & $10x^2(x - 1)$ \\
      \hhline{--~|--}
      c. & $5x^4(x^2 - 1)$, $2x^2(x - 1)^2$ & & 3. & $10x^2(x - 1)^4$ \\
      \hhline{--~|--}
      d. & $5x^2(x - 1)^2$, $2x^4(1 - x)^3$ & & 4. & $10x^3(x - 1)^2$ \\
      \hhline{--~|--}
      c. & $\smash{\dfrac{x^2}{x + 1}}$ & & 5. & $10x^4(x - 1)^2(x + 1)$ \\
      \hhline{--~|--}
   \end{tabular}

\end{document}