# Removing certain lines from a table

I have produced this table in LaTeX:

\begin{table}[hbt]
\begin{center}
\begin{tabular}{|l|l|l|l|}
\hline & \multicolumn{3}{c|}{Examples}\\
\cline{2-4}
& description & $M$ & \textbf{u}\\
\hline translation & through vector $\begin{pmatrix}6\\7\end{pmatrix}$ & $\begin{pmatrix} 1 & 0 \\ 0 & 1 \end{pmatrix}$ & $\begin{pmatrix}6\\7\end{pmatrix}$\\
\hline reflection & in line $x=2$ & $\begin{pmatrix} -1 & 0 \\ 0 & 1 \end{pmatrix}$ & $\begin{pmatrix}4\\0\end{pmatrix}$\\
\hline rotation & about \textbf{0} through $\pi$ radians & $\begin{pmatrix} -1 & 0 \\ 0 & -1 \end{pmatrix}$ & $\begin{pmatrix}0\\0\end{pmatrix}$\\
\hline glide reflection & in line $y=x$, then through $\begin{pmatrix}1\\1\end{pmatrix}$ & $\begin{pmatrix} 0 & 1 \\ 1 & 0 \end{pmatrix}$ & $\begin{pmatrix}1\\1\end{pmatrix}$\\
\hline
\end{tabular}
\caption{Examples of Euclidean Transformations} \label{tab1}
\end{center}
\end{table}


How do I remove the two external lines from the top left empty corner cell? I want lines only around the other parts.

Also it looks a bit cramped, is there a way I can present it more nicely?

• Welcome. You can modificate directly you table with tablesgenerator.com. It very simple and very fast. Can you add a screenshot? – Sebastiano Dec 9 '16 at 16:25

• added package setspace for vertical space around cells content in last two columns
• amsmath changed with mathtools, with its pmatrix* can be pmatrix columns right aligned

\documentclass{article}
\usepackage{mathtools, array, cellspace}% changed package, new package

\begin{document}
\begin{table}[hbt]
\setlength\cellspacetoplimit{3pt}    % add vertical space above cell content
\setlength\cellspacebottomlimit{3pt} % add vertical space below cell content
\renewcommand\arraystretch{1.3} % for a slightly more open look
\setlength\arraycolsep{3pt}     % for smaller distances between pmatrix columns
\centering
\begin{tabular}{|l|l|*{2}{>{$}Sc<{$}|}} % changed column types for last two columns
\cline{2-4}
\multicolumn{1}{l|}{} & \multicolumn{3}{c|}{Examples}\\
\cline{2-4}
\multicolumn{1}{l|}{} & Description &  M  &  \mathbf{u} \\
\hline
Translation & through vector $\begin{pmatrix}6\\7\end{pmatrix}$
&  \displaystyle\begin{pmatrix} 1 & 0 \\ 0 & 1 \end{pmatrix}
&  \begin{pmatrix}6\\7\end{pmatrix} \\
\hline
Reflection  & in line $x=2$
&  \begin{pmatrix*}[r] -1 & 0 \\ 0 & 1 \end{pmatrix*}
&  \begin{pmatrix}4\\0\end{pmatrix} \\
\hline
Rotation    & about $\mathbf{0}$ through $\pi$ radians
&  \begin{pmatrix*}[r] -1 & 0 \\ 0 & -1 \end{pmatrix*}% right align columns in pmatrix
&  \begin{pmatrix}0\\0\end{pmatrix} \\
\hline
Glide reflection & in line $y=x$, then through $\begin{pmatrix}1\\1\end{pmatrix}$
& \begin{pmatrix} 0 & 1 \\ 1 & 0 \end{pmatrix}
& \begin{pmatrix}1\\1\end{pmatrix} \\
\hline
\end{tabular}
\caption{Examples of Euclidean Transformations}
\label{tab1}
\end{table}
\end{document}


To improve the overall look of the table, you may also be interesred in booktabs package. No need for the vertical rules in this case. As you observe, the table now is less crappy due to the extra vertical space added by the package.

\documentclass{article}
\usepackage{amsmath,booktabs}
\begin{document}
\begin{table}[hbt]
\centering
\begin{tabular}{*4{l}}
\toprule
& \multicolumn{3}{c}{Examples}\\
\cmidrule{2-4}
& description & $M$ & \textbf{u}\\
\midrule translation & through vector $\begin{pmatrix}6\\7\end{pmatrix}$ & $\begin{pmatrix} 1 & 0 \\ 0 & 1 \end{pmatrix}$ & $\begin{pmatrix}6\\7\end{pmatrix}$\\
\midrule reflection & in line $x=2$ & $\begin{pmatrix} -1 & 0 \\ 0 & 1 \end{pmatrix}$ & $\begin{pmatrix}4\\0\end{pmatrix}$\\
\midrule rotation & about \textbf{0} through $\pi$ radians & $\begin{pmatrix} -1 & 0 \\ 0 & -1 \end{pmatrix}$ & $\begin{pmatrix}0\\0\end{pmatrix}$\\
\midrule glide reflection & in line $y=x$, then through $\begin{pmatrix}1\\1\end{pmatrix}$ & $\begin{pmatrix} 0 & 1 \\ 1 & 0 \end{pmatrix}$ & $\begin{pmatrix}1\\1\end{pmatrix}$\\
\bottomrule
\end{tabular}
\caption{Examples of Euclidean Transformations}
\label{tab1}
\end{table}
\end{document}


A possibly better version (by removing the inner \midrules and adding a small vertical height to the row by \\[8pt] as proposed by @Mico):

\begin{tabular}{*4{l}}
\toprule
& \multicolumn{3}{c}{Examples}\\
\cmidrule{2-4}
& description & $M$ &  $\mathbf{u}$\\
\midrule translation & through vector $\begin{pmatrix}6\\7\end{pmatrix}$ & $\begin{pmatrix} 1 & 0 \\ 0 & 1 \end{pmatrix}$ & $\begin{pmatrix}6\\7\end{pmatrix}$\\[8pt]
reflection & in line $x=2$ & $\begin{pmatrix} -1 & 0 \\ 0 & 1 \end{pmatrix}$ & $\begin{pmatrix}4\\0\end{pmatrix}$\\[8pt]
rotation & about \textbf{0} through $\pi$ radians & $\begin{pmatrix} -1 & 0 \\ 0 & -1 \end{pmatrix}$ & $\begin{pmatrix}0\\0\end{pmatrix}$\\[8pt]
glide reflection & in line $y=x$, then through $\begin{pmatrix}1\\1\end{pmatrix}$ & $\begin{pmatrix} 0 & 1 \\ 1 & 0 \end{pmatrix}$ & $\begin{pmatrix}1\\1\end{pmatrix}$\\
\bottomrule
\end{tabular}


• Possible improvements might be centering “description” (with \multicolumn{1}{c}{description} and columns 3 and 4. – egreg Dec 9 '16 at 18:09

You need to replace the header lines

\hline & \multicolumn{3}{c|}{Examples}\\
\cline{2-4}
& description & $M$ & \textbf{u}\\


with

\cline{2-4}
\multicolumn{1}{l|}{} & \multicolumn{3}{c|}{Examples}\\
\cline{2-4}
\multicolumn{1}{l|}{} & description & $M$ & $\mathbf{u}$\\


A full MWE:

\documentclass{article}
\usepackage{amsmath,array}
\begin{document}
\begin{table}[hbt]
\setlength\extrarowheight{2pt}  % for a slightly more open look
\centering
\begin{tabular}{|l|l|c|c|}
\cline{2-4}
\multicolumn{1}{l|}{} & \multicolumn{3}{c|}{Examples}\\
\cline{2-4}
\multicolumn{1}{l|}{} & Description & $M$ & $\mathbf{u}$\\
\hline
Translation & through vector $\begin{pmatrix}6\\7\end{pmatrix}$
& $\begin{pmatrix} 1 & 0 \\ 0 & 1 \end{pmatrix}$
& $\begin{pmatrix}6\\7\end{pmatrix}$\\
\hline
Reflection  & in line $x=2$
& $\begin{pmatrix} -1 & 0 \\ 0 & 1 \end{pmatrix}$
& $\begin{pmatrix}4\\0\end{pmatrix}$\\
\hline
Rotation    & about $\mathbf{0}$ through $\pi$ radians
& $\begin{pmatrix} -1 & 0 \\ 0 & -1 \end{pmatrix}$
& $\begin{pmatrix}0\\0\end{pmatrix}$\\
\hline
Glide reflection & in line $y=x$, then through $\begin{pmatrix}1\\1\end{pmatrix}$
& $\begin{pmatrix} 0 & 1 \\ 1 & 0 \end{pmatrix}$
& $\begin{pmatrix}1\\1\end{pmatrix}$\\
\hline
\end{tabular}
\caption{Examples of Euclidean Transformations}
\label{tab1}
\end{table}
\end{document}
`