Trouble with tables; can't find the missing $

Question

So I have made a table in LaTeX, containing certain values of an angle theta and a radius r. Of course, somewhere I'm missing a $. I have used the table generator from the website http://www.tablesgenerator.com/; this is the code

\begin{table}[]
\centering
\caption{My caption}
\label{my-label}
\begin{tabular}{llllllllllllll}
\theta & 0 & $\frac{\pi}{9}$ & $\frac{\pi}{6}$      & $\frac{2\pi}{9}$     & $\frac{\pi}{3}$ & $\frac{4\pi}{9}$     & $\frac{\pi}{2}$      & $\frac{5\pi}{9}$ & $\frac{2\pi}{3}$ & $\frac{7\pi}{9}$ & $\frac{5\pi}{6}$                           & $\frac{8\pi}{9}$                           & $\pi$ \\ \cline{13-13}
r      & 0 & $\frac{1}{2}$   & $\frac{\sqrt{2}}{2}$ & $\frac{\sqrt{3}}{2}$ & 1               & $\frac\{sqrt{3}}{2}$ & $\frac{\sqrt{2}}{2}$ & $\frac{1}{2}$    & 0                & $\frac{-1}{2}$   & \multicolumn{1}{l|}{$-\frac{\sqrt{2}}{2}$} & \multicolumn{1}{l|}{$\frac{-\sqrt{3}}{2}$} & -1    \\ \cline{13-13}
\end{tabular}
\end{table}

I've looked at it for hours and think I'm starting to go crazy.
Anyone wanna be crazy with me and spot what's missing?

Answer 1

Three suggestions:

• Use an array environment instead of a tabular environment. array environments are designed to contain primarily math-mode material. Making the switch will allow you do get rid of 42 [!] $ signs, significantly de-cluttering the code.

• Use an \fbox instruction to encase the second-to-last entry in the second row in rectangular gridlines. Don't use two \cline directives and two \multicolumn{1}{}{} "wrappers".

• \frac\{sqrt{3}}{2} must throw a syntax error. Presumably, it should be \frac{\sqrt{3}}{2}.

\documentclass{article}
\begin{document}
\begin{table}
\setlength\fboxsep{1pt} % default value: 3pt
\centering
\caption{My caption}
\label{my-label}
$\begin{array}{@{}*{14}{c}@{}}
\theta & 0 & \frac{\pi}{9} & \frac{\pi}{6} & \frac{2\pi}{9} 
& \frac{\pi}{3} & \frac{4\pi}{9} & \frac{\pi}{2} & \frac{5\pi}{9} 
& \frac{2\pi}{3} & \frac{7\pi}{9} & \frac{5\pi}{6} & \frac{8\pi}{9} 
& \pi \\[1ex] 
r & 0 & \frac{1}{2} & \frac{\sqrt{2}}{2} & \frac{\sqrt{3}}{2} & 1 
& \frac{\sqrt{3}}{2} & \frac{\sqrt{2}}{2} & \frac{1}{2} & 0 & \frac{-1}{2} 
& \frac{-\sqrt{2}}{2} & \fbox{$\frac{-\sqrt{3}}{2}$} & -1 \\ 
\end{array}$
\end{table}
\end{document}