title: ! Extra }, or forgotten \endgroup. latex
body: <p>hey, I met these latex format problem, anyone can offer some help?</p>
  
  <p>the .tex file:</p>
  
  <pre><code>  \begin{table}{}
    \renewcommand{\arraystretch}{1.1}
    \caption{Cambridge Flow feature definition and description}
    \label{cambridge-feature}}
    \centering
    \begin{tabular}{|c|c|}
    \hline\bfseries Abbreviation &amp;\bfseries Description\\
    \hline
    serv-port &amp; Server port\\
    \hline
    clnt-port &amp; Client port\\
    \hline
    push-pkts-serv &amp; count of all packets with\\ 
     &amp; push bit set in TCP header (server to client)\\
    \hline
    init-win-bytes-clnt &amp; the total number of bytes \\
    &amp; sent in initial window (client to server)\\
    \hline
    init-win-bytes-serv &amp; the total number of bytes sent\\
    &amp; in initial window (server to client)\\
    \hline
    avg-seg-size-clnt &amp; average segment size: \\
    &amp; data bytes devided by number of packets\\
    \hline
    IP-bytes-med-clnt &amp; median of total bytes in IP packet\\
    \hline
    act-data-pkt-serv &amp; count of packet with at least one byte \\
    &amp; of TCP data playload (server to client)\\
    \hline
    data-bytes-var-clnt &amp; variance of total \\
    &amp; bytes in packets (client to server)\\
    \hline
    min-seg-size-serv &amp; minimum segment size \\
    &amp; observed (server to client)\\
    \hline
    RTT-samples-serv &amp; total number of RTT samples\\
    &amp; found (server to client),\\
    &amp; {\bf see also \cite{Moore05discriminators}}\\
    \hline
    push-pkts-clnt &amp;  count of all packets with push bit set \\
    &amp; in TCP header (server to client)\\
    \hline
    \end{tabular}
    \end{table}
  </code></pre>
  
  <p>and the error message:</p>
  
  <pre><code>! Extra }, or forgotten \endgroup.
  \@endfloatbox ...pagefalse \outer@nobreak \egroup
  \color@endbox
  l.892 \end{table}
  </code></pre>
  
  <p>I've deleted a group-closing symbol because it seems to be
  spurious, as in <code>$x}$'. But perhaps the } is legitimate and
  you forgot something else, as in</code>\hbox{$x}'. In such cases
  the way to recover is to insert both the forgotten and the
  deleted material, e.g., by typing `I$}'.</p>
  
  <p>there is no $ in my table, also this { are matching with the }, and also after I comment the citation, the error remains.</p>
  
  <p>anyone can offer help?</p>
  
  <p>really appreciate all the comments!</p>
  
  <pre><code>! Extra }, or forgotten \endgroup.
  </code></pre>