Master/texmf-doc/doc/english/FAQ-en/html/FAQ-altabcr.html


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<head>
<title>UK TeX FAQ -- question label altabcr</title>
</head><body>
<h3>Alignment tab changed to <code>\</code><code>cr</code></h3>
<p/>This is an error you may encounter in LaTeX when a tabular
environment is being processed.  &ldquo;Alignment tabs&rdquo; are the
<code>&amp;</code> signs that separate the columns of a tabular; so the error
message
<blockquote>

<pre>
! Extra alignment tab has been changed to \cr
</pre>
</blockquote><p>
could arise from a simple typo, such as:
<blockquote>
<pre>
\begin{tabular}{ll}
  hello   & there & jim \\
  goodbye & now
\end{tabular}
</pre>
</blockquote><p>
where the second <code>&amp;</code> in the first line of the table is more than the
two-column <code>ll</code> column specification can cope with. In this
case, an extra &ldquo;<code>l</code>&rdquo; in that solves the problem.  (If you
continue from the error in this case, &ldquo;<code>jim</code>&rdquo; will be moved
to a row of his own.)  Another simple typo that can provoke the error
is:
<blockquote>
<pre>
\begin{tabular}{ll}
  hello   & there
  goodbye & now
\end{tabular}
</pre>
</blockquote><p>
where the &lsquo;<code>\\</code>&rsquo; has been missed from the first line of the table.
In this case, if you continue from the error, you will find that
LaTeX has made a table equivalent to:
<blockquote>
<pre>
\begin{tabular}{ll}
  hello   & there goodbye\\
  now
\end{tabular}
</pre>
</blockquote><p>
(with the second line of the table having only one cell).
<p/>Rather more difficult to spot is the occurrence of the error when
you&rsquo;re using alignment instructions in a &ldquo;<code>p</code>&rdquo; column:
<blockquote>
<pre>
\usepackage{array}
...
\begin{tabular}{l&gt;{\raggedright}p{2in}}
here & we are again \\
happy & as can be
\end{tabular}
</pre>
</blockquote><p>
the problem here (as explained in 
<a href="FAQ-tabcellalign.html">tabular cell alignment</a>) is that the
<code>\</code><code>raggedright</code> command in the column specification has overwritten
<code>tabular</code>&rsquo;s definition of <code>\\</code>, so that
&ldquo;<code>happy</code>&rdquo; appears in a new line of the second column, and the
following <code>&amp;</code> appears to LaTeX just like the second
<code>&amp;</code> in the first example above.
<p/>Get rid of the error in the way described in 
<a href="FAQ-tabcellalign.html">tabular cell alignment</a> &mdash; either use
<code>\</code><code>tabularnewline</code> explicitly, or use the <code>\</code><code>RBS</code> trick described
there.
<dl>
<dt><tt><i>array.sty</i></tt><dd>Distributed as part of <a href="ftp://cam.ctan.org/tex-archive/macros/latex/required/tools.zip">macros/latex/required/tools</a> (<a href="ftp://cam.ctan.org/tex-archive/macros/latex/required/tools.tar.gz">gzipped tar</a>, <a href="http://www.tex.ac.uk/tex-archive/macros/latex/required/tools/">browse</a>)
</dl>
<p/><p>This question on the Web: <a href="http://www.tex.ac.uk/cgi-bin/texfaq2html?label=altabcr">http://www.tex.ac.uk/cgi-bin/texfaq2html?label=altabcr</a>
</body>