[texhax] illegal parameter

[Barbara Beeton]

    I am confused about the error I am getting in the following.
    (I have commented out the file calls and the code which seems irrelevant to the problem.
    I defined the macro \ve to replace \vec, since the latter puts a tiny arrow above even a long expression.
    I presume this is the source of the problem, but I have used \ve millions of times with no such problem.)
    The error points to the caption line (near the end of the figure->center environment, six lines before the end of the code.

i haven't tested this, but i suspect the
problem may be the use of non-robust
commands in the caption.  try putting
\protect before each of them:

  \caption{$\protect\vu+(\protect\vv+\protect\vw)$(dashed)
    $=(\protect\vu+\protect\vv)+\protect\vw$ (dotted)}

you also might want to consider using
\centering rather than
\begin{center} ... \end{center} in the
figure, to avoid the extra vertical space
that the center environment adds.

good luck.
						-- bb
			--------------------

    %!TEX TS-program =  latex
    \documentclass[11pt]{article}
    [...]

    \newcommand{\ve}[1]{\ensuremath{\overrightarrow{#1}}}
    
    \newcommand{\vu}{\ve{u}}
    \newcommand{\vv}{\ve{v}}
    \newcommand{\vw}{\ve{w}}
    
    
    \begin{document}
    %a line before
    \thispagestyle{empty}
    \begin{figure}[htbp]
    \begin{center}
    [...]
    \caption{$\vu+(\vv+\vw)$(dashed) $=(\vu+\vv)+\vw$ (dotted)}
    \end{center}
    \end{figure}
    
    %a line after
    
    \end{document}
    
    The error I get is
    
    ./Briefpicturetest.tex:35: Illegal parameter number in definition of \reserved@
    a.
    <to be read again>
                       \crcr
    l.35 ...v+\vw)$(dashed) $=(\vu+\vv)+\vw$ (dotted)}
    
    
    
    ? ?
    
    
    Zbigniew Nitecki
    Department of Mathematics
    Tufts University
    Medford, MA 02155
    
    telephones:
    Office    (617)627-3843
    Dept.    (617)627-3234
    Dept. fax    (617)627-3966
    http://www.tufts.edu/~znitecki/