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Errors

Errors can be reported either from the L^ATEX phase (in which case it is reported as such) or the lower level TEX phase. Don't be too put off by the half-digested text displayed. A line number is reported which usually helps to detect the error. Typing `h' sometimes produces helpful diagnostics. The most common errors reported are

• a command misspelt

• a mismatched brace

• improper use of special characters

• forgetting to have the appropriate \usepackage{...} lines.

• an error like this

  Overfull \hbox (15.42563pt too wide) in paragraph at lines 
  285--288 \OT1/ppl/m/n/10 You can cre-ate ver-tical space 
  between lines or ho-ri-zontal space   between
  

  means that lines 285 to 288 are producing a text line about 15 pts (about 5mm) too wide. \OT1/ppl/m/n/10 is the specification of the font used. When TEX does right and left alignment, it works out how much space it needs to leave between words and where to hypenate words if necessary. But the amount of space it's prepared to leave has to fall within a certain range and it will only split words in certain places (shown in the error message by a hyphen). If these restrictions mean that L^ATEX can't produce a satisfactory line, it will produce as much of the line as it can. A re-phrasing of the offending sentence will usually solve the problem. Another thing you might try is to control the way a troublesome word is hyphenated using something like

  \hypenation{furthermore fur-ther-more}
  

  at the top of your file. If all else fails, use {\sloppy...} to enclose the offending text.

• L^ATEX issues a *.

  This means L^ATEX needs more input. It probably means you've missed out an \end{document}, but if not you may be able to get L^ATEX to continue processing as best it can by typing <Return>.

• ! Argument of \label has an extra }

  If you're sure you haven't left out a left brace, then maybe you need to protect the inmost (fragile) command. For example, in some older versions of L^ATEX \label is fragile which causes a problem in sequences like
  \caption{Picture\label{margin}},
  so the safer construction
  \caption{Picture\protect\label{margin}}
  has to be used.

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© Cambridge University Engineering Dept
Information provided by Tim Love
2006-08-30