[Tex/LaTex] Is there really something wrong with using the caption package for \ContinuedFloat

captionsdocument-classestemplateswarnings

In my question How to create an unnumbered algorithm with a caption?, a nice solution was suggested using \ContinuedFloat, from the caption package. However, when I use it, I get:

Package caption Warning: Unsupported document class (or package) detected,
(caption)                usage of the caption package is not recommended.
See the caption package documentation for explanation.

The package documentation says:

Please note: Many document classes already have built-in options and commands for customizing captions. If these possibilities are sufficient for you, there is usually no need for you to use the caption package at all. And if you are just interested in using the command \captionof, loading of the very small 'capt-of' package is usually sufficient.

but that's not what I'm after. I'm using a document class I've created as a (thin) wrapper based on report; I don't provide any built-ins I can use instead of \ContinuedFloat, and neither does report, as far as I can tell.

Is the use of caption really not recommended with the report class?
If so, why and what should I do about it?
If not, how can I 'tell' the package that mine is an 'ok class' to load with?

Best Answer

Perhaps not an answer, but it was too long to make it a comment. The documentation of the caption package says:

If you don’t find the document class you use in this section, you usually don’t have to worry: Many document classes (e.g. the octavo class) are derived from one of the standard document classes article, report, or book, and behave the same regarding captions. The caption package automatically does a compatibility check against the document class used and will give you the clear warning
Package caption Warning: Unsupported document class (or package)
detected, (caption) usage of the caption package is not recommended.
See the caption package documentation for explanation.
if such an incompatibility was detected. If you don’t get such warning everything is fine, but if you get it the usage of the caption package is not recommended and especially not supported.

If you get such a compatibility warning but decide to use the caption package anyway, you should watch carefully what side-effects occur, usually the look and feel of your captions will change by just including the caption package without options, meaning they do not look like as intended by the author of the document class. If this is fine for you, you should first specify the option style=base via \usepackage[style=base]{caption} or \captionsetup{style=base} to set the caption package into a well-defined state. Afterwards you can start setting your own options additionally and keep your fingers crossed.

Also, according to the documentation, the supported document classes are:

Standard LaTeX: book, report, article
AMS: amsart, amsproc, amsbook
beamer
KOMA-Script: scrreprt, scrartcl, scrbook
NTG: artikel, rapport, boek
SMF: smafart, smfbook
thesis

So, there's no problem using caption with the standard report document class. Since you are using a derived document class, you should pay attention to the last paragraph of the quote at the beginning of this message.

Related Solutions

[Tex/LaTex] Subcaption package: compatibility issue

The very recent version of the subcaption package will even issue an error:

! Package caption Error: The `subcaption' package does not work correctly
(caption)                in compatibility mode.

The only way to get around this is to specify the option compatibility=false to the caption package:

\documentclass{cifa}

\usepackage{subcaption}
\captionsetup{compatibility=false}

\begin{document}
\begin{figure}
\parbox{4cm}{\subcaption{This is a subcaption}\label{sub}}
\caption{nothing}
\label{nothing}
\end{figure}

See figure \ref{nothing}: there is \ref{sub} inside...

\end{document}

PLEASE NOTE: This way the customization of the captions done by the cifa document class will be overwritten by the caption package in a brute-force manner. In best case the output of the captions will look different (and some caption-related stuff offered by the cifa document class will not work anymore), in worst case you'll get error messages and weird output. So please also take a look at the caption package documentation, section "6 Package Support". Since this is a perfect method to shoot oneself in the foot, an extra warning is always issued when using the compatibility=false option:

Package caption Warning: Forced redefinition of \caption since the
(caption)                unsupported(!) package option `compatibility=false'
(caption)                was given.
See the caption package documentation for explanation.

If you do not want this (or it does not work anyway) then the only solution left is not-using the subcaption package. Use the subfig package with option caption=false (which prevents loading of the caption package) instead:

\documentclass{cifa}

\usepackage[caption=false]{subfig}

\begin{document}
\begin{figure}
\subfloat[This is a subcaption\label{sub}]{............}
\caption{nothing}
\label{nothing}
\end{figure}

See figure \ref{nothing}: there is \ref{sub} inside...

\end{document}

[Tex/LaTex] Remove colon in the caption of a figure without using caption package

A preliminary remark: If a journal you're submitting an article to requires you to use the elsarticle document class, it may be a poor idea to modify the caption style defined by the class. Your journal's style guidelines probably also state something to the effect that every float should have a (nonempty) caption, in which case some kind of separator (such as a colon) between the float's number and caption is generally needed.

Here's the definition of the \@makecaption command contained in the file elsarticle.cls

\long\def\@makecaption#1#2{%
  \vskip\abovecaptionskip\footnotesize
  \sbox\@tempboxa{#1: #2}%
  \ifdim \wd\@tempboxa >\hsize
    #1: #2\par
  \else
    \global \@minipagefalse
    \hb@xt@\hsize{\hfil\box\@tempboxa\hfil}%
  \fi
  \vskip\belowcaptionskip}

The two arguments of the \@makecaption macro are [Float] <num> and the caption's text, respectively. [Float] can be "Figure", "Table", or the name of any other floating environment recognized by LaTeX.

There are two ways to suppress the insertion of a colon following the float's name and number.

Method 1 : Remove the colon globally because the mandatory arguments (the stuff inside curly braces) of all \caption commands will always be empty. To achieve this, you could load the etoolbox package and issue the following commands:

\makeatletter
\patchcmd{\@makecaption}{#1: #2}{#1}{}{}
\makeatother

Method 2: Remove the colon whenever (and only if) the mandatory argument of the \caption command is empty. In this case, you may want to employ the following redefinition of the \@makecaption command:

\makeatletter
\long\def\@makecaption#1#2{%       
\vskip\abovecaptionskip\footnotesize
\sbox\@tempboxa{#2}         % place contents of #2 into a scratch TeX box
\ifdim \wd\@tempboxa = 0pt  % test if scratch box has zero width
   \centering #1 \par       % if yes, typeset only #1 (the float's name and number)
\else                       % if no, proceed with default definition
   \sbox\@tempboxa{#1: #2}%
   \ifdim \wd\@tempboxa >\hsize
     #1: #2\par
   \else
     \global \@minipagefalse
     \hb@xt@\hsize{\hfil\box\@tempboxa\hfil}%
   \fi
\fi
\vskip\belowcaptionskip}
\makeatother

Best Answer

Related Solutions

[Tex/LaTex] Subcaption package: compatibility issue

[Tex/LaTex] Remove colon in the caption of a figure without using caption package

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