Generating a separate pdf file of tables and figures from a latex file?

Question

Is it possible to generate a PDF of figures and tables of a paper from LaTeX itself?

I saw Journals and Conferences asking for a separate file of tables and figures.

In this question, questioner proposed a method that uses \usepackage{endfloat} to push all the figures and tables to the last pages and then use a PDF editor to cut the last pages of PDF. This is a solution but not a good one. LaTeX should be able to do this by its own.

What I have in mind is to compile the LaTeX file and it generates a complete PDF output and beside that a separate file that contains all the figures and tables of former PDF.

Answer 1

The following code will extract all graphics and floats. To prove it, I load the extracted objects again with \includepdf (see the animation).

% this file name is extractor.tex
% compile it with pdflatex -shell-escape extractor
\documentclass{article}

\usepackage{filecontents}
\begin{filecontents*}{template.tex}
\documentclass{article}
\usepackage{lipsum}
\usepackage{graphicx}
\usepackage{mwe}
\usepackage[active,tightpage,\placeholder]{preview}
%\PreviewEnvironment{\placeholder}
\PreviewBorder=12pt\relax


\begin{document}


\lipsum[1]

\begin{table}[htb]
\centering
\begin{tabular}{|lll|}
\hline
    11 & 12 & 13\\
    21 & 22 & 23\\
    31 & 32 & 33\\
    41 & 42 & 43\\
    51 & 52 & 53\\
\hline
\end{tabular}
\caption{A table}
\end{table}


\begin{figure}[htp]
\includegraphics{example-image-a}
\caption{A}\label{a}
\end{figure}

\lipsum[6-10]

\begin{figure}[htp]
\includegraphics{example-image-b}
\caption{A}\label{a}
\end{figure}

\begin{figure}[htp]
\includegraphics{example-image-c}
\caption{A}\label{a}
\end{figure}

\lipsum[16-20]


\end{document}
\end{filecontents*}

\usepackage{pgffor,pdfpages}

\begin{document}

\foreach \x in{graphics,floats}{%
    \immediate\write18{pdflatex -jobname=template-\x\space "\def\noexpand\placeholder{\x} \noexpand\input{template}"}%
    \includepdf[pages=-]{template-\x}%
}

\end{document}

The code above just simulates your scenario. To apply it in your real scenario, do the following.

Step 1

Assume that your input file is as follows.

\documentclass{article}
\usepackage{lipsum}
\usepackage{graphicx}
\usepackage{mwe}

\begin{document}

\lipsum[1]

\begin{table}[htb]
\centering
\begin{tabular}{|lll|}
\hline
    11 & 12 & 13\\
    21 & 22 & 23\\
    31 & 32 & 33\\
    41 & 42 & 43\\
    51 & 52 & 53\\
\hline
\end{tabular}
\caption{A table}
\end{table}

\begin{figure}[htp]
\includegraphics{example-image-a}
\caption{A}\label{a}
\end{figure}

\lipsum[6-10]

\begin{figure}[htp]
\includegraphics{example-image-b}
\caption{A}\label{a}
\end{figure}

\begin{figure}[htp]
\includegraphics{example-image-c}
\caption{A}\label{a}
\end{figure}

\lipsum[16-20]

\end{document}

Step 2

Insert

\usepackage[active,tightpage,graphics]{preview}
\PreviewBorder=12pt\relax

in your input file. So your input file becomes as follows.

\documentclass{article}
\usepackage{lipsum}
\usepackage{graphicx}
\usepackage{mwe}
\usepackage[active,tightpage,graphics]{preview}
\PreviewBorder=12pt\relax

\begin{document}

\lipsum[1]

\begin{table}[htb]
\centering
\begin{tabular}{|lll|}
\hline
    11 & 12 & 13\\
    21 & 22 & 23\\
    31 & 32 & 33\\
    41 & 42 & 43\\
    51 & 52 & 53\\
\hline
\end{tabular}
\caption{A table}
\end{table}

\begin{figure}[htp]
\includegraphics{example-image-a}
\caption{A}\label{a}
\end{figure}

\lipsum[6-10]

\begin{figure}[htp]
\includegraphics{example-image-b}
\caption{A}\label{a}
\end{figure}

\begin{figure}[htp]
\includegraphics{example-image-c}
\caption{A}\label{a}
\end{figure}

\lipsum[16-20]

\end{document}

Save this input file as anyfilename-graphics.tex

Step 3

Invoke pdflatex anyfilename-graphics to obtain a PDF file containing all extracted graphics.

Step 4

Repeat Step 2 but replace graphics with floats, save the file as anyfilename-floats.tex. Now compile with pdflatex anyfilename-floats to get a PDF file containing all extracted floats (figure or table).

Step 5

Done!

Answer 2

Everything between \begin{Export}{<type>} and \end{Export} is written into an external file with name \jobname-<type>#.tex. This one is run from within the document and the created pdf is then used by \includegraphics. The <type> parameter is not really important, it simplifies only the handling if there are a lot of tabulars and/or figures. This example creates the external files

test.tex         the main document
test-tab1.tex
test-tab1.pdf
test-tab2.tex
test-tab2.pdf
test-fig1.tex
test-fig1.pdf

and, of course, the .log and .aux files, too. The command \newcommand\WritePreamble{... must be extended if you need other or more packages for your tabulars and figures.

\documentclass{article}
\usepackage{fancyvrb}
\usepackage{graphicx}

\newcounter{extern}
\makeatletter
\renewcommand\FVB@VerbatimOut[1]{%
\@bsphack%
\begingroup
\FV@UseKeyValues%
\FV@DefineWhiteSpace%
\def\FV@Space{\space}%
\FV@DefineTabOut%
\def\FV@ProcessLine##1{%
\toks@{##1}\immediate\write\FV@OutFile{\the\toks@}}%
\immediate\openout\FV@OutFile #1\relax%
\WritePreamble%<<=== write preamble
\let\FV@FontScanPrep\relax
\let\@noligs\relax%
\FV@Scan}
\renewcommand\FVE@VerbatimOut{%<<=== write postamble
\WriteLine{\string\end{document}}% <<
\immediate\closeout\FV@OutFile\endgroup\@esphack}

\newcommand\WriteLine[1]{%
\begingroup%
\let\protect\@unexpandable@protect%
\edef\reserved@a{\immediate\write\FV@OutFile{#1}}%
\reserved@a%
\endgroup}
\makeatother

\newcommand\WritePreamble{%
\WriteLine{\string\documentclass[border=0pt]{standalone}}%
\WriteLine{\string\usepackage{array}}%
\WriteLine{\string\begin{document}}%
}

\newcommand\Export[1]{%
\stepcounter{extern}%
\gdef\externExt{#1}%
\VerbatimEnvironment%
\begin{VerbatimOut}{\jobname-#1\theextern.tex}}

\def\endExport{%
\end{VerbatimOut}
\IfFileExists{\jobname-\externExt\theextern.tex}
  {\typeout{>>>running pdflatex with file \jobname-\externExt\theextern.tex}%
   \immediate\write18{pdflatex --interaction=nonstopmode \jobname-\externExt\theextern}}
  {\fbox{Error in Export!}}%
\IfFileExists{\jobname-\externExt\theextern.pdf}
    {\includegraphics{\jobname-\externExt\theextern}}
    {\fbox{Error in running \jobname-\externExt\theextern.tex~ Try again}}%
}

\begin{document}

foo

\begin{Export}{tab}
\begin{tabular}{ccc}\hline
foo & bar & baz \\\hline
f   & b   & b   \\\hline
\end{tabular}
\end{Export}

bar

\begin{Export}{fig}
\setlength\unitlength{1cm}
\begin{picture}(3,3)
\put(1.5,1.5){\circle*{1}}
\end{picture}
\end{Export}

\begin{table}[!htb]
\centering
\caption{A caption of a tabular}
\begin{Export}{tab}
\begin{tabular}{ccc}\hline
f   & b   & b   \\\hline
foo & bar & baz \\\hline
\end{tabular}
\end{Export}
\end{table}

\end{document}

Answer 3

For little documents (articles or so) with all the figures and tables as floats, one possibility is to fix the rules for floats so that these rules cannot be accomplished. For example:

\renewcommand{\textfraction}{1.1} % that is 110% (too much)
\renewcommand{\floatpagefraction}{1}

So all the floats must move to the end of text. To return to floats placed within the text, simply comment these two lines.

A MWE to test that this approach could work:

\documentclass{article}
\usepackage{lipsum}
\usepackage{graphicx}
\usepackage{mwe}
\title{A MWE}
\author{Fran}
\renewcommand{\textfraction}{1.1}
\renewcommand{\floatpagefraction}{1}
\begin{document}
\maketitle

\lipsum[1]

\begin{table}[htb]
\centering
\begin{tabular}{|lll|}
\hline
    11 & 12 & 13\\
    21 & 22 & 23\\
    31 & 32 & 33\\
    41 & 42 & 43\\
    51 & 52 & 53\\
\hline
\end{tabular}
\caption{A table}
\end{table}


\begin{figure}[htp]
\includegraphics{example-image-a}
\caption{A}\label{a}
\end{figure}

\lipsum[6-10]

\begin{figure}[htp]
\includegraphics{example-image-b}
\caption{A}\label{a}
\end{figure}

\begin{figure}[htp]
\includegraphics{example-image-c}
\caption{A}\label{a}
\end{figure}

\lipsum[16-20]

% Table and figures come here 

\renewcommand{\textfraction}{1.1}
\renewcommand{\floatpagefraction}{1}

\end{document}

However, this surely will fail in big documents with many floats (typical "Too many unprocessed floats" error).