Script to automate externalizing tikz graphics

Question

Is there a script to automate externalizing tikz graphics?

(As suggested by Scott here)

Answer 1

One answer to this question is "the developers are working on it".

The externalization method present in PGF/TikZ 2.00 works well if you need to pull a handfull of figures out of a document. However, it is a drag when it comes to automatically exporting all of the figures into external files.

This limitation has been known for some time and a new TikZ library, external, has been created to address this issue. The problem is, this new library is only present in the development builds of PGF and PGF has a very, very long development cycle (it has been two years since the last release).

Development versions can be obtained from the project's SourceForge site, but requires checking the code out using CVS- which is about as fun as ramming a flaming stick into your eyeball. Fortunately, the guys over at texample provide relatively up-to-date builds of the development code which are packaged in ready-to-use TDS-compliant zip files.

Using the development version of PGF, externalizing all TikZ graphics in a LaTeX document is as easy as:

\usetikzlibrary{external}
\tikzexternalize

If your document is named report.tex, this will dump out a series of images: report-figure0.pdf, report-figure1.pdf, etc, etc. To get a more manageable output, you can specify a directory for in which the files are to be placed and names that are more descriptive than report-figure0.pdf:

\usetikzlibrary{external}
\tikzexternalize[prefix=figures/]

% Rest of preamble
% Begin document, write stuff

% Set a filename for the next tikzpicture.
\tikzsetnextfilename{importantFigure}
\begin{tikzpicture}  % This will be output to figures/importantFigure.pdf
  % Picture code
\end{tikzpicture}

To compile the document, you will need to ensure the figures directory exists and run pdflatex with shell execution enabled:

mkdir figures
pdflatex -shell-escape <tex file>

A whole pile of options is available to customize the way the figures are output. See section 31.4 (this numbering is subject to change!) of the development version documentation for complete info and options. The manual also covers how to obtain EPS output- but this option looks less polished than PDF output.

Answer 2

I’ve just come up with the following. It seems to work quite well (on Unix/Linux and Mac):

SOURCE=$1
for name in $( \
    grep '^[:space:]*\\beginpgfgraphicnamed' $SOURCE | \
    sed s'/[:space:]*\\beginpgfgraphicnamed{\(.*\)}/\1/' \
); do
    pdflatex --jobname=$name $SOURCE
done

An explanation:

It uses grep to filter out all lines that contain \beginpgfgraphicsnamed, but only if there’s only whitespace before the command in the line. This prevents that commented-out commands are also found.

Next, it invokes sed to filter from those lines only the relevant part, i.e. the command argument that’s to be used as the pdflatex jobname. It then uses for to iterate over all these jobnames and calls pdflatex in turn for each of them.

Answer 3

Here's my alternative; Konrad's answer is probably just as good, and certainly better documented.

for job in `grep -o beginpgfgraphicnamed\{[0-9A-Za-z-]*\} < $1 | sed -e 's/beginpgfgraphicnamed{//' | sed -e 's/}//'`; do
    pdflatex --jobname $job $1;
    rm $job.log;
    rm $job.out;
    rm $job.aux;
done

Answer 4

When I was writing my MSc thesis, I had created all of my figures and diagrams with tikz and pgfplots (using matplotlib2tikz). Keeping all of them within the source was not acceptable, since the compilation time was getting really slow, so I was searching for something that would allow me to automatically compile all those figures to pdf files that I could include in my text.

For various reasons, I was not entirely satisfied with any of the other solutions so I wrote a Python script that suited my purpose.

The things you must keep in mind are:

1. You put the script on the same level as your main.tex file
2. You write your tikz code. You place each figure within a file with extension *.tikz. Each file contains only \begin{tikzpicture} ... \end{tikzpicture}.
3. You write the preamble that you want to use with the *.tikz files. This doesn't necessarily contains the same packages as the preamble of your main.tex file.
4. You run the script!

The script searches recursively within a folder structure for *.tikz files and compiles them using the specified preamble. Each time the scripts runs, it stores the modification time of each *.tikz file and on subsequent runs it compiles only the newly created files of the files that have been modified since the last run. If you make changes in your preamble, you just pass a command-line argument and it compiles all the *.tikz files.

On linux it works great. I haven't tested it on windows, but I don't see why it shouldn't run. Anyway, even if there is any problem, the fix is going to be really trivial