siunitx support

[pierrethibault]

It would be nice to have support for SI units. The LaTeX package siunitx has a mathjax version (https://github.com/mathjax/MathJax-third-party-extensions/tree/master/siunitx) so it looks like a good candidate.

[hplgit]

What kind of support do you have in mind? Can't you just include siunitx (through \usepackage{siunitx}) in latex output and apply the package for latex and html output?

[pierrethibault]

Then I am missing something. How can I ensure that, e.g., !bt \SI{1}{Pa} = \SI{1}{N/m^2} !et is rendered correctly with "doconce format html" ?

[pierrethibault]

Alright what I have figured out is that the section <script type="text/x-mathjax-config"> has to be modified to add the line:

MathJax.Ajax.config.path["Contrib"] = "https://cdn.mathjax.org/mathjax/contrib";

and with

"[Contrib]/siunitx/unpacked/siunitx.js"

in the extensions list. All I'd need is a recommendation on how to do this. Some kind of post-processing of the html file? Thanks.

[pierrethibault]

Alright. Not very elegant but adding this at the beginning of the document works:

# #if FORMAT in ("html")
<script type="text/x-mathjax-config">
MathJax.Ajax.config.path["Contrib"] = "https://cdn.mathjax.org/mathjax/contrib";
MathJax.Hub.Config({
  TeX: {
     equationNumbers: {  autoNumber: "AMS"  },
     extensions: ["AMSmath.js", "AMSsymbols.js", "autobold.js", "color.js", "[Contrib]/siunitx/unpacked/siunitx.js"]
  }
});
</script>
# #endif

And for latex, I used instead --latex_preamble to insert the \usepackage{siunitx}.

[hplgit]

OK, we could offer --units to get the latex and html versions. Any idea how it works with sphinx and ipynb?

[pierrethibault]

Apparently in both cases one has to insert this script somewhere:

<script type="text/x-mathjax-config">
MathJax.Ajax.config.path["Contrib"] = "https://cdn.mathjax.org/mathjax/contrib";
MathJax.Hub.Config({
  TeX: {
     equationNumbers: {  autoNumber: "AMS"  },
     extensions: ["AMSmath.js", "AMSsymbols.js", "autobold.js", "color.js", "[Contrib]/siunitx/unpacked/siunitx.js"]
  }
});
</script>

I don't know the best way to do it for sphinx. Maybe directly in a css file? (As in https://github.com/numerical-mooc/numerical-mooc/blob/master/styles/numericalmoocstyle.css).

For ipynb, one way to do it is to execute a cell with

from IPython.core.display import HTML
HTML(r"""
<script>
MathJax.Ajax.config.path["Contrib"] = "https://cdn.mathjax.org/mathjax/contrib";
MathJax.Hub.Config({
  TeX: {
     extensions: ["[Contrib]/siunitx/unpacked/siunitx.js"]
  }
});
</script>
""")

Ipython has an offline mathjax library, whereas this requires an internet connection. Also third-party extensions work only for mathjax versions >= 2.5.

[hplgit]

It seems to me that Sphinx hides MathJax options from the user so we are not able to adjust the settings. I do not think incorporating MathJax into css files is the way to go - it would require hacking all the css files for all Sphinx styles. Direct hacking of the .html files seems to be a better option.

So far, I have added a command-line argument --siunits that incorporates the siunitx package in latex and html/mathjax. Not sure if your special hack is better since it becomes a hack anyway...