How do I combine twenty-seven sub-figures with captions?

[bergsmat]

Description

I'm using Quarto 1.6.39 with RStudio 2024.12.0 and R 4.4.2.

I created an instance of the quarto book template. In intro.qmd I appended this:

::: {#fig-1 layout-ncol=1}

![a](cover.png){#fig-1a}

![b](cover.png){#fig-1b}

![c](cover.png){#fig-1c}

<!-- and so on ... -->

![x](cover.png){#fig-1x}

![y](cover.png){#fig-1y}

![z](cover.png){#fig-1z}

![aa](cover.png){#fig-1aa}

This is figure 1.
:::

Then I executed quarto render at the terminal prompt.

In the html, I get 27 figures with captions (a) a through (z) z plus ({) aa. For pdf, I get LaTeX Error: Counter too large. I agree: 26 sub-figures should suffice for most cases, but I do have an actual use case with more.

[mcanouil]

Change the sub-reference labels: https://quarto.org/docs/authoring/cross-reference-options.html#numbering (edit: the issue is independent of the counter display value)

Edit: it seems to be a LaTeX limitation which you can lift with some pure LaTeX tweak via include-in-header or modifying the partials/templates.
The answer is on the internet (I did not investigate or try what LaTeX code works or not because it's really LaTeX specific and not much related to Quarto itself).
You can use keep-tex: true to investigate the LaTeX code and find the LaTeX workaround required for your use case.

Below a fully reproducible example for html.

Input

Output

Code --- title: "Reproducible Quarto Document" format: html engine: markdown crossref: subref-labels: roman --- ::: {#fig-placeholder layout-ncol="6"} {#fig-01} {#fig-02} {#fig-03} {#fig-04} {#fig-05} {#fig-06} {#fig-07} {#fig-08} {#fig-09} {#fig-10} {#fig-11} {#fig-12} {#fig-13} {#fig-14} {#fig-15} {#fig-16} {#fig-17} {#fig-18} {#fig-19} {#fig-20} {#fig-21} {#fig-22} {#fig-23} {#fig-24} {#fig-25} {#fig-26} {#fig-27} {#fig-28} {#fig-29} {#fig-30} A Caption :::

[mcanouil]

FWIW, Typst has a better counter system, using the same code as above minus the labels change:

[bergsmat]

@mcanouil Thanks, I didn't realize I could specify the numbering system. As you say, doing so does not rescue pdf. Typst looks intriguing, but not available for Quarto book. I will find a workaround for pdf. The one you cited looks promising.