Using fig.subcap and fig.align does not give expected result

[StephenGerry]

I am using fig.subcap to create sub-figures, which normally works really well. But when the figures do not fill the full width of the page I'd like to centre the combined image. However using fig.align='center' does not centre all of the subfigures properly.

Here is an example:

---
output:
  pdf_document:
    extra_dependencies: "subfig"
    keep_tex: true
---

```{r, fig.cap='Figure 1', fig.subcap=c('a','b','c'), fig.ncol=1, out.height='30%', fig.align='center'}

plot(1:10)
plot(cars, pch=19)
boxplot(Sepal.Width ~ Species, data=iris)

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[StephenGerry]

Apologies, these are the chunk options I used {r, fig.cap='Figure 1', fig.subcap=c('a','b','c'), fig.ncol=1, out.height='30%', fig.align='center'}

[cderv]

I can reproduce the issue. I guess the Latex code generated is not quite right for this usage.

Do you know how to produce such vertically centered aligned figure in Latex using \subfloat ? If so it could help us know what to do, otherwise I'll look into it.

[StephenGerry]

Thanks very much Christophe. I am no Latex expert I'm afraid! But this link (https://tex.stackexchange.com/questions/457917/subfloat-vertical-alignment) implies that the problem is something to do with using '\newline' between the subfloats. Replacing 'newline' with the double backslash in the tex file does indeed seem to work.