FAQ vignettes for ggplot2

[mine-cetinkaya-rundel]

These were created based on an analysis of the most commonly asked questions about ggplot2 on SO. A summary of these can be found here (requires login).

A few notes:

• If using a package other than ggplot2 in the answers, I've indicated the package name with ::.
• There is a minimal amount of custom CSS on top fo the FAQ pages that ensure better spacing for readability.
• I think we should add alt text to the images but I'd like to do that after a round of review to avoid rewriting them.

There are some questions that were commonly asked that I didn't include. Happy to add these in if we think it would be good to do so (and I might ask for guidance on most elegant solutions for some).

• Questions not included because I'm not sure of the most elegant solution:
  • How can I set the background color of facet labels based on another variable?
  • How can I show the x and y axis on all panels in a faceted plot?
  • How can I place a legend for each facet?
  • How can I add floating axis labels in facet_wrap plot -- this seems to already work and, to me, placing them at the bottom doesn't look very good
• Questions that I wasn't sure which FAQ page to place in and didn't seem worth creating an individual page for
  • How can I use ggplot2 in a function -- I think this is well covered in the vignette on using ggplot2 in packages
  • How can I change the whisker definition in a box plot?
• Question I thought was out of scope but could easily add to barplots FAQ if we decide it's in scope:
  • How can I make an animated, racing bar plot?

[yutannihilation]

These packages need to be included in Suggests.

Error: Error: processing vignette 'faq-axes.Rmd' failed with diagnostics:

there is no package called 'ggtext'

Error: Error: processing vignette 'faq-bars.Rmd' failed with diagnostics:

there is no package called 'tidyr'

Error: Error: processing vignette 'faq-reordering.Rmd' failed with diagnostics:

there is no package called 'forcats'

[thomasp85]

I'm not sure we want them in Suggests, to be honest... @mine-cetinkaya-rundel is it imperative that this is a vignette that is distributed with thee package, or could it be an article on the ggplot2 site?

[mine-cetinkaya-rundel]

I think this is up to you -- also mainly why I left this as a draft PR for now, was going to discuss with @hadley as well and then flip the switch.

My thoughts:

• I think these will be most helpful for people googling such questions, so articles on ggplot2 site could be sufficient.
• If distributed with the package they might be helpful to those who are not always working online, and hence not able to google/SO things as easily. But I imagine this is not a large proportion of users.
• So I'm not sure of the burden of additional dependencies (even if in Suggests only) vs. the potential benefit of offline access.
• I tried to be selective in non ggplot2 packages I use -- they're either tidyverse or those that I think we can reasonably be confident will be kept in good shape.

Let me know if you have a preference one way or another and I'm happy to update as such. If going the article on site only route, I'd love a pointer on how we indicate that in the package (a link to another package that uses that would be sufficient).

[clauswilke]

I frequently find it helpful to put vignettes into the .Rbuildignore. In this way, they're in the github repo, they show up in the pkgdown site, but they're excluded from the R check and from CRAN. I think that's a good compromise. I would assume people are much more likely to look for documentation materials on the package website than on CRAN. (If I google "ggplot2" the first hit I get is ggplot2.tidyverse.org, so as long as the article is there I'd find it.)

[hadley]

Or you can use use_article() to put them in a subdirectory — we'd still need to declare these packages somewhere though, so that pkgdown can have them installed them.

[mine-cetinkaya-rundel]

I've made the FAQs into articles and added a Config/Needs/Website field to DESCRIPTION for the additional packages needed to build the articles

[thomasp85]

Thanks @mine-cetinkaya-rundel !