Ensure rank overlay plot starts at 0 even if not all bins present

[jgabry]

fixes #331

Code to test:

x <- posterior::as_draws_array(
  list(
    list(theta = -2 + 0.003 * 1:1000 + arima.sim(list(ar = 0.7), n = 1000, sd = 0.5)),
    list(theta = 1 + -0.01 * 1:1000 + arima.sim(list(ar = 0.7), n = 1000, sd = 0.5))
  )
)
bayesplot::mcmc_rank_overlay(x)

[jgabry]

There may be a more elegant solution, but this seems to get the job done

[sims1253]

Not sure if this is more elegant but an expand.grid with one left join and an if_else to fill the zeros should also work. Something like the following. Reads a little easier for me, though that might just be me. (not tested!)

all_combos <- tibble::as_tibble(expand.grid(
  parameter = unique(data$parameter),
  chain = unique(data$chain),
  bin_start = unique(histobins$bin_start),
  stringsAsFactors = FALSE
))

d_bin_counts <- all_combos %>%
  left_join(d_bin_counts, by = c("parameter", "chain", "bin_start")) %>%
  mutate(n = if_else(is.na(n), 0L, n))

[sims1253]

# Ensure all combinations exist and count values
d_bin_counts <- data %>%
  left_join(histobins, by = "value_rank") %>%
  count(.data$parameter, .data$chain, .data$bin_start) %>%
  right_join(
    dplyr::expand(.data$parameter, .data$chain, unique(histobins$bin_start)),
    by = c("parameter", "chain", "bin_start")
  ) %>%
  mutate(n = dplyr::coalesce(n, 0L))

Or courtesy of claude, telling me my solution was verbouse and not dplyr-ish enough.

[jgabry]

Thanks to you and Claude, both!

[jgabry]

dplyr::expand

Except Claude didn't realize there is no dplyr::expand . There is tidyr::expand, but we don't already depend on tidyr so probably best not to add another dependency just for this.

[sims1253]

Ha, great help :D

[jgabry]

The failure on macOS-latest (devel) is due to the vdiffr package failing to compile on GitHub actions

[sims1253]

Maybe add a set.seed to the test to make it deterministic?

[jgabry]

Maybe add a set.seed to the test to make it deterministic?

There's a set.seed in the file where I added the code to create the data for the test (it just doesn't show up in the diff since I didn't change it):

bayesplot/tests/testthat/data-for-mcmc-tests.R

Line 33 in 4147555

set.seed(11172017)

[jgabry]

@sims1253 Thanks. I just pushed a commit that uses basically your first suggestion of expand_grid plus a left_join.

[jgabry]

Going to merge since everything is passing except the unrelated failure on macos-latest (devel) that happens when installing the vdiffr dependency. Thanks again @sims1253.