Bug: histogram silently ignores data, when bin size is too small

[cnowzohour]

I am creating very fine-grained histograms of timestamps and discovered that when the bin size is too small the plot just silently omits parts of the data. In the example below I create hourly timestamps for one day and then plot a histogram of bin size 10s. With this bin size only the hours 12am to 1pm get displayed. When increasing the bin size to 20s, all 25 timestamps are plotted.

I am using R 3.3.3 and plotly 4.6.0.

library(plotly)

bin.size.s <- 10

startPOSIX <- as.POSIXct("2017-05-12 00:00:00")
endPOSIX <- as.POSIXct("2017-05-13 00:00:00")
ts <- seq(as.numeric(startPOSIX, origin = "1970-01-01"), as.numeric(endPOSIX, origin = "1970-01-01"), by = 3600)

bins <- list(
  start = startPOSIX,
  end = endPOSIX,
  size = bin.size.s * 1000
)

print(
  plot_ly() %>%
    add_histogram(x = as.POSIXct(ts, origin = "1970-01-01"), autobinx = FALSE, xbins = bins)
)

[cpsievert]

Hmm, I see this with the most recent version 4.6.0.9000

Is that not what you expect?

[cnowzohour]

No: there are 25 timestamps in the dataset, but only 14 are displayed. You can check this by increasing bin.size.s to 20 or by hist(as.POSIXct(ts, origin = "1970-01-01"), breaks = "mins").

[cnowzohour]

I realized that this issue is not related to timestamps, but occurs generally when the bin size is too small. It seems to be an issue in plotly.js:

https://codepen.io/cnowzohour/pen/qmYmoM

vs

https://codepen.io/cnowzohour/pen/vmjmjM

I'll create an issue there.