demo/ggplot2Example does not work

[travis-leith]

At least not with the latest version of ggplot2 (3.5.1)

Even the test in the demo fails

## create `data.table` with `idx` of type `nanotime`:
  idx <- nanotime(1) + 1e9*(1:100)
  dt <- data.table(idx=idx, a=1:100, b=11:110)
  
  ## nanotime on the x-axis:
  ggplot(dt, aes(x=idx, y=b)) +
    geom_line()

fails with

Error: Invalid input: nanotime_trans works with objects of class nanotime only

The failure happens at this check

 if (!inherits(x, "nanotime")) {
        stop("Invalid input: nanotime_trans works with objects of class ",
             "nanotime only", call. = FALSE)
      }

[travis-leith]

Is it worth making this functionality a core part of the package, and including official tests to prevent regression?

[travis-leith]

I can get this to work if I remove the type check and also remove anything to do with time zones.

[eddelbuettel]

Ack. scales and other things like preferred / default transformation names appear to have changed since this was written as ggplot2 tends to change for better or (here) worse.

This may just need to be withdrawn.

[eddelbuettel]

@lsilvest My memory is foggy but we seem to have taken this from your repo at lsilvest/nanotime_ggplot.

Have you by chance revisited 'scales' for ggplot2 for nanotime?

[eddelbuettel]

There is a micro-error in the demo file:

modified   demo/ggplot2Example.R
@@ -12,7 +12,7 @@ if (requireNamespace("ggplot2", quietly=TRUE) &&
 
     nanotime_format <- function(format = getOption("nanotimeFormat", default="%Y-%m-%dT%H:%M:%EXS%Ez"),
                                 tz     = getOption("nanotimeTz", default="UTC")) {
-        function(x) format(x, format, tz=tz)
+        function(x) format(x, format, tz)
     }
 

but even with that fixed, and running under Ubuntu 20.04 "focal" as a test (to get an older ggplot2) I get an error:

Error in validate_guide(guide) : Unknown guide

I think it may be best to just quietly retire this demo file. One can plot with nanotime by running as.POSIXct() over the column first.

[travis-leith]

On one hand I think retiring it would be a shame, but on the other hand, this package isn't really about supporting visualisations from other packages so makes sense to retire.

[lsilvest]

Yes, I imagine there's been some changes in ggplot2... Before we decide to retire it, I'll take a stab at it and see if we can fix this.

[eddelbuettel]

We are coming up to a new CRAN release and I plan to skip shipping the example file there. It needs a bigger update, and maybe these days there are other ggplot2 helper packages for scale manipulation that we can lean on. Another time.