annotate("segment", ...) doesn't work with dates on x-axis

[vkryukov]

How to reproduce:

library(data.table)
library(lubridate)
library(ggplot2)

# Prepare some random data
set.seed(1234)
dt <- data.table(x = rnorm(365*5), d = seq(ymd(20130101), ymd(20131231), by = 86400))
dt.m <- dt[, list(total = sum(x)), by = list(month = floor_date(d, "month"))]
# Create a basic scatterplot chart
p <- qplot(month, total, data = dt.m)

This works:

# Both of these work as expected and produce the same result
p + geom_segment(x = as.numeric(ymd(20130401)), xend = as.numeric(ymd(20130701)), 
  y = -10, yend = 10)
p + geom_segment(aes(x = ymd(20130401), xend = ymd(20130701), 
  y = -10, yend = 10))

but this doesn't:

> p + annotate("segment", x = as.numeric(ymd(20130401)), xend = as.numeric(ymd(20130701)), 
  y = -10, yend = 10)
Error: Invalid input: time_trans works with objects of class POSIXct only

> p + annotate("segment", x = ymd(20130401), xend = ymd(20130701), 
  y = -10, yend = 10)
Error in Ops.POSIXt((x - from[1]), diff(from)) : 
  '/' not defined for "POSIXt" objects 

> p + annotate("segment", aes(x = ymd(20130401), xend = ymd(20130701), 
  y = -10, yend = 10))
Error in as.data.frame.default(x[[i]], optional = TRUE, stringsAsFactors = stringsAsFactors) : 
  cannot coerce class ""uneval"" to a data.frame

I have also posted a question to SO - there may be some additional details there. http://stackoverflow.com/questions/18796386/how-to-use-ggplot2s-annotate-with-dates-in-x-axis

[BrianDiggs]

A simplified test case which eliminates the dependence on data.table and lubridate (just to make sure that neither is the source of the problem):

dt <- 
structure(list(month = structure(c(1356998400, 1359676800, 1362096000, 
1364774400, 1367366400, 1370044800, 1372636800, 1375315200, 1377993600, 
1380585600, 1383264000, 1385856000), tzone = "UTC", class = c("POSIXct", 
"POSIXt")), total = c(-5.4586134857604, -13.7043187714622, 3.25254944094792, 
-10.3260511491301, 6.44178978776937, 2.46127352381964, -1.98673390397442, 
-16.3227453308624, 11.7148615457185, -2.23934628094151, 5.5084335509504, 
-10.7700077344507)), row.names = c(NA, -12L), class = "data.frame", .Names = c("month", 
"total"))

p <- qplot(month, total, data = dt)

p + geom_segment(x = as.numeric(as.POSIXct("2013-04-01")),
                 xend = as.numeric(as.POSIXct("2013-07-01")),
                 y = -10,
                 yend = 10)

p + geom_segment(aes(x = as.POSIXct("2013-04-01"),
                     xend = as.POSIXct("2013-07-01"),
                     y = -10,
                     yend = 10))

p + annotate("segment",
             x = as.numeric(as.POSIXct("2013-04-01")),
             xend = as.numeric(as.POSIXct("2013-07-01")),
             y = -10,
             yend = 10)
# Error: Invalid input: time_trans works with objects of class POSIXct only

p + annotate("segment",
             x = as.POSIXct("2013-04-01"),
             xend = as.POSIXct("2013-07-01"),
             y = -10,
             yend = 10)
# Error in Ops.POSIXt((x - from[1]), diff(from)) : 
#   '/' not defined for "POSIXt" objects

I did not include the version with annotate and aes because that is not how `annotate is meant to be called, so an error there is not surprising.

[hadley]

This sounds like a great feature/horrible bug, but unfortunately we don't currently have the development bandwidth to support it/fix it. If you'd like to submit a pull request that implements this feature/fixes this bug, please follow the instructions in the development vignette.

Tried to install the latest development version from github install_github("hadley/ggplot2"), but this problem still persists.

[BrianDiggs]

The patch for this was resubmitted as #950, but that has not been merged into the master branch yet.