Insert ticks for days with labels for weeks

Question

In the following graph, I would like to insert ticks for days on x axis (date). There is an answer to x axis as continuous Adding minor tick marks to the x axis in ggplot2 (with no labels), but my x axis is date. As you can see, I have tried date_minor_breaks = "1 day" but unsuccessful. Any suggestions would be appreciated.

df<-structure(list(date = structure(c(1579132800, 1579219200, 1579305600, 
                                   1579392000, 1579478400, 1579564800, 1579651200, 1579737600, 1579824000, 
                                   1579910400, 1579996800, 1580083200, 1580169600, 1580256000, 1580342400, 
                                   1580428800, 1580515200, 1580601600, 1580688000, 1580774400, 1580860800, 
                                   1580947200, 1581033600, 1581120000, 1581206400, 1581292800, 1581379200, 
                                   1581465600, 1581552000, 1581638400, 1581724800, 1581811200, 1581897600, 
                                   1581984000, 1582070400, 1582156800, 1582243200, 1582329600, 1582416000), 
                                   class = c("POSIXct", "POSIXt"), tzone = "UTC"),cured = c(0, 0, 0, 0, 0, 0, 3, 3, 6, 7, 7, 13, 26, 34, 55, 
          77, 113, 180, 236, 372, 520, 723, 935, 1210, 1486, 1774, 
          2101, 2605, 2806, 3322, 3796, 4205, 4683, 5248, 5820, 6478, 
          7102, 7589, 7996)), 
row.names = c(NA, -39L), class = "data.frame")

library(ggplot2)
df %>% 
  mutate(
    x_date = as.Date(date)
  ) %>% 
  ggplot(aes(x = x_date, y = cured)) +
  geom_point() +
  scale_x_date(
    date_breaks = "1 week",
    date_minor_breaks = "1 day", 
    date_labels = "%d%b")

^{Created on 2020-02-24 by the reprex package (v0.3.0)}

I'd probably have made a quick stab at this if your code didn't require me to install that huge meta-package. — Roland, Feb 24 '20 at 07:25
@Roland Did not mean `tidyverse`? I have revised the question. Thanks — Zhiqiang Wang, Feb 24 '20 at 07:35
I think that the default for minor ticks is the grid. When I needed these sub-markings I used this resource: https://stackoverflow.com/questions/25268264/drawing-minor-ticks-not-grid-ticks-in-ggplot2-in-a-date-format-axis — sconfluentus, Feb 24 '20 at 07:40
@sconfluentus Wouldn't it be a solution to just put major tickmarks everywhere (so on day) and manually puting them in the plot? Looking at the answer posted afterwards it indeed is — Annet, Feb 24 '20 at 08:05
Looks like a Duplicate of https://stackoverflow.com/questions/14490071/adding-minor-tick-marks-to-the-x-axis-in-ggplot2-with-no-labels — tjebo, Feb 24 '20 at 08:30
and https://stackoverflow.com/questions/34533472/insert-blanks-into-a-vector-for-e-g-minor-tick-labels-in-r/34533473#34533473 — tjebo, Feb 24 '20 at 08:31

score 1 · Accepted Answer · answered Feb 24 '20 at 08:06

My work-around is to create a helper-data.frame, with breaks and (a lot of empty) labels. This way, you can use the major-breaks (with ticks!), and just label them with "".

df.labels <- df %>% 
   mutate( x_date = as.Date(date) ) %>% 
   #create labels on every Monday, using lubridate::wday, if not
   #a Monday, add empty "" label.
   mutate( label = ifelse( lubridate::wday( x_date ) == 2, 
                           format( x_date, "%d%b" ), 
                           "" ) )

df %>% 
   mutate(
      x_date = as.Date(date)
   ) %>% 
   ggplot(aes(x = x_date, y = cured)) +
   geom_point() +
   scale_x_date(
      breaks = df.labels$x_date,
      labels = df.labels$label )

Insert ticks for days with labels for weeks

1 Answers1