Tick marks either side of dates in ggplot

user_1130279 0
Viewed 131

Ggplot adds ticks marks centrally using this code:

tibble(year = 2010:2020, count = sample(1:100, 11)) %>%
  mutate(year = paste0("01/01/", year)) %>%
  mutate(year = dmy(year)) %>%
  ggplot +
  geom_bar(aes(year, count), stat = "identity", width = 240, position = position_dodge(width = 0.1)) +
  scale_x_date(date_labels = "%y", date_breaks = "1 year") +
  scale_y_continuous(limits = c(0,100), expand = c(0, 0)) +
  theme_classic()

enter image description here

But I need tick marks either side of the year. I have photoshopped in the tick marks plot to show where I need them. What code can I use to add ticks marks either side of year?

enter image description here

ggplot2 axis-labels r
1 Answers

You can draw the tick marks yourself with geom_segment(), turn off the clipping and hide the default ones.

library(ggplot2)
library(dplyr)
library(lubridate)

tbl <- tibble(year = 2010:2020, count = sample(1:100, 11)) %>%
  mutate(year = paste0("01/01/", year)) %>%
  mutate(year = dmy(year))

ggplot(tbl) +
  geom_bar(aes(year, count), stat = "identity", width = 240, position = position_dodge(width = 0.1)) +
  geom_segment(aes(x = year, xend = year), y = 0, yend = -1, 
               colour ="black", position = position_nudge(x = 240/2)) +
  geom_segment(aes(x = year, xend = year), y = 0, yend = -1, 
               colour ="black", position = position_nudge(x = -240/2)) +
  scale_x_date(date_labels = "%y", date_breaks = "1 year") +
  scale_y_continuous(limits = c(0,100), expand = c(0, 0),
                     oob = scales::oob_keep) +
  coord_cartesian(clip = "off") +
  theme_classic() +
  theme(axis.ticks = element_blank())

Created on 2021-04-10 by the reprex package (v1.0.0)

user_113748270
Related