This post describes a method to create a two-line x-axis (year below months) on a time series plot. Unfortunately, the method that I use from this post (option 2) is not compatible with ggsave()
.
library(tidyverse)
library(lubridate)
df <- tibble(
date = as.Date(41000:42000, origin = "1899-12-30"),
value = c(rnorm(500, 5), rnorm(501, 10))
)
p <- ggplot(df, aes(date, value)) +
geom_line() +
geom_vline(
xintercept = as.numeric(df$date[yday(df$date) == 1]), color = "grey60"
) +
scale_x_date(date_labels = "%b", date_breaks = "month", expand = c(0, 0)) +
theme_bw() +
theme(panel.grid.minor.x = element_blank()) +
labs(x = "")
# Get the grob
g <- ggplotGrob(p)
# Get the y axis
index <- which(g$layout$name == "axis-b") # which grob
xaxis <- g$grobs[[index]]
# Get the ticks (labels and marks)
ticks <- xaxis$children[[2]]
# Get the labels
ticksB <- ticks$grobs[[2]]
# Edit x-axis label grob
# Find every index of Jun in the x-axis labels and a year label
junes <- grep("Jun", ticksB$children[[1]]$label)
ticksB$children[[1]]$label[junes] <-
paste0(
ticksB$children[[1]]$label[junes],
"\n ", # adjust the amount of spaces to center the year
unique(year(df$date))
)
# Center the month labels between ticks
ticksB$children[[1]]$label <-
paste0(
paste(rep(" ", 12), collapse = ""), # adjust the integer to center month
ticksB$children[[1]]$label
)
# Put the edited labels back into the plot
ticks$grobs[[2]] <- ticksB
xaxis$children[[2]] <- ticks
g$grobs[[index]] <- xaxis
# Draw the plot
grid.newpage()
grid.draw(g)
# Save the plot
ggsave("plot.png", width = 11, height = 8.5, units = "in")
A plot is saved, but without the years. How do I ggsave()
the final plot from grid.draw(g)
? This grid.draw(g)
plot is shown below, but the actual plot.png
file is slightly different, with the three years 2012
, 2013
and 2014
omitted.
library(tidyverse)
library(lubridate)
library(scales)
set.seed(123)
df <- tibble(
date = as.Date(41000:42000, origin = "1899-12-30"),
value = c(rnorm(500, 5), rnorm(501, 10))
)
# create year column for facet
df <- df %>%
mutate(year = as.factor(year(date)))
p <- ggplot(df, aes(date, value)) +
geom_line() +
geom_vline(xintercept = as.numeric(df$date[yday(df$date) == 1]), color = "grey60") +
scale_x_date(date_labels = "%b",
breaks = pretty_breaks(),
expand = c(0, 0)) +
# switch the facet strip label to the bottom
facet_grid(.~ year, space = 'free_x', scales = 'free_x', switch = 'x') +
labs(x = "") +
theme_bw(base_size = 14, base_family = 'mono') +
theme(panel.grid.minor.x = element_blank()) +
# remove facet spacing on x-direction
theme(panel.spacing.x = unit(0,"line")) +
# switch the facet strip label to outside
# remove background color
theme(strip.placement = 'outside',
strip.background.x = element_blank())
p
ggsave("plot.png", plot = p,
type = "cairo",
width = 11, height = 8.5, units = "in",
dpi = 150)
Using theme_classic()
p <- ggplot(df, aes(date, value)) +
geom_line() +
geom_vline(xintercept = as.numeric(df$date[yday(df$date) == 1]), color = "grey60") +
scale_x_date(date_labels = "%b",
breaks = pretty_breaks(),
expand = c(0, 0)) +
# switch the facet strip label to the bottom
facet_grid(.~ year, space = 'free_x', scales = 'free_x', switch = 'x') +
labs(x = "") +
theme_classic(base_size = 14, base_family = 'mono') +
theme(panel.grid.minor.x = element_blank()) +
# remove facet spacing on x-direction
theme(panel.spacing.x = unit(0,"line")) +
# switch the facet strip label to outside
# remove background color
theme(strip.placement = 'outside',
strip.background.x = element_blank())
p
Add the top and right most borders
ymax <- ceiling(1.1 * max(df$value, na.rm = TRUE))
xmax <- max(df$date, na.rm = TRUE)
p <- ggplot(df, aes(date, value)) +
geom_line() +
geom_vline(xintercept = as.numeric(df$date[yday(df$date) == 1]), color = "grey60") +
scale_x_date(date_labels = "%b",
breaks = pretty_breaks(),
expand = c(0, 0)) +
# switch the facet strip label to the bottom
facet_grid(.~ year, space = 'free_x', scales = 'free_x', switch = 'x') +
labs(x = "") +
theme_classic(base_size = 14, base_family = 'mono') +
theme(panel.grid.minor.x = element_blank()) +
# remove facet spacing on x-direction
theme(panel.spacing.x = unit(0,"line")) +
# switch the facet strip label to outside
# remove background color
theme(strip.placement = 'outside',
strip.background.x = element_blank()) +
### add top and right most borders
scale_y_continuous(expand = c(0, 0), limits = c(0, ymax)) +
geom_hline(yintercept = ymax) +
geom_vline(xintercept = as.numeric(df$date[df$date == xmax])) +
theme(panel.grid.major = element_line())
p
Created on 2018-10-01 by the reprex package (v0.2.1.9000)
Taken from Tung
comments above. Add the following at the end of the code chunk in the op's question.
ggsave(
"plot.png",
plot = g,
type = "cairo",
width = 11,
height = 8.5,
units = "in",
dpi = 150
)