Removing space between two vertically aligned ggplot plots with grid.draw

Question

I'm trying two combine to plots created with ggplot2 that have the same x axis into one figure. I basically followed the instructions found here: https://gist.github.com/tomhopper/faa24797bb44addeba79.

I modified the code to be as follows:

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

df <- data.frame(DateTime = ymd("2010-07-01") + c(0:8760) * hours(2), series1 = rnorm(8761), series2 = rnorm(8761, 100))
df_1<- df %>% select(DateTime, series1) %>% na.omit()
df_2 <- df %>% select(DateTime, series2) %>% na.omit()


plot1 <- ggplot(df_1) +
    geom_point(aes(x = DateTime, y = series1), size = 0.5, alpha = 0.75) +
    labs(x="", y="Red dots / m") +
    theme(axis.title.x = element_blank(), axis.text.x=element_blank())

plot2 <- ggplot(df_2) +
    geom_point(aes(x = DateTime, y = series2), size = 0.5, alpha = 0.75) +
    labs(x="", y="Blue drops / L") +
    theme(axis.title.x = element_blank())

grid.newpage()
grid.draw(rbind(ggplotGrob(plot1), ggplotGrob(plot2), size = "last"))

This gives me the following picture:

How can I remove the space between the plots? I tried to change the margins in each separate plot with theme(plot.margin = unit(c(-1,1.2,0,0), "cm")), but this gets lost when combining the plots in grid.draw.

I know that there are similar posts, but I cannot find any solution which works for my case. I would appreciate any hints on this!

With this example, you might be better off using facets. If you want to fix the margins, remember to remove the relevant margin of both plots — Richard Telford, Feb 07 '20 at 11:54

score 2 · Accepted Answer · answered Feb 07 '20 at 13:58

You can follow the approach from this question to set the bottom margin of plot.margin as negative in the first/upper plot and the top margin of the plot.margin argument as negative in the second/lower plot. It might take some finessing of what negative values to use, but you should be able to find something that works for you!

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

df <- data.frame(DateTime = ymd("2010-07-01") + c(0:8760) * hours(2), series1 = rnorm(8761), series2 = rnorm(8761, 100))
df_1<- df %>% select(DateTime, series1) %>% na.omit()
df_2 <- df %>% select(DateTime, series2) %>% na.omit()


plot1 <- ggplot(df_1) +
    geom_point(aes(x = DateTime, y = series1), size = 0.5, alpha = 0.75) +
    labs(x="", y="Red dots / m") +
    theme(axis.title.x = element_blank(), axis.text.x=element_blank(),
          plot.margin=unit(c(0.9,1,-0.175,1), "cm"))

plot2 <- ggplot(df_2) +
    geom_point(aes(x = DateTime, y = series2), size = 0.5, alpha = 0.75) +
    labs(x="", y="Blue drops / L") +
    theme(axis.title.x = element_blank(),
          plot.margin=unit(c(-0.175,1,0.9,1), "cm")
          )

grid.newpage()
grid.draw(rbind(ggplotGrob(plot1), ggplotGrob(plot2), size = "last"))

With the output:

I actually tried that before, then it didn't work, but starting a new R session it suddenly worked. Thanks anyways! :) — wylierose, Feb 07 '20 at 14:12
I was wondering that myself! Sometimes the reset is all it takes :) glad to help! — krfurlong, Feb 07 '20 at 14:56

Removing space between two vertically aligned ggplot plots with grid.draw

1 Answers1