CODEWITHSUNDEEP
rggplot2
RickDeShon
RickDeShon

Reputation: 21

ggplot2: combined bar and line chart alignment

I want to chart one variable using bars and another using lines in a single plot. Here's a minimal example:

df <- data.frame(
   Pct_F = c(40,50,60,70,80,90),
   Pct_B = c(50,60,70,80,90,95),
   Time  = c("Pre","Pre","Pre","Post","Post","Post"),
   Variable = c("Var1","Var2","Var3","Var1","Var2","Var3")
)

ggplot(df)+
   geom_bar(aes(x = Variable, y = Pct_F, fill = Time), stat="identity", width = 0.5, position = "dodge")+
   geom_line(aes(x = Variable, y=Pct_B, group = Time, colour=Time), stat="identity", size=2)+
   scale_y_continuous(limits = c(0,100))+
   coord_flip()+
   labs(title="Test Chart", x= "", y = "Percent", caption = "(Note: Bars refer to Pct_F and lines refer to Pct_B)")

Here's the resulting plot: bar and line plot

Notice how the line is aligned with the edge of the bars? How can I get the lines to align with the center of the bars?

Thank you!

Upvotes: 2

Views: 172

Answers (1)

Algebreaker
Algebreaker

Reputation: 118

You can add it manually with position_dodge(). Also, geom_col is what you use when you want geom_bar with stat = "identity".

library(ggplot2)
df <- data.frame(
  Pct_F = c(40,50,60,70,80,90),
  Pct_B = c(50,60,70,80,90,95),
  Time  = c("Pre","Pre","Pre","Post","Post","Post"),
  Variable = c("Var1","Var2","Var3","Var1","Var2","Var3")
)
dodge = position_dodge(0.5)
ggplot(df)+
  geom_col(aes(x = Variable, y = Pct_F, fill = Time), width = 0.5, position = "dodge")+
  geom_line(aes(x = Variable, y=Pct_B, group = Time, colour=Time), stat="identity", size=2, position = dodge)+
  scale_y_continuous(limits = c(0,100))+
  coord_flip()+
  labs(title="Test Chart", x= "", y = "Percent", caption = "(Note: Bars refer to Pct_F and lines refer to Pct_B)")

Output: enter image description here

Upvotes: 2

Related Questions