Two vertical bar charts with shared x-axis in ggplot2

Question

I would like to make graphs similar to this

How can I make graphs like this using R?

I have read Two horizontal bar charts with shared axis in ggplot2 (similar to population pyramid) and he can make horizontial bar charts using the following R code:

  g.mid<-ggplot(tp07,aes(x=1,y=sch))+geom_text(aes(label=sch))+
geom_segment(aes(x=0.94,xend=0.96,yend=sch))+
geom_segment(aes(x=1.04,xend=1.065,yend=sch))+
ggtitle("")+
   ylab(NULL)+
   scale_x_continuous(expand=c(0,0),limits=c(0.94,1.065))+
   theme(axis.title=element_blank(),
         panel.grid=element_blank(),
         axis.text.y=element_blank(),
         axis.ticks.y=element_blank(),
       panel.background=element_blank(),
         axis.text.x=element_text(color=NA),
         axis.ticks.x=element_line(color=NA),
         plot.margin = unit(c(1,-1,1,-1), "mm"))
 g1 <- ggplot(data = tp07, aes(x = sch, y = ans0)) +
 geom_bar(stat = "identity") + ggtitle("Number of student never or Seldom have breakfast") +
 theme(axis.title.x = element_blank(), 
         axis.title.y = element_blank(), 
         axis.text.y = element_blank(), 
         axis.ticks.y = element_blank(), 
         plot.margin = unit(c(1,-1,1,0), "mm")) +
   scale_y_reverse() + coord_flip()
 g2 <- ggplot(data = tp07, aes(x = sch, y = ans7)) +xlab(NULL)+
geom_bar(stat = "identity") + ggtitle("No. of students have breakfsat 7 days a week") +
 theme(axis.title.x = element_blank(), axis.title.y = element_blank(), 
         axis.text.y = element_blank(), axis.ticks.y = element_blank(),
         plot.margin = unit(c(1,0,1,-1), "mm")) +
 coord_flip()

library(gridExtra)
gg1 <- ggplot_gtable(ggplot_build(g1))
gg2 <- ggplot_gtable(ggplot_build(g2))
gg.mid <- ggplot_gtable(ggplot_build(g.mid))

grid.arrange(gg1,gg.mid,gg2,ncol=3,widths=c(4/9,1/9,4/9))

how can I change it from horizontal to vertical? And I would like to keep the x-axis in the middle part of the graph that separate the two variables.

Possible duplicate of [How do you create a bar plot for two variables mirrored across the x-axis in R?](http://stackoverflow.com/questions/6999144/how-do-you-create-a-bar-plot-for-two-variables-mirrored-across-the-x-axis-in-r) — Cyrus Mohammadian, Sep 15 '16 at 05:52
@CyrusMohammadian but I how can I make the x-axis in the middle of the graph instead of placing it in the bottom — alexms, Sep 16 '16 at 13:33
Try adding it along with `stat = "identity"`, inside `geom_bar()` — Sowmya S. Manian, Sep 16 '16 at 13:56
Can you add an example of the data frame you are using, so we can test the code? — thepule, Sep 16 '16 at 15:19
@alexms im not sure what you mean by that comment, in the link i posted the x axis is in the middle...don't look at the question plots look at the plots posted in the answer... — Cyrus Mohammadian, Sep 16 '16 at 18:15
@thepule I am sorry, below is the example sch<-c("sch_a","sch_b","sch_c","sch_d","sch_d") ans0<-c(2,4,7,8,2) ans7<-c(4,13,4,6,0) sch<-c("sch_a","sch_b","sch_c","sch_d","sch_d") tp07<-data.frame(cbind(sch,ans0,ans7)) — alexms, Sep 18 '16 at 10:22
@CyrusMohammadian I meant place all the x-axis labels in the middle part of the graph,separating the two vertical bar chart. — alexms, Sep 18 '16 at 10:24
There is some error in `g1` you have to rectify that first. `Error: Discrete value supplied to continuous scale In addition: Warning message: In Ops.factor(x) : ‘-’ not meaningful for factors` — Sowmya S. Manian, Sep 18 '16 at 15:30

score 1 · Accepted Answer · answered Sep 18 '16 at 16:33

Assuming tp07 is the following:

tp07 <- structure(list(sch = structure(c(1L, 2L, 3L, 4L, 4L), .Label = c("sch_a", 
"sch_b", "sch_c", "sch_d"), class = "factor"), ans0 = c(1, 2, 
3, 4, 1), ans7 = c(3, 2, 3, 4, 1)), .Names = c("sch", "ans0", 
"ans7"), row.names = c(NA, -5L), class = "data.frame")

The code below does the job:

g.mid_ <- ggplot(tp07,aes(x=sch,y=1))+geom_text(aes(label=sch))+
    geom_segment(aes(y=0.94,yend=0.96,xend=sch))+
    geom_segment(aes(y=1.04,yend=1.065,xend=sch))+
    ggtitle("") +
    xlab(NULL) +
    scale_y_continuous(expand=c(0,0),limits=c(0.94,1.065))+
    theme(axis.title=element_blank(),
          panel.grid=element_blank(),
          axis.text.y=element_blank(),
          axis.ticks.y=element_blank(),
          panel.background=element_blank(),
          axis.text.x=element_text(color=NA),
          axis.ticks.x=element_line(color=NA),
          plot.margin = unit(c(1,-1,1,-1), "mm"))


g1_ <- ggplot(data = tp07, aes(x = sch, y = ans0)) +
    geom_bar(stat = "identity", position = "identity") +
    theme(axis.title.x = element_blank(),
          axis.text.x = element_blank(), 
          axis.ticks.x = element_blank(), 
          plot.margin = unit(c(1,-1,1,0), "mm")) +
    scale_y_reverse()


g2_ <- ggplot(data = tp07, aes(x = sch, y = ans7)) +xlab(NULL)+
    geom_bar(stat = "identity") +
    theme(axis.title.x = element_blank(), 
          axis.text.x = element_blank(), 
          axis.ticks.x = element_blank(),
          plot.margin = unit(c(1,0,1,-1), "mm")) 


gg1 <- ggplot_gtable(ggplot_build(g1_))
gg2 <- ggplot_gtable(ggplot_build(g2_))
gg.mid <- ggplot_gtable(ggplot_build(g.mid_))

grid.arrange(gg2, gg.mid,gg1,nrow=3, heights=c(4/10,2/10,4/10))

The output is:

But it there any ways to make the labels in the middle part of the bar? As when it comes to having more than 100 rows of data, the labels are not under/on the right bar. And can i display the labels in vertical instead of horizontal? Thanks you! — alexms, Sep 19 '16 at 04:46
The problem is solved using the following code, thanks a lot for your help! — alexms, Sep 19 '16 at 08:38

Two vertical bar charts with shared x-axis in ggplot2

1 Answers1