Fixing issues with geom_text and axis labels-CodePudding

I have a barplot in which I need to rotate the bar labels giving the Freq values:

library(dplyr)
ggplot(df,
  aes(x = partcl, y = Pct))   
  geom_bar(stat="identity")  
  # rotate x-axis labels by 90°:
  theme(axis.text.x = element_text(angle = 90))  
  # plot `Freq` labels:
  geom_text(aes(x = partcl, y = Pct, label = Freq, angle = 90, hjust = -0.2))

But there are two issues: first, the Freq labels are not fitted to the plotting area; instead the maximum Frequ label (for yeah well) is cut off. Second, the x-axis labels are not perfectly aligned with the x-axis ticks. How can these issues be fixed?

Data:

df <- structure(list(partcl = c("yeah well", "well yeah", "yeah yeah well", 
                                "yeah well well", "yeah well yeah", "well yeah well", "well yeah yeah", 
                                "well yeah yeah yeah", "yeah yeah yeah well", "well yeah well well"
), Freq = c(1515L, 408L, 52L, 20L, 17L, 11L, 8L, 2L, 2L, 1L), 
Pct = c(74.3011280039235, 20.0098087297695, 2.55026974006866, 
        0.980872976949485, 0.833742030407062, 0.539480137322217, 
        0.392349190779794, 0.0980872976949485, 0.0980872976949485, 
        0.0490436488474743)), class = c("tbl_df", "tbl", "data.frame"
        ), row.names = c(NA, -10L))

CodePudding user response：

For the ticks set vjust=.5 as by default theme_grey uses vjust=1. For the labels I don't know of any out-of-the-box option except for increasing the expansion of the y scale:

library(ggplot2)

ggplot(df, aes(x = partcl, y = Pct))   
  geom_bar(stat="identity")  
  # rotate x-axis labels by 90°:
  theme(axis.text.x = element_text(angle = 90, vjust = .5))  
  # plot `Freq` labels:
  geom_text(aes(x = partcl, y = Pct, label = Freq, angle = 90, hjust = -0.2))  
  scale_y_continuous(expand = expansion(mult = c(0, .15)))

CodePudding user response：

There are two questions in one here to answer:

How to adjust the position of the x axis labels? Use vjust= and hjust= arguments inside element_text() to position the text relative to the anchor point. When rotated, you'll need to fix this (because it's different for how you would position horizontal text). Use vjust=0.5 to set the middle of the text to align with the tick mark. Use hjust=1 to set the text aligned to the "right" and move it to be next to the tick mark. Note that your text is rotated 90 degrees, so "horizontal" and "vertical" should be understood relative to the direction of the text.
How to show the text above the bar? For this, you will want to expand the y axis. You can do this via scale_y_continuous(expand = expansion(mult=c(0.05, 0.15))). The vector assigned to mult= has two values. The first value is applied to the lower part of the axis (default is around 0.05, so no change), and the second value is applied to the upper part. Here we expand by about 15% based on the data (rather than about 5%, which is default).

Here's the code and final look:

ggplot(df,
       aes(x = partcl, y = Pct))   
  geom_bar(stat="identity")  
  # rotate x-axis labels by 90°:
  theme(axis.text.x = element_text(angle = 90, vjust=0.5, hjust=1))  
  # plot `Freq` labels:
  geom_text(aes(x = partcl, y = Pct, label = Freq, angle = 90, hjust = -0.2))  
  scale_y_continuous(expand = expansion(mult=c(0.05, 0.15)))