R – How to put labels over geom_bar for each bar in R with ggplot2

bar-chartggplot2r

I've found this, How to put labels over geom_bar in R with ggplot2, but it just put labels(numbers) over only one bar.

Here is, let's say, two bars for each x-axis, how to do the same thing?

My data and code look like this:

dat <- read.table(text = "sample Types Number
sample1 A   3641
sample2 A   3119
sample1 B   15815
sample2 B   12334
sample1 C   2706
sample2 C   3147", header=TRUE)

library(ggplot2)
bar <- ggplot(data=dat, aes(x=Types, y=Number, fill=sample)) + 
  geom_bar(position = 'dodge') + geom_text(aes(label=Number))

Then, we'll get:
enter image description here

It seems that the number texts are also positioned in the "dodge" pattern.
I've searched geom_text manual to find some information, but cannot make it work.

Suggestions?

Best Answer

Try this:

ggplot(data=dat, aes(x=Types, y=Number, fill=sample)) + 
     geom_bar(position = 'dodge', stat='identity') +
     geom_text(aes(label=Number), position=position_dodge(width=0.9), vjust=-0.25)

ggplot output

Related Solutions

R – How to set limits for axes in ggplot2 R plots

Basically you have two options

scale_x_continuous(limits = c(-5000, 5000))

coord_cartesian(xlim = c(-5000, 5000))

Where the first removes all data points outside the given range and the second only adjusts the visible area. In most cases you would not see the difference, but if you fit anything to the data it would probably change the fitted values.

You can also use the shorthand function xlim (or ylim), which like the first option removes data points outside of the given range:

+ xlim(-5000, 5000)

For more information check the description of coord_cartesian.

The RStudio cheatsheet for ggplot2 makes this quite clear visually. Here is a small section of that cheatsheet:

Distributed under CC BY.

R – How to put labels over geom_bar in R with ggplot2

To plot text on a ggplot you use the geom_text. But I find it helpful to summarise the data first using ddply

dfl <- ddply(df, .(x), summarize, y=length(x))
str(dfl)

Since the data is pre-summarized, you need to remember to change add the stat="identity" parameter to geom_bar:

ggplot(dfl, aes(x, y=y, fill=x)) + geom_bar(stat="identity") +
    geom_text(aes(label=y), vjust=0) +
    opts(axis.text.x=theme_blank(),
        axis.ticks=theme_blank(),
        axis.title.x=theme_blank(),
        legend.title=theme_blank(),
        axis.title.y=theme_blank()
)

enter image description here

Best Answer

Related Solutions

R – How to set limits for axes in ggplot2 R plots

R – How to put labels over geom_bar in R with ggplot2

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