Zoidie - 1 month ago 6

R Question

I want to do some modifications of a geom_boxplot(). Because my boxplots are really "small" sometimes (see yellow and green clade in the graphic here) i want to highlight the median even more. so is it possible to adjust the thickness of the median line?

Answer

This solution is not obvious from the documentation, but luckily does not require us to edit the source code of `ggplot2`

. After digging through the source of `ggplot2`

I found that the thickness of the median line is controlled by the `fatten`

parameter. By default `fatten`

has a value of two:

```
require(reshape)
require(ggplot2)
cars_melt = melt(cars)
ggplot(aes(x = variable, y = value), data = cars_melt) +
geom_boxplot(fatten = 2)
```

But if we increase the value to for example 4, the median line becomes thicker.

```
ggplot(aes(x = variable, y = value), data = cars_melt) +
geom_boxplot(fatten = 4)
```