Setting a dummy aesthetic
In the last chapter you saw that all the visible aesthetics can serve as attributes and aesthetics, but I very conveniently left out x and y. That's because although you can make univariate plots (such as histograms, which you'll get to in the next chapter), a y-axis will always be provided, even if you didn't ask for it.
You can make univariate plots in ggplot2, but you will need to add a fake y axis by mapping y to zero.
When using setting y-axis limits, you can specify the limits as separate arguments, or as a single numeric vector. That is, ylim(lo, hi) or ylim(c(lo, hi)).
Deze oefening maakt deel uit van de cursus
Introduction to Data Visualization with ggplot2
Praktische interactieve oefening
Probeer deze oefening eens door deze voorbeeldcode in te vullen.
# Plot 0 vs. mpg
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# Add jitter
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