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How to set limits for axes in ggplot2 R plots?

I plot the following:

library(ggplot2)    

carrots <- data.frame(length = rnorm(500000, 10000, 10000))
cukes <- data.frame(length = rnorm(50000, 10000, 20000))
carrots$veg <- 'carrot'
cukes$veg <- 'cuke'
vegLengths <- rbind(carrots, cukes)

ggplot(vegLengths, aes(length, fill = veg)) +
 geom_density(alpha = 0.2)

Now say, I only want to plot the region between x=-5000 to 5000, instead of the entire range.

How can I do that?


A
Axeman

Basically you have two options

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

or

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:

https://i.stack.imgur.com/ciyvf.png

Distributed under CC BY.


there's also now library(scales); ... + scale_x_continuous(limits = c(-5000, 5000), oob=squish) (the default is oob=censor); see ?squish, ?censor: groups.google.com/forum/#!topic/ggplot2/AsJ6xpmR9tU
NB. this might be problematic if you're dealing with lines/polygons where some vertices are outside the limits, as the whole object is removed from the plot
@geotheory: is that also true of the coord_cartesian approach?
No I should've been more specific, just the first method
In practice, for 'printing' purposes, with coord_cartesian(xlim = you probably need to reset ylim as well, and reset the label and grid breaks.
B
Bill

Quick note: if you're also using coord_flip() to flip the x and the y axis, you won't be able to set range limits using coord_cartesian() because those two functions are exclusive (see here).

Fortunately, this is an easy fix; set your limits within coord_flip() like so:

p + coord_flip(ylim = c(3,5), xlim = c(100, 400))

This just alters the visible range (i.e. doesn't remove data points).


I similar but harder question posted here stackoverflow.com/questions/61531149/… on how to limit one SIDE ONLY