adding x and y axis labels in ggplot2

ggplot2, label, r

Solution

[Note: edited to modernize ggplot syntax]

Your example is not reproducible since there is no `ex1221new` (there is an `ex1221` in `Sleuth2`, so I guess that is what you meant). Also, you don't need (and shouldn't) pull columns out to send to `ggplot`. One advantage is that `ggplot` works with `data.frame`s directly.

You can set the labels with `xlab()` and `ylab()`, or make it part of the `scale_*.*` call.

library("Sleuth2")
library("ggplot2")
ggplot(ex1221, aes(Discharge, Area)) +
  geom_point(aes(size=NO3)) + 
  scale_size_area() + 
  xlab("My x label") +
  ylab("My y label") +
  ggtitle("Weighted Scatterplot of Watershed Area vs. Discharge and Nitrogen Levels (PPM)")

ggplot(ex1221, aes(Discharge, Area)) +
  geom_point(aes(size=NO3)) + 
  scale_size_area("Nitrogen") + 
  scale_x_continuous("My x label") +
  scale_y_continuous("My y label") +
  ggtitle("Weighted Scatterplot of Watershed Area vs. Discharge and Nitrogen Levels (PPM)")

An alternate way to specify just labels (handy if you are not changing any other aspects of the scales) is using the `labs` function

ggplot(ex1221, aes(Discharge, Area)) +
  geom_point(aes(size=NO3)) + 
  scale_size_area() + 
  labs(size= "Nitrogen",
       x = "My x label",
       y = "My y label",
       title = "Weighted Scatterplot of Watershed Area vs. Discharge and Nitrogen Levels (PPM)")

which gives an identical figure to the one above.

Problem

How do I change the x and y labels on this graph please? ``` library(Sleuth2) library(ggplot2) discharge<-ex1221new$Discharge area<-ex1221new$Area nitrogen<-ex1221new$NO3 p <- ggplot(ex1221new, aes(discharge, area), main="Point") p + geom_point(aes(size= nitrogen)) + scale_area() + opts(title = expression("Weighted Scatterplot of Watershed Area vs. Discharge and Nitrogen Levels (PPM)"), subtitle="n=41") ```

Original source