If I am using R to plot. How can I assign a particular shape to data points belonging to one category (using the pch argument to plot()) based on a column in my data frame that has the categorical data? Will using as.factor() to group data and then using pch help ?
You mean something like this...?
plot(Sepal.Length ~ Petal.Length,
xlab = "Petal Length (cm)",
ylab = "Sepal Length (cm)",
pch = c(16, 17, 18)[as.numeric(Species)], # different 'pch' types
main = "Anderson Iris Dataset",
col = c("red", "green","blue")[as.numeric(Species)],
data = iris)
Which produces:
来源：https://stackoverflow.com/questions/12919816/plotting-in-different-shapes-using-pch-argument