Reputation: 1139
I am new to learning R. I wanted to know how I can asssign a categorical value to observations I have read in as a dataframe. For eg I have data for m variables from n samples and I want to assign some samples as group 1 and some samples as group 2 and so on. Also, how can I visualise different groups in different colors when I plot them?
Upvotes: 2
Views: 1343
Reputation: 60944
Let's say you have the following data:
spam = data.frame(value = runif(100))
you can assign random group membership like this:
spam[["group"]] = sample(c("group1", "group2"), nrow(spam), replace = TRUE)
> head(spam)
value group
1 0.1385715 group1
2 0.1785452 group1
3 0.7407510 group2
4 0.5867080 group1
5 0.1514461 group1
6 0.3009905 group1
Plotting the groups with different colors can easily be done using ggplot2
:
require(ggplot2)
ggplot(aes(x = 1:nrow(spam), y = value, color = group), data = spam) +
geom_point()
Upvotes: 5