| gl {base} | R Documentation | 
Generate factors by specifying the pattern of their levels.
gl(n, k, length = n*k, labels = seq_len(n), ordered = FALSE)
n | 
 an integer giving the number of levels.  | 
k | 
 an integer giving the number of replications.  | 
length | 
 an integer giving the length of the result.  | 
labels | 
 an optional vector of labels for the resulting factor levels.  | 
ordered | 
 a logical indicating whether the result should be ordered or not.  | 
The result has levels from 1 to n with each value
replicated in groups of length k out to a total length of
length.
gl is modelled on the GLIM function of the same name.
The underlying factor().
## First control, then treatment:
gl(2, 8, labels = c("Control", "Treat"))
## 20 alternating 1s and 2s
gl(2, 1, 20)
## alternating pairs of 1s and 2s
gl(2, 2, 20)