fExtremes package

[Peter Maclean]

Hi,
I am new in R and I want to the fExtremes package for data analysis. I usually 
use SAS. I have rainfall data for different points (50 locations). Each point 
has 120 observations. The rainfall data is in the first column (RAIN) and the 
categorical variable that group the data is in the second column (GROUP). The 
data frame is rain.data. How can I use the gevFit function to estimate all three 
parameters by GROUP variable group? In SAS there is a by() function that 
estimate the model by group. However, I would like to move to R.
With thanks, 
 Peter Maclean
Department of Economics
UDSM