[R] data frame row statistics (mean)?

[Douglas M. Hultstrand]

Hello,

I am trying to calculate the mean value of each row in a data frame (d), 
I am having troubles and getting errors using the code I have written.  
Below is a brief example of the code, any thought or suggestions would 
be great.

Thank you for your time,
Doug


# Example Code:
d <- data.frame(st1=c(1,2,3,4), st2=c(2,5,6,7), st3=c(5,5,NA,7), 
st4=c(6,5,7,8))
avg <- rep(NA,length(d[,1]))

for (i in 1:length(d[,1])) {
        avg[i] = mean(d[i,1:4], na.rm=TRUE)
}

# Final Output wanted.
  st1 st2 st3 st4  avg
1   1   2   5   6 3.50
2   2   5   5   5 4.25
3   3   6  NA   7 5.33
4   4   7   7   8 6.50

-- 
---------------------------------
Douglas M. Hultstrand, MS
Senior Hydrometeorologist
Metstat, Inc. Windsor, Colorado
voice: 720.771.5840
email: dmhultst at metstat.com
web: http://www.metstat.com