Dear R-helper,
I am working on a very large data frame and I am trying to add a new column
and write in it with certain conditions. I have try to use this code with
the data frame p :
ID = 0
p[,"newColumn"]<-
ifelse (p$flagFoehn3_durr == 1,
ifelse(p$Guetsch == 0,
ID <<- ID ++
,
ID
)
,
0
)
What I am trying to do is to increment the ID when p$Guetsch == 0 and to
put this result in the column. The problem is that ID does not increment
itself.
An other way is to use a loop for like this example :
ID = 0
for (s in 1:(nrow(z))){
z[s,"newColumn"]<-
if (z$flagFoehn3_durr[s] == 1){
if(z$flagFoehn3_durr[s-1] == 0){
ID <<-ID+1
}else{
ID
}
}else{
0
}
}
This work perfectly, but the problem is that it will take me more than a
month to run it.
Is there a way to increment with the first code I used or a way of running
the second code faster (I have more than 1 million rows)
Thanks!
Cheers,
Damien
[[alternative HTML version deleted]]
______________________________________________
[email protected] mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
