question: ragged array
Hi: Try this: ratok <- data.frame(Id = rep(1:3, 3:1), value = c(2, 3, 4, 2, 1, 5)) aggregate(value ~ Id, data = ratok, FUN = mean) Id value 1 1 3.0 2 2 1.5 3 3 5.0 aggregate() returns a data frame with the Id variable and mean(value). HTH, Dennis On Sun, Oct 16, 2011 at 6:53 AM, Helene Schreyer
<helene.schreyer at gmail.com> wrote:
Hello, I have a big problem which I?m just not able to solve. I created the following mean value from the following dataset structure: Id |value 1 ?| 2 1 ?| 3 1 ?| 4 2 ?| 2 2 ?| 1 3 ?| 5 4 ?| 3 etc.|etc. with the command: mean_rating <- tapply(ratok$value, ratok$project_id , mean,simplify = FALSE) this gives me ?a ragged array:
mean_rating [1]
$`14` ###########==project_id [1] 3.933333 #######==mean value
dim (mean_rating)
[1] 2214
I want to separate now the project_id from the mean value. So that I have
two separate ? ? ? ? columns (2 dimension).
How can I separate a ragged array into two variables?
*Additional information:*
I need this information to put the mean value into another dataset
(?projok?) at the correct project_id.
I would do that as follow:
k=projok[,1]
for(i in 1:2442) {
? ? ? ? ? ? ? ?projLineNb = which(mean_rating$project_id==k[i])
? ? ? ? ? ? ? ?projok$mean[i] = mean_rating$value[projLineNb]
}
But with a ragged array I can not refer to project_id. Or is there a
possibility that I can refer to the project_id in a ragged array?
mean_rating [[1]]
[1] 3.933333 ==I can refer to the value only Thank you very much Best, Helene ? ? ? ?[[alternative HTML version deleted]]
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