[R] filling a vector with a tapply function applied to another vector

I have a data frame with three columns. The first one is filled with factors, the second one with numeric values and the third one is an empty vector. I need fill the third column with the results of the function tapply(secondcolumn,firstcolumn,mean) so that I have for each row of the third column

Re: [R] filling a vector with a tapply function applied to another vector

The first column has 331 rows, the number of factors in the second column is 20 repeated in order to have 331 rows too. What I need is to reapeat in the third column each of the 20 results derived from tapply(firstcolumn,secondcolumn,mean) as many times as each factor appears in the second column.

Re: [R] filling a vector with a tapply function applied to another vector

Thank you so much! That's exactly what I needed! much love -- View this message in context: http://r.789695.n4.nabble.com/filling-a-vector-with-a-tapply-function-applied-to-another-vector-tp3039271p3039396.html Sent from the R help mailing list archive at Nabble.com. ___

[R] conditional mean between two data frames with different levels

Hi guys, I have two data frames: one referred to 2008 and one to 2009. Their structure is identical except for the different data in them. I need to create a vector alfa of the same length of the dataframe 2009 and fill each element with the mean of 2008$var1 conditional to the subgroup indicated

Re: [R] conditional mean between two data frames with different levels

Thank you very much Josh, I guess you`re right. So this is an example: data frame 1 has 2 columns and 10 rows. The first column is "score" a variable indicating the number of goals scored by a football team score<-c(1,2,0,2,1,1,3,2,1,0), column 2 contains the football "teams " where teams<-c(a,b,c

Re: [R] conditional mean between two data frames with different levels

Thank you so much Josh, that's exactly what i needed! Cheers alb -- View this message in context: http://r.789695.n4.nabble.com/conditional-mean-between-two-data-frames-with-different-levels-tp3049010p3049980.html Sent from the R help mailing list archive at Nabble.com.

[R] Optim function with meta parameters

Hi guys. I have a dataset with 4 columns. In the first and second column I have the same qualitative variable referred to different teams of people. There are 10 teams in total and they compete against each other to perform a certain task whose result is stored in the third column for the team rec