Hi: > I have some data 'myData' in wide form (attached at the end), and > would like to convert it to long form. I wish to have five variables > in the result: > > 1) Subj: factor > 2) Group: between-subjects factor (2 levels: s / w) > 3) Reference: within-subject factor (2 levels: Me / She) > 4) F: within-subject factor (2 levels: F1 / F2) > 5) J: within-subject factor (2 levels: J1 / J2)
I don't see how you can get all of 3-5 given the way your data is structured. The problem is that each column contains two of the three variables you want, but not all three. I can see a way to get Subj Group Ref Time F J S1 s Me 1 4 5 S1 s Me 2 3 6 S1 s She 1 6 10 S1 s She 2 6 9 or an 8 line version with Ref (4 Me, 4 She), Factor (F1, J1, F2, J2) repeated twice and the appropriate response vector, but not a way where you have three columns for Ref, F and J. For example, what is the 'J' for MeF1 or the F for SheJ2? With that, here are a few stabs using the reshape2 package. The first step is to do a little renaming of your data frame so that one can use the colsplit() function to generate a new set of variables. names(myData) <- c("Group", "Me_F_1", "Me_J_1", "She_F_1", "She_J_1", "Me_F_2", "Me_J_2", "She_F_2", "She_J_2", "Subj") library('plyr') library('reshape2') # collapses the eight columns to be reshaped into a factor named # variable with a corresponding variable named value mData <- melt(myData, id = c('Subj', 'Group')) head(mData) # Split the original variables into three new columns, named # Ref, Var and Time, respectively: newvars <- colsplit(mData$variable, '_', c('Ref', 'Var', 'Time')) # Append these to the melted data frame and remove 'variable' mData2 <- cbind(mData, newvars)[, -3] # This comes closest to your original intent: mData3 <- arrange(mData2, Subj, Ref, Var, Time) head(mData3, 8) Subj Group value Ref Var Time 1 S1 s 4 Me F 1 2 S1 s 3 Me F 2 3 S1 s 5 Me J 1 4 S1 s 6 Me J 2 5 S1 s 6 She F 1 6 S1 s 6 She F 2 7 S1 s 10 She J 1 8 S1 s 9 She J 2 # Some rearrangements to consider: mData4 <- cast(mData3, Subj + Group + Ref + Time ~ Var, value_var = 'value') head(mData4, 4) Subj Group Ref Time F J 1 S1 s Me 1 4 5 2 S1 s Me 2 3 6 3 S1 s She 1 6 10 4 S1 s She 2 6 9 mData5 <- cast(mData3, Subj + Group + Ref + Var ~ Time, value_var = 'value') head(mData5, 4) Subj Group Ref Var 1 2 1 S1 s Me F 4 3 2 S1 s Me J 5 6 3 S1 s She F 6 6 4 S1 s She J 10 9 If you like this one, it's probably a good idea to rename the last two columns 'Time1' and 'Time2' or something similar. HTH, Dennis On Thu, Oct 6, 2011 at 1:28 PM, Gang Chen <gangch...@gmail.com> wrote: > I have some data 'myData' in wide form (attached at the end), and > would like to convert it to long form. I wish to have five variables > in the result: > > 1) Subj: factor > 2) Group: between-subjects factor (2 levels: s / w) > 3) Reference: within-subject factor (2 levels: Me / She) > 4) F: within-subject factor (2 levels: F1 / F2) > 5) J: within-subject factor (2 levels: J1 / J2) > > As this is the first time I'm learning such a conversion, could > someone help me out? > > Many thanks, > Gang > >> myData > > Group MeF1 MeJ1 SheF1 SheJ1 MeF2 MeJ2 SheF2 SheJ2 Subj > 1 s 4 5 6 10 3 6 6 9 S1 > 2 s 6 5 5 6 4 3 5 6 S2 > 3 s 7 4 6 5 7 4 5 3 S3 > 4 s 8 5 8 7 7 1 8 6 S4 > 5 s 10 6 4 7 9 6 4 6 S5 > 6 s 5 2 4 7 4 1 4 2 S6 > 7 s 13 2 10 4 11 2 4 3 S7 > 8 s 8 1 3 11 6 0 3 10 S8 > 9 s 6 9 5 8 6 8 5 6 S9 > 10 s 14 5 6 10 13 5 5 10 S10 > 11 s 15 2 18 2 14 1 18 2 S11 > 12 s 6 9 4 9 5 11 3 8 S12 > 13 s 5 5 0 12 4 3 0 8 S13 > 14 s 5 6 4 9 4 6 2 6 S14 > 15 s 14 5 12 3 12 3 11 3 S15 > 16 s 7 2 11 3 5 2 10 2 S16 > 17 s 1 7 4 5 1 6 3 5 S17 > 18 s 6 2 7 4 6 2 7 4 S18 > 19 s 9 4 8 5 10 4 6 3 S19 > 20 s 8 2 6 5 9 2 6 4 S20 > 21 s 6 5 5 7 6 6 5 5 S21 > 22 s 8 8 3 7 6 7 5 3 S22 > 23 s 11 4 6 7 1 1 6 4 S23 > 24 s 6 3 2 4 6 4 2 2 S24 > 25 s 4 4 6 6 2 3 4 6 S25 > 26 w 5 9 4 7 3 7 3 5 S26 > 27 w 7 6 3 5 4 1 0 4 S27 > 28 w 10 4 14 2 8 4 10 2 S28 > 29 w 9 7 5 6 8 4 5 3 S29 > 30 w 9 2 7 5 6 2 6 5 S30 > 31 w 6 7 6 7 6 5 5 8 S31 > 32 w 7 6 12 7 6 3 10 7 S32 > 33 w 12 3 8 9 11 3 4 7 S33 > 34 w 12 2 10 5 9 2 6 3 S34 > 35 w 6 3 10 4 5 3 5 3 S35 > 36 w 9 3 9 9 6 3 7 8 S36 > 37 w 5 11 7 7 4 11 3 4 S37 > 38 w 7 4 4 6 7 3 1 5 S38 > 39 w 6 5 1 8 3 3 0 8 S39 > 40 w 10 3 10 2 7 3 7 2 S40 > 41 w 1 11 7 5 1 8 4 3 S41 > 42 w 10 5 6 10 10 4 3 9 S42 > 43 w 6 3 9 2 4 2 6 0 S43 > 44 w 9 5 11 4 5 4 7 3 S44 > 45 w 8 5 6 3 8 4 2 3 S45 > 46 w 8 4 8 7 4 1 2 6 S46 > 47 w 12 2 6 2 10 1 5 2 S47 > 48 w 10 6 9 8 7 5 7 8 S48 > 49 w 13 6 15 1 12 4 14 0 S49 > 50 w 7 8 1 12 4 7 1 11 S50 > 51 w 12 3 9 4 9 1 7 4 S51 > > ______________________________________________ > R-help@r-project.org 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. > ______________________________________________ R-help@r-project.org 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.