Dear R-Helpers, I have a data.frame (df) and the head of data.frame looks like
ProbeUID ControlType ProbeName GeneName SystematicName 1665 1577 0 pSysX_50_22_1 pSysX_50 pSysX_50 5422 5147 0 pSysX_49_8_1 pSysX_49 pSysX_49 4042 3843 0 pSysX_51_18_1 pSysX_51 pSysX_51 3646 3466 0 sll1514_0_2 sll1514 sll1514 2946 2807 0 sll1514_0_1 sll1514 sll1514 624 582 0 pSysX_49_8_2 pSysX_49 pSysX_49 Description logFC AveExpr t P.Value adj.P.Val 1665 Unknown 4.3887 9.5662 61.038 1.0938e-08 9.4449e-05 5422 Unknown -3.5251 6.9103 -35.908 1.7596e-07 3.5912e-04 4042 Unknown 2.5302 8.7497 35.112 1.9786e-07 3.5912e-04 3646 Unknown 2.3457 11.1678 33.962 2.3549e-07 3.5912e-04 2946 Unknown 2.3151 11.3153 32.689 2.8751e-07 3.5912e-04 624 Unknown -3.6256 6.8986 -31.777 3.3333e-07 3.5912e-04 B 1665 9.8342 5422 8.1650 4042 8.0758 3646 7.9408 2946 7.7822 624 7.6622 I want to "collapse" this data frame into a new data.frame so that the df$GeneName contains no duplicate GeneNames (for eg: sll1514) AND the df$logFC contains the average of df$logFC corresponding to these GeneNames (which had duplicate genenames). I am aware of an inefficient strategy using loops, but I believe that there should be a way using Apply functions or may be plyr? I am not able to think of one at the moment. Can you please help me? Any help is appreciated ! Thanks and Best Regards, S. [[alternative HTML version deleted]] ______________________________________________ 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.