On 11/02/2012 11:38 AM, wang peter wrote: > thank u for your advice > i really donot know how to pick up the first element > > i only know > sapply(x,unlist) > This is the only way you know how to use sapply? So I wonder who wrote this code you sent the other day? https://stat.ethz.ch/pipermail/bioconductor/2012-October/048914.html It's using sapply in a way that is much more elaborated than sapply(x,unlist). I sent you my advice to do some homework at 11:27am, and at 11:38am you come back saying that sapply(x,unlist) is the only thing you know. Sorry but I'm afraid you'll need to do more than 11 minutes of homework in order to have a chance to make any progress *by yourself*. Cheers, H. -- Hervé Pagès Program in Computational Biology Division of Public Health Sciences Fred Hutchinson Cancer Research Center 1100 Fairview Ave. N, M1-B514 P.O. Box 19024 Seattle, WA 98109-1024 E-mail: hpages at fhcrc.org Phone: (206) 667-5791 Fax: (206) 667-1319

thank u very much you really helped me a lot. but those coding is from another people. now i imiate those coding,wirte such coding but it cannot work match_positions <- sapply(1:length(match_positions), function(j) {unlist(match_positions(j))[1]});