Hello,
I'm having difficulty passing an object name to a lapply function. Can
somebody tell me the trick to make this work?
#Works
T13702 <- TRACKDATA[["13702.xls"]][["data"]]
min(unlist(lapply(list(T13702), function(x) mdy.date(x[1, 2], x[1, 1],
x[1, 3]))))
16553
#Works
d<-2
assign(paste("T",substr(names(TRACKDATA)[d],1,(nchar(names(TRACKDATA)[d]
)-4)),sep=""),TRACKDATA[[d]][["data"]],pos=1)
min(unlist(lapply(list(T13702), function(x) mdy.date(x[1, 2], x[1, 1],
x[1, 3]))))
16553
#Fails.
d<-2
assign(paste("T",substr(names(TRACKDATA)[d],1,(nchar(names(TRACKDATA)[d]
)-4)),sep=""),TRACKDATA[[d]][["data"]],pos=1)
min(unlist(lapply(list(paste("T",substr(names(TRACKDATA)[d],1,(nchar(nam
es(TRACKDATA)[d])-4)),sep="")), function(x) mdy.date(x[1, 2], x[1, 1],
x[1, 3]))))
Error in x[1, 2] : incorrect number of dimensions
> traceback()
4: mdy.date(x[1, 2], x[1, 1], x[1, 3])
3: FUN(X[[1L]], ...)
2: lapply(list(paste("T", substr(names(TRACKDATA)[d], 1,
(nchar(names(TRACKDATA)[d]) -
4)), sep = "")), function(x) mdy.date(x[1, 2], x[1, 1], x[1,
3]))
1: unlist(lapply(list(paste("T", substr(names(TRACKDATA)[d], 1,
(nchar(names(TRACKDATA)[d]) - 4)), sep = "")), function(x)
mdy.date(x[1,
2], x[1, 1], x[1, 3])))
#Fails (trying noquote).
min(unlist(lapply(list(noquote(paste("T",substr(names(TRACKDATA)[d],1,(n
char(names(TRACKDATA)[d])-4)),sep=""))), function(x) mdy.date(x[1, 2],
x[1, 1], x[1, 3]))))
Error in unclass(x)[...] : incorrect number of dimensions
> traceback()
6: `[.noquote`(x, 1, 2)
5: x[1, 2]
4: mdy.date(x[1, 2], x[1, 1], x[1, 3])
3: FUN(X[[1L]], ...)
2: lapply(list(noquote(paste("T", substr(names(TRACKDATA)[d], 1,
(nchar(names(TRACKDATA)[d]) - 4)), sep = ""))), function(x)
mdy.date(x[1,
2], x[1, 1], x[1, 3]))
1: unlist(lapply(list(noquote(paste("T", substr(names(TRACKDATA)[d],
1, (nchar(names(TRACKDATA)[d]) - 4)), sep = ""))), function(x)
mdy.date(x[1,
2], x[1, 1], x[1, 3])))
> Mark Fowler
Population Ecology Division
> Bedford Inst of Oceanography
> Dept Fisheries & Oceans
> Dartmouth NS Canada
B2Y 4A2
Tel. (902) 426-3529
Fax (902) 426-9710
Email fowl...@mar.dfo-mpo.gc.ca
Home Tel. (902) 461-0708
Home Email mark.fow...@ns.sympatico.ca
[[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.
