[R] Convert char vector to numeric table

Nurnberg-LaZerte mail at fwr.on.ca
Tue Apr 1 00:09:42 CEST 2003


I'm a great fan of read.table(), but this time the data had a lot of cruft. So I used readLines() and editted the char vector to eventually get something like this:
"     23.4   1.5   4.2"
"     19.1   2.2   4.1"
and so on. To get that into a 3 col numeric table, I first just used:

writeLines(data,"tempfile")
read.table("tempfile",col.names=c("A","B","C"))

Works fine, but writing to a temporary file seems ... inelegant?  And read.table() doesn't take a char vector as a file or connection argument. The following works but it seems like a lot of code: 

data <- sub(" +","",data)   		# remove leading blanks for strsplit
data <- strsplit(data," +")   		# strsplit returns a list of char vectors
ndata <- character(0)			# vectorize the list of char vectors
for (ii in 1:length(data)) ndata <- c(ndata,data[[ii]])  
ndata <- as.numeric(ndata)				
dim(ndata) <- c(3,length(data))	  	
data <- t(ndata)
data.frame(A=data[,1],B=data[,2],C=data[,3])

Am I missing something?

Thanks,
Bruce L.



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