Converting characters to numbers in data frames
Anon. wrote:
I'm sure I'm missing something obvious here, but I can't find the
solution (including in the FAQ etc.).
I have a vector of names of variables like this: NRes.x.y. where x and y
are numbers. I want to extract these numbers as numbers to use
elsewhere. I can extract the numbers as a list of characters using
strsplit(), and convert that to a data frame, e.g.:
NAMES=c("NRes.1.2.", "NRes.1.3.", "NRes.1.4.", "NRes.1.5.", "NRes.1.6.")
NUMBERS=strsplit(gsub("NRes.","", NAMES, perl =T), '.', fixed = TRUE)
NUMBERS.df=t(data.frame(NUMBERS))
But I now want to convert the characters to be numeric. Using
as.numeric(NUMBERS.df) converts them, but to a vector. How can I
convert and keep as a data frame? I could use this:
matrix(as.numeric(NUMBERS.df), ncol=dim(NUMBERS.df)[2])
but I seem to be jumping through far too many hoops: there must be an
easier way. An suggestions?
Bob
How about this?
NUMBERS <- lapply(strsplit(NAMES, "\\."), "[", -1)
as.data.frame(do.call("rbind", lapply(NUMBERS, as.numeric)))
--sundar