[R] overlapping pattern match

[FMGCFMGC]

try with this:

your.string <- "aaacdf"
nc1 <- nchar(your.string)-1
x <- unlist(strsplit(cadena, NULL)) 
x2 <- c()
for (i in 1:nc1)
  x2 <- c(x2, paste(x2[i], x2[i+1], sep=""))
cat("ocurrences of <aa> in <your.string>:", length(grep("aa", x2)),
  sep="", fill=TRUE)

Hope it helps!
Fran

--- original message ---
Hi, all,
     I have a string like  "aaacdf",  I want to find how many "aa" in 
the string. Obviously, It is 2 in this case.  it is easy to do in Perl, 
but how to do such  overlapping match in R or Splus.  Thanks!

Y.Fan