| substr {base} | R Documentation |
Extract substrings from a character vector returning a
vector whose elements contain the substring starting with the
character at position start up to the character at position
stop.
substr(x, start, stop) substring(text, first, last = 1000000)
If start is larger than the string length then
NA is returned.
If stop is longer than start an error is signalled.
substring is compatible with S, with first and
last instead of start and stop.
For vector arguments, it expands the arguments cyclically.
substr("abcdef",2,4)
print(ss <- substring("abcdef",1:6,1:6))
stopifnot(ss == strsplit ("abcdef",NULL)[[1]])# strsplit is more efficient..
substr(rep("abcdef",4),1:4,4:5)
x <- c("asfef", "qwerty", "yuiop[", "b", "stuff.blah.yech")
stopifnot(substr(x, 2, 5) == substring(x, 2, 5))
substr(x, 2, 5)
substring(x, 2, 4:6)