R help - May 2010 - regex help: splitting strings with no separator

Greetings,

I have a vector of values that are a word followed by a number, e.g., x
c("Apple12","HP42","Dell91").  The goal is to
split this vector into two
vectors such that the first vector contains just the words and the second
contains just the numbers.  I cannot use strsplit (or at least I do not know
how) as there is no obvious separator.

I can use sub to create a separator, e.g., y =
sub("([[:digit:]])","
\\1",x), and then use strsplit, but I thought more experienced R users may
have a better solution.  I've spent some time with Google, but not turned up
anything so far.

Many thanks,
--Krishna

	[[alternative HTML version deleted]]

Hi Krishna,

Here is a suggestion:
> x <- c("Apple12","HP42","Dell91")
> foo <- function(x) data.frame(brand = gsub("[0-9]",
"", x), number gsub("[^0-9]", "", x))
> foo(x)
# brand number
# 1 Apple     12
# 2    HP     42
# 3  Dell     91

HTH,
Jorge


On Wed, May 19, 2010 at 8:15 PM, Krishna Tateneni <> wrote:
> Greetings,
>
> I have a vector of values that are a word followed by a number, e.g., x
> c("Apple12","HP42","Dell91").  The goal is to
split this vector into two
> vectors such that the first vector contains just the words and the second
> contains just the numbers.  I cannot use strsplit (or at least I do not
> know
> how) as there is no obvious separator.
>
> I can use sub to create a separator, e.g., y =
sub("([[:digit:]])","
> \\1",x), and then use strsplit, but I thought more experienced R users
may
> have a better solution.  I've spent some time with Google, but not
turned
> up
> anything so far.
>
> Many thanks,
> --Krishna
>
>        [[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.
>
	[[alternative HTML version deleted]]

Try this:

read.table(textConnection(gsub("([[:alpha:]])(\\d.*)",
"\\1;\\2", x)), sep ";")

or

do.call(rbind, strsplit(gsub("([[:alpha:]])(\\d.*)",
"\\1;\\2", x), ";"))

On Wed, May 19, 2010 at 9:15 PM, Krishna Tateneni
<tateneni@gmail.com>wrote:
> Greetings,
>
> I have a vector of values that are a word followed by a number, e.g., x
> c("Apple12","HP42","Dell91").  The goal is to
split this vector into two
> vectors such that the first vector contains just the words and the second
> contains just the numbers.  I cannot use strsplit (or at least I do not
> know
> how) as there is no obvious separator.
>
> I can use sub to create a separator, e.g., y =
sub("([[:digit:]])","
> \\1",x), and then use strsplit, but I thought more experienced R users
may
> have a better solution.  I've spent some time with Google, but not
turned
> up
> anything so far.
>
> Many thanks,
> --Krishna
>
>        [[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.
>


-- 
Henrique Dallazuanna
Curitiba-Paraná-Brasil
25° 25' 40" S 49° 16' 22" O

	[[alternative HTML version deleted]]

One way is to use strapply in the gsubfn package.  It is like apply in
that the first argument is the object (in both cases), the second is
the modifier (the margin in the case of apply and the regular
expression in the case of strapply) and a function (in both cases).
The parenthesized expressions in the regular expression are captured
and passed to the function.  Here \\D+ is a string of non-digits and
\\d+ is a string of digits.  See http://gsubfn.googlecode.com home
page, the vignette and the help for more info.
> library(gsubfn)
> strapply(x, "(\\D+)(\\d+)", c, simplify = rbind)
     [,1]    [,2]
[1,] "Apple" "12"
[2,] "HP"    "42"
[3,] "Dell"  "91"


On Wed, May 19, 2010 at 8:15 PM, Krishna Tateneni <tateneni at gmail.com>
wrote:
> Greetings,
>
> I have a vector of values that are a word followed by a number, e.g., x
> c("Apple12","HP42","Dell91"). ?The goal is to
split this vector into two
> vectors such that the first vector contains just the words and the second
> contains just the numbers. ?I cannot use strsplit (or at least I do not
know
> how) as there is no obvious separator.
>
> I can use sub to create a separator, e.g., y =
sub("([[:digit:]])","
> \\1",x), and then use strsplit, but I thought more experienced R users
may
> have a better solution. ?I've spent some time with Google, but not
turned up
> anything so far.
>
> Many thanks,
> --Krishna
>
> ? ? ? ?[[alternative HTML version deleted]]
>
> ______________________________________________
> R-help at 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.
>