[R] Split string

[Gabor Grothendieck]

On Thu, Apr 16, 2009 at 2:01 PM, Peter Dalgaard
<p.dalgaard at biostat.ku.dk> wrote:
> Gabor Grothendieck wrote:
>>
>> Using string from another responder's post here are two
>> solutions:
>>
>
> Er, a rather more obvious solution could be to point to the definition of
> substr...

Only if there are a fixed number of digits.

>
>> 1. The first converts to numeric and manipulates that:
>
> [snip]
>>>
>>> [37] "0.30" "  NA" "0.30" "0.30" "0.30" "0.30" "  NA" "  NA" "0.35"
>>> "NA" "0.35" "0.30"
>>> [49] "0.30" "0.40" "  NA" "0.40" "0.30" "  NA" "0.30" "0.30" "0.30"
>>> "0.30" "0.45" "0.30"
>>> [61] "0.30" "0.30" "0.30" "0.50" "0.30" "0.30" "0.45" "0.30"
>>>
>>> How do I output the number to the left of "." to variable X and the
>>> two numbers to the right of "." to variable Y?
>>>
>>> FICB[,"x"] <- substr(FICB[,"temp2"],1,1)
>>> Works, but
>>>
>>> FICB[,"y"] <- substr(FICB[,"temp2"],3,2)
>>> only returns "". temp is class character.
>
> That will happen when stop < start, try "...,3,4)"!
>
> Alternatively sub("^[0-9]*\\.", "", ...) and sub("\\.[0-9]*$", "", ...)
> should do the trick slightly more generally.
>
>> sub("^[0-9]*\\.", "", "0.30")
> [1] "30"
>> sub("\\.[0-9]*$", "", "0.30")
> [1] "0"
>
> (and in either case, don't forget to get rid of the ".*NA.*" elements)
>
> --
>   O__  ---- Peter Dalgaard             Øster Farimagsgade 5, Entr.B
>  c/ /'_ --- Dept. of Biostatistics     PO Box 2099, 1014 Cph. K
>  (*) \(*) -- University of Copenhagen   Denmark      Ph:  (+45) 35327918
> ~~~~~~~~~~ - (p.dalgaard at biostat.ku.dk)              FAX: (+45) 35327907
>