[R] applying strsplit to a whole column

[Dimitri Liakhovitski]

I am sorry, someone said that strsplit automatically works on a
column. How exactly does it work?
For example, if I want to grab just the first (or the second) part of
the string in nam1 that should be split based on ".."
x<-data.frame(nam1=c("bbb..aba","ccc..abb","ddd..abc","eee..abd"),
stringsAsFactors=FALSE)
str(x)
strsplit(x[[1]],split="\\..")
str(strsplit(x[[1]],split="\\.."))

I am getting a list - hence, it looks like I have to go in a loop...?

Thank you!
Dimitri


On Wed, Aug 4, 2010 at 2:39 PM, Dimitri Liakhovitski
<dimitri.liakhovitski at gmail.com> wrote:
> Thank you very much, everyone!
> Dimitri
>
> On Wed, Aug 4, 2010 at 2:10 PM, David Winsemius <dwinsemius at comcast.net> wrote:
>>
>> On Aug 4, 2010, at 1:42 PM, Dimitri Liakhovitski wrote:
>>
>>> I am sorry, I'd like to split my column ("names") such that all the
>>> beginning of a string ("X..") is gone and only the rest of the text is
>>> left.
>>
>> I could not tell whether it was the string "X.." or the pattern "X.." that
>> was your goal for matching and removal.
>>>
>>> x<-data.frame(names=c("X..aba","X..abb","X..abc","X..abd"))
>>> x$names<-as.character(x$names)
>>
>> a) Instead of "names" which is heavily used function name, use something
>> more specific. Otherwise you get:
>>> names(x)
>> "names"  # and thereby avoid list comments about canines.
>>
>> b) Instead of coercing a character vector back to a character vector, use
>> stringsAsFactors = FALSE.
>>
>>> x<-data.frame(nam1=c("X..aba","X..abb","X..abc","X..abd"),
>>> stringsAsFactors=FALSE)
>> #Thus is the pattern version:
>>
>>> x$nam1 <- gsub("X..",'', x$nam1)
>>> x
>>  nam1
>> 1   aba
>> 2   abb
>> 3   abc
>> 4   abd
>>
>> This is the string version:
>>> x<-data.frame(nam1=c("X......aba","X.y.abb","X..abc","X..abd"),
>>> stringsAsFactors=FALSE)
>>>  x$nam1 <- gsub("X\\.+",'', x$nam1)
>>> x
>>   nam1
>> 1   aba
>> 2 y.abb
>> 3   abc
>> 4   abd
>>
>>
>>> (x)
>>> str(x)
>>>
>>> Can't figure out how to apply strsplit in this situation - without
>>> using a loop. I hope it's possible to do it without a loop - is it?
>>
>> --
>>
>> David Winsemius, MD
>> West Hartford, CT
>>
>>
>
>
>
> --
> Dimitri Liakhovitski
> Ninah Consulting
> www.ninah.com
>



-- 
Dimitri Liakhovitski
Ninah Consulting
www.ninah.com