Re: [R] Extracting first number after * in a character vector
Elegant I don't know, but I think the appended does the trick.
-- Mike
> foo <- c(" 1 X[0,SMITH] * 0 0 1 ",
+ " 2 X[0,JOHNSON] * 0 0 1 ",
+ " 3 X[0,WILLIAMS] * 1 0 1 ",
+ " 4 X[0,JONES] * 0 0 1 ",
+ [TRUNCATED]
> as.numeric(gsub("^[^*]+[*][^0-9]+([01]).*$", "\\1", foo))
[1] 0 0 1 0 0 0 0 0 0
>
On Mon, Jan 23, 2017 at 1:27 PM, Jim Lemon wrote:
> Hi Abhinaba,
> I'm sure that someone will post a terrifyingly elegant regular
> expression that does this, but:
>
> ardat<-
> c([1] " 1 X[0,SMITH] * 0 0 1 ",
> ...
> numpoststar<-function(x) {
> xsplit<-unlist(strsplit(x,""))
> starpos<-which(xsplit=="*")
> # watch out for a missing asterisk, they cause an infinite loop
> if(length(starpos)) {
> digits<-c("0","1","2","3","4","5","6","7","8","9")
> while(!any(digits %in% xsplit[starpos])) starpos<-starpos+1
> return(as.numeric(xsplit[starpos]))
> }
> return(NA)
> }
>
> for(i in 1:length(ardat)) print(numpoststar(ardat[i]))
>
> The observant will wonder why I didn't use sapply. Because for some
> reason it returned the original strings rather than the numbers. I
> dunno.
>
> Jim
>
> On Mon, Jan 23, 2017 at 11:29 PM, Abhinaba Roy
> wrote:
>> Hi,
>>
>> How do I extract the first number after '*' in a vector?
>>
>> The vector is given below
>>
>>> dput(out[1:10])
>> c(" 1 X[0,SMITH] * 0 0 1 ",
>> " 2 X[0,JOHNSON] * 0 0 1 ",
>> " 3 X[0,WILLIAMS]", "* 1 0
>> 1 ",
>> " 4 X[0,JONES] * 0 0 1 ",
>> " 5 X[0,BROWN] * 0 0 1 ",
>> " 6 X[0,DAVIS] * 0 0 1 ",
>> " 7 X[0,MILLER] * 0 0 1 ",
>> " 8 X[0,WILSON] * 0 0 1 ",
>> " 9 X[0,MOORE] * 0 0 1 "
>> )
>>
>> I want a vector with the first number after the asterisk.
>>
>> So the output would give me, a vector (0,0,1,0,0,0,0,0,0,0)
>>
>> How can I do it in R?
>>
>> Best,
>> Abhinaba
>>
>> [[alternative HTML version deleted]]
>>
>> __
>> R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see
>> 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.
>
> __
> R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see
> 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.
__
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Re: [R] Extracting first number after * in a character vector
Hi Abhinaba,
I'm sure that someone will post a terrifyingly elegant regular
expression that does this, but:
ardat<-
c([1] " 1 X[0,SMITH] * 0 0 1 ",
...
numpoststar<-function(x) {
xsplit<-unlist(strsplit(x,""))
starpos<-which(xsplit=="*")
# watch out for a missing asterisk, they cause an infinite loop
if(length(starpos)) {
digits<-c("0","1","2","3","4","5","6","7","8","9")
while(!any(digits %in% xsplit[starpos])) starpos<-starpos+1
return(as.numeric(xsplit[starpos]))
}
return(NA)
}
for(i in 1:length(ardat)) print(numpoststar(ardat[i]))
The observant will wonder why I didn't use sapply. Because for some
reason it returned the original strings rather than the numbers. I
dunno.
Jim
On Mon, Jan 23, 2017 at 11:29 PM, Abhinaba Roy wrote:
> Hi,
>
> How do I extract the first number after '*' in a vector?
>
> The vector is given below
>
>> dput(out[1:10])
> c(" 1 X[0,SMITH] * 0 0 1 ",
> " 2 X[0,JOHNSON] * 0 0 1 ",
> " 3 X[0,WILLIAMS]", "* 1 0
> 1 ",
> " 4 X[0,JONES] * 0 0 1 ",
> " 5 X[0,BROWN] * 0 0 1 ",
> " 6 X[0,DAVIS] * 0 0 1 ",
> " 7 X[0,MILLER] * 0 0 1 ",
> " 8 X[0,WILSON] * 0 0 1 ",
> " 9 X[0,MOORE] * 0 0 1 "
> )
>
> I want a vector with the first number after the asterisk.
>
> So the output would give me, a vector (0,0,1,0,0,0,0,0,0,0)
>
> How can I do it in R?
>
> Best,
> Abhinaba
>
> [[alternative HTML version deleted]]
>
> __
> R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see
> 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.
__
R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see
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.
Re: [R] Extracting first number after * in a character vector
On 23.01.2017 13:29, Abhinaba Roy wrote:
Hi,
How do I extract the first number after '*' in a vector?
The vector is given below
dput(out[1:10])
c(" 1 X[0,SMITH] * 0 0 1 ",
" 2 X[0,JOHNSON] * 0 0 1 ",
" 3 X[0,WILLIAMS]", "* 1 0
1 ",
" 4 X[0,JONES] * 0 0 1 ",
" 5 X[0,BROWN] * 0 0 1 ",
" 6 X[0,DAVIS] * 0 0 1 ",
" 7 X[0,MILLER] * 0 0 1 ",
" 8 X[0,WILSON] * 0 0 1 ",
" 9 X[0,MOORE] * 0 0 1 "
)
I want a vector with the first number after the asterisk.
So the output would give me, a vector (0,0,1,0,0,0,0,0,0,0)
How can I do it in R?
You know that your vector (called x below) contains an element without
an asterisk?
If that happened by accident, use
gsub(".+\\* *([[:digit:]]+).*", "\\1", x)
and if it could happen to have elements without an asterisk or number
that follows, you can set these results to NA in a seperate step.
Best,
Uwe Ligges
Best,
Abhinaba
[[alternative HTML version deleted]]
__
R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see
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PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
__
R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see
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.
