Hon Kit (Stephen) Wong
2013-May-20 23:45 UTC
[R] how to GREP out a string like this......THANKS.
Dear ALl, I hope you could help me out on this simple problem. I have many thousand lines like this: NM_019397 // Egfl6 // EGF-like-domain, multiple 6 // X F5|X 71.5 cM // 54156 I want to extract the string inside the first // //, in this case is Egf16. How do I apply grep function? Thanks. Stephen HK Wong Stephen HK Wong Research Associate,Cleary Lab Lab Phone: 650-723-5340 MC 5457 Lokey Stem Cell Research Building 265 Campus Drive, Rm. G2035 Stanford, California 94305-5324
On May 20, 2013, at 4:45 PM, Hon Kit (Stephen) Wong wrote:> Dear ALl, > > I hope you could help me out on this simple problem. I have many thousand lines like this: > NM_019397 // Egfl6 // EGF-like-domain, multiple 6 // X F5|X 71.5 cM // 54156 > > I want to extract the string inside the first // //, in this case is Egf16.> strsplit("NM_019397 // Egfl6 // EGF-like-domain, multiple 6 // X F5|X 71.5 cM // 54156", split=" // ")[[1]][2][1] "Egfl6" You can use; lapply( lines, function(l) strsplit(l, " // ")[[1]][2] )> > > How do I apply grep function?Well, grep is only going to give you a test and you want a replacement or extraction function. sub or gsub would be possibilities but they are greedy so its a bit more difficult to constrain their targeting to only the first and second "//". -- David Winsemius Alameda, CA, USA
Hi,
May be this helps.
lines<- readLines(textConnection("NM_019397 // Egfl6 // EGF-like-domain,
multiple 6 // X F5|X 71.5 cM // 54156
NM_019397 // Egfl7 // EGF-like-domain, multiple 6 // X F5|X 71.5 cM //
54158"))
library(stringr)
word(lines,2,sep=" // ")
#[1] "Egfl6" "Egfl7"
lines1<- readLines(textConnection("NM_019397 // Egfl6 //
EGF-like-domain, multiple 6 // X F5|X 71.5 cM // 54156
NM_019397 // Egfl7 domain // EGF-like-domain, multiple 6 // X F5|X 71.5 cM //
54158"))
?word(lines1,2,sep=" // ")
#[1] "Egfl6"??????? "Egfl7 domain"
A.K.
----- Original Message -----
From: Hon Kit (Stephen) Wong <honkit at stanford.edu>
To: r-help at r-project.org
Cc:
Sent: Monday, May 20, 2013 7:45 PM
Subject: [R] how to GREP out a string like this......THANKS.
Dear ALl,
I hope you could help me out on this simple problem. I have many thousand lines
like this:
NM_019397 // Egfl6 // EGF-like-domain, multiple 6 // X F5|X 71.5 cM // 54156
I want to extract the string inside the first // //, in this case is Egf16.
How do I apply grep function?
Thanks.
Stephen HK Wong
Stephen HK Wong
Research Associate,Cleary Lab
Lab Phone: 650-723-5340
MC 5457
Lokey Stem Cell Research Building
265 Campus Drive, Rm. G2035
Stanford, California 94305-5324
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