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
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