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[Bioc-devel] BStringSet Documentation

4 messages · Dario Strbenac, Hervé Pagès

Original
Dario Strbenac
# 
Good day,

According to the documentation, I wouldn't think that substr or strsplit would work on a BStringSet, but substr does.
A BStringSet instance of length 5
    width seq
[1]    61 D00626:168:C9CWMANXX:1:1105:1816:1998 1:N:0:TCCGGAGA+ATAGAGGC
[2]    61 D00626:168:C9CWMANXX:1:1105:2113:1989 1:N:0:TCCGGAGA+ATAGAGGC
[3]    61 D00626:168:C9CWMANXX:1:1105:2703:1986 1:N:0:TCCGGAGA+ATAGAGGC
[4]    61 D00626:168:C9CWMANXX:1:1105:3255:1979 1:N:0:TCCGGAGA+ATAGAGGC
[5]    61 D00626:168:C9CWMANXX:1:1105:4525:1995 1:N:0:TCCGGAGA+ATAGAGGC
[1] "D00626:168:C9CWMANXX:1:1105:1816:1998"
[2] "D00626:168:C9CWMANXX:1:1105:2113:1989"
[3] "D00626:168:C9CWMANXX:1:1105:2703:1986"
[4] "D00626:168:C9CWMANXX:1:1105:3255:1979"
[5] "D00626:168:C9CWMANXX:1:1105:4525:1995"
Error in strsplit(IDs, " ") : non-character argument

I think that both of these functions shouldn't work or both should work, to be consistent.

--------------------------------------
Dario Strbenac
University of Sydney
Camperdown NSW 2050
Australia
1 day later
Hervé Pagès
# 
Hi,
On 09/01/2016 12:00 AM, Dario Strbenac wrote:
Why? Because they both have "str" in their name?

It sounds that you are expecting that every string manipulation function
defined in base R should work on a BStringSet object. Well that's not
the case and I don't think that's ever going to happen. Some of them
work and some of them don't. We can add more if needed (e.g. strsplit)
but there are things like the grep family that BStringSet objects will
probably never support.

If you need to strsplit() an XStringSet object, you can use this:

   strsplitXStringSet <- function(x, split)
   {
       m <- vmatchPattern(split, x)
       at <- gaps(IRangesList(start=start(m),
                  end=end(m)), start=1L, end=width(x))
       extractAt(x, at)
   }

It's going to behave like strsplit(x, split, fixed=TRUE) except when
there is a match at the beginning or end of one of the sequences (in
which case strsplit() has a questionable behavior). Also, unlike
strsplit(), strsplitXStringSet() doesn't support an empty split
pattern.

Note that BStringSet objects have supported the reverse operation
for a while. See ?unstrsplit

I'll add strsplitXStringSet() to Biostrings, as the "strsplit" method
for XStringSet objects.

H.

  
    

      
      
    

  


  


      

    

    

      
      

        


  

        

      Hervé Pagès
    

    

      
      #
    

  


  

      
On 09/02/2016 12:25 PM, Herv? Pag?s wrote:

            

      
      
      
    

        
Another difference between strsplit() and strsplitXStringSet() is when
some matches are adjacent or overlapping. This will be explained in the
man page of strsplit,XStringSet-method.

H.

            

      
      
      
    

        

      
      
    

            

      
      
      
    

        

  
    

      
      
    

  


  


      

    

    

      
      

        


  

        

      Dario Strbenac
    

    

      
      #
    

  


  

      
Hello,

Actually, I thought that substr unintentionally worked and perhaps they should both produce an error message. Thanks for adding the functionality for strsplit, though!

--------------------------------------
Dario Strbenac
University of Sydney
Camperdown NSW 2050
Australia