problem with pattern matching
the problem in my case is that some of the cells in dataframe$ID contain multiple IDs, but in list$ID there is only one ID in each cell, so some of the IDs cannot be matched if using the fucntion 'match' or '%in%'
jholtman wrote:
I think you want to use either 'match' or '%in%' x <- dataframe$ID %in% list$ID # TRUE if it is in list On Wed, Aug 5, 2009 at 5:36 AM, Rnewbie<xuancj at yahoo.com> wrote:
I wanted to extract my interested rows from a dataframe. I used: grep(list$ID, dataframe$ID, value=T) #list contains a list of my interested IDs I got one match in return, which is the very first ID in list. It seems the matching process just stopped, once the first match was found. David Winsemius wrote:
On Aug 4, 2009, at 11:16 AM, Rnewbie wrote:
dear all, I got a problem with pattern matching using grep. I extracted a list of characters from a data frame, and I tried to match this list of characters to a column from another data frame. In return, I got only one match, but there should be far more matches. Any ideas what has gone wrong?
In general this falls into the category of ?a request to "read my mind". One, out of probably an infinite number, of ways to get such a result is to use if() ?when you needed ifelse().
Another question, if I also want to match the whole of the elements against the non-initial parts of the elements in another table. Which command should I use?
Cannot even assign a semantic meaning to that one. What is are "non- initial parts of the elements of another table"? ******************************************************************
?.... provide commented, minimal, self-contained, reproducible code.
******************************************************************
Thanks
David Winsemius, MD Heritage Laboratories West Hartford, CT
______________________________________________ R-help at r-project.org mailing list 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.
-- View this message in context: http://www.nabble.com/problem-with-pattern-matching-tp24810298p24823683.html Sent from the R help mailing list archive at Nabble.com.
______________________________________________ R-help at r-project.org mailing list 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.
-- Jim Holtman Cincinnati, OH +1 513 646 9390 What is the problem that you are trying to solve?
______________________________________________ R-help at r-project.org mailing list 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.
View this message in context: http://www.nabble.com/problem-with-pattern-matching-tp24810298p24826143.html Sent from the R help mailing list archive at Nabble.com.