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<xua...@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@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@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@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. ______________________________________________ R-help@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.
