# Select a set of rows based on a condition

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## Select a set of rows based on a condition

 Hi, I need help with selecting a set of rows from a column in a dataset, that matches a string criteria - start and end. The dataset is :       List|Index           10    ABC                  20    DEF                   10    GHI                   50    JKL                    40    MNO                  20    PQR                   10     Start="DEF" End = "MNO" Ideally, I would like to select the data from DEF to MNO into a new data set. My logic is 1) get the row number for DEF 2) get the row number for MNO 3) subset the rows from DEF to MNO Can someone please help me with the R code for this as am a little rusty. Please let me know if you have questions. Thanks in advance! Raoul
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## Re: Select a set of rows based on a condition

 If you know the index letters are unique. df <- data.frame(indx = LETTERS[1:7], levels = sample(7)) ind1 <- which(df\$indx == "A") ind2 <- which(df\$indx == "B") df[ind1:ind2, ] Michael On Wed, Dec 7, 2011 at 6:23 AM, RaoulD <[hidden email]> wrote: > Hi, > > I need help with selecting a set of rows from a column in a dataset, that > matches a string criteria - start and end. The dataset is : > >   >   List|Index           10 >   ABC                  20 >   DEF                   10 >   GHI                   50 >   JKL                    40 >   MNO                  20 >   PQR                   10 > > Start="DEF" > End = "MNO" > > Ideally, I would like to select the data from DEF to MNO into a new data > set. My logic is > 1) get the row number for DEF > 2) get the row number for MNO > 3) subset the rows from DEF to MNO > > Can someone please help me with the R code for this as am a little rusty. > Please let me know if you have questions. > > Thanks in advance! > Raoul > > -- > View this message in context: http://r.789695.n4.nabble.com/Select-a-set-of-rows-based-on-a-condition-tp4168594p4168594.html> Sent from the R help mailing list archive at Nabble.com. > > ______________________________________________ > [hidden email] 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. ______________________________________________ [hidden email] mailing list https://stat.ethz.ch/mailman/listinfo/r-helpPLEASE do read the posting guide http://www.R-project.org/posting-guide.htmland provide commented, minimal, self-contained, reproducible code.