Have you changed the values in b.df? My reading of the original b.df in Erin's post was that there were no common values in PATIENT_ID and ID.
--- On Tue, 6/29/10, jim holtman <jholt...@gmail.com> wrote: > From: jim holtman <jholt...@gmail.com> > Subject: Re: [R] merging/intersecting 2 data frames > To: "Erin Hodgess" <erinm.hodg...@gmail.com> > Cc: "R help" <r-h...@stat.math.ethz.ch> > Received: Tuesday, June 29, 2010, 3:31 PM > use 'merge' > > > a.df > DATE GENDER PATIENT_ID > AGE > SYNDROME > 1 4/16/2009 F > 23686 45 RASH ON > BODY > 2 4/16/2009 F > 13840 35 CANT > URINATE > 3 4/16/2009 M > 12895 30 BLURRED > VISION > 4 4/16/2009 M > 18375 33 UNABLE TO > VOID > 5 4/16/2009 M > 2237 44 > SOB WEAKNESS > 6 4/16/2009 F > 21484 41 TOOTH PAINTOOTH PAIN > 7 4/16/2009 M > 10783 37 RT ARM > PAIN > 8 4/16/2009 M > 12610 65 L FOOT INJURY > 9 4/16/2009 F > 3495 29 URINARY DIFFICULTIES > 10 4/16/2009 F > 351 36 > PT STS MVA > > b.df > DATE_OF_DEATH ID > 1 4/19/2009 23686 > 2 4/19/2009 13840 > 3 4/19/2009 12895 > 4 4/19/2009 18375 > 5 4/19/2009 351 > 6 4/20/2009 3495 > 7 4/20/2009 4084 > 8 4/20/2009 19616 > 9 4/20/2009 17965 > 10 4/20/2009 11863 > > merge(a.df, b.df, by.x="PATIENT_ID", by.y="ID") > PATIENT_ID DATE GENDER AGE > SYNDROME > DATE_OF_DEATH > 1 351 4/16/2009 > F 36 > PT STS MVA > 4/19/2009 > 2 3495 4/16/2009 > F 29 URINARY DIFFICULTIES > 4/20/2009 > 3 12895 4/16/2009 > M 30 BLURRED > VISION 4/19/2009 > 4 13840 4/16/2009 > F 35 CANT > URINATE 4/19/2009 > 5 18375 4/16/2009 > M 33 UNABLE TO > VOID 4/19/2009 > 6 23686 4/16/2009 > F 45 RASH ON > BODY 4/19/2009 > > > > > On Tue, Jun 29, 2010 at 3:21 PM, Erin Hodgess <erinm.hodg...@gmail.com> > wrote: > > Dear R People: > > > > I have two data frames, a.df and b.df as seen here: > > > >> a.df[1:10,] > > DATE GENDER PATIENT_ID AGE > SYNDROME > > 1 4/16/2009 F 23686 45 > RASH ON BODY > > 2 4/16/2009 F 13840 35 > CANT URINATE > > 3 4/16/2009 M 12895 30 > BLURRED VISION > > 4 4/16/2009 M 18375 33 > UNABLE TO VOID > > 5 4/16/2009 M 2237 44 > SOB WEAKNESS > > 6 4/16/2009 F 21484 41 TOOTH > PAINTOOTH PAIN > > 7 4/16/2009 M 10783 37 > RT ARM PAIN > > 8 4/16/2009 M 12610 65 > L FOOT INJURY > > 9 4/16/2009 F 3495 29 URINARY > DIFFICULTIES > > 10 4/16/2009 F 351 36 > PT STS MVA > >> b.df[1:10,] > > DATE_OF_DEATH ID > > 1 4/19/2009 21676 > > 2 4/19/2009 13717 > > 3 4/19/2009 20498 > > 4 4/19/2009 14281 > > 5 4/19/2009 38848 > > 6 4/20/2009 331 > > 7 4/20/2009 4084 > > 8 4/20/2009 19616 > > 9 4/20/2009 17965 > > 10 4/20/2009 11863 > >> > > > > a.df will always be larger than b.df. > > > > I want to create a third data frame that is matched on > PATIENT_ID from > > a.df and ID from b.df. > > > > If there is no match from a.df$PATIENT_ID to b.df$ID, > then we omit the > > row from the new data.frame. > > > > If there is a match, we include the DATE_OF_DEATH > column from b.df. > > > > I've tried all kinds of tricks, but nothing works > exactly as I wish. > > > > Thanks in advance, > > Sincerely, > > Erin > > > > > > -- > > Erin Hodgess > > Associate Professor > > Department of Computer and Mathematical Sciences > > University of Houston - Downtown > > mailto: erinm.hodg...@gmail.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. > ______________________________________________ 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.
