andilabs
8/30/2013 - 1:01 AM

MERGE-ing (pasting) two data frames in R: all=FALSE if you want INTERSECTION (common part of both) as a result all=TRUE if you want SU

MERGE-ing (pasting) two data frames in R:

all=FALSE if you want INTERSECTION (common part of both) as a result

all=TRUE if you want SUM (differences fullfiled with NA) as a result

http://stat.ethz.ch/R-manual/R-devel/library/base/html/merge.html

gistfile1.r
content_copyfile_download
> authors
   surname nationality deceased
1    Tukey          US      yes
2 Venables   Australia       no
3  Tierney          US       no
4   Ripley          UK       no
5   McNeil   Australia       no
> books
      name                         title     other.author
1    Tukey     Exploratory Data Analysis             <NA>
2 Venables Modern Applied Statistics ...           Ripley
3  Tierney                     LISP-STAT             <NA>
4   Ripley            Spatial Statistics             <NA>
5   Ripley         Stochastic Simulation             <NA>
6   McNeil     Interactive Data Analysis             <NA>
7   R Core          An Introduction to R Venables & Smith
> authors_books<-merge(authors,books,by.x="surname",by.y="name",all=TRUE)
> authors_books
   surname nationality deceased                         title     other.author
1   McNeil   Australia       no     Interactive Data Analysis             <NA>
2   R Core        <NA>     <NA>          An Introduction to R Venables & Smith
3   Ripley          UK       no            Spatial Statistics             <NA>
4   Ripley          UK       no         Stochastic Simulation             <NA>
5  Tierney          US       no                     LISP-STAT             <NA>
6    Tukey          US      yes     Exploratory Data Analysis             <NA>
7 Venables   Australia       no Modern Applied Statistics ...           Ripley
> authors_books<-merge(authors,books,by.x="surname",by.y="name",all=FALSE)
> authors_books
   surname nationality deceased                         title other.author
1   McNeil   Australia       no     Interactive Data Analysis         <NA>
2   Ripley          UK       no            Spatial Statistics         <NA>
3   Ripley          UK       no         Stochastic Simulation         <NA>
4  Tierney          US       no                     LISP-STAT         <NA>
5    Tukey          US      yes     Exploratory Data Analysis         <NA>
6 Venables   Australia       no Modern Applied Statistics ...       Ripley