[R] R command to join data.frames rows with identical keys?

[Titus von der Malsburg]

Have a look at the merge function.

  "Merge two data frames by common columns or row names, or do other
     versions of database _join_ operations."


  Titus

On Tue, Jun 09, 2009 at 05:48:05AM -0700, Jason Rupert wrote:
> 
> I've got two data.frames and, when certain "keys" match,  I would like to add the column values from one data frame to the other data.frame.
> 
> Below I list the two data.frames, i.e. neighborhoodInfo_df, and schoolZone_df.  Based on the "address" key I would like to add the "schoolZone" key to the neighborhoodInfo_df data.frame.  
> 
> By any chance is there an R command to accomplish this in one or two steps.  I think I could do this in a "for" loop or something, but think there is might be another way in R to accomplish it smarter.  
> 
> Thanks for any info.  
> 
> 
> neighborhoodInfo1_df<-data.frame(address<-c(101),squareFootage<-c(2000),lotsize<-c(0.75))
> 
> neighborhoodInfo2_df<-data.frame(address<-c(108),squareFootage<-c(3000), lotsize<-c(1.25))
> 
> neighborhoodInfo_df<-rbind(neighborhoodInfo1_df, neighborhoodInfo2_df)
> 							    
> 							    
> schoolZone1_df<-data.frame(address<-c(101), schoolZone<-c("Sherman"))
> 						  
> schoolZone2_df<-data.frame(address<-c(108), schoolZone<-c("Baker"))					
> 	  
> schoolZone_df<-rbind(schoolZone1_df, schoolZone2_df)
> 
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