R help - Jun 2009 - R command to join data.frames rows with identical keys?

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)

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)
> 
> ______________________________________________
> R-help at 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.

An example:
> schoolZone1_df <- data.frame(address=101,
schoolZone="Sherman")
> schoolZone2_df <- data.frame(address=108, schoolZone="Baker")
> schoolZone_df <- rbind(schoolZone1_df, schoolZone2_df)
> schoolZone_df
  address schoolZone
1     101    Sherman
2     108      Baker
> neighborhoodInfo1_df <- data.frame(address=101, squareFootage=2000,
lotsize=0.75)
> neighborhoodInfo2_df <- data.frame(address=108, squareFootage=3000,
lotsize=1.25)
> neighborhoodInfo_df <- rbind(neighborhoodInfo1_df, neighborhoodInfo2_df)
> neighborhoodInfo_df
  address squareFootage lotsize
1     101          2000    0.75
2     108          3000    1.25
> merge(schoolZone_df, neighborhoodInfo_df, by="address")
  address schoolZone squareFootage lotsize
1     101    Sherman          2000    0.75
2     108      Baker          3000    1.25


  Titus