[R] dataframe selection using a multi-value key

[jim holtman]

try this:

> merged_data = merge(incidents, responses, by=c("INC_NO", "INC_YEAR"), all=TRUE)
> # responses that don't match
> subset(merged_data, is.na(INC_TYPE), select=c(INC_NO, INC_YEAR, UNIT_TYPE))
   INC_NO INC_YEAR UNIT_TYPE
11      8     2018        E3
12      8     2018        E7
13      8     2018        T1
> # incidents that don't match
> subset(merged_data, is.na(UNIT_TYPE), select=c(INC_NO, INC_YEAR, INC_TYPE))
   INC_NO INC_YEAR INC_TYPE
10      8     2008     FIRE
>


On Tue, Sep 7, 2010 at 8:25 PM, Markus Weisner <maw4b at me.com> wrote:
> I am merging two dataframes using a relational key (incident number and
> incident year), but not all the records match up.  I want to be able to
> review only the records that cannot be merged for each individual dataframe
> (essentially trying to select records from one dataframe using a multi-value
> relational key from the other dataframe).  The following code shows what I
> am trying to do.  The final two lines of code do not work, but if somebody
> could figure out a workable solution, that would be great.  Thanks.
> --Markus
>
> incidents = data.frame(
>        INC_NO = c(1,2,3,4,5,6,7,8,9,10),
>        INC_YEAR = c(2006, 2006, 2006, 2007, 2008, 2008, 2008, 2008, 2009,
> 2010),
>        INC_TYPE = c("EMS", "FIRE", "GAS", "MVA", "EMS", "EMS", "EMS",
> "FIRE", "EMS", "EMS"))
>
> responses = data.frame(
>        INC_NO = c(1,2,2,2,3,4,5,6,7,8,8,8,9,10),
>        INC_YEAR = c(2006, 2006, 2006, 2006, 2006, 2007, 2008, 2008, 2008,
> 2018, 2018, 2018, 2009, 2010),
>        UNIT_TYPE = c("E2", "E2", "E5", "T1", "E7", "E6", "E2", "E2", "E1",
> "E3", "E7", "T1", "E7", "E5"))
>
> merged_data = merge(incidents, responses, by=c("INC_NO", "INC_YEAR"))
>
> relational_key = c("INC_NO", "INC_YEAR")
>
> ## following does not work, but I want DF of incidents that did not merge up
> with responses
> incidents[incidents[,relational_key] %in% responses[,relational_key],]
>
> ## following does not work, but I want DF of responses that did not merge up
> with incidents
> responses[responses[,relational_key] %in% incidents[,relational_key],]
>
>        [[alternative HTML version deleted]]
>
> ______________________________________________
> 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.
>



-- 
Jim Holtman
Cincinnati, OH
+1 513 646 9390

What is the problem that you are trying to solve?