[R] by-group processing

David Huffer David.Huffer at csosa.gov
Fri May 8 16:57:15 CEST 2009

On Thursday, May 07, 2009 7:45 PM, David Freedman wrote:

 > ...how about:
 >   d=data[order(data$ID,-data$Type),]
 >   d[!duplicated(d$ID),]

Does the "-data$Type" argument to the order function work?

 David Huffer, Ph.D.               Senior Statistician
 CSOSA/Washington, DC           david.huffer at csosa.gov

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