On Aug 19, 2010, at 4:45 PM, Hall, Ken (CDC/OSELS/NCPHI) wrote:
Please let me know if this is or is not the right place to ask these types of questions. Warning: I am new to R by two days. I have a simple dataset. I have loaded the dataset successfully using the following code: Filepath=(C:\temp\\pilot\dataset1.txt") Pilot=read.table(filepath, header=TRUE) Dataset1.txt is delimited and looks like this: Date illness count 2006/01/01 derm 17 2006/01/01 derm 35 2006/01/02 derm 24 2006/01/02 derm 80 . . . Total records like this approximately 18,000 I would like to use the aggregate function to sum the count by similar date and illness, so it should look like this after the aggregate
Perhaps: with( Pilot, tapply(count, list(Date, illness), sum, na.rm=TRUE) If you need it as a dataframe, then pass the result to: ?as.data.frame.table
2006/01/01 derm 52 2006/01/02 derm 104 . . . And, the illness changes to fever with the same pattern.
Don't understand what that means.
I would like to aggregate the same illnesses by date in the same fashion.
I thought that was what you asked for above.
A nudge in the right direction would be appreciated. Thanks. Ken Hall Computer Scientist Division of Healthcare Information (DHI) (proposed) Public Health Surveillance Program Office (proposed) Office of Surveillance, Epidemiology, & Laboratory Services (OSELS)
Always interested in helping the CDC but I think you may need to be more expansive in your problem descriptions.
David Winsemius, MD West Hartford, CT ______________________________________________ R-help@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.
