Thank you very much. I am a newcomer to R and your quick response is very much appreciated. I obviously have more reading to do.
pk HBaize wrote: > > > What I think you are missing is that you didn't change ddd. The ifelse > statement does not assign values to the ddd object. To change ddd it would > read: > > ddd <- ifelse ( ddd>360, ddd-360, ddd ) > > So when you enter "print(ddd)" you get the content of the original object, > which has not changed. > > What is missing from your examples below is the output of the ifelse > statement. When I run your second example (I can't run the first because > you didn't supply the data objects) > I get the following: > >> ddd <- c(461, 213, 238, 249, 251) >> print(class(ddd)) > [1] "numeric" >> >> print(ddd) > [1] 461 213 238 249 251 >> >> ifelse ( ddd>360, ddd-360, ddd ) > [1] 101 213 238 249 251 >> print(ddd) > [1] 461 213 238 249 251 >> > > Which is perfectly reasonable given that the ifelse does not change the > ddd object. > > > > pking wrote: >> >> When I run this code from an R-script: >> ddd = 360 + round ( atan2(-u,-v) / d2r ) >> print(class(ddd)) >> print(ddd) >> ifelse ( ddd>360, ddd-360, ddd ) >> print(ddd) >> >> I get this output: >> [1] "numeric" >> [1] 461 213 238 249 251 >> [1] 461 213 238 249 251 >> >> Why does ifelse not change the 461 to 101? >> >> I recreated the vector ddd and ran the same ifelse >> code and it did work as expected. >> >>> ddd <- c(461, 213, 238, 249, 251) >>> print(class(ddd)) >> [1] "numeric" >> >>> print(ddd) >> [1] 461 213 238 249 251 >> >>> ifelse ( ddd>360, ddd-360, ddd ) >>> print(ddd) >> [1] 101 213 238 249 251 >> >> What am I missing? >> >> Patrick King >> >> >> > > -- View this message in context: http://www.nabble.com/ifelse-tp26041165p26041853.html Sent from the R help mailing list archive at Nabble.com. ______________________________________________ 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.
