search for: sd_2

...e the cause for the NA's being returned? Also, should TukeyHSD similarly return a warning about this situation? Thanks again for any insights and feedback. length_1<-1 mean_1<-0.0 sd_1<-0.0 distribution_1<-rnorm(length_1, mean=mean_1, sd=sd_1) length_2<-750 mean_2<-0.5 sd_2<-0.0 distribution_2<-rnorm(length_2, mean=mean_2, sd=sd_2) length_3<-850 mean_3<-0.1 sd_3<-0.65 distribution_3<-rnorm(length_3, mean=mean_3, sd=sd_3) length_4<-850 mean_4<-0.0 sd_4<-0.65 distribution_4<-rnorm(length_4, mean=mean_4, sd=sd_4) columns_A<-data.fram...

I have data that looks like this: > df1 group id 1 red A 2 red B 3 red C 4 blue D 5 blue E 6 blue F I want a list of the groups containing vectors with the ids. I am avoiding subset(), as it is only recommended for interactive use. Here's what I have so far: df1 <- data.frame(group=c("red", "red", "red", "blue",