R repeat function until condition met

Question

I am trying to generate a random sample that excludes certain \"bad data.\" I do not know whether the data is \"bad\" until after I sample it. Thus, I need to make a rando

Answer 1

You can just select the rows to sample directly like so (just 5):

> df <- data.frame(NAME=c(rep('Frank',10),rep('Mary',10)), SCORE=rnorm(20))
> df[sample(which(df$SCORE>0), 5),]


 NAME     SCORE
14  Mary 1.0858854
10 Frank 0.7037989
16  Mary 0.7688913
5  Frank 0.2067499
17  Mary 0.4391216

this is without replacement, for bootstrap put in replace=T.