search for: nodup

Sample Data.Frame format Name is Returns.nodup X id ticker date_ adjClose totret RankStk 427225 427225 00174410 AHS 2001-11-13 21.66 100 1235 "id" uniquely defines a row What I am trying to do is filter out id's that have less than 1500 data points (by date) First, I used total<-by(Retu...

hey guys, I am working on a function to make a duplicated value unique. For example, the original vector would be like : a = c(2,1,1,3,3,3,4) I'll like to transform it into: a.nodup = 2, 1.01, 1.02, 3.01, 3.02, 3.03, 4 basically, find the duplicates and assign a unique value by adding a small amount and keep it in order. I come up with the following codes, but it runs slow if t is large. Is there a better way to do it? nodup = function(t) { t.index=0 t.dup=duplicated(t)...

Folks, I'm checking the structure of a dataframe for duplicate parameters at a site station (i.e depth should be measured once, not twice), using aggregate to count each parameter within a site station. The fake data below has only 26000 rows, and takes roughly 14 seconds. My real data has 750000 rows and I had to stop execution after about an hour. The by() function is faster, but I