I've a datafile in which every row is a observation. Each observation is done on a specific date. So for example on 1 specific date i have 3 observation, and for another observation i have 23 observations. Each date has a different number of observations.
I now want to create a new variable which provides me for each date the number of observations on that date.
Does somebody know how to do that is just a few lines of syntax!? I thought it had something to do with count and loops but i can figure it out!
I need a sort syntax instead of a
Code: Select all
if datum_num =20110222 n_datum = 2.
Please help me!