Re: [Gretl-devel] join filter and >=

On Mon, 9 Sep 2013, Sven Schreiber wrote: > At the end of the message I have a real-world data excerpt with all the > realtime data for two periods, namely 2001m10 (aka 2001-10-01) and > 2001m11 (aka 2001-11-01). For certain reasons I'm interested in the > vintage of 2010-06-24, which means the following lines in this example > (with realtime_start_date in the 3rd and realtime_end_date in the 4th > col, see below): > > 2001-10-01 98.4253 20090327 20100624 > 2001-11-01 97.9427 20090327 20100624 > > Inside my functions, I'm using the following join command (where > strvin="2010-06-24": > <hansl> > # and also get the corresponding start dates to verify > join @fpath startdates --tkey=observation_date --time="%Y-%m-%d" \ > --data=realtime_start_date --filter="realtime_end_date >= @strvin" \ > --aggr="seq:1" > </hansl> > > Verbally, this should look for the vintage of 2010-06-24 (with a > workaround: vintages whose validity did not end before the date > 2010-06-24, and take the first of these), and then give me _not_ the > value of the variable, but the date when this vintage was published. > > Now, gretl gives me the following output in the 'startdates' series: > 2001:10 20090327 > 2001:11 20100625 > > Notice that the first value gets the correct publication date (see > above), but the second value is wrong; it is the publication date of the > _following_ vintage, which after applying the filter in join should be > the 2nd matching line, not the 1st one as requested per "seq:1". Or like > I said before, it is as if gretl is partially filtering by ">" instead > of ">=" suddenly. > > Or am I missing a bug in my own commands here? Well, as stated above the "join" command doesn't work with the data given below. Your filter --filter="realtime_end_date >= 2010-06-04" fails since the realtime_* columns are in numerical form, not YYYY-MM-DD.

If I correct the filter to --filter="realtime_end_date>=20100624" I get the results you were expecting. Call your data rtdata.txt. Then the following works OK: