[Gretl-users] join command - syntiax

Hi all I am sorry tho ask help. Before asking here i studied the newest copy of the Guide, sought in the list whitout result. I am surely making a trivial mistake using "join" command but i am unable to bypass it by myself. I want to join variable CHIUSURA in a2.gdt, with a1.gdt a1.gdt obs ch1 2014-01-02 0,8000 2014-01-03 0,8425 2014-01-06 0,8485 2014-01-07 0,9060 2014-01-08 0,8790 2014-01-09 0,8660 2014-01-10 0,8370 2014-01-13 0,8690 2014-01-14 0,8625 2014-01-15 0,8560 a2.gdt obs CHIUSURA 2014-01-02 19,97 2014-01-03 21,40 2014-01-06 22,08 2014-01-07 21,55 2014-01-08 21,81 2014-01-09 21,49 2014-01-10 20,86 2014-01-13 21,00 2014-01-14 21,10 2014-01-15 21,00 this is the script #open the left hand database open /home/guido/gretl/Star/a1.gdt #join the CHIUSURA var in a2.gdt join /home/guido/gretl/Star/a2.gdt CHIUSURA this is the output log gretl versione 1.9.91 Sessione corrente: 2014-11-27 16:35 #open the left hand database ? open /home/guido/gretl/Star/a1.gdt Lettura del file dati /home/guido/gretl/Star/a1.gdt Periodicità: 5, oss. max.: 10 Intervallo delle osservazioni: 2014-01-02-2014-01-15 2 variabili elencate: 0) const 1) ch1 #join the CHIUSURA var in a2.gdt ? join /home/guido/gretl/Star/a2.gdt CHIUSURA [Sorry, the command is not available for this estimator] Errore nell'esecuzione dello script: abbandono Thx for any suggestion. Guido