On 06/03/2026 06:30, Ramki S wrote:
Hi,
1. Can gretl recognize the ymd hms format dates automatically?
It depends on what you mean by "automatically": gretl has several
functions for manipulating calendar dates. Chapter 19 of the User's
Guide is devoted to this. For example, if you read a csv file that looks
like this:
datestr,x
"2025-04-06 12:00:00",22
"2025-04-06 12:30:00",24
"2025-04-06 13:00:00",45
"2025-04-06 13:30:00",NA
"2025-04-06 14:00:00",16
gretl will read column 1 as a string. You can convert it into the "Unix
seconds" format using the function "strptime", as in
<hansl>
series ut = strptime(datestr, "%Y-%m-%d %H:%M:%S")
</hansl>
2. If the data is 30 min frequency data, how to tell gretl?
If you consider the day as the "larger" time unit, than you have 24
subperiods in a period and all you need to do is
<hansl>
setobs 24 1:1 --special-time-series
</hansl>
You can achieve the same effect via the GUI: go to the "Data" menu and
choose "Dataset structure".
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Riccardo (Jack) Lucchetti
Dipartimento di Scienze Economiche e Sociali (DiSES)
Università Politecnica delle Marche
(formerly known as Università di Ancona)
r.lucchetti(a)univpm.it
http://www2.econ.univpm.it/servizi/hpp/lucchetti
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