[Gretl-users] Help regarding time series

Greetings to all, Being a very inexperienced Gretl user, I ran into an issue which must have a simple solution, however I could find it nowhere. My question is the following : In a time series which comprises daily entries over 10 years, how may I select a certain period of each year, i.e. only March-April for instance ? Up to now I have had to resort to a most inefficient solution, although it seems to work, whereby a given variable time (containing only the dates of the entries under a format 20040101, which Gretl doesn't recognise as a date) was used to open a new variable month=int((time-10000*int(time/10000))/100) This works, in that I now have a variable returning the number of each month. I then proceeded to restrict based on the criterion month >= 2 && month <= 4 However the result of this is that I have a series which is not chronological any more. If I convert it back to a time series, it logically gives me a roughly two-year-long period with daily entries. Which means I should proceed to isolate the trimester of each year manually. This is very inefficient and time-consuming. As this is surely not an over-the-top functionality, I assume there must be a simpler and more efficient way of selecting a given period within each year, repetitively over several years. Can someone kindly help me out ? Hoping my explanations were clear, and thanking all in advance, Best, Marc O'Callaghan