Dear all, I have a time series, which comprises 31 observations per year (actually the observations for March, set in a time series with periodicity 31). My wish is to compact it to the daily average, i.e. end up with 31 observations, each of which represents the average value of that date throughout the available years. I therefore sought to compact it with "dataset compact 31", to which I was told "This conversion is not supported". I then tried other conversions, but it appears no expansion or compaction is accepted at all. I assume this is due to the unorthodox periodicity, but my question is then: how can I successfully compact my data into 31 average values ?

Am 27.02.2016 um 20:09 schrieb Riccardo (Jack) Lucchetti: > On Sat, 27 Feb 2016, Marc O'Callaghan wrote: > >> value of that date throughout the available years. I therefore sought >> to compact it with "dataset compact 31", to which I was told "This >> conversion is not supported". According to the "dataset compact" documentation you would have to give the new frequency, so "dataset compact 1" instead of 31, but you are right that this isn't working, either. I guess it is only implemented for the standard periodicities, although I don't see why it shouldn't be allowed for non-standard cases, too. > Or otherwise, you could use the aggregate() function to create a matrix > that you re-use as the starting point of your new dataset. > To be more concrete, here's an example: <hansl> nulldata 320 setobs 31 1900:1 --time-series matrix m = aggregate(index, $obsminor, mean) print m </hansl> You have to replace "index" with your variable of interest. The builtin series '$obsminor' holds the day-of-the-month number 1 to 31 in this case. You can also do something like: <hansl> nulldata 31 --preserve series mymeans = m[,3] </hansl> at the end to get your results in a series format in a new workfile. (The 3rd column of the 'aggregate' output is what you want, hence m[,3].) good luck, sven _______________________________________________ Gretl-users mailing list Gretl-users(a)lists.wfu.edu http://lists.wfu.edu/mailman/listinfo/gretl-users