Hi all, I'm encountering an error with the recent gretl snapshot (v2025c) related to the gnuplot command. The problem arises when using some options like --dummy and/or --factorized with discrete series. By the way, I realized that the --dummy option is not documented anymore(?) (I am pretty sure it was listed in the past). Probably, this option got superseded by the --factorized option recently (see below). Below is a minimal example illustrating the issue: <hansl> set verbose off open mrw.gdt --quiet # "OECD" is a discrete series (see series attributes) # Note: The following "works" technically, but only 3 data points are shown! # This used to work in the past: gnuplot gdpgrow school OECD --dummy --output=display # This works without error, but again only 3 instead of 121 points are shown gnuplot gdpgrow school OECD --factorized --output=display # This returns an error "Invalid argument": gnuplot gdpgrow school OECD --factorized=OECD --output=display # After executing the above line, the following also fails with "Invalid argument" # even though it worked before: gnuplot gdpgrow school OECD --factorized --output=display </hansl> This may be connected to the recent update in version 2025b according to the changelog: <> 2025-06-05 Version 2025b - "gnuplot" command: generalize the --dummy functionality for factorized plots; update and improve the help text </> I am working under Ubuntu and have gnuplot version 6.0 patchlevel 2 installed Do you guys face the same error? Artur