Michel,
Would it be advisable - realistic to convert once and for all the old Lytle data from the mono step scale to the energy scale? (I mean, by wirtue of a well-hacked perl macro). Is there any scientific reason why the old mono step scale should be kept?
Possibly. Some of the data is good and useful. The hard part isn't so much the conversion. There are a couple different formats of the Lytle data, but most of the conversion is easy (an ifeffit macro will usually do -- one is given in a FAQ). The hard part is deciding what the good data actually is. That part would require human intervention and better notes about what the data is. It might be doing, but would take some effort.
As such, spec files with all scans cannot be read by Athena, but you can copy out individual "scans" in separate files, for which comment lines all start with "#", the last line given the name of the motors and detectors ("energy", "IO"...) and the data is then ordered as an array. The promblems are (1) usually all scans (table, slits...) are collected in one file, and (2) the column ordering varies from file to file (a problem which is already wonderfully addressed by Athena, though).
So maybe a separate splitting macro to take out the do the job would be more convenient than asking athena to do all theis work. Granted it's tedious, but compared to the time needed to correctly extract, interpret & fit the data...
I have at least two programs to split spec files into individual scans. That part is pretty easy. It's still sometimes a challenge to tell (at least in an automated way) what the columns are. In principle, this information is in the header of the spec file and could be auto-determined, which could probably mean you could automatically separate the energy scans from the slit scans. My simple scripts don't do that. I would imagine that someone at ESRF has dealt with this more completely, but I could find and most my scripts if there's an interest in them. --Matt