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Documentation get-cs

Hi all,

perhaps I’m looking in the wrong places - is there any documentation for the get-cs function?
I guess it is about getting the coefficient of stability of a vps.
According to this paper http://articles.ircam.fr/textes/Stroppa88a/index.pdf there should exist an s-space that get-cs is referring to. Is it documented somewhere or do I have to dive into the source code?


Just to complete this, in case someone else stumbles upon this: the definition of the s-space can be found in the file globals-vps.lisp in the chroma sources.
One interesting thing: in the paper mentioned above, CS is calculated using GILS whereas the file utils-vps.lisp in the chroma sources seems to use CILS. Can anyone elaborate on this?


Dear pfchph, Thank you for your thorough investigation of the VPS code I wrote almost a quarter of a century ago! The file you looked at, is a sort of “wrap-up” written when Chroma (the lisp-based version) was integrated into OM to become OMChroma. You are right that the name of the intervallic argument to “get-cs” is “cil”, which may be misleading, but this is just a name and it could have been anything. Indeed, as you pointed out, the CS is calculated using a GIL, so a GIL should be passed as an argument (to CIL…). You can see this clearly, for instance, in the method “get-cs” in the file “chord.lisp”.
I hope this reply clears your issue.
Good work!

Dear Marco, thank you very much for your explanation! I’m just starting to get to know Chroma and its conceptual framework. Impressive tools!

Thank you for your nice words. Please, feel free to send more requests or signal possible bugs. I’m still working with and using all this software. If I can help, I’ll do it.

Thank you very much. Perhaps there will be a question concerning the ELET system francescovitale pointed me to in the other thread. But first I have to study the code more deeply.