Normal forms: Difference between revisions

Haidilao (talk | contribs)
Changed a wrong calculation (13 is correct which was written as -13)
m Normal forms for commas: adopt template. Tenney height -> Tenney norm
 
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=== Minimal form ===
=== Minimal form ===
The ''minimal form'', or ''reduced form'' shows the simplest comma list sufficient to define the temperament, where the commas are rated by a complexity measure such as the [[Tenney height]], in which case it is called the ''Tenney-minimal form''. It is obvious why this form is useful, but unfortunately, it is not easy to find since it is equivalent to the ''shortest basis problem'', an NP-hard problem. The [[LLL reduction]] algorithm gives a good approximation. Otherwise, it is typically solved heuristically by hand.  
The ''minimal form'', or ''reduced form'' shows the simplest comma list sufficient to define the temperament, where the commas are rated by a complexity measure such as the [[Tenney norm]], in which case it is called the ''Tenney-minimal form''. It is obvious why this form is useful, but unfortunately, it is not easy to find since it is equivalent to the ''shortest basis problem'', an NP-hard problem. The [[LLL reduction]] algorithm gives a good approximation. Otherwise, it is typically solved heuristically by hand.  


'''Note''': This is the form shown in the "comma lists" of each temperament on this wiki.
{{Note| This is the form shown in the "comma lists" of each temperament on this wiki. }}


=== Antitransposed defactored Hermite form ===
=== Antitransposed defactored Hermite form ===