Re: "smart" transposition of key signatures

[Janek Warchoł]

2013/10/7 David Kastrup <address@hidden>:
> Kieren MacMillan <address@hidden> writes:
>
>> Hello all,
>>
>> I've got a piece in which the key centres move thusly:
>>
>>    E major  -->  F minor  -->  A major  -->  F major  -->  E major
>>
>> I need to transpose it up a few pitches, as it was originally written for 
>> medium voice, but is going to be sung by a high[er] tenor.
>>
>>   \transpose e g ==>    G major  -->  G# minor  (= B major) -->  C major  
>> -->  Ab major  -->  G major
>>
>> would be great… except what's actually happening is
>>
>>   \transpose e g ==>    G major  -->  Ab minor  (= Cb major, with 7 
>> flats!!!) -->  C major  -->  Ab major  -->  G major.
>>
>> Is there any way (like the "naturalizeMusic" function for individual notes) 
>> to ensure that the key signatures in a transposed piece are the "most 
>> logical"?
>
> [...]
>
> Now if we assume that we have not already left the good pitches behind
> and that we won't need more than one corrective rotation around the
> harmonic circle (both are somewhat correlated), we can hook into the
> iterator: at that time, all transposition should be over.
>
> That gives us something like [snippet]

Awesome!
Janek