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## Re: Compound time signature style

 From: Hans Aberg Subject: Re: Compound time signature style Date: Thu, 6 Nov 2014 18:48:15 +0100

```> On 6 Nov 2014, at 14:46, David Kastrup <address@hidden> wrote:
>
>
>>> Am 04.11.2014 um 07:48 schrieb David Kastrup:
>>>>
>>>>> If the simple-fraction components of a compound time signature respected
>>>>> the time signature style, would that qualify as useful or as undesirable?
>>>>>  For example,
>>>>>
>>>>>  2 + 3                2 + 3   4
>>>>>  ----- + C     vs.    ----- + -
>>>>>    4                    4     4
>>>>
>>>> Undesirable in my book.
>>
>> It seems everyone agrees for once. :)
>>
>> One more case: \compoundMeter #’(n d).  The current implementation
>> prints this as a fraction (n/d), but I plan to change it to honor the
>> style unless somebody objects.
>
> I lean towards not consulting the style here.  \compoundMeter to me
> feels like it should just be numeric.

A compound meter can have the same iterated subaccent structure as otherwise
indicated in the staff by beaming, only that it occurs metrically. In practise,
though, one prefers exceptions. So one idea to implement it would be to have a
sequence of patterns recognizing metric rhythms, each assigning a formal
compound metric structures, the latter is what is used to typeset the beaming
structure.

A brief description of this compound metric structure:

The smallest structure is "in one”: only an accent at the beginning. Write that
as I2, I3, I4, ... (For example, Beethoven’s 5th symphony is normally played
"in one", though written in 2.)

Then one can combine these using "+" and “(...)": a_1 + a_2 + … + a_k means
that there is a stronger accent in the beginning of a_1 than on the other a_i,
but otherwise, the relative strength of the accents beginning the other a_i is
unspecified.

And a_1 + ... + (b_1 + ... + b_l) + ... + a_k (b’s in i-th position) means that
b_1 + ... + b_l starts with an accent as in b_1 = a_i above, and the other
accents b_j, j > 1, are subordinate to that, as above.

When one writes 3, that is ambiguous: at lower speeds, it would be 1+1+1, and
at higher speeds I3. 4 can be 1+1+1+1 or (1+1)+(1+1).

Tuplets p:q start a new “(...)” structure.

```