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## Re: Changing autobeaming for 4/4 time

 From: Trevor Daniels Subject: Re: Changing autobeaming for 4/4 time Date: Mon, 10 Aug 2009 23:23:55 +0100

```
Carl, you wrote Monday, August 10, 2009 10:58 PM
```
```
```
On 8/10/09 9:14 AM, "Trevor Daniels" <address@hidden> wrote:
```
```
With all Carl's mods applied just the expected two inconsistencies
```remain:

\relative c'' {
a8 a a16 a a8 a a a a16 a | % wrong, should be ...
a8 a a16[ a a8] a a a[ a16 a] |

```
a32 a a16 a a a a32 a a16 a a a a32 a a16 a a a a32 a | % wrong,
```should be ...
a32[ a a16 a a] a[ a32 a a16 a] a[ a a32 a a16] a a a a32 a
}

The second of these can be fixed (bypassed really) with

```
\overrideBeamSettings #'Score #'(4 . 4) #'end #'(((1 . 32) . (8 8 8
```8)))

which I think is a more acceptable beaming anyway,
but the first is a more fundamental problem which cannot be
fixed by any override which preserves beam breaks at
1/4, 1/2 and 3/4 AFAICS.
```
```
OK, so now I can see the differences.  Thanks, Trevor.

Can you express in words a rule that describes why

a8 a a16[ a a8] a a a[ a16 a16]

is better than

a8[ a a16 a a8] a8[ a a a16 a]

```
? It seems to me that something has triggered a desire to break the beam on
```the beats, when

a8[ a a a] a[ a a a]

is desired to break at 1/2.

```
Perhaps if you can explain this, I can figure out what is missing in the
```autobeaming algorithms.
```
```
I can do no better than quote Ross:

1. [in 4/4 time] "A beam can never be used
to combine notes of the second and third
beats into a unit."

2. "In simple time any beat divided into
more than two parts cannot be connected
to another beat to form a unit."

Apart from these there are no firm rules,
but these explain my beaming.  Rule 1 permits
beaming 4 quavers (sorry, 8th notes) together
(and this seems the common practice), as
quavers have only two parts to a beat, but as
soon as two 16th notes are introduced we have
(at least) three parts to a beat, and rule 2
kicks in, forcing beams to be limited to
single beats.

HTH

Trevor

```