Tuning-Math Digests messages 6228 - 6252

This is an Opt In Archive . We would like to hear from you if you want your posts included. For the contact address see About this archive. All posts are copyright (c).

Contents Hide Contents S 7

Previous Next

6000 6050 6100 6150 6200 6250 6300 6350 6400 6450 6500 6550 6600 6650 6700 6750 6800 6850 6900 6950

6200 - 6225 -



top of page bottom of page down


Message: 6228

Date: Mon, 27 Jan 2003 06:01:52

Subject: Re: Graham's top 20, with standard vals

From: Carl Lumma

>the 5-limit standard val for 12 is [12, 19, 28] since that's how
>many semitones are in a 2:1, a 3:1, and a 5:1.

Ah, ok.  THANKS PAUL.

>a non-standard val for 12 would be [12, 19, 27] since you'd be
>using 27 semitones, instead of 28 semitones, to approximate 5:1.

What's a non-standard val?  Why?

-Carl


top of page bottom of page up down


Message: 6233

Date: Mon, 27 Jan 2003 07:20:03

Subject: Re: Graham's top 20, with standard vals

From: Carl Lumma

> gene defined "standard val" (not something i'd be particularly 
> interested in) as where each prime is mapped to its best 
> approximation in N-equal -- in this case, 12-equal.

???  Could you explain your reasoning here?

-C.


top of page bottom of page up down


Message: 6235

Date: Mon, 27 Jan 2003 07:26:24

Subject: Re: New file uploaded to tuning-math

From: Carl Lumma

> Yahoo groups: /tuning-math/files/Paul/zooms.gif * 

Awesome.  -C.


top of page bottom of page up down


Message: 6236

Date: Mon, 27 Jan 2003 07:28:46

Subject: Re: Graham's Top 20 13-limit temperaments

From: Carl Lumma

> try now:
> 
> Yahoo groups: /tuning/database? *
> method=reportRows&tbl=10&sortBy=4

Sign In - *

**Now we're talking**.  Sorting by the denominator
of the comma really works better than anything I
tried on Dave's spreadsheet.

Aside from the order, what bounds were used to
select temperaments for this list?

-Carl


top of page bottom of page up down


Message: 6237

Date: Mon, 27 Jan 2003 07:30:08

Subject: Re: Graham's top 20, with standard vals

From: Carl Lumma

>my reasoning in not being particularly interested in this?
>it's that, like graham, i don't think the standard val is
>necessarily the best val for any ET. try 64-equal in the
>5-limit.

This wouldn't happen in a linear temperament, though, right?


top of page bottom of page up down


Message: 6242

Date: Tue, 28 Jan 2003 12:04:50

Subject: Re: Calculating geometric complexity II

From: Graham Breed

Gene Ward Smith  wrote:

>>Oh, that's good.  It should be the same as my invariant.  But are 
>>7-limit wedge products taken from vectors or vals?
> 
> Either, but I follow the val ordering.

Okay, so that's the one that give the mapping correctly

>>I get 7-limit meantone as 21.97, 11-limit meantone as 31.72 and 
>>h12^h19^h22 in the 11-limit as 29.52.  The planar temperament with 
>>441:440 and 225:224 is 34.44.
> 
> I'm afraid I don't know what these numbers mean. I have

They're geometric complexity, calculated from your algorithm!  Look at 
the subject line!!!!

Why are you using natural logarithms in the definition?  I have my 
standard arrays as logarithms to base 2, and that's the metric that 
gives interval sizes in octaves.  It'd be much easier if geometric 
complexity stayed in base 2.

> 7-limit meantone: h50^h31 = 126/125^81/80 = [1, 4, 10, 12, -13, 4]

Okay, we're already in trouble.  I make this val

(0, 1): 1
(0, 2): 4
(0, 3): 10
(1, 2): 4
(1, 3): 13
(2, 3): 12

That'd be an invariant of

[1, 4, 10, 4, 13, 12]

Which isn't what you give!  You must be using (3,1) instead of (1,3) for 
the sign to match.  And the ordering isn't the same, and I don't see how 
that can be numerical order of the bases, whatever the bases are.  So 
what other surprises do you have up your sleeve?

I'm fully in agreement with the calculations for wedge product and 
complement given in

Grassmann Algebra Book *

where my bases are the coefficients of his e's (except that I start with 
0 instead of 1).  So can you please state your algorithms in terms of these?

> h12^h19^h22 = 100/99^225/224 = [-1,2,-2,2,2,-8,-5,-2,14,-6]

(0, 1, 2): 1 *
(0, 1, 3): 2
(0, 1, 4): 2 *
(0, 2, 3): -2 *
(0, 2, 4): 2
(0, 3, 4): 8 *
(1, 2, 3): -5
(1, 2, 4): 2 *
(1, 3, 4): 14
(2, 3, 4): 6 *

Here, it's the right order but the signs are wrong.  It's also different 
to the invariant I defined, which always converts to the smaller bases. 
  I can change that to always have the dual flag set and I don't think 
there'll be any repercussions.  And the signs don't matter for the 
complexity calculation, so this one's okay.

> 225/224^441/440 = h41^h31^h12 = [1,-2,3,-2,6,-6,5,-13,11,-4]

> I
said I was using duality to identify compliments. I started out trying
to do things the right way, as you seem to be doing, but it gave me
trouble, so I settled for a fast, simple-minded approach, which means
I have a separate program for each kind of wedge product I want to
take. 

No, you've repeatedly said things like the the wedge product of 2 vals

is the same as that of n-1 commas, which only works if you use
duality. 
  I'd rather keep the complements in there, explicit is better than 
implicit and all that.  But now I've implemented duality to fit in
with 
you, you say you've been taking complements all the time!

Oh, and "compliment" and "complement" are different words.

>>reversing the list will do the trick?  Some of the coefficients
should 
>>be negated if you aren't using a special ordering.
> 
> Sometimes I do. I simply make the wedge product of "vectors", or
what I would call intervals, correspond to the wedge product for vals,
which I take as the basis.

So can you give the general algorithm for geometric complexity?  I
think 
I've got an interior product worked out, but (as with the complement) 
only for the Euclidian metric.  Which Browne says is the identity 
matrix, although you have some other metric that you also say is
Euclidian.


                         Graham


top of page bottom of page up down


Message: 6244

Date: Tue, 28 Jan 2003 14:35:19

Subject: Re: Calculating geometric complexity II

From: Graham Breed

Gene Ward Smith  wrote:

> People define things in different ways;
you could introduce interior products, for instance. The way Browne
does things is a little unusual and I haven't been trying to follow
him. For our musical purposes, as far as I can see we only need to
multiply by either vals or intervals, and we can, if we like, consider
that the kind of product is determined by whether we are taking it
with a val or an interval.

So far, all we need are wedge products and complements.  But you only 
defined wedge products -- I had to work out the complement for myself.

If the wedge product works on general multivectors, there's no need to

distinguish vals from intervals.  Even if the distinction is
preserved, 
you need to do complements, they're just hidden away.

The only text I have is Browne's, so if you're using different 
definitions, how are any of us supposed to know what you mean?

>>So can you give the general algorithm for geometric complexity?  I
think 
>>I've got an interior product worked out, but (as with the
complement) 
>>only for the Euclidian metric.  Which Browne says is the identity 
>>matrix, although you have some other metric that you also say is
Euclidian.
> 
> 
> If you consider both vals and intervals to be 1-vectors, then the
mapping of an interval by the val is an inner product. Mostly,
mathematicians would simply leave the vals and intervals to be dual
spaces, and identify the double dual with the original space. That's
one possible kind of metric, but we don't actually need to make it a
metric if we don't do things in Browne's way but in a more usual way.

The inner product can be calculated from wedge products and
complements. 
  There's no need to bring dual spaces into it.  It's the only way I 
know to get the size of a wedgie, and for it to work as a complexity 
measure a metric needs to be applied to the complement operation.  It 
does need to work beyond 1-vectors because we need to get the
complexity 
of other wedgies.

> The metric I am using for geometric complexity is a metric not on
intervals, but on octave classes.

What's an octave class?

> The classes are 1-vectors in a space of one less dimension, and the
wedge products are being taken in this different space.

You mean it's octave-equivalent space?  Well, we've always been able
to 
rate the complexity of the mapping.  We need to get the complexity of 
intermediate wedgies, like spatial temperaments in 13-equal.

 > This now is the situation as Browne envisions it, except that we
are 
not using an orthonormal basis.

We aren't?

> However, a coordinate transformation will take us to such a basis,
which means that elements of any grade can be measured--we are in a
Euclidean setting, which from my point of view we are *not* in when we
start with vals and intervals, where we are in a vector space V and
its dual space V^* setting.

So what's the transformation?  And how do you transform coordinates of

wedgies anyway?


                           Graham


top of page bottom of page up down


Message: 6248

Date: Tue, 28 Jan 2003 12:10:58

Subject: Re: A common notation for JI and ETs

From: David C Keenan

--- In tuning-math@xxxxxxxxxxx.xxxx "gdsecor <gdsecor@y...>" <gdsecor@y...> 
wrote:
 > There may or may not be trouble in keeping a clear distinction
 > between ` and ' and between . and , -- but we're scraping the bottom
 > of the barrel looking for characters.

There would be trouble. We can either use obviously different characters as 
you've suggested, or we could attempt to outlaw the use of the 5'-comma 
symbols in the shorthand. But I don't think the latter will work. It's too 
obvious a thing to want to do.

Incidentally, I think we should point out that the 5'-comma symbol should 
stay to the left of any arrow symbol, even in text, so they're always 
treated as a single compound symbol. e.g.
Score:  ./| # C-notehead
Text:   C#./

This will also reduce the problem of . being taken as punctuation.

 >  I think that " for up and ;
 > for down might be somewhat better (and certainly no worse than ' and
 > `) for the 5:7 comma.

I don't know where you got ' and `) from. Typos?
Oh. Now I see that ) was a closing parenthesis, another good reason not to 
use ( or ) in the shorthand.

Similarly, we shouldn't use a comma , for anything since it would make 
punctuating sentences rather fraught. But why " and ;? Why not " and :? I 
suppose one reason is that we sometimes want to write C:G just as we write 2:3.

Semicolon is rarely used for punctuation or anything else. Except we do 
have Paul Erlich's usage, which I quite like, which is instead of : in 
commas. For example we write 80;81 to make it clear that we mean the 
interval in some tuning that functions as the syntonic comma but is not 
necessarily 21.5 cents. The semicolon there only appears between numbers, 
not letters, so there's no problem.

Since we need small symbols for the 5:7 comma and I can't think of anything 
better, I reluctantly agree with " and ; although they bear no resemblance 
to the graphicals.

 > If you make y up and h down, then the characters will more closely
 > resemble the symbols, according to which direction the shaft sticks
 > out.  I realize that the y has a lower vertical placement relative to
 > the h, but consider how the actual symbols would be placed relative
 > to one another for a notehead in a given position.  (See also my
 > comments for the 5:11 comma below.)

Agreed.

 > > ~| ~ 17-comma sharp 2176:2187
 > > ~! $ or z 17-comma flat
 >
 > Of course, ~ couldn't be any better. But how would s work as the
 > down symbol? It does combine the best features of both $ and z.

The problems I have with s are
1. It can be confused with plurals, e.g. one C two Cs. Writing one C two 
C's doesn't help either since the apostrophe is the 5'-up symbol.
2. Just as we have d for down, we have s for sharp (the wrong direction). 
And for this reason I must now reject $ which even _looks_ like a kind of 
half-sharp symbol.

"z" doesn't carry any of this baggage and while it doesn't look as much 
like the sagittal I can accept it because we already have some other 
angular characters paired with rounded ones. h and y, w and m.

But if, after considering the above, you still prefer "s", and no-one else 
objects ...

Hello everyone else, you're welcome to give your opinions on these.

... then I'll go with the "s".

 > I would make q the up symbol and d the down character (according to
 > which direction the arrow shaft protrudes).  Then compare the
 > resemblance between the 7:11 and 5:11 comma characters, specifically
 > the part of each character where the convex curve is located:
 >
 > up:    ?   q
 > down:  j   d
 >
 > (It would also help to remember that "d" could stand for "down.")

Agreed.

 > > //|   //      25-diesis sharp  6400:6561
 > > \\!   \\      25-diesis flat
 >
 > This is a combination of two characters, but it's an exception that
 > is easily justified.

Yes. Not to mention that we can't find a single character that looks 
anything like them! "F" looks a bit like //| but can't be used for obvious 
reasons.

 > > (|)   @       11'-diesis sharp 704:729
 > > (!)   U or o  11'-diesis flat
 >
 > @ is very good!  I would use o rather than U, since
 > 1) All of the other down symbols that are letters are lower case; and
 > 2) There is already a lower-case u being used, so 'o' would be less
 > confusing.

Yes. It is good not to use any uppercase. This also allows the sagittals to 
be used for linear temperament notations that might use more that 7 
nominals. Other uppercase letters can then be used for the nominals.

 > Not counting the 5' and apotome pairs, it's actually 13 pairs.  I
 > snuck both the 55 and 7:11 comma symbols in there for 6deg217.  As a
 > consequence, we also have all of the symbols needed for a 15-limit
 > tonality diamond.
 >
 > This then covers all of the ETs in Table 3 and around half of those
 > in Table 4 (in general, the ones that don't use the 19-comma symbol).

Wonderful.

 > > >   (Or are you intending to combine
 > > >those single-character ascii symbols in any way?)
 > >
 > > No.
 >
 > Okay.  That way we keep the shorthand simple.

Of course I intend that # or b (apotome) and ' or . (5'-comma) may be 
combined with any of the others, and // may occur, but any other 
combinations of these shorthand symbols would represent multiple sagittal 
symbols in the obvious way (we may yet find a use for this).

It's unfortunate that we can't allow the traditional use of x instead of ## 
in this shorthand notation without creating ambiguous symbols. Is there any 
chance we could find some other ASCII character for the down x-shaft? How 
about k?

By the way George, I hope you realise I still think there are serious 
problems with the triple shafts and X shafts. It's only the availability of 
the dual-symbol version of the notation that allows me to ignore them.

Here's what we've got now (in order of size relative to strict Pythagorean)

'|    '       5'-comma sharp 32768:32805
.!    .       5'-comma flat
  |(   "       5:7-comma sharp  5103:5120
  !(   ;       5:7-comma flat
~|    ~       17-comma sharp  2176:2187
~!    z or s  17-comma flat
~|(   y       17'-comma sharp  4096:4131
~!(   h       17'-comma flat
/|    /       5-comma sharp 80:81
\!    \       5-comma flat
  |)   f       7-comma sharp 63:64
  !)   t       7-comma flat
  |\   &       55-comma sharp 54:55
  !/   %       55-comma flat
(|    ?       7:11-comma sharp 45056:45927
(!    j       7:11-comma flat
(|(   q       5:11-comma sharp  44:45
(!(   d       5:11-comma flat
//|   //      25-diesis sharp  6400:6561
\\!   \\      25-diesis flat
/|)   n       13-diesis sharp 1024:1053
\!)   u       13-diesis flat
/|\   ^       11-diesis sharp 32:33
\!/   v       11-diesis flat
(|)   @       11'-diesis sharp 704:729
(!)   o       11'-diesis flat
(|\   m       13'-diesis sharp 26:27
(!/   w       13'-diesis flat
/||\  #       apotome sharp 2048:2187
\!!/  b       apotome flat
/X\   ## or x apotome sharp 2048:2187
\x/   bb      apotome flat

George, whatever you decide on for the 17-comma flat and the apotome sharp, 
could you please add these symbols to your quick reference. And when you 
have time, could you add the sequence of these single-character ASCII 
symbols for some of the most common ETs. In particular the ones that have 
come up in linear temperament notation discussions.
-- Dave Keenan
Brisbane, Australia
Dave Keenan's Home Page *


top of page bottom of page up down


Message: 6249

Date: Tue, 28 Jan 2003 12:47:23

Subject: Re: A common notation for JI and ETs

From: David C Keenan

I've added one more pair below. Since, according to Manuel's statistics, 
the ratios it notates (49 with various powers of 2 and 3) are more common 
(1.6%) than many others on this list, and it's a no-brainer to notate. This 
list has 86% of the ratio ocurrences covered.

'|    '       5'-comma sharp 32768:32805
.!    .       5'-comma flat
  |(   "       5:7-comma sharp  5103:5120
  !(   ;       5:7-comma flat
~|    ~       17-comma sharp  2176:2187
~!    z or s  17-comma flat
~|(   y       17'-comma sharp  4096:4131
~!(   h       17'-comma flat
/|    /       5-comma sharp 80:81
\!    \       5-comma flat
  |)   f       7-comma sharp 63:64
  !)   t       7-comma flat
  |\   &       55-comma sharp 54:55
  !/   %       55-comma flat
(|    ?       7:11-comma sharp 45056:45927
(!    j       7:11-comma flat
(|(   q       5:11-comma sharp  44:45
(!(   d       5:11-comma flat
//|   //      25-diesis sharp  6400:6561
\\!   \\      25-diesis flat
/|)   n       13-diesis sharp 1024:1053
\!)   u       13-diesis flat
/|\   ^       11-diesis sharp 32:33
\!/   v       11-diesis flat
|))   ff      49'-diesis sharp 3969:4096   might be (/|
!))   tt      49'-diesis flat              might be (\!
(|)   @       11'-diesis sharp 704:729
(!)   o       11'-diesis flat
(|\   m       13'-diesis sharp 26:27
(!/   w       13'-diesis flat
/||\  #       apotome sharp 2048:2187
\!!/  b       apotome flat
/X\   ## or x apotome sharp 2048:2187
\x/   bb      apotome flat


top of page bottom of page up

Previous Next

6000 6050 6100 6150 6200 6250 6300 6350 6400 6450 6500 6550 6600 6650 6700 6750 6800 6850 6900 6950

6200 - 6225 -

top of page