About Rational Number (PEP 239/PEP 240)

[Terry Reedy]

|> Since the US, at least, uses
whole/half/quarter/eighth/sixteenth...
| > notes, three-quarter and six-eight time falls out...
|
| I don't think this is technically true, but I've never been able to
| tell the difference.

I learned three-four, four-four, six-eight, etc. as time sigs. Not a
fraction.

 

[Neil Cerutti]

[btw, off topic, in music, isn't 1/4 and 2/8 different? I'm not very
keen of music though, so correct me if I'm wrong.]

As a time signature 1/4 has no sense, but 3/4 and 6/8 are
different things. In the standard musical notation both numbers
are written one above the other, and no "division" line is
used. Note that they just *look* like a fraction when written
in text form, like here, because it's not easy to write one
above the other. 3/4 is read as "three by four", not "three
quarters" -at least in my country- so there is even less
confussion.

Time signatures are crap. They should have switched to a number
over a note value a long time ago; we could have easily avoided
abominable travesties like the time signature on the 2nd
movement of Beethoven's 9th (B needed four over dotted quarter). If
music notation had been invented by a computer scientist we
wouldn't be stuck in the current mess in which 6/8 means two
completely different meters (3 over quarter, or 2 over dotted
quarter).

And... er... Python doesn't need a time signature data type. But
rationals would be quite nifty. ;-)

 

[Dan Upton]

|> Since the US, at least, uses
whole/half/quarter/eighth/sixteenth...
| > notes, three-quarter and six-eight time falls out...
|
| I don't think this is technically true, but I've never been able to
| tell the difference.

I learned three-four, four-four, six-eight, etc. as time sigs. Not a
fraction.

I can't tell whether you're agreeing with me or not...

At any rate though, if time signatures really fell out as reducible
fractions, then why don't we just reduce 4/4 to 1 and call the whole
thing off?

 

[Terry Reedy]

| > | > notes, three-quarter and six-eight time falls out...
| > |
| > | I don't think this is technically true, but I've never been able to
| > | tell the difference.
| >
| > I learned three-four, four-four, six-eight, etc. as time sigs. Not a
| > fraction.
| >
|
| I can't tell whether you're agreeing with me or not...

I disagreed with three-quarter rather than three-four and agreed with
six-eight.

 

[Gabriel Genellina]

[btw, off topic, in music, isn't 1/4 and 2/8 different? I'm not very
keen of music though, so correct me if I'm wrong.]

As a time signature 1/4 has no sense, but 3/4 and 6/8 are
different things. In the standard musical notation both numbers
are written one above the other, and no "division" line is
used. Note that they just *look* like a fraction when written
in text form, like here, because it's not easy to write one
above the other. 3/4 is read as "three by four", not "three
quarters" -at least in my country- so there is even less
confussion.

Time signatures are crap. They should have switched to a number
over a note value a long time ago; we could have easily avoided
abominable travesties like the time signature on the 2nd
movement of Beethoven's 9th (B needed four over dotted quarter). If
music notation had been invented by a computer scientist we
wouldn't be stuck in the current mess in which 6/8 means two
completely different meters (3 over quarter, or 2 over dotted
quarter).

That was proposed by (some great musician from XIX century that I can't
remember) but it's hard to change habits.
The idea was to use: above, number of beats, and below, the note lasting
one beat, *always*. So conventional 6/8 would be 2/"dotted quarter" with a
dotted quarted drawn as itself, not implied by a number. This allows for
more meaningful signatures, like 3+3+2/"eight note" for some Piazzolla
tangos that are now written as 4/4 (but don't have the stress pattern for
4/4 at all).

And... er... Python doesn't need a time signature data type. But
rationals would be quite nifty. ;-)

I'm happy enough with rationals as 3rd party library (like gmpy)

 

[Dafydd Hughes]

Time signatures are crap. They should have switched to a number

That was proposed by (some great musician from XIX century that I can't
remember) but it's hard to change habits.
The idea was to use: above, number of beats, and below, the note lasting
one beat, *always*. So conventional 6/8 would be 2/"dotted quarter" with a
dotted quarted drawn as itself, not implied by a number. This allows for
more meaningful signatures, like 3+3+2/"eight note" for some Piazzolla
tangos that are now written as 4/4 (but don't have the stress pattern for
4/4 at all).

Hi! While I wouldn't agree without reservation that time sigs are crap
(more like they're making the best of a bad situation) I do agree that
number over note value is way better. In fact, the college I teach at
starts with time signatures that way (based on Kodaly): 2 over quarter
note, 2 over dotted quarter etc. It's amazing how well everybody
understands until we switch to 6/8. Then everything falls apart,
because it's no longer intuitive.

cheers
dafydd