On Wed, 20 May 2026 10:03:20 +0200, fir wrote:
Lawrence D?Oliveiro pisze:
i dont know in fact but i dont think so - imo 0...1 has more sense
Radians are the most natural unit for most trig calculations.
In radians,
sin x ? x as x ? 0
But only in radians.
On 21/05/2026 03:23, Lawrence D?Oliveiro wrote:
On Wed, 20 May 2026 10:03:20 +0200, fir wrote:
Lawrence D?Oliveiro pisze:
i dont know in fact but i dont think so - imo 0...1 has more sense
Radians are the most natural unit for most trig calculations.
In radians,
ÿÿÿ sin x ? x as x ? 0
But only in radians.
Radians are clearly the most appropriate units of angle from a
mathematical viewpoint.ÿ But in practical use in programming, other
units can often make more sense.ÿ 0..1 floating point is one option, as
are degrees, or scaled integers (0 .. 2 ** n - 1 ranges are common in
motor control systems).ÿ If you are using floating point, then usually
it's a small matter to scale them when you need to - so sticking to
radians makes sense.ÿ And if you are using integers to get maximal efficiency on small systems, then every system will be different
(because of different accuracy / efficiency trade-offs) so there is no reason to pick any one choice.
Lawrence D?Oliveiro pisze:
On Wed, 20 May 2026 10:03:20 +0200, fir wrote:
Lawrence D?Oliveiro pisze:
i dont know in fact but i dont think so - imo 0...1 has more sense
Radians are the most natural unit for most trig calculations.
In radians,
ÿÿÿ sin x ? x as x ? 0
But only in radians.
i dont see any sense in thsi becouse what you sin is not x its angle
(and your x is not x in fact but y..becouse if sin is close to 0
y get close to 0 x gets close to 1)
and who said d(dangle)/d(y)should be 1? no sense to me (im not scholer
in math though)
for practical cpu reasons imo 0..1 seems much better (and radian seem
maybe most stupider)
if you got angle 0.001 you know its a 1/1000 of full circle..whats wrong with that
so why its not implemented on x64 pus?
i asked ai yet
fir again:
im not sure though if i agree in what ai said..im also not quite sure it
it would not help (speedup) classical trygonometry maybe
Summary:
For the whole software ecosystem:
essentially negligible.
For phase-heavy kernels:
potentially very noticeable.
For DSP/audio/simulation:
a genuinely meaningful idea.
Historically:
it could have been quite powerful.
Mathematically:
it is a very elegant concept.
Architecturally:
the problem is too niche for mainstream x64 ISA support.
to pick a best choice has very sense becouse if no it makes "babel
twoer" (if its called in english?)
Lawrence D?Oliveiro pisze:
i dont see any sense in thsi becouse what you sin is not x its angle
In radians,
sin x ? x as x ? 0
But only in radians.
[...]
I have no problem with supporting different angle units. Let the user
input angles in whatever units they want, and get back answers in
whatever units they want. Internally, all angles get converted to
radians, the calculations are done, and the results converted back
again.
What annoys me just a bit is seeing these little functions like
?degrees to radians? and ?radians to degrees? -- so you need two
conversion functions (converting to and from radians) for every angle
unit you want to support.
It?s simpler to just offer a single conversion factor, which can be
used like this:
®angle-in-units-X¯ ? ®conversion-factor-for-units-X¯ ? ®angle-in-radians¯
and going the other way:
®angle-in-radians¯ ö ®conversion-factor-for-units-X¯ ? ®angle-in-units-X¯
So for example if you want angles in degrees, then the conversion
factor is ã/180; if you want to work in units of full circles, then
the conversion factor is 2ã. All nice and simple, and scalable, too.
On Thu, 21 May 2026 21:42:08 +0200, fir wrote:
Lawrence D?Oliveiro pisze:
i dont see any sense in thsi becouse what you sin is not x its angle
In radians,
sin x ? x as x ? 0
But only in radians.
What is an angle? It?s just a ratio of two lengths, the arc
circumference to the arc radius. Distance ö distance = a ratio which
is a pure number, with no units.
Start with the Euler identity:
$$e^{ix} = \cos x + i \sin x$$
and, from the well-known expansion for $e^{x}$, you get
$$\sin x = x - {x^3 \over 3!} + {x^5 \over 5!} - {x^7 \over 7!} ...$$
$$\cos x = 1 - {x^2 \over 2!} + {x^4 \over 4!} - {x^6 \over 6!} ...$$
But again, all this works only in radians.
Lawrence D?Oliveiro pisze:
On Thu, 21 May 2026 21:42:08 +0200, fir wrote:
Lawrence D?Oliveiro pisze:
i dont see any sense in thsi becouse what you sin is not x its angle
In radians,
ÿÿÿÿ sin x ? x as x ? 0
But only in radians.
What is an angle? It?s just a ratio of two lengths, the arc
circumference to the arc radius. Distance ö distance = a ratio which
is a pure number, with no units.
Start with the Euler identity:
ÿÿÿÿ $$e^{ix} = \cos x + i \sin x$$
and, from the well-known expansion for $e^{x}$, you get
ÿÿÿÿ $$\sin x = x - {x^3 \over 3!} + {x^5 \over 5!} - {x^7 \over 7!}
...$$
ÿÿÿÿ $$\cos x = 1 - {x^2 \over 2!} + {x^4 \over 4!} - {x^6 \over 6!}
...$$
But again, all this works only in radians.
ai said that with radians d(sin(x)) / dx =cos(x)
but i dont get it - im not sure it should.. for example in c
programming i used many sin cos but not calculated d sin(x)/ dx
so i dont need it anyway in this 0..1 angle you have d sin(x)/dx = 2*pi*cos(x) so you can multiply and then you need to use this 2*pi much
more rare which seems fortunate
c coding is not exactly midlle school book mathematics
THATS A PROOF - radians suck (and should be thrown out both c and math)
I use radians all the damn time!
On 5/22/2026 4:54 AM, fir wrote:
[...]
THATS A PROOF - radians suck (and should be thrown out both c and math)
Huh? Wow. That's a bold statement. I use radians all the damn time!
How many degrees is pi / 2 ?
Chris M. Thomasson pisze:
On 5/22/2026 4:54 AM, fir wrote:
[...]
THATS A PROOF - radians suck (and should be thrown out both c and math)
Huh? Wow. That's a bold statement. I use radians all the damn time!
How many degrees is pi / 2 ?
degrees are less bad but also bad so dont ask how many degress but maybe
how in this natural measure is what is "pi/2" in radians... its 0.25 as
2*pi ~ 1.0
On 5/23/2026 5:44 AM, fir wrote:
Chris M. Thomasson pisze:
On 5/22/2026 4:54 AM, fir wrote:
[...]
THATS A PROOF - radians suck (and should be thrown out both c and math) >>>Huh? Wow. That's a bold statement. I use radians all the damn time!
How many degrees is pi / 2 ?
degrees are less bad but also bad so dont ask how many degress but maybe
how in this natural measure is what is "pi/2" in radians... its 0.25
as 2*pi ~ 1.0
pi/2? Oh man, you know!
? 2026/5/24 14:42, Chris M. Thomasson ??:
On 5/23/2026 5:44 AM, fir wrote:
Chris M. Thomasson pisze:
On 5/22/2026 4:54 AM, fir wrote:
[...]
THATS A PROOF - radians suck (and should be thrown out both c and
math)
Huh? Wow. That's a bold statement. I use radians all the damn time!
How many degrees is pi / 2 ?
degrees are less bad but also bad so dont ask how many degress but maybe >>> how in this natural measure is what is "pi/2" in radians... its 0.25
as 2*pi ~ 1.0
pi/2? Oh man, you know!
I guess fir has a religious hatred of irrational numbers, so much that
their mind will have to twist reality when these are really needed.
By a similar logic, we should also nuke sqrt(3), exp(3) and log(3) from
C and math, because these generate a shit ton of irrational numbers.
Even Roman mathematicians from around 2,000 years ago will treat me as
a fool when I suggest this, however. (Irrational numbers are discovered around 2,500 years ago.)
makendo pisze:
? 2026/5/24 14:42, Chris M. Thomasson ??:
On 5/23/2026 5:44 AM, fir wrote:
Chris M. Thomasson pisze:
On 5/22/2026 4:54 AM, fir wrote:
[...]
THATS A PROOF - radians suck (and should be thrown out both c and >>>>>> math)
Huh? Wow. That's a bold statement. I use radians all the damn time!
How many degrees is pi / 2 ?
degrees are less bad but also bad so dont ask how many degress but
maybe
how in this natural measure is what is "pi/2" in radians... its 0.25
as 2*pi ~ 1.0
pi/2? Oh man, you know!
I guess fir has a religious hatred of irrational numbers, so much that
their mind will have to twist reality when these are really needed.
By a similar logic, we should also nuke sqrt(3), exp(3) and log(3) from
C and math, because these generate a shit ton of irrational numbers.
Even Roman mathematicians from around 2,000 years ago will treat me as
a fool when I suggest this, however. (Irrational numbers are discovered
around 2,500 years ago.)
you know i was recently thinking of that somewhat and i dont get any
final thoughts but i get somewhat suspicious to e
you know how transformation from r, t (where r is radius and t is angle counted in 0..1 looks like
ÿxy = r*535.16 ^ I*t
really, check it
float complex rt2C(float r, float t)
{
ÿÿÿ return r*cpowf(535.49164f, I*t);
}
float2 rt2xy(float r, float t)
{
ÿreturn (float2) {r*cosf(t*6.2831855f),ÿÿÿ r*sinf(t*6.2831855f)};
}
(Irrational numbers are discovered around 2,500 years ago.)
On Sun, 24 May 2026 15:57:38 +0800, makendo wrote:
(Irrational numbers are discovered around 2,500 years ago.)
The Pythagoreans were horrified by the discovery. They saw it as some
kind of defect in the perfection of mathematics, and therefore of
reality, itself.
They tried to cover it up. One story is that the mathematician
Hippasus was killed to keep him from revealing the secret.
On Sun, 24 May 2026 15:57:38 +0800, makendo wrote:
(Irrational numbers are discovered around 2,500 years ago.)
The Pythagoreans were horrified by the discovery. They saw it as some
kind of defect in the perfection of mathematics, and therefore of
reality, itself.
They tried to cover it up. One story is that the mathematician
Hippasus was killed to keep him from revealing the secret.
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