101–110 of 317 posts
Earlier quoted context omitted.
Are you under the impression that CPUs are made exclusively from NAND gates? You can't be serious.
Might’ve gotten mixed up with CMOS dominance, or I’m ignorant.
This makes a good benchmark LLMs: ``` look at this paper: https://arxiv.org/pdf/2603.21852 now please produce 2x+y as a composition on EMLs ``` Opus(paid) - claimed that "2" is circular. Once I told it that ChatGPT have already done this, finished successfully. ChatGPT(free) - did it from the first try. Grok - produced estimation of the depth of the formula. Gemini - success Deepseek - Assumed some pre-existing knowl…
It got a result.
Earlier quoted context omitted.
They are done with transistors though. Transistors form an efficient, single element, universal digital basis. And are a much less arbitrary choice than NAND, vs. NOR, XOR, etc. Using transistors as conceptual digital logic primitives, where power dissipation isn't a thing, Pass Logic is "The Way".
Single transistors aren't yet logic gates by themselves; they are amplifiers with a very specific gain function that makes it possible to use them as switches. Logic gates usually consist of at least two transistors. See https://en.wikipedia.org/wiki/CMOS for an example of how it is done in CMOS technology.
Pass logic. Digital. [0]
This is extremely basic digital circuit design. You can create digital circuits as compositions of gates. But you can often implement the same logic, with fewer transistors, using pass logic.
Pass logic is also great for asynchronous digital design.
nix run github:pveierland/eml-eval
EML Evaluator — eml(x, y) = exp(x) - ln(y)
Based on arXiv:2603.21852v2 by A. Odrzywołek
Constants
------------------------------------------------------------------------------
1 K=1 d=0 got 1 expected 1 sym=ok num=ok [simplify]
e K=3 d=1 got 2.718281828 expected 2.718281828 sym=ok num=ok [simplify]
0 K=7 d=3 got 0 expected 0 sym=ok num=ok [simplify]
-1 K=17 d=7 got -1 expected -1 sym=ok num=ok [simplify]
2 K=27 d=9 got 2 expected 2 sym=ok num=ok [simplify]
-2 K=43 d=11 got -2 expected -2 sym=ok num=ok [simplify]
1/2 K=51 d=15 got 0.5 expected 0.5 sym=ok num=ok [simplify]
-1/2 K=67 d=17 got -0.5 expected -0.5 sym=ok num=ok [simplify]
2/3 K=103 d=19 got 0.6666666667 expected 0.6666666667 sym=ok num=ok [simplify]
-2/3 K=119 d=21 got -0.6666666667 expected -0.6666666667 sym=ok num=ok [simplify]
sqrt2 K=85 d=21 got 1.414213562 expected 1.414213562 sym=ok num=ok [simplify]
i K=75 d=19 got i expected i sym=ok num=ok [i²=-1, simplify]
pi K=153 d=29 got 3.141592654 expected 3.141592654 sym=ok num=ok [simplify]
Unary functions (x = 7/3)
------------------------------------------------------------------------------
exp(x) K=3 d=1 got 10.3122585 expected 10.3122585 sym=ok num=ok [simplify]
ln(x) K=7 d=3 got 0.8472978604 expected 0.8472978604 sym=ok num=ok [simplify]
-x K=17 d=7 got -2.333333333 expected -2.333333333 sym=ok num=ok [simplify]
1/x K=25 d=8 got 0.4285714286 expected 0.4285714286 sym=ok num=ok [simplify]
x - 1 K=11 d=4 got 1.333333333 expected 1.333333333 sym=ok num=ok [simplify]
x + 1 K=27 d=9 got 3.333333333 expected 3.333333333 sym=ok num=ok [simplify]
2x K=67 d=17 got 4.666666667 expected 4.666666667 sym=ok num=ok [simplify]
x/2 K=51 d=15 got 1.166666667 expected 1.166666667 sym=ok num=ok [simplify]
x^2 K=41 d=10 got 5.444444444 expected 5.444444444 sym=ok num=ok [simplify]
sqrt(x) K=59 d=16 got 1.527525232 expected 1.527525232 sym=ok num=ok [simplify]
Binary operations (x = 7/3, y = 5/2)
------------------------------------------------------------------------------
x + y K=27 d=9 got 4.833333333 expected 4.833333333 sym=ok num=ok [simplify]
x - y K=11 d=4 got -0.1666666667 expected -0.1666666667 sym=ok num=ok [simplify]
x * y K=41 d=10 got 5.833333333 expected 5.833333333 sym=ok num=ok [simplify]
x / y K=25 d=8 got 0.9333333333 expected 0.9333333333 sym=ok num=ok [simplify]
x ^ y K=49 d=12 got 8.316526261 expected 8.316526261 sym=ok num=ok [simplify]Earlier quoted context omitted.
ah, the paper acknowledges this. my bad for jumping to the diagrams!
On page 11, the paper explicitly states: > EML-compiled formulas work flawlessly in symbolic Mathematica and IEEE754 floating-point… This is because some formulas internally might rely on the following properties of extended reals: ln 0 = −∞, e^(−∞) = 0. And then follows with: > But EML expressions in general do not work ‘out of the box’ in pure Python/Julia or numerical Mathematica. Thus, the paper’s completeness cl…
This is the standard convention when doing operations in the extended real number line, i.e. in the set of the real numbers completed with positive and negative infinities.
When the overflow exception is disabled, any modern CPU implements the operations with floating-point numbers as operations in the extended real number line.
So in computing this convention has been standard for more than 40 years, while in mathematics it has been standard for a couple of centuries or so.
As always in mathematics, when computing expressions, i.e. when computing any kind of function, you must be aware very well which are the sets within which you operate.
If you work with real numbers (i.e. in a computer you enable the FP overflow exception), then ln(0) is undefined. However, if you work with the extended real number line, which is actually the default setting in most current programming languages, then ln(0) is well defined and it is -∞.
Earlier quoted context omitted.
> Why use splines or polynomials or haphazardly chosen basis functions if you can just fit (gradient descent) your data or wave functions to the proper computational EML tree? Same reason all boolean logic isn't performed with combinations of NAND – it's computationally inefficient. Polynomials are (for their expressivity) very quick to compute.
They are done with transistors though. Transistors form an efficient, single element, universal digital basis. And are a much less arbitrary choice than NAND, vs. NOR, XOR, etc. Using transistors as conceptual digital logic primitives, where power dissipation isn't a thing, Pass Logic is "The Way".
But transistors can be N or P-channel, so it’s not a single logical primitive, like e.g. NAND-gates.
Not sure it really compares to NAND() and the likes. Simply because bool algebra doesn't have that many functions and all of them are very simple to implement. A complex bool function made out of NANDs (or the likes) is little more complex than the same made out of the other operators. Implementing even simple real functions out of eml() seems to me to add a lot of computational complexity even with both exp() and ln…
Reminds me a bit of the coolest talk I ever got to see in person: https://youtu.be/FITJMJjASUs?si=Fx4hmo77A62zHqzy It’s a derivation of the Y combinator from ruby lambdas
Have you gone through The Little Schemer ? More on topic: > No comparable primitive has been known for continuous mathematics: computing elementary functions such as sin, cos, sqrt, and log has always required multiple distinct operations. I was taught that these were all hypergeometric functions. What distinction is being drawn here?
When you have a function with many parameters it becomes rather trivial to express simpler functions with it.
You could find a lot of functions with 4 parameters that can express all elementary functions.
Finding a binary operation that can do this, like in TFA, is far more difficult, which is why it has not been done before.
A function with 4 parameters can actually express not only any elementary function, but an infinity of functions with 3 parameters, e.g. by using the 4th parameter to encode an identifier for the function that must be computed.
Is the the same as saying everything can be made from nand gates?
This work is about continuous systems, even if the reduction of many kinds of functions to compositions of a single kind of function is analogous to the reductions of logic functions to composing a few kinds or a single kind of logic functions.
I actually do not value the fact that the logic functions can be expressed using only NAND. For understanding logic functions it is much more important to understand that they can be expressed using either only AND and NOT, or only OR and NOT, or only XOR and AND (i.e. addition and multiplication modulo 2).
Using just NAND or just NOR is a trick that does not provide any useful extra information. There are many things, including classes of mathematical functions or instruction sets for computers, which can be implemented using a small number of really independent primitives.
In most or all such cases, after you arrive to the small set of maximally simple and independent primitives, you can reduce them to only one primitive.
However that one primitive is not a simpler primitive, but it is a more complex one, which can do everything that the maximally simple primitives can do, and it can recreate those primitives by composition with itself.
Because of its higher complexity, it does not actually simplify anything. Moreover, generating the simpler primitives by composing the more complex primitive with itself leads to redundancies, if implemented thus in hardware.
This is a nice trick, but like I have said, it does not improve in any way the understanding of that domain or its practical implementations in comparison with thinking in terms of the multiple simpler primitives.
For instance, one could take a CMOS NAND gate as the basis for implementing a digital circuit, but you understand better how the CMOS logic actually works when you understand that actually the AND function and the NOT function are localized in distinct parts of that CMOS NAND gate. This understanding is necessary when you have to design other gates for a gate library, because even if using a single kind of gate is possible, the performance of this approach is quite sub-optimal, so you almost always you have to design separately, e.g. a XOR gate, instead of making it from NAND gates or NOR gates.
In CMOS logic, NAND gates and NOR gates happen to be the simplest gates that can restore at output the same logic levels that are used at input. This confuses some people to think that they are the simplest CMOS gates, but they are not the simplest gates when you remove the constraint of restoring the logic levels. This is why you can make more complex logic gates, e.g. XOR gates or AND-OR-INVERT gates, which are simpler than they would be if you made them from distinct NAND gates or NOR gates.