Questions tagged [fixed-point]
The fixed-point tag has no usage guidance.
3
votes
1answer
32 views
Fixed point of hash
Are hashing algorithms constructed to guarantee that no fixed point exists?
My assumption is not, because I don’t see what utility that would have. (Please correct me if I’m wrong.) As such, purely ...
4
votes
1answer
136 views
Logical characterization of P versus NP problem (and references for least fixed point logic)
Wikipedia says the following (and more) about the logical characterization of the P versus NP problem here:
Thus, the question "is P a proper subset of NP" can be reformulated as "is existential ...
5
votes
2answers
532 views
Why Does the Fixed Point Theorem Apply to Quines?
A quine is a program that outputs its own source code without taking in any input. An example would be this (taken from here)
...
1
vote
1answer
583 views
How does conversion from fixed-point to floating-point happen?
I came across to the code that convert 32-bit signed fixed-point number (16.16) to a float and it looks like (pseudocode)
floating = fixed / 65536.0
Could you ...
1
vote
0answers
25 views
Hebbian rule doesn't get to a fixpoint
I'm trying to implement an Hopfield Network for pictures of 32x32 bits either 1 or -1;
I have these 3 pictures and I transform each of them in a vector of 1024 elements.
Then I take the 3 vectors and ...
1
vote
1answer
105 views
Is Datalog negation and the built-in predicate $ \neq $ similar?
I was reading "Principles of Database & Knowledge-Base Systems, Vol. 1" by Jeffrey D. Ullman. There is a chapter about Datalog negation and as I was seeing the problems of negation I kept thinking ...
1
vote
1answer
377 views
Neural Networks: Simulate the working of Dynamic Fixed Point representation of the weights on hardware
I am looking to implement a neural network on hardware using Verilog. I have completed and tested with floating point representation and a 20 bit fixed point representation. I want to further reduce ...
4
votes
2answers
177 views
What is a fixpoint?
Could someone please explain me, what is a fix point?
I caught the minimum explanation about fix point from the website:
After infinitely many iterations we should get to a fix point where
...
3
votes
1answer
58 views
Why doesn't this quine-less language contradict Kleene's recursion theorem?
Kleene's recursion theorem implies that every Turing complete programming language that satisfies certain properties have quines. This website claims that this is incorrect, and that there is a Turing ...
0
votes
2answers
300 views
Decimal to Fixed Point Conversion
I am having trouble to get the intuition behind the following approach:
We take the fraction point (say: .642) and continuously multiply by 2,
taking whatever ends up right of the point as our next ...
3
votes
2answers
44 views
Notation for a Kleene fixed point with a starting element
Assume a CPO $Q,\leq$ and a Scott-continuous function $f : Q \rightarrow Q$. As it is known, the chain $\bot \leq f(\bot) \leq \ldots \leq f^n(\bot)$ (where $f^n$ denotes the function $n-1$-times ...
10
votes
2answers
2k views
Why is least fixed point (lfp) important in program analysis
I am trying to get a big picture on the importance of least fixed point (lfp) in program analysis. For instance abstract interpretation seems to use the existence of lfp. Many research papers on ...
