Questions tagged [iterated-logarithm]
11 questions
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3 answers
25
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What does "log*" mean?
I have come across the term O(log* N) in a book I'm reading on data structures. What does log* mean? I cannot find it on Google, and WolframAlpha doesn't understand it either.
pauldoo
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Meaning of lg * N in Algorithmic Analysis
I'm currently reading about algorithmic analysis and I read that a certain algorithm (weighted quick union with path compression) is of order N + M lg * N. Apparently though this is linear because lg * N is a constant in this universe. What…
themaestro
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Which of the growth rates log(log *n) and log*(log n) is faster?
As n gets large, of the two functions log*(log n) and log(log* n) will will be faster?
Here, the log* function is the iterated logarithm, defined here:
I suspect these are the same, just written differently, but is there any difference between…
user97452
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Is there any algorithm with time complexity O(lg * n) (iterated logarithm function)?
In computer science, the iterated logarithm of n, written log* n (usually read "log star"), is the number of times the logarithm function must be iteratively applied before the result is less than or equal to 1. The simplest formal definition is the…
Naveen N
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Weighted quick-union with path compression algorithm: time complexity analysis
I'm learning "Weighted quick-union with path compression" algorithm for an union/find structure. The Princeton edu site explained detailedly the algorithm.
And here is the implementation in Java:
public class WQUPC {
private int[] id;
private…
pjpj
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1 answer
What is Time complexity of "set" and "if item in array" in Python?
I need to check if a number and its double exist in an array. This code using set to solve it. However I am not sure the Time complexity is better than O(N^2). I use the for loop and if 2*item in s like below. Isn't it to know whether the item is in…
Snow_Ball
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Big theta of iterative logarithm
I have two mathematical functions: log(log*n) and 2^(log*n).
Now, I want to calculate the asymptotic growth of these two functions(especially I want to find big theta). Finally, I want to compare their complexity. Can anyone please share a…
kayas
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Complexity of iterated logarithm on base 2
Assuming iterated logarithm is defined as it is here: http://en.wikipedia.org/wiki/Iterated_logarithm
How should I go about comparing its complexity to other functions, for example lg(lg(n))? So far I've done all the comparing by calculating the…
Sunny
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Iterated Logarithm in Prolog
log2(I,E):-
(
number(I)
-> E is log(I)/log(2);
number(E)
-> I is 2**E
).
lgstar(N,A):-
(N>1
->
(
log2(N,Nprev),
lgstar(Nprev,Aprev),
Aprev is A-1
);
A is 0
).
Log * is the number of times a…
Crinkley Crewms
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Iterated logarithm Big-O complexity
I have 2 doubts:-
1) Is (log* n)^n = O((logn)!) ?
2) Which is bigger, log(log* n) or log*(logn) ?
Zephyr
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