Algorithm Definition and 724 Threads

Hi, I have the problema of implementing wolff's algorithm for ising model in 2-D lattice. Has anyone ever done this algorithm in FORTRAN ? I have questions of how to join the clusters. Alexandre

hi, this is my first post on this site so please excuse me (and correct me) if i am not posting according to the guidelines. im studying right now linear transformations and I am a bit shaky concerning dual vector spaces. i understand the definition but am not sure how to apply it. what...

Risch Algorithm? Hi all, Lately i came across an indefinite integral, and among its solutions one was using Risch Algorithm. However, the solution was not in detail, it was more of an outline, so i was curious to find out more about this algorithm which allows one to find the antiderivative...

Homework Statement I have been trying to come up with a program to calculate twin primes using a sieve algorithm in Fortran. So far I have been successful in creating one that finds primes, but I am having difficulty finding one that finds prime twins. If I knew how to do this I could find...

Prove that the number of steps of the euclidean algorithm needed to find gcd(km,kn) is exactly the same as the number of steps needed to find gcd(m,n). any help on this would be appreciated. I'm really lost.

is there one that is stable and accurate?

Homework Statement Suppose a weighted connected graph G = (V,E) has n edges. Describe an algorithm to find a Minimum Spanning Tree of G in O(n) time. Prove the correctness of your answer. (Here n = |V |). Homework Equations I know about DFS, BFS, Prims algorithm The Attempt at a...

Homework Statement 1- write an algorithm to find out whether an input is a prime number or not. 2-write aa program to compute square root by Newton method 3-write an algorithm to show an input is perfect or not. 4- Homework Equations The Attempt at a Solution

For a class project, I need to make an application that, among other things, can sort students in a class into project teams that takes students' schedules into consideration and groups students with overlapping schedules together. The way I'm storing schedule data is a collection of times...

So my algorithm compares a node that needs to be inserted with the current linked list set. it goes from first (which contains the lowest integer) and moves forward until it hits null or when the key trying to be inserted is no longer greater than the nodes being compared to. My input of 23...

Hi. I'm studying the cryptography MD5 calculation and have some trouble I'd like to seek help with. I am trying to comprehend the MD5 memo http://www.ietf.org/rfc/rfc1321.txt" and have trouble understanding the calculation. Here is what I comprehend so far. A message is appended with a 1...

This could be a well-known problem, but I looked around and I don't see anything. Suppose there is a set of points p_1, p_2, ... p_N. For simplicity, assume Euclidean space of arbitrary dimensionality, but this could be any metric space. I need to find a new set q_1, q_2, ... q_n of n...

peace upon you every body i spent few minutes searching where to post my topic .. because it's talking about something in computational physics and i found no forum for computational physics or things like that. so if you don't mind opening new forum for computational physics and i can offer...

hello there. this is as much a comp sci question as a physics question, however the comp sci board looked more like a 'computer technology' board, and didn't have much stuff relevant to physics. even though I'm trying to optimize an algorithm for a very specific need, it requires knowledge of...

Homework Statement Calculate the operating temperature for a flash unit. osf_2= 0.9 P = 750 mmHg f_1=30, A_1=15.9, B_1=2788.5, C_1=-52.3 f_2=50, A_2=16.0, B_2=3096.5, C_2=-53.7 f_3=40, A_3=16.1, B_3=3096.5, C_3=-59.4 T_{guess} = 400K calculate...

Homework Statement I am having some trouble with the nodal analysis algorithm explained in this web page http://www.swarthmore.edu/NatSci/echeeve1/Ref/mna/MNA3.html My electrical circuits knowledge is very basic, and I need to get the equivalent resistance of a circuit for a non related...

Homework Statement Theorem Let \alpha\neq0 and \beta be Gaussian integers. Then there are Gaussian integers \tau and \rho such that \beta=\tau\alpha+\rho and N\left(\rho\right)<N\left(\alpha\right) Problem Show that the Guassian integers \tau and \rho in the Theorem are unique if and only...

Homework Statement The following is a worked example, I circled around the part which I couldn't follow: http://img15.imageshack.us/img15/161/untitleou.jpg Homework Equations The Attempt at a Solution To begin with, I can't understand why they wrote: x-1 =...

This is an old news, but isn't it impressive? 3 IIT undergrad students discovered a newer algorithm for primality-tests-of-an-integer as part of their undergrad student project. That even using some centuries old well known formula and just high school mathematics. Wondering how many such low...

Ok, I am brand new at this so I am kind of confused how to figure this out. i \leftarrow n while i >= 1 j \leftarrow i while j <= n <body of the j loop>, needs (1) j \leftarrowj*2 end j while i \leftarrowi-1 end i while I know that with nested...

i am now reading some materials on lanczos algorithm, one of the ten most important numerical algorithms in the 20th century my puzzle is, why it is useful for finding out the ground state energy? i can not see anything special about the ground state energy in the algorithm

Yeah. I know it is going to be a pain. But I need to do it for work. If you are not familiar with MathML, it is similar to LaTeX. Here is an example: The expression x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}would me represented in MathML as <mrow> <mi>x</mi> <mo>=</mo> <mfrac>...

(Skip to the * mark if you would like to see my question without the background) Hi, I'm trying to write a turn-based computer game which simulates space combat at relativistic speeds, but I'm a beginner at programming and I don't know much physics beyond the high school level. The game...

there are n balls of weight 1/n. an opponent choose each time a subset of balls that each one has weight less than 1. then each ball in this set, its weight is multiplied by 1+\frac{1}{|S|} where S is the set of balls that the opponent chose. I need to show that for each choice of subsets...

Dear all, I have a question concerning Faugere's improved F4 algorithm. You can find it in the attached file faugere_f4.pdf on page 9. In section 2.6 (page 14) an example is given for how the algorithm works. According to the example the second while-loop in the improved F4 algorithm...

Hey guys, After taking linear algebra I decided I could try my hand at learning some introductory QC algorithms, and downloading this introductory paper from arxiv: http://arxiv.org/abs/quant-ph/0301079v1 After mulling through it for a couple of days, I got a little disturbed by their...

Struggling to put a number through this as I keep getting my original number as the encrypted number too. A = 11 p = 3 q = 5 n = pq = 15 z = (p-1)(q-1) = 2*4 = 8 k = co-prime of z = 7 So, A=11 n=15 z=8 (Public key) k=7(Public key) kj = 1 (mod z) 7j = 1 (mod 8) for which I am getting j =...

What exactly is a "Parallel Algorithm"? I understand what parallel algorithms are intended to do, but I do not know what they are used for.

Homework Statement I am trying to write a pseudocoded recursive algorithm. Algorithm is located @: http://gameprogrammer.com/fractal.html#diamond" I am getting the ending wrong. Homework Equations Do diamond step. Do square step. Reduce random number range. Call myself...

I was just wondering. Is there a computational problem P for which there is no asymptotically least-time solution? In other words: let x be an algorithm which is a solution to P. Denote by T(x), the worst-case runtime of x as a function of its input size. Is it possible that for any...

It has been conjectured that there is no fastest algorithm for multiplication, among other things. Can somebody give me an example of something that provably has no fastest algorithm for?

I searched around a while on the site to see if I could find a thread that could answer this question and was unable to find one. If this has already been asked before, I apologize. I'm having a problem with something in the AES crypto algorithm...

Hi, I'm doing an experiment that gathers one data point approximately each second. I have plotted all the datapoints on a graph. The graph has many tops and bottoms. Now due to the fact that there are so many data points and that I can visualle tell that there are several overal trends: one...

1)5x=1(16) is equivalent to x=5(6) is equivalent to x=1(2), x=2(3) <the equal sign here i mean congruence to> i'm a bit confused about the equivalence...how this is so? 2)3k-7n=1, k,n integers by using euclidean algorithm i got k=-2, n=-1. but the answer i got here is k=5, n=2 (the...

Hi there, i am working on a lift algorithm and i don't know how to implement it. can anyone pls code the program for me in ANSI C? i will be grateful for the favour. regards kautilya

I have heard that it is possible to convert music notes into mathematical numbers. To create an algorithm, can you use musical notes, or patterns?

i am sorry guys, the last time i posted this problem it was completely different but this time if we Let x12+x22=1 be a unit circle upon a finite field Zp where p is prime. Is there any algorithm which can give all the possible solutions (x1,x2) an element of Zp*Zp as well as the total number of...

on the RSA algorithm http://en.wikipedia.org/wiki/RSA why simply we can not choose e=1 or e=2 ? it would simplify the calculations a lot.

I need to come up with an optimal algorithm for playing a popular guessing game which you might know by a handful of names like Bulls and Cows, Codebreaker, Guess-the-number, Mastermind(without repeating digits though). Here's the general definitions from the wiki page: I have thought about...

Hi I have a sorting problem I haven't been able to solve and was hoping someone here could lend some insights. The basic problem is resorting pages in a page layout application (QuarkXPress) where I'm constrained to only the functions Quark supplies for moving pages around in a document...

I'm wondering how it really is useful. The input for the, say 2-qubit, quantum computer that is running Grover's algoritm is |\Psi \rangle = (|1 \rangle + |2 \rangle + |3 \rangle + |4 \rangle) / \sqrt{4} And let us say we're looking the 3rd element in the so-called database. Now, Grover...

I was using at Google Earth, and used it to look at some directions when I noticed that program recommended that I take a right and drive down this road, then take a u-turn and drive past from where I turned originally, when I could've just simply taken a left instead. Does anyone know how...

Homework Statement One algorithm for finding the prime factorization of a number n is the following: Starting with d = 2, and continuing until n\geqd, try to divide n by d. If n/d, then record d as a (prime) factor and replace n by n/d; otherwise replace d by d + 1. a) When d is recorded...

I have a simulation with a satellite that orbits Earth in 3d. Earth's shadow, for simplification purposes (the satellite is pretty close to earth) is either on or off. There's no light diffraction here. It can be represented as a cylinder with radius ~6378km, and an axis which aligns with...

is there a method or algorithm that will always win in chess or can the algorithm/method always be fooled by the choices of the opponent? I know for a while there was a lot of noise over Big Blue, but I'm curious where the subject sits today. In all the games I play (i.e. amateur games)...

Hello, please help me to find the problem in algorithm. My task is to read from file hotel visitor's info (name/surname, date of arrival, date of departure, room number). Than, to contract similar room numbers and write near the overall number of days in particular room. So everything is good...

Your friends are starting a security company that needs to obtain licenses for n different pieces of cryptographic software. Due to regulations, they can only obtain these licenses at the rate of at most one per month. Each license is currently selling for a price of $100. However, they are...

I have a complex mathematical model (about 2000 lines of code) which calculates heat exchanger performance. Using Q=UxAxLMTD I want to iterate the entering temperature until I find that the installed surface satisfies a target duty. At present I 1 guess an entering temperature and from...

Hello everyone, I am a researcher for a robotic soccer project, and I am developing a guidance algorithm in which I need to be able to predict the position of our robots over time, given only that they have a constant acceleration. These are omnidirectional wheeled robots, which means they...

I read the rules of the site and read the stickies, I hope this is in the right section. I need help figuring out this algorithm, putting a number in generates the corresponding numbers. Sorry if the post is long, I tried to get as much information as possible. I can enter any number that...