Algorithm Definition and 651 Threads

  1. S

    What Does the Risch Algorithm Solve in Mathematics?

    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...
  2. Ƒ

    Comp Sci Solving Twin Primes with a Sieve Algorithm in Fortran

    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...
  3. H

    How Does the Euclidean Algorithm Scale with Multiplication Factors?

    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.
  4. O

    An algorithm for numerical double integration over non-rectangular regions.

    is there one that is stable and accurate?
    • okkvlt
    • Thread
    • Algorithm Integration Numerical
    • Replies: 1
    • Forum: Calculus
  5. H

    Algorithm to find out whether an input is a prime number or not

    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
  6. I

    Java What's wrong with my sorted linked list algorithm? (Java)

    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...
  7. M

    How Is the MD5 Hash Algorithm Calculated?

    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...
  8. A

    Metropolis-Monte Carlo Algorithm

    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...
  9. O

    Engineering Nodal analysis algorithm applied to a circuit without voltage sources

    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...
  10. P

    Division algorithm and unique Gaussian integers

    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...
  11. R

    Euclidean Algorithm: Solving x-1 = (x^3-x^2+2x-2)-(x+1)(x^2-2x+1)

    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 =...
  12. J

    Uncovering Hidden Treasures: 3 IIT Students' Primality-Test Algorithm

    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...
  13. N

    Understanding the Time Complexity of Nested Loops in Algorithms

    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...
  14. W

    Why lanczos algorithm is useful for finding the ground state energy?

    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
  15. Saladsamurai

    Need Help Developing Algorithm to Decode MathML

    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>...
  16. C

    Simulating relativity in a velocity verlet algorithm

    (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...
  17. O

    How Does Choosing Ball Subsets Affect Their Weight Growth in an Algorithm?

    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...
  18. C

    F4 algorithm for calculating Groebner bases

    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...
  19. J

    Why Does RSA Encryption Return the Original Number?

    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 =...
  20. B

    What exactly is a Parallel Algorithm ?

    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.
  21. M

    Is There a Problem With No Asymptotically Optimal Algorithm?

    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...
  22. D

    No Fastest Algorithm: Examples & Explanation

    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?
  23. C

    Simple Hex Multiplication question from AES Algorithm

    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...
  24. N

    Smoothing algorithm for times series and slope measurement

    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...
  25. A

    How Are Euclidean Algorithm and Hensel's Lemma Applied to Congruences?

    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...
  26. K

    Help with design of lift algorithm

    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
  27. R

    Can Music Notes Be Transformed into Mathematical Algorithms?

    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?
  28. K

    Finding Solutions for x12+x22=1 on Finite Fields Zp using Prime Number Algorithm

    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...
  29. Z

    An small question about RSA algorithm

    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.
  30. M

    What is the most optimal algorithm for playing a popular guessing game?

    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...
  31. K

    Sorting Pages in QuarkXPress: A Constrained Approach

    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...
  32. G

    Grover's Algorithm: is it really a search algorithm

    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...
  33. M

    The algorithm used by Google Maps?

    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...
  34. S

    Algorithm for prime factorization

    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...
  35. Pythagorean

    Ethod or algorithm that will always win in chess

    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)...
  36. S

    C/C++ Problem in c++ in writing an algorithm

    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...
  37. S

    Greedy Algorithm for license purchase problem

    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...
  38. R

    How can I improve convergence for my complex mathematical model?

    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...
  39. S

    Developing an Algorithm for Predicting Robot Position Over Time

    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...
    • ShowDown
    • Thread
    • Algorithm Position Robot Time
    • Replies: 2
    • Forum: Mechanics
  40. F

    What is the algorithm for generating numbers based on a given input?

    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...
  41. G

    Finding the recurrence from an algorithm

    I need some help. I am having a hard time find the recurrence when given an algorithm in c++. The algorithm is a Max search: Its where the program goes through the array from first element to last, or last to first (depends on how you program it) to look for the largest value. In this case it...
  42. S

    Mathematica Help with Prim's Algorithm in Mathematica

    This is my project of Spanning Tree by using Prim's Algorithm , I have to implies this problem (#4, PIC is attached) into Mathematica ( I have version 6 btw). Which we never learned in class. Its my Applied Math class, all we do/did is theorems. We never learned a single thing about this program...
  43. I

    Langevin dynamics random force term generation algorithm

    Hi, Can anyone tell me an algorithm to generate the stationary Gaussian distribution R(t) with \langle R(t) \rangle = 0 (zero mean) \langle R(t) R(t')^{T} \rangle = A \delta(t-t') , A = 2 \gamma k_B T m (autocorrelation) ? What I just wrote is from the Wikipedia article "Langevin...
  44. E

    Many-Body Numeric Integration Algorithm

    That is to say, how does one go about it for a non-separable partial differential equation? Let me preface by saying that I am not asking for an answer of perturbation theory, variational theory, mean-field theory, or some sort of self-consistent guess-and-check method (i.e., coupled...
  45. I

    How to accelerate the SVD algorithm?

    I've written a program in c language in terms of the GR SVD algorithm. To my dispointment,its performance is worse than the svd of matlab. I wish to get to know which algorithm the MATLAB used. Who may tell me? Thanks.
  46. S

    Testing a Lanczos (tridiagonalization) algorithm

    So I implemented a tridiagonalization algorithm, however I don't know if the result that I am receiving is accurate. Does anyone know of an easy way of testing this? I suppose it is possible to scour around for code, but it would be difficult to find matching code. So if anyone knows anything...
  47. D

    Grover's algorithm on entangled states

    If you run Grover's algorithm on the first qubit of any of the Bell states, does it destroy the entanglement? If not, wouldn't it be a way to communicate faster than light?
  48. C

    Regarding Floyd's cycle-finding algorithm

    Well I understand what is happening - the tortoise moving 1 step, and the hare moving 2 steps and finally coinciding at a point. But I want a mathematical proof of this - ie; when you have 2 counters moving in a cycle, one going 1 step, the other 2 steps, then they finally meet at a point.
  49. A

    Help in Explaining POSIT algorithm (3D maths)

    Hello Everyone, This is my fisrt post! I have been suggested that this forum's members may be able to help me, this thread was orginially posted in another forum, they have re-directed me towards this community! : {original post} Hi guys, I've been doing some background hobby...
  50. C

    C/C++ Solving Error in C++ Digit Algorithm Program

    I wrote a program to find the number of digits of an integer, but I always get the wrong result. Could someone point out the error? Here's the source code: #include <iostream> #include <cmath> using namespace std; int main() { int i=53443; cout<<log(i); return 0; }...