Alias Walker and Walker Hasting Algorithm for O(1) symmetry (-1<S<1)

Spins with one components: S=x local field : hlocal=(hlocalx) Energy=-S.hlocal=-hlocal.x P(x)=e-Energy/T.dx        =eh.x.dx

The Alias Walker (AW) and Alias Walker Hasting (AWH) Algorithms use the rejection method with a function consisting of n steps (see the figure and article for more details)

Download the Alias Walker (AW) and Alias Walker Hasting (AWH) Algorithms:

	1.	To use the Alias Walker (AW) and Alias Walker Hasting (AWH) Algorithms you must have :
		O1_walker.c   (in C)
	2.	AND you must have the tables in the file "O1_walker.res". Two choices: . You can choose to download the file O1_walker.res already done or make one with create_O1_walker.out (.exe for windows), run it, and follow the instructions.
		O1_walker.res   (380 Ko) h -> [0,100[ with rate=70% or For LINUX, only one executable create_O1_walker.out   (For LINUX, 450 Ko) For WINDOWS copy these two programs in the same directory 1. create_O1_walker.exe   (For WINDOWS, 34 Ko) 2. cygwin1.dll   (For WINDOWS, 950 Ko) To get a very similar C Program for XY spins O2_Alias_Walker.html

Download the Article:

Article.pdf (440 Ko)

Probabilities and Performances :

Figure: comparison of the time of simulation for various algorithms (Alias Walker and Alias Walker Hasting, Metropolis,Me, Direct Heat Bath, DHB, and Fast Linear Algorithm, FLA) for the three dimensional antiferromagnetic triangular lattices (3t) The critical temperatures is shown by the squares The Fast Linear Algorithm (FLA) is the fastest of all algorithms proposed (2 times faster than the Metropolis Me, at the critical temperature in this case) and 25 to 40% faster than the Alias Walker algorithm and Alias Walker Hasting algorithm. More...

Other Algorithms in C

• Fast Linear Algorithm
• Other algorithms for O(1)
  • Direct Heath Bath (DHB)
  • Metropolis

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• go to ~loison/
• mail to D. Loison