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arXiv · 1808.05009

Fast algorithm for generating random bit strings and multispin coding for directed percolation

Hiroshi Watanabe·Satoshi Morita·Synge Todo·Naoki Kawashima
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Abstract

We present efficient algorithms to generate a bit string in which each bit is set with arbitrary probability. By adopting a hybrid algorithm, i.e., a finite-bit density approximation with correction techniques, we achieve 3.8 times faster random bit generation than the simple algorithm for the 32-bit case and 6.8 times faster for the 64-bit case. Employing the developed algorithm, we apply the multispin coding technique to one-dimensional bond-directed percolation. The simulations are accelerated by up to a factor of 14 compared with an optimized scalar implementation. The random bit string generation algorithm proposed here is applicable to general Monte Carlo methods.

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Hiroshi Watanabe, Satoshi Morita, Synge Todo, Naoki Kawashima. 2018-08-15. Fast algorithm for generating random bit strings and multispin coding for directed percolation. https://doi.org/10.7566/jpsj.88.024004

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