Abstract
This paper introduces the problem of floating-point rounding errors in physical simulation. A simple virtual creature is simulated in a physical environment for a specified number of time steps. The effect of rounding errors is illustrated by varying the initial position of the creature which causes a change in the fitness value computed by a simple distance-based fitness function. With a large evaluation time, these rounding errors can produce significantly large differences in fitness. A discussion is provided on the importance of this finding for evolutionary simulations, including suggestions to alleviate the problem.
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Acknowledgments
The authors would like to acknowledge and thank for the support of the Japan Society for the Promotion of Science (JSPS) through the JSPS Fellowship for Foreign Researchers and the JSPS Grant-in-Aid for Scientific Research.
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Pilat, M.L., Suzuki, R. & Arita, T. Dealing with rounding error problems in evolutionary physical simulation. Artif Life Robotics 17, 158–162 (2012). https://doi.org/10.1007/s10015-012-0038-0
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DOI: https://doi.org/10.1007/s10015-012-0038-0