Symplectic Integrator Mercury: Bug Report

K. de Souza Torres; D. R. Anderson

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arXiv · 0808.0483

Symplectic Integrator Mercury: Bug Report

K. de Souza Torres·D. R. Anderson

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Abstract

We report on a problem found in MERCURY, a hybrid symplectic integrator used for dynamical problems in Astronomy. The variable that keeps track of bodies' statuses is uninitialised, which can result in bodies disappearing from simulations in a non-physical manner. Some FORTRAN compilers implicitly initialise variables, preventing simulations from having this problem. With other compilers, simulations with a suitably large maximum number of bodies parameter value are also unaffected. Otherwise, the problem manifests at the first event after the integrator is started, whether from scratch or continuing a previously stopped simulation. Although the problem does not manifest in some conditions, explicitly initialising the variable solves the problem in a permanent and unconditional manner.

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K. de Souza Torres, D. R. Anderson. 2008-08-04. Symplectic Integrator Mercury: Bug Report. https://arxiv.org/abs/0808.0483

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