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d-meiser / cold-atoms

A tool box for cold-atom simulations.
GNU General Public License v3.0
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Add softcore cutoff to Coulomb force. #10

Closed d-meiser closed 7 years ago

d-meiser commented 7 years ago

This allows us to set a limit to the Coulomb force which can be necessary to make naive integrators of the particle motion stable. Without such a cutoff the Coulomb force can become arbitrarily large leading to accuracy and stability issues in most integrators.

We bound the softcore radius from below by an amount that is designed to work well with finite floating point precision. This allows us to get rid of the check for identical particles in the force computation loop.

coveralls commented 7 years ago

Coverage Status

Coverage increased (+0.05%) to 96.97% when pulling dfb2bf9e8f93a49d94bf699f12fd9e3f846209f1 on add-cutoff-parameter-#8 into 21d2e80552f4f6d6b0d2dac656e3c66a168a280b on master.

coveralls commented 7 years ago

Coverage Status

Coverage increased (+0.05%) to 96.97% when pulling dfb2bf9e8f93a49d94bf699f12fd9e3f846209f1 on add-cutoff-parameter-#8 into 21d2e80552f4f6d6b0d2dac656e3c66a168a280b on master.