ZeroMomentum¶

class hoomd.md.update.ZeroMomentum(trigger)¶

Zeroes system momentum.

Parameters:: trigger (hoomd.trigger.trigger_like) – Select the timesteps to zero momentum.

ZeroMomentum computes the center of mass linear momentum of the system:

\[\vec{p} = \frac{1}{N_\mathrm{free,central}} \sum_{i \in \mathrm{free,central}} m_i \vec{v}_i\]

and removes it:

\[\vec{v}_i' = \vec{v}_i - \frac{\vec{p}}{m_i}\]

where the index \(i\) includes only free and central particles (and excludes consitutent particles of rigid bodies).

Note

ZeroMomentum executes on the CPU even when using a GPU device.

Examples:

zero_momentum = hoomd.md.update.ZeroMomentum(
    hoomd.trigger.Periodic(100)
)

Members inherited from AutotunedObject:

property is_tuning_complete¶: Check if kernel parameter tuning is complete. Read more...

Members inherited from Integrator: