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### compute erotate/asphere command

Syntax:

    compute ID group-ID erotate/asphere

- ID, group-ID are documented in compute command
- erotate/asphere = style name of this compute command

Examples:

    compute 1 all erotate/asphere

Description:

Define a computation that calculates the rotational kinetic energy of a group of aspherical particles.

The rotational kinetic energy is computed as 1/2 I w^2, where I is the inertia tensor for the aspherical particle and w is its angular velocity, which is computed from its angular momentum.

IMPORTANT NOTE: For 2d models, particles are treated as ellipsoids, not ellipses, meaning their moments of inertia will be the same as in 3d.

Output info:

The scalar value calculated by this compute is "extensive", meaning it it scales with the number of atoms in the simulation.

Restrictions:

This compute requires that particles be represented as extended ellipsoids and not point particles. This means they will have an angular momentum and a shape which is determined by the shape command.

This compute requires that atoms store angular momentum and a quaternion to represent their orientation, as defined by the atom_style. It also require they store a per-type shape. The particles cannot store a per-particle diameter or per-particle mass.

All particles in the group must be finite-size. They cannot be point particles, but they can be aspherical or spherical.

Related commands: none

compute erotate/sphere

Default: none