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### compute coord/atom command

Syntax:

    compute ID group-ID coord/atom cutoff

- ID, group-ID are documented in compute command
- coord/atom = style name of this compute command
- cutoff = distance within which to count coordination neighbors (distance units)

Examples:

    compute 1 all coord/atom 2.0

Description:

Define a computation that calculates the coordination number for each atom in a group.

The value of the coordination number will be 0.0 for atoms not in the specified compute group.

The coordination number is defined as the number of neighbor atoms within the specified cutoff distance from the central atom. Atoms not in the group are included in the coordination number of atoms in the group.

The neighbor list needed to compute this quantity is constructed each time the calculation is performed (i.e. each time a snapshot of atoms is dumped). Thus it can be inefficient to compute/dump this quantity too frequently or to have multiple compute/dump commands, each of a coord/atom style.

Output info:

This compute calculates a per-atom vector, which can be accessed by any command that uses per-atom values from a compute as input. See Section_howto 15 for an overview of LAMMPS output options.

The per-atom vector values will be a number >= 0.0, as explained above.

Restrictions: none

Related commands:

compute cluster/atom

Default: none