Reviewing the compute KE class

In this section, we'll study the methods implemented in the compute KE class, which calculates kinetic energy of a group of atoms.

The kinetic energy (KE) of an atom of mass m and linear velocity is calculated using the following equation:

The compute_ke.cpp class can be used to calculate the kinetic energy of a specified group of atoms. In a LAMMPS input script, the corresponding syntax is as follows:

compute  COMPUTE_ID  GROUP_ID  ke

As you can see, the COMPUTE_ID parameter is the unique ID of the compute defined, while the GROUP_ID parameter is the ID of the group of atoms that the compute acts on. This is described in detail in the LAMMPS manual (https://lammps.sandia.gov/doc/compute_ke.html). First, we will look at the constructor method, ComputeKE::ComputeKE(), of this class.

ComputeKE::ComputeKE()

This constructor method inherits from the Compute parent class (line 26) and checks the number...