What is the variable of PE in lammps C++ files?

Hi steve and all,

I want to modify a FIX command so I‘m adding some codes into its .cpp file. But I cannot find the right variable representing the potential energy “pe”.
As I know, the positions of atoms are represented by a array named by X[i][j], where i is the number of “nlocal”, and the j means the three vector of axes.
So, which variable in c++ files represents the potential energy?
Thanks and best wishes.

If you want to write a fix that contributes to the potential
energy of the system, then look at fix indent, which does this.
Also see the fix indent doc page which explains this is done
via the fix_modify energy option which calls a method inside
the fix (from compute_pe.cpp) and modify->thermo_energy()
to retrieve the contribution from the fix.

Steve