[ESPResSo-users] Angle potential 3-body vs 2-body (?) forces

[Memet, Edvin]

Dear all,

In a file like angle_cosine.hpp, for instance, what is the difference 
between the following functions?

inline int calc_angle_cosine_force(...)
inline void calc_angle_cosine_3body_forces(...)

The first one seems like it computes the forces on only two of the 
particles rather than on all three particles composing the angle bond. 
If that is the case, then why/how would that work?

Also, I've tried to check which of the two functions is actually being 
called when I define an angle potential. Surprisingly, it seemed like 
only the first function was being called. Is that correct? Is the force 
on the third particle zero, then, or is it being computed elsewhere?

If it's better to ask this in the developer's list, please let me know.

Best,
Edvin

angle_cosine.hpp
Description: angle_cosine.hpp