[gmx-users] g_angle calculation

[SebastianWaltz]

Hi all,

I try to reproduce the results from g_angle using my own c++ code. Using
the formula

θ=acos(r_ij * r_kj/|r_ij||r_kj|)

with the acos from the cmath library, I obtain an angle which is always
~5% larger when the angel calculated by g_angle.
Does g_angle use the same formula or does it calculate θ in a different way?

All commands a very much welcomed

Sebastian