calculating an arbitrary summation

Hello everyone

I want to calculate sum_i{sum_j(r_ij*f_ij)} where all i and j atoms belong to the same group G. This means, among all the neighbors of an atom i, only those j atoms should be used in the summation that belong to group G.

Dose anyone has any idea how I could calculate it?

thank you in advance for your time

best regards,

Abolfalz

Hello everyone

I want to calculate *sum_i{sum_j(r_ij*f_ij)} *where all i and j atoms
belong to the same group G. This means, among all the neighbors of an atom
i, *only *those j atoms should be used in the summation that belong to
group G.

Dose anyone has any idea how I could calculate it?

​i don't think, that there is a ready-to-use feature for that. you'll have
to program it in C++​ as a custom compute style.

​axel.​

thanks dear Axel.