Regarding fix/setforce and "atom" style variable command

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1

Hello All,

For fix/setforce command, the documentation says that ““This fix computes a global 3 vector of forces, which is a total force on the group of atoms BEFORE the forces on individual atoms are changed by this fix””.

Also, “atom” style variable stores peratom quantities.

Thus here is my question::–> If i use the following commands-

fix 1 all nve

fix 2 mobile temp/rescale 1.0 10.0 10.0 2.0 1.0

fix 3 upper setforce 0.0 0.0 0.0

variable force_upper atom f_3[1]

Then should i expect that value of force_upper will be the ““Total force on the upper region in x-direction after operation of ‘fix 2’/Total atoms in the upper region””.??

Thanks

Sagar

2

Hello All,

For fix/setforce command, the documentation says that ""This fix computes a
global 3 vector of forces, which is a total force on the group of atoms
BEFORE the forces on individual atoms are changed by this fix"".

Also, "atom" style variable stores peratom quantities.

Thus here is my question::--> If i use the following commands-

fix 1 all nve
fix 2 mobile temp/rescale 1.0 10.0 10.0 2.0 1.0
fix 3 upper setforce 0.0 0.0 0.0

variable force_upper atom f_3[1]

Then should i expect that value of force_upper will be the ""Total force on
the upper region in x-direction after operation of 'fix 2'/Total atoms in
the upper region"".??

this kind of question you can easily answer yourself by building a
small test input and dumping forces and fix info to a dump file.

axel.