[ESPResSo] variable and external force

[Hongjun Liu]

Dear all,
In LAMMPS, variable command can be used to define a variable that can be invoked in the script or in the simulation. I am wondering whether there is variable command or anything similar in the Espresso? Also in the feature of "EXTERNAL_FORCES", it says "define an arbitrary constant force for each particle individually". Can I use a variable to define a  changeable force on each particle? Thanks.

Best Regards,
Hongjun