illegal fix move

Hi All,

I’ve been trying to implement a “fix move” and getting an error. I implemented a fix move linear over the group of atoms I was interested in, and it integrated fine. But I wanted to have the velocity of the group be a function of time, so I attempted to use a fix move variable command, but every attempt I’ve made has resulted in a “illegal fix move” command, with no clarification. Even the most basic fix move variable command is rejected (see below, where the group does not move).

fix 123 base move variable 0.0 0.0 0.0 0.0 0.0 0.0

Any thoughts?

-Emil

Hi All,

I’ve been trying to implement a “fix move” and getting an error. I
implemented a fix move linear over the group of atoms I was interested in,
and it integrated fine. But I wanted to have the velocity of the group be a
function of time, so I attempted to use a fix move variable command, but
every attempt I’ve made has resulted in a “illegal fix move” command, with
no clarification. Even the most basic fix move variable command is rejected
(see below, where the group does not move).

fix 123 base move variable 0.0 0.0 0.0 0.0 0.0 0.0

try this instead (untested based on the documentation):

variable zero equal 0.0
fix 123 base move variable v_zero v_zero v_zero v_zero v_zero v_zero

axel.

That appears to have worked, clearly I should've made all of the arguments
variables- thank you!