error " Fix in variable not computed at compatible time (../variable.cpp:3034)"

hello dear
i’m trying to simulate water and cu.i want to compute viscosity. when i run it shows this error " Fix in variable not computed at compatible time (…/variable.cpp:3034)"
i’ve checked it: (Fixes generate their values on specific timesteps. The variable is requesting the values on a
non-allowed timestep)
does anybody know what should i do?
thanks
regard

input code

min_modify dmax 0.01
minimize 1.0e-8 0 10000 30000

dump 1 all custom 10000 dump.equilibrium. id type x y z vx vy vz

---------- output----------------------------------------------

thermo 100
thermo_style custom step etotal enthalpy pe press ke
thermo_modify flush yes

velocity all create 300.0 4928459 rot yes dist gaussian #23482341

fix 1 hydrogen shake 1e-6 500 0 m 1.0 a 1 #for hydrogen
fix 12 water npt temp 300.0 300.0 100.0 iso 0.0 0.0 1000.0

compute 1 all temp
compute peatom all pe/atom
compute keatom all ke/atom

hello dear
i'm trying to simulate water and cu.i want to compute viscosity. when i run
it shows this error " Fix in variable not computed at compatible time
(../variable.cpp:3034)"
i've checked it: (Fixes generate their values on specific timesteps. The
variable is requesting the values on a
non-allowed timestep)
does anybody know what should i do?

isn't it obvious?
either change the fix settings, so that it computes its property at
the same frequency as when you access it through the variable or
change the frequency of when you access the variable so that it
matches the frequency that the fix provides its data.

axel.

Hi!

Fix SS is calculated every 2000 timesteps in your simulation, you want to see
thermodynamic output which uses this fix (via vxx and vxy) every 100 timesteps.
Obviously, this can’t be done.

You can either calculate stress ACF on shorter timescale, or adjust thermo frequency

to match the stress ACF accumulation interval.

Regards,

Vasily