printing time-avg rdf

Hi all

I have been printing rdfs with this command:

compute 2 all rdf 1000 7 7
fix 2 all ave/time 100 40000 4000000 c_2 file file.rdf mode vector

However, above works only when starting timestep if 4000000 and ending timestep is 8000000.

It does not work ( does not print final time-average rdf) when starting timestep is 2000000 and ending timestep is 6000000. Seems like it requires ending timestep to be multiple of 4000000 which is not what 4000000 in the command indicates.

Can anyone resolve this?


Dear Chetan,

I've encountered a similar problem once. After a _very_ careful reading
of manual I found: "The final averaged quantities are generated on
timesteps that are a mlutiple of Nfreq".
You may use reset_timestep command to shift starting timestep.

Best regards,

So far as I can recall, every command in LAMMPS that has an argument
to do something every N steps, interprets that to mean steps that
are multiples of N. Dumps, thermo output, fix ave output, etc.

If you ask fix ave/time to do output every 400K steps and
start on step 200K, then it can't do output on step 400K (no
data for steps 0-200K), nor will it do output at some arbitrary
ending step, unless it is a multiple of 400K.


Thanks, Steve and Vasily.