Hello Everyone,
Firstly, I use the latest stable version of LAMMPS (29 Aug 2024) on Ubuntu 24.04.2.
I want to calculate the stress autocorrelation function and use fix ave/correlate/long:
fix g all ave/correlate/long 1 5000 v_pxx v_pyy v_pzz v_pxy v_pxz v_pyz v_nxy v_nxz v_nyz type auto nlen 16 ncount 2 ncorr 30 file G${a}.txt
This is the output:
# Timestep: 0
0 455.129 452.42 455.602 0.00470603 7.74652e-05 0.00511631 0.00404431 0.000122775 0.0055764
# Timestep: 5000
0 459.581 459.5 459.473 0.00432385 0.00418313 0.00394885 0.0175516 0.0172921 0.0167453
0.02 459.577 459.496 459.469 0.00264374 0.00247464 0.00235646 0.0109809 0.0106915 0.0102103
...
the first column is the time lag, and the #timestep is when the calculation if performed. So we have different blocks for each timestep.
My question is the following:
Is it is the final block we are interested in, or we need to average out between different blocks? I think it is the final block?
Thank you,
Alex
PS. I have read the documentation, but did not find a response. Maybe the way the multiple-tau algorithm works would help figuring this out.