which one is better, vacf or ave/correlate of velocity

Respected authority,
Please clarify my doubt regarding which way is better to find velocity auto correlation, using vacf or ave/correlate?

Let say I have only 1 atom in my group.

For given ‘delta’ (time) vacf calculates only once the value of coefficient but ave/correlate calculates the same value by carrying out average over several samples having same delta gap.

This gives me the feeling that ave/correlate is better than vacf.

Please rectify me , if I am wrong at any point.

Yes, that is correct. fix ave/correlate is a newer, more general method in LAMMPS that allows an arbitrary number of prior reference values to be compared to the current value. compute vacf only uses the initial value as reference.

Thank you for the reply.