LAMMPS WWW Site - LAMMPS Documentation - LAMMPS Mailing List Archives
[lammps-users] questions about fix ave/chunk density/number
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

[lammps-users] questions about fix ave/chunk density/number

From: ruiyan <r-yan14@...61...>
Date: Thu, 20 Jul 2017 04:06:50 +0800 (GMT+08:00)

Dear all, 

I used fix ave/chunk command to calculate the density number of system consisting of solid and liquid Al. The commands I used are as follow:

compute      density_num_1   all   chunk/atom   bin/1d   z   lower   0.1

fix         1   all   ave/chunk   500  100   50000   density_num_1   density/number   file   density_number_bin_0.1.txt 

After checking the result file, I have two questions: 

(1) The result file has four columns: chundID, chunk_coordiante, Ncount, density/number. Since Ncount is the number of atoms in a bin, it should be an integer, but none of Ncounts is integer. All of them are floats. 

(2) Since the value of delta in compute chunk/atom is much smaller than interplane spacing of Al crystal(about 4.05), Ncounts of some bins in solid Al should be zero. But I can't find a bin whose Ncount is zero. 

Why these happen? Is there anything wrong in my simulation?