[lammps-users] About output indent force

Hi, all users and steve,

I want to know how to output the indent force in the examples.

My script is as following:

fix 4 all indent 1000.0 sphere 10 13 0 5.0 vel 0.0 -0.02 0.0

fix 6 all ave/time 1 100 1000 f_indent f_indent[1] file temp.indent

THe error message I got is " ERROR: Illegal fix ave/time command ?

Dose anybody know where I am wrong? Typically, I am not quite understand what is the command “fix ave/time f_indent” meaning.
I copy it from user manual.

Thanks for your help.

AJing Cao

Hi, Cao

On the doc page of the “fix ave/time”, it says that
the value which is considered to be averaged can
be c_ID, c_ID[N], f_ID, f_ID[N], v_name.

Thus in your case, the fix should look like:

fix 4 all indent 1000.0 sphere 10 13 0 5.0 vel 0.0 -0.02 0.0
fix 6 all ave/time 1 100 1000 f_4 f_4[1] file temp.indent

The usage of “fix ave/time” can be found on the doc page.
See http://lammps.sandia.gov/doc/fix_ave_time.html.

L. Wan
2008/5/28

2008/5/28, AJING CAO <[email protected]…8…>:

Dear, Liang,

Thanks for your reply.

However, it doesn’t work.

I am not sure if in "fix 6 all ave/time 1 100 1000 f_indent f_4[1] file temp.indent ", f_indent is a f_ID or a tag especially for indent case. Why two f_indent appears in the example? what it represents?

Ajing

Dear, Liang,

Thanks for your reply.

However, it doesn’t work.

I am not sure if in "fix 6 all ave/time 1 100 1000 f_indent f_4[1] file temp.indent ", f_indent is a f_ID or a tag especially for indent case. Why two f_indent appears in the example? what it represents?

Ajing

Hi Cao,

In "fix 6 all ave/time 1 100 1000 f_indent f_4[1] file temp.indent ",
f_indent should correspond to the scalar quantity calcuated by
a fix with the ID named “indent”. See the doc page of the “fix indent”
(http://lammps.sandia.gov/doc/fix_indent.html).

However, in your case, if you’d like to output the indent force calucated by

fix 4 all indent 1000.0 sphere 10 13 0 5.0 vel 0.0 -0.02 0.0

you should specify the corresonding argument of the “fix ave/time”
as “f_4[1]”, “f_4[2]”, “f_4[3]”.

The reason that you got the error message " ERROR: Illegal fix ave/time command "
is probably because that there is no fix which is called “indent”. And
you should distinguish between the style name of the fix (“indent”) and
the ID of the fix (“4”).

L. Wan
2008/5/28

2008/5/28, AJING CAO <[email protected]…8…>: