access to Indent force

LAMMPS LAMMPS Mailing List Mirror
1

Hello,

I’d like to access the force on indenter, but don’t know how to. The manual says “This fix computes a global scalar energy and a global 3-vector of forces (on the indenter), which can be accessed by various output commands.” but doesn’t tell how to access the force exactly (even in the ‘output commands’). Some examples found in the mail list use f_ID[2], where ID is for indent fix. So my question is:

Is f_ID[1] for the energy, and f_ID[2] is the force vector such that f_ID[2][1] for force_x, f_ID[2][2] for force_y,and f_ID[2][3] for force_z?

Thanks.
Chunguang

Section_howto.html (105 KB)

2

Hello,

I'd like to access the force on indenter, but don't know how to. The manual
says "This fix computes a global scalar energy and a global 3-vector of
forces (on the indenter), which can be accessed by various output commands."
but doesn't tell how to access the force exactly (even in the 'output
commands'). Some examples found in the mail list use f_ID[2], where ID is
for indent fix. So my question is:

Is f_ID[1] for the energy, and f_ID[2] is the force vector such that
f_ID[2][1] for force_x, f_ID[2][2] for force_y,and f_ID[2][3] for force_z?

no.

f_ID indicates accessing a global *scalar*
f_ID[1] indicates accessing element 1 of a global *vector*
f_ID[1][1] indicates accessing element (1,1) of a global *array*

axel.

3

Thanks, Axel. So I guess:
energy is f_ID
force on indenter along x,y,z is f_ID[1], f_ID[2], f_ID[3].

4

You don’t have to guess. The fix indent doc page

says exactly that.

This fix computes a global scalar energy and a global 3-vector of
forces (on the indenter),

Steve