1.. index:: compute smd/ulsph/stress
2
3compute smd/ulsph/stress command
4================================
5
6Syntax
7""""""
8
9.. code-block:: LAMMPS
10
11   compute ID group-ID smd/ulsph/stress
12
13* ID, group-ID are documented in :doc:`compute <compute>` command
14* smd/ulsph/stress = style name of this compute command
15
16Examples
17""""""""
18
19.. code-block:: LAMMPS
20
21   compute 1 all smd/ulsph/stress
22
23Description
24"""""""""""
25
26Define a computation that outputs the Cauchy stress tensor.
27
28See `this PDF guide <PDF/SMD_LAMMPS_userguide.pdf>`_ to using Smooth
29Mach Dynamics in LAMMPS.
30
31Output info
32"""""""""""
33
34This compute calculates a per-particle vector of vectors (tensors),
35which can be accessed by any command that uses per-particle values
36from a compute as input. See the :doc:`Howto output <Howto_output>` doc
37page for an overview of LAMMPS output options.
38
39The values will be given in :doc:`units <units>` of pressure.
40
41The per-particle vector has 7 entries. The first six entries
42correspond to the xx, yy, zz, xy, xz, yz components of the symmetric
43Cauchy stress tensor. The seventh entry is the second invariant of the
44stress tensor, i.e., the von Mises equivalent stress.
45
46Restrictions
47""""""""""""
48
49This compute is part of the MACHDYN package.  It is only enabled if
50LAMMPS was built with that package. See the :doc:`Build package <Build_package>` page for more info. This compute can
51only be used for particles which interact with the updated Lagrangian
52SPH pair style.
53
54Related commands
55""""""""""""""""
56
57:doc:`compute smd/ulsph/strain <compute_smd_ulsph_strain>`, :doc:`compute smd/ulsph/strain/rate <compute_smd_ulsph_strain_rate>` :doc:`compute smd/tlsph/stress <compute_smd_tlsph_stress>`
58
59Default
60"""""""
61
62none
63