Update pair_body_rounded_polyhedron docs

doc/src/pair_body_rounded_polygon.rst

@@ -115,7 +115,7 @@ or in the data file read by the :doc:`read_data <read_data>` command:
 * :math:`k_n` (energy/distance\^2 units)
 * :math:`k_{na}` (energy/distance\^2 units)
 
-Effectively, :math:`k_n` and :math:`k_na` are the slopes of the red lines in the plot
+Effectively, :math:`k_n` and :math:`k_{na}` are the slopes of the red lines in the plot
 above for force versus surface separation, for :math:`\delta_n < 0` and
 :math:`0 < \delta_n < r_c` respectively.
 

doc/src/pair_body_rounded_polyhedron.rst

@@ -1,16 +1,18 @@
-.. index:: pair\_style body/rounded/polyhedron
+.. index:: pair_style body/rounded/polyhedron
 
-pair\_style body/rounded/polyhedron command
-===========================================
+pair_style body/rounded/polyhedron command
+==========================================
 
 Syntax
 """"""
 
 
-.. parsed-literal::
+.. code-block:: LAMMPS
 
    pair_style body/rounded/polyhedron c_n c_t mu delta_ua cutoff
 
+.. parsed-literal::
+
    c_n = normal damping coefficient
    c_t = tangential damping coefficient
    mu = normal friction coefficient during gross sliding
@@ -21,10 +23,10 @@ Examples
 """"""""
 
 
-.. parsed-literal::
+.. code-block:: LAMMPS
 
    pair_style body/rounded/polyhedron 20.0 5.0 0.0 1.0 0.5
-   pair_coeff \* \* 100.0 1.0
+   pair_coeff * * 100.0 1.0
    pair_coeff 1 1 100.0 1.0
 
 Description
@@ -33,7 +35,8 @@ Description
 Style *body/rounded/polygon* is for use with 3d models of body
 particles of style *rounded/polyhedron*\ .  It calculates pairwise
 body/body interactions which can include body particles modeled as
-1-vertex spheres with a specified diameter.  See the :doc:`Howto body <Howto_body>` doc page for more details on using body
+1-vertex spheres with a specified diameter.  See the
+:doc:`Howto body <Howto_body>` doc page for more details on using body
 rounded/polyhedron particles.
 
 This pairwise interaction between the rounded polyhedra is described
@@ -54,26 +57,35 @@ separation of their respective rounded surfaces, not by the separation
 of the vertices, edges, and faces themselves.
 
 This means that the specified cutoff in the pair\_style command is the
-cutoff distance, r\_c, for the surface separation, \delta\_n (see figure
+cutoff distance, :math:`r_c`, for the surface separation, :math:`\delta_n` (see figure
 below).  This is the distance at which two particles no longer
-interact.  If r\_c is specified as 0.0, then it is a contact-only
+interact.  If :math:`r_c` is specified as 0.0, then it is a contact-only
 interaction.  I.e. the two particles must overlap in order to exert a
-repulsive force on each other.  If r\_c > 0.0, then the force between
+repulsive force on each other.  If :math:`r_c > 0.0`, then the force between
 two particles will be attractive for surface separations from 0 to
-r\_c, and repulsive once the particles overlap.
+:math:`r_c`, and repulsive once the particles overlap.
 
 Note that unlike for other pair styles, the specified cutoff is not
 the distance between the centers of two particles at which they stop
 interacting.  This center-to-center distance depends on the shape and
 size of the two particles and their relative orientation.  LAMMPS
 takes that into account when computing the surface separation distance
-and applying the r\_c cutoff.
+and applying the :math:`r_c` cutoff.
 
 The forces between vertex-vertex, vertex-edge, vertex-face, edge-edge,
 and edge-face overlaps are given by:
 
-.. image:: Eqs/pair_body_rounded.jpg
-   :align: center
+.. math::
+
+ F_n &= \begin{cases}
+        k_n \delta_n - c_n v_n,    & \delta_n \le 0 \\
+       -k_{na} \delta_n - c_n v_n  & 0 < \delta_n \le r_c \\
+        0                          & \delta_n > r_c \\
+        \end{cases} \\
+ F_t &= \begin{cases}
+        \mu k_n \delta_n - c_t v_t & \delta_n \le 0 \\
+        0                          & \delta_n > 0
+        \end{cases}
 
 .. image:: JPG/pair_body_rounded.jpg
    :align: center
@@ -93,20 +105,21 @@ The following coefficients must be defined for each pair of atom types
 via the :doc:`pair_coeff <pair_coeff>` command as in the examples above,
 or in the data file read by the :doc:`read_data <read_data>` command:
 
-* k\_n (energy/distance\^2 units)
-* k\_na (energy/distance\^2 units)
+* :math:`k_n` (energy/distance\^2 units)
+* :math:`k_{na}` (energy/distance\^2 units)
 
-Effectively, k\_n and k\_na are the slopes of the red lines in the plot
-above for force versus surface separation, for \delta\_n < 0 and 0 <
-\delta\_n < r\_c respectively.
+Effectively, :math:`k_n` and :math:`k_{na}` are the slopes of the red lines in the plot
+above for force versus surface separation, for :math:`\delta_n` < 0 and
+:math:`0 < \delta_n < r_c` respectively.
 
 **Mixing, shift, table, tail correction, restart, rRESPA info**\ :
 
 This pair style does not support the :doc:`pair_modify <pair_modify>`
 mix, shift, table, and tail options.
 
-This pair style does not write its information to :doc:`binary restart files <restart>`.  Thus, you need to re-specify the pair\_style and
-pair\_coeff commands in an input script that reads a restart file.
+This pair style does not write its information to :doc:`binary restart files <restart>`.
+Thus, you need to re-specify the pair\_style and pair\_coeff
+commands in an input script that reads a restart file.
 
 This pair style can only be used via the *pair* keyword of the
 :doc:`run_style respa <run_style>` command.  It does not support the