Introduce an arbitrarily shaped dislocation polygon (loop) into the crystal.

<p>
Usage: <tt>input = [ <i>enable  store nu  a bx by bz  n x_1 y_1 z_1 x_2 y_2 z_2 &hellip; x_n y_n z_n</i> ] 
       makedislellipse </tt>

<p>
<tt><i>enable = 1</i></tt> activates this command.  
<br>
If <tt><i>store</i> = 1</tt>, the displacement field is not committed to the atoms
positions, but is stored/accumulated in array <tt>storedr</tt>, until this command is
(or other commands such as <tt>makedipole</tt>) is called again with option 
<tt><i>store</i> = 0</tt>.
<br>
<tt><i>nu</i></tt> is the Poisson's ratio of the crystal.
<br>
<tt><i>a</i></tt> is a length scale (in &Aring;) for the Burgers vector.
<br>
<tt><i>bx, by, bz</i></tt> is the Burgers vector (in real coordinates) in unit of 
  <tt><i>a</i></tt>.
<br>
<tt><i>n</i></tt> is the number of nodes of the polygon.
<br>
<tt><i>x1, y1, z1, x_2 y_2 z_2 &hellip; x_n y_n z_n</i></tt> are the polygon nodes in 
 real coordinates (in &Aring;).


<p>
Note: all cut planes go through the first node <tt><i>x_1 y_1 z_1</i></tt>.

<p>
References: D. M. Barnett, <i>The displacement field of a triangular dislocation loop</i>,
  Phil. Mag. A. (1985) vol.51 383--387;
  D. M. Barnett and R. W. Balluffi, <i>The displacement field of a triangular
  dislocation loop -- a correction with commentary</i>, Phil. Mag. Lett. (2007) vol.87 943--944;
  A. Van Oosterom and J. Strackee, <i>The Solid angle of a plane trangle</i>,
  IEEE transactions on biomedical engr. (1983) vol.bme-30 125--126.

<p>
For more information, ask Keonwook Kang.

<p>
Also see <tt>makedislellipse</tt>.

