Introduce an elliptical shaped dislocation loop into the crystal.

<p>
Usage: <tt>input = [ <i>enable  Ra Rb a bx by bz lx ly lz nx ny nz x0 y0 z0 store</i> ] 
       makedislellipse </tt>

<p>
<tt><i>enable = 1</i></tt> activates this command.  <br>
<tt><i>Ra, Rb</i></tt> defines the major and minor axes of the ellipse (in &Aring;). <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>lx, ly, lz</i></tt> is the line orientation (in real coordinates)
  of the major axis of the ellipse.<br>
<tt><i>nx, ny, nz</i></tt> is the plane normal vector (in real coordinates)
  of the ellipse.<br>
<tt><i>x0, y0, z0</i></tt> is the center point (in real coordinates) of the ellipse.<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>storedr</i> = 0</tt>.

<p>
Note: the displacement field used in this function is only an approximation.  It is simply
proportional to the solid angle of the ellipse viewed from the field point.  The actual
displacement field must contain a term that depends on the Poisson's ratio.

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