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EField Embedding

EField displays the electric potential from point charges.  An external potential energy function can also be specified. The electric field is approximated by taking the gradient of the potential.

EField is embedded using the following html tag:

<applet
  code="eField4.EField.class"
  archive="EField4_.jar,STools4.jar"
  codebase="../classes"
  align="middle"
  width="400"
  height="450"
  >

<param name="FPS" value="10" />
<param name="dt" value="0.02" />
<param name="PointChargeMode" value="true" />
<param name="ShowControls" value="true" />
<param name="ShowContours" value="true" />
<param name="ShowFieldLines" value="false" />
<param name="ShowFieldVectors" value="true" />
<param name="ShowLabels" value="false" />
<param name="ShowCharge" value="true" />
<param name="Potential" value="x*y" />
<param name="Range" value="-5,5,-5,5" />
<param name="GridSize" value="64" />
</applet>

EField Parameters
FPS  int  Animation frames per second.
Dt  double  Animation time step between frames.
ShowControls  boolean  True to show simple user interface.
ShowContours  boolean  Show equipotential contours.
ShowPoles  boolean  Show fixed point charges as circles.
ShowLables  boolean  Adds labels to contour lines.
ShowFieldLines  boolean  Draws field lines.  Use field vectors if feld line algorithm not give good results.
ShowFieldVectors  boolean  Draws field vectors.
PointChargeMode  boolean  Selects between point (1/(r^2) and line (1/r) functions for potential energy from a point charge.
Potentail  string  External potential energy function.
Range  string  Min and max values for the scale.
GridSize  int  The size of the n by n grid.

STools Parameters
AppletNames  string  A comma delimited list of applet names occurring within this html page. (See OnLoad.)
Debug  int  Enables debugging messages in Java console; 0 = no messages, 255 = verbose messages.
OnLoad  string  A JavaScript function that will be invoked using LiveConnect after all applets have been loaded.  (See AppletNames.)
Resources  string  A file containing translations of internal text such as buttons and labels.