== Beeler-Reuter Action Potential Propagation in a Ring ==

=== Description ===
 * In this example, we simulate action potential propagation in a ring. In a small section of the ring, the sodium channels are initialized to be refractory so that propagation is unidirectional.


=== Start Continuity ===
 * Launch the Continuity 6.4 Client
 * Go to '''File→Library→Search''', select '''2D_ring''' (ID: '''1226'''), right-click, and select '''Load'''.
 * A dialog box will pop-up asking if you want to save your current problem (your current problem should be blank).
 * Click to select '''Save (without reset) and proceed'''
 * Click '''OK'''

=== The shortcut: Execute pre-written script to solve EP problem ===
 * Go to File→Scripts→ScriptManager
  * Select '''EPscript'''
  * Click '''Execute Selected'''
 * Several minutes should elapse while the Electrophysiology problem executes. You can track the progress of the simulation by opening the Python Shell.
 * The solution should render and play automatically.

=== Execute steps manually ===
 * [:Continuity/Documentation/Help/MeshCalculateMesh:Mesh→Calculate Mesh...]
 * [:Continuity/Documentation/Help/MeshRenderElements:Mesh→Render Elements...]
  * Click '''lines''' radio button
  * Click '''Render''' to display mesh lines
 * [:Continuity/Documentation/Help/MeshRenderElements:Mesh→Render Elements...]
  * Click '''surfaces''' radio button
  * Click '''Render''' to display mesh surface

 * Click '''Electrophysiology→Solve→Initialize'''
  * This specifies the initial conditions for the ordinary differential equations at each point in the mesh.
 * Do a '''Send''' with '''File→Send'''
 * Click '''Electrophysiology→Solve→Integration'''
  * Set `Duration` to '''40.0''' (ms)
  * Set `Step Size` to '''0.02''' (ms)
  * Under `Output` tab, select `Display solution every` '''20''' `steps`
  * click '''OK''' to start solving
 * You may track progress of the simulation in the Python shell

 * When solution is complete, verify OpenMesh is the renderer
  *[:Continuity/Documentation/Help/ViewChangeRenderer:View→Change Renderer...]
  * Press '''OK''' when the warning pops up.
  * If '''!DejaVu''' is selected, click '''!OpenMesh''' radio button
  * Click '''OK''' to change renderer
  * You will have to re-render all objects if you were originally using '''!DejaVu'''
 * You may adjust the resolution of the rendered solution is by changing the number at [:Continuity/Documentation/Help/ViewSetDivisions:View→Set Divisions...]
 * The `Number of Divisions:` should be '''6''' by default, but you may change it to '''10'''.

 * Go to Electrophysiology→Render→Render Solution
  * Set `Min value` to '''-80'''
  * Set `Max value:` to '''0''' or '''10'''
  * Click '''OK''' to view an animated color map of voltage