==========================================
**Boundary conditions  (Randbedingungen)**
==========================================

.. role:: red
	  
.. admonition:: Command: def_bcond_vpo(x1, y1, x2, y2)

 Tangential boundary condition
 
 **Parameter**
  | :red:`x1,y1` Start-point coordinates
  | :red:`x2,y2` End-point coordinates 
 

.. admonition:: Command: def_bcond_vpc(x1, y1, x2, y2, vpr, vpi)

 Constant vector potential
 
 **Parameter**
  | :red:`x1,y1` Start-point coordinates
  | :red:`x2,y2` End-point coordinates
  | :red:`vpr` Real part of vector potential [Vs/m] 
  | :red:`vpi` Imaginary part of vector potential [Vs/m] 

.. admonition:: Command: def_bcond(x1, y1, x2, y2, x3, y3, x4, y4, type)

 Periodic boundary condition

 **Parameter**
  | :red:`x/y1` Coordinates of point 1 (left, above)
  | :red:`x/y2` Coordinates of point 2 (left, below)
  | :red:`x/y3` Coordinates of point 3 (right, below)
  | :red:`x/y4` Coordinates of point 4 (right, above)
  | :red:`type` Type of boundary condition. Positive periodicity: *4* (deprecated) or *"pos"*, negative periodicity: *3* (deprecated) oder *"neg"*.

 Example:
 ::
    
  def_bcond(x1,y1,x2,y2,x3,y3,x4,y4,"neg")   -- apply a negativ periodic boundary condition
  def_bcond(x1,y1,x2,y2,x3,y3,x4,y4,3)       -- deprecated version
 
.. admonition:: Command: def_bcond_inf() 

 Infinity boundary condition

.. admonition:: Command: def_bcond_int_vpo(x1, y1, x2, y2, x3, y3, ..)

 Internal condition (vector potential zero) within the defined area
  
 **Parameter**
  :red:`xi, yi` Point of the area surounding polygon
 
.. admonition:: Command: def_bcond_int_vpc(vpr, vpi, x1, y1, x2, y2, x3, y3, ..)

 Internal condition (vector potential constant) within the defined area

 **Parameter**
  | :red:`vpr` Real part of vector potential [Vs/m] 
  | :red:`vpi` Imaginary part of vector potential [Vs/m] 
  | :red:`xi, yi` Point of the area surounding polygon
 
.. admonition:: Command: def_nccond_vpo(x1, y1, x2, y2)

 Definition of the condition of any node chain, vector potential = 0
 
 **Parameter**
  | :red:`x1,y1` Start-point coordinates [unit]
  | :red:`x2,y2` End-point coordinates [unit]

.. admonition:: Command: def_nccond_vpc(x1, y1, x2, y2, vpr, vpi)

  Definition of the condition of any node chain, vector potential = constant

 **Parameter**
  | :red:`x1,y1` Start-point coordinates [unit]
  | :red:`x2,y2` End-point coordinates [unit]
  | :red:`vpr` Real part of vector potential [Vs/m] 
  | :red:`vpi` Imaginary part of vector potential [Vs/m] 

.. admonition:: Command: del_bcond()

 Delete all boundary conditions