{c}
{wiki}

Specifies fixed values.

Can be used for <elliptic partial differential equations> and <parabolic partial differential equations>.

Numerical examples:
* with <FreeFem>:
  * <heat-dirichlet.1d.freefem>
  * <heat-dirichlet-2d-freefem>


Dirichlet boundary condition

{c}
{wiki}

Specifies the derivative in a direction normal to the boundary.

Can be used for <elliptic partial differential equations> and <parabolic partial differential equations>.


Neumann boundary condition

http://www.cns.gatech.edu/~predrag/courses/PHYS-6124-12/StGoChap6.pdf 6.1 "Classification of PDE's" clarifies which boundary conditions are needed for existence and uniqueness of each <classification of second order partial differential equations into elliptic, parabolic and hyperbolic>[type of second order of PDE]:
* <elliptic partial differential equation> and <parabolic partial differential equation>: <Dirichlet boundary condition> or <Neumann boundary condition>
* <hyperbolic partial differential equation>: <Cauchy boundary condition>


Ciro Santilli @cirosantilli 37

 Incoming links: Parabolic partial differential equation