Some important properties of edge shape functions

Some important properties of edge shape functions are investigated such as (1) a method for deriving edge shape functions from nodal shape functions, and (2) required conditions for solving the uniform magnetic field problem using hexahedral edge elements. The followings are obtained for the respective items: (1) there are a few possibilities for deriving edge shape functions from identical nodal shape functions, and (2) 1st order hexahedral edge elements cannot give uniform fields.