Electrical Methods Mesh Files

E4D creates the a series of files descibing the mesh. These files all begin with the same prefix as the mesh configuration file (<e4d_mesh.cfg>), where e4d_mesh is the user chosen mesh file name. Although it is not necessary to understand the format of the mesh files for standard applications in E4D, the table below provides a description of the mesh file formats to facilitate more advanced uses of E4D.

File Name	Produced by	Description
<e4d_mesh.1.node>	tetgen	Provides locations of nodes and boundary markers for each node in the mesh (see tetgen documentation).
<e4d_mesh.1.ele>	tetgen	Describes how nodes are connected to form elements and assigns each element a zone number (see tetgen documentation).
<e4d_mesh.1.neigh>	tetgen	Provides a list of neighboring elements for each element in the mesh (see tetgen documentation).
<e4d_mesh.1.face>	tetgen	Provides a list of faces that constitute boundaries defined in the mesh configuration file (see tetgen documentation).
<e4d_mesh.trn>	E4D	Provides the horizontal (x and y) and vertical (z) coordinate translations used internally by E4D to optimize numerical precision.
<e4d_mesh.sig>	E4D	Provides a distribution of real conductivities and phase angles (if generating for SIP) on the mesh. Values are specified in the <e4d_mesh.cfg>file Zone Configuation Block.

For reference, E4D calls tetgen with the following command line options:

tetgen -pnq<m_qual>a<max_evol>aAA <e4d_mesh.poly>

where m_qual and max_evol are specified in the mesh configuration file, and <e4d_mesh.poly> is the tetgen input file created by E4D using options specified in the mesh configuration file.