This is the output from executing "tetgen -h" on command line.

Parameter	Description
-p	Tetrahedralizes a piecewise linear complex (PLC).
-Y	Preserves the input surface mesh (does not modify it).
-r	Reconstructs a previously generated mesh.
-q	Refines mesh (to improve mesh quality).
-R	Mesh coarsening (to reduce the mesh elements).
-A	Assigns attributes to tetrahedra in different regions.
-a	Applies a maximum tetrahedron volume constraint.
-m	Applies a mesh sizing function.
-i	Inserts a list of additional points.
-O	Specifies the level of mesh optimization.
-S	Specifies maximum number of added points.
-T	Sets a tolerance for coplanar test (default 1e-8).
-X	Suppresses use of exact arithmetic.
-M	No merge of coplanar facets or very close vertices.
-w	Generates weighted Delaunay (regular) triangulation.
-c	Retains the convex hull of the PLC.
-d	Detects self-intersections of facets of the PLC.
-z	Numbers all output items starting from zero.
-f	Outputs all faces to .face file.
-e	Outputs all edges to .edge file.
-n	Outputs tetrahedra neighbors to .neigh file.
-v	Outputs Voronoi diagram to files.
-g	Outputs mesh to .mesh file for viewing by Medit.
-k	Outputs mesh to .vtk file for viewing by Paraview.
-J	No jettison of unused vertices from output .node file.
-B	Suppresses output of boundary information.
-N	Suppresses output of .node file.
-E	Suppresses output of .ele file.
-F	Suppresses output of .face and .edge file.
-I	Suppresses mesh iteration numbers.
-C	Checks the consistency of the final mesh.
-Q	Quiet: No terminal output except errors.
-V	Verbose: Detailed information, more terminal output.
-h	Help: A brief instruction for using TetGen.

Examples of TetGen input strings:

Input String	Description
-pq1.414a.1	generates a mesh whose tetrahedra have radius-edge ratio smaller than 1.414 and have volume of 0.1 or less