TRIANGLE_TO_FEM
Convert Mesh Data from TRIANGLE to FEM Format.

TRIANGLE_TO_FEM is a FORTRAN77 program which reads a pair of node and element files created by the TRIANGLE program and writes a corresponding pair of node and element files that correspond to the FEM format.

Usage:

triangle_to_fem prefix

• prefix.node contains the coordinates of the nodes;
• prefix.ele contains the indices of nodes forming each element.
• prefix_nodes.txt will be the FEM node file created by the program.
• prefix_elements.txt will be the FEM element file created by the program.

Licensing:

The computer code and data files described and made available on this web page are distributed under the GNU LGPL license.

Languages:

TRIANGLE_TO_FEM is available in a C version and a C++ version and a FORTRAN77 version and a FORTRAN90 version and a MATLAB version.

Related Data and Programs:

FEM_IO, a FORTRAN77 library which reads or writes node, element and data files defining a model associated with the finite element method (FEM).

FEM2D, a data directory which contains examples of 2D FEM files, a pair of files defining the coordinates of nodes, and the nodes that form triangular elements.

GMSH_TO_FEM, a FORTRAN77 program which reads a mesh data file created by the GMSH program and writes a pair of node and element files that correspond to the FEM format.

MEDIT_TO_FEM, a FORTRAN77 program which reads a mesh file created by the MEDIT program and writes a corresponding pair of node and element files that correspond to the FEM format.

SHOWME, a C program which can display the POLY files uses as input to TRIANGLE, and the output files that define meshes and other objects.

TRIANGLE, a C program which computes Voronoi diagrams and Delaunay triangulations, and creates and manipulates files that can be displayed by SHOWME.

TRIANGLE_FILES, a data directory of examples of files used by the triangle and showme programs.

TRIANGLE_IO, a FORTRAN77 library which can read or write node and element files created by the TRIANGLE program.

TRIANGLE_TO_MEDIT, a FORTRAN77 program which reads the NODE and ELE files created by triangle() to describe a triangular mesh, and writes a corresponding MESH file for input to medit().

TRIANGLE_TO_XML, a FORTRAN77 program which reads the NODE and ELE files created by triangle() to describe a triangular mesh in 2D, and writes out a corresponding XML mesh file for use by DOLFIN or FENICS.

XML_TO_FEM, a Python program which reads an XML file created by FENICS or DOLFIN, describing a mesh in 1D, 2D, or 3D, and creates corresponding FEM files, namely, a file of node coordinates, and a file of element connectivities.

Source Code:

• triangle_to_fem.f, the source code.
• triangle_to_fem.sh, BASH commands to compile the source code.

Examples and Tests:

• ell.node, a TRIANGLE node file.
• ell.ele, a TRIANGLE element file.
• ell_nodes.txt, the FEM node file created by the program.
• ell_elements.txt, the FEM element file created by the program.

List of Routines:

• MAIN is the main program for TRIANGLE_TO_FEM.
• CH_CAP capitalizes a single character.
• CH_EQI is a case insensitive comparison of two characters for equality.
• CH_TO_DIGIT returns the integer value of a base 10 digit.
• ELEMENT_DATA_READ reads the data from an element file.
• ELEMENT_SIZE_READ reads the header information from an element file.
• GET_UNIT returns a free FORTRAN unit number.
• I4MAT_WRITE writes an I4MAT file.
• NODE_DATA_READ reads the data from a node file.
• NODE_SIZE_READ reads the header information from a node file.
• R8MAT_WRITE writes an R8MAT file.
• S_TO_I4 reads an I4 from a string.
• S_TO_I4VEC reads an I4VEC from a string.
• S_TO_R8 reads an R8 from a string.
• S_TO_R8VEC reads an R8VEC from a string.
• TIMESTAMP prints the current YMDHMS date as a time stamp.

You can go up one level to the FORTRAN77 source codes.