jburkardt

FEM_TO_TRIANGLE\ Convert a Mesh from FEM to Triangle Format {#fem_to_triangle-convert-a-mesh-from-fem-to-triangle-format align=”center”} ==========================================

FEM_TO_TRIANGLE is a C program which reads FEM files of node coordinates and element connectivity, which define a mesh of a 2D region, divided into triangular elements, and creates a corresponding pair of Triangle files.

These files can be used as input to Triangle for viewing, or mesh refinement.

Usage: {#usage align=”center”}

fem_to_triangle prefix

where prefix is the common filename prefix:

‘prefix’_nodes.txt contains the node coordinates,
‘prefix’_elements.txt contains the element definitions.
‘prefix’.node will be the Triangle node file.
‘prefix’.ele will be the Triangle element file.

Licensing: {#licensing align=”center”}

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

Languages: {#languages align=”center”}

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

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

FEM_TO_GMSH, a C program which reads FEM files definining a 1D, 2D or 3D mesh, namely a file of node coordinates and a file of elements defined by node indices, and creates a Gmsh mesh file.

FEM_TO_MEDIT, a C program which reads a pair of FEM files defining node coordinates and elements, and creates a corresponding MEDIT mesh file.

FEM_TO_XML, a C program which reads FEM files defining a 1D, 2D or 3D mesh, namely a file of node coordinates and a file of elements defined by node indices, and creates a corresponding XML file for input to DOLFIN or FENICS.

FEM2D, a data directory which contains examples of 2D FEM files, text files that describe a 2D geometry and node values associated with the finite element method (FEM);

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

TRIANGLE_IO, a C library which can read or write some of the files created by Jonathan Shewchuk’s triangle() program.

Source Code: {#source-code align=”center”}

fem_to_triangle.c, the source code.

Examples and Tests: {#examples-and-tests align=”center”}

ELL is an L-shaped region with 65 nodes and 96 elements.

ell_nodes.txt, the node coordinates in FEM format.
ell_elements.txt, the elements in FEM format.
ell.node, the node coordinates in TRIANGLE format.
ell.ele, the elements in TRIANGLE format.

List of Routines: {#list-of-routines align=”center”}

MAIN is the main program for FEM_TO_TRIANGLE.
CH_CAP capitalizes a single character.
CH_EQI is a case insensitive comparison of two characters for equality.
CH_TO_DIGIT returns the value of a base 10 digit.
FILE_COLUMN_COUNT counts the number of columns in the first line of a file.
FILE_ROW_COUNT counts the number of row records in a file.
GET_UNIT returns a free FORTRAN unit number.
I4MAT_DATA_READ reads data from an I4MAT file.
I4MAT_HEADER_READ reads the header from an I4MAT.
I4MAT_TRANSPOSE_PRINT prints an I4MAT, transposed.
I4MAT_TRANSPOSE_PRINT_SOME prints some of the transpose of an I4MAT.
MESH_BASE_ZERO ensures that the element definition is zero-based.
R8MAT_DATA_READ reads data from an R8MAT file.
R8MAT_HEADER_READ reads the header from an R8MAT file.
R8MAT_TRANSPOSE_PRINT prints an R8MAT, transposed.
R8MAT_TRANSPOSE_PRINT_SOME prints some of an R8MAT, transposed.
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.
S_WORD_COUNT counts the number of “words” in a string.
TIMESTAMP prints the current YMDHMS date as a time stamp.
TRIANGLE_ELEMENT_WRITE writes a TRIANGLE “.ele” file.
TRIANGLE_NODE_WRITE writes a TRIANGLE “.node” file.

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

Last revised on 14 October 2014.