jburkardt

TRIANGULATION_SVG\ SVG Image of Triangulation {#triangulation_svg-svg-image-of-triangulation align=”center”} ==========================

TRIANGULATION_SVG is a C++ program which creates an SVG image of a triangulation, which can be displayed by an web browser.

TRIANGULATION_SVG reads one file listing the nodes, and a second file consisting of groups of 3, 4 or 6 nodes that make up elements.

Usage: {#usage align=”center”}

triangulation_svg prefix

where ‘prefix’ is the common prefix for the node and element files, and will also be used to name the output file:

‘prefix’_nodes.txt, the node coordinates.
‘prefix’_elements.txt, the triangulation
‘prefix’.svg, the plot file

Licensing: {#licensing align=”center”}

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

Languages: {#languages align=”center”}

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

TRIANGLE_SVG, a C++ library which uses Scalable Vector Graphics (SVG) to plot a triangle and any number of points, to illustrate quadrature rules and sampling techniques.

TRIANGULATION, a C++ library which carries out various operations on order 3 (“linear”) or order 6 (“quadratic”) triangulations.

TRIANGULATION_NODE_TO_ELEMENT, a C++ program which reads files describing a set of nodes, their triangulation, and the value of one or more quantities at each node, and outputs a file that averages the quantities for each element. This operation in effect creates an “order1” finite element model of the data.

TRIANGULATION_PLOT, a C++ program which plots the nodes and elements of a triangulation as a PostScript (PS) file;

Reference: {#reference align=”center”}

W3C, Scalable Vector Graphics 1.1 (Second Edition), 16 August 2011, http://www.w3.org/TR/SVG11/

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

triangulation_svg.cpp, the source code.

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

LAKE is a lake region.

lake_nodes.txt the point coordinates.
lake_elements.txt the triangulation.
lake.svg an SVG image of the triangulation.

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

MAIN is the main program for TRIANGULATION_SVG.
CH_CAP capitalizes a single character.
CH_EQI is true if two characters are equal, disregarding case.
CH_TO_DIGIT returns the integer value of a base 10 digit.
FILE_COLUMN_COUNT counts the columns in the first line of a file.
FILE_ROW_COUNT counts the number of row records in a file.
I4_MAX returns the maximum of two integers.
I4_MIN returns the smaller of two integers.
I4_MODP returns the nonnegative remainder of integer division.
I4_WRAP forces an integer to lie between given limits by wrapping.
I4MAT_DATA_READ reads data from an I4MAT file.
I4MAT_HEADER_READ reads the header from an I4MAT file.
I4MAT_TRANSPOSE_PRINT_SOME prints some of an I4MAT, transposed.
MESH_BASE_ZERO ensures that the element definition is zero-based.
R8_HUGE returns a “huge” R8.
R8_MAX returns the maximum of two R8’s.
R8_MIN returns the minimum of two R8’s.
R8_NINT returns the nearest integer to an R8.
R8MAT_DATA_READ reads the data from an R8MAT file.
R8MAT_HEADER_READ reads the header from an R8MAT file.
R8MAT_TRANSPOSE_PRINT_SOME prints some of an R8MAT, transposed.
S_BLANK_DELETE removes blanks and left justifies the remainder.
S_LEN_TRIM returns the length of a string to the last nonblank.
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.
TRIANGULATION_PLOT plots a triangulation in SVG format.

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

Last revised on 07 April 2014.