Properties of a Triangle

TRIANGLE_PROPERTIES, a C++ code which can compute properties of a triangle, including angles, area, centroid, circumcircle, edge lengths, incircle, orientation, orthocenter, and quality.

These properties include:


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


TRIANGLE_PROPERTIES is available in a C version and a C++ version and a FORTRAN90 version and a MATLAB version and a Python version.

Related Data and Programs:

GEOMETRY, a C++ library which performs geometric calculations in 2, 3 and N dimensional space.

HYPERSPHERE_PROPERTIES, a C++ library which carries out various operations for an M-dimensional hypersphere, including converting between Cartesian and spherical coordinates, stereographic projection, sampling the surface of the sphere, and computing the surface area and volume.

POLYGON_PROPERTIES, a C++ library which computes properties of an arbitrary polygon in the plane, defined by a sequence of vertices, including interior angles, area, centroid, containment of a point, convexity, diameter, distance to a point, inradius, lattice area, nearest point in set, outradius, uniform sampling.

TETRAHEDRON_PROPERTIES, a C++ program which computes properties of a given tetrahedron.

TRIANGLE_ANALYZE, a C++ program which reads a triangle from a file, and then reports various properties.

TRIANGLE_INTERPOLATE, a C++ library which shows how vertex data can be interpolated at any point in the interior of a triangle.


TRIANGLES, a dataset directory which contains examples of triangles;

Source Code:

Last revised on 04 May 2020.