**tetrahedron**,
a C code which
computes properties, including the centroid,
circumsphere, dihedral angles, edge lengths, face angles, face areas,
insphere, quality, solid angles, and volume
of a tetrahedron in 3D.

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

**tetrahedron** is available in
a C version and
a C++ version and
a Fortran90 version and
a MATLAB version and
a Python version.

ellipse, a C code which carries out geometric calculations for ellipses and ellipsoids, including area, distance to a point, eccentricity, perimeter, points along the perimeter, random sampling, conversion between standard and quadratic forms.

geometry, a C code which performs geometric calculations in 2, 3 and N dimensional space.

hypersphere, a C code 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, a C code 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.

triangle, a C code which computes properties, including angles, area, centroid, circumcircle, edge lengths, incircle, orientation, orthocenter, and quality, of a triangle in 2D.

- tetrahedron.c, the source code.
- tetrahedron.sh, compiles the source code.