quaternions, a Fortran90 code which carries out some simple arithmetic operations for quaternions.
Rotations in 3D can be represented in a number of ways, including quaternions, a rotation matrix, and a combination of a rotation axis and rotation angle. This library includes functions to convert a rotation from one representation to another, and to apply a rotation to a given vector.
The information on this web page is distributed under the MIT license.
quaternions is available in a C version and a C++ version and a Fortran90 version and a MATLAB version and an Octave version and a Python version.
c8lib, a Fortran90 code which implements certain elementary functions for double precision complex (C8) variables;
complex_numbers_test, a Fortran90 code which demonstrates some simple features involved in the use of complex numbers in MATLAB programming.
i4lib, a Fortran90 code which contains many utility routines, using "I4" or "single precision integer" arithmetic.
r8lib, a Fortran90 code which contains many utility routines, using "R8" or "double precision real" arithmetic.