fn, a FORTRAN77 code which approximates elementary and special functions using Chebyshev polynomials; functions include Airy, Bessel I, Bessel J, Bessel K, Bessel Y, beta, confluent hypergeometric, cosine integral, Dawson's integral, digamma (psi), error, exponential integral, gamma, hyperbolic cosine integral, hyperbolic sine integral, incomplete gamma, log gamma, logarithmic integral, Pochhammer, psi, sine integral, Spence; by Wayne Fullerton.
The original version of the library provided routines for single precision complex, single precision real, and double precision real arguments and used the prefixes "C" and "D" to indicate the complex and double precision versions.
This scheme has been modified for consistency, and also to avoid conflict with the names of functions commonly provided by various compilers. The prefixes "C4_", "R4_" and "R8_" are used to indicate functions for single precision complex, single precision real, and double precision real arguments. For example, the sine function can be calculated by the functions C4_SIN, R4_SIN or R8_SIN.
The original, true, correct version of FN is available through NETLIB: https://www.netlib.org/fn/index.html.
The computer code and data files described and made available on this web page are distributed under the GNU LGPL license.
fn 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.
c4lib, a FORTRAN77 library which implements certain elementary functions for single precision complex variables;
C8LIB, a FORTRAN77 library which implements certain elementary functions for double precision complex variables;
CORDIC, a FORTRAN77 library which uses the CORDIC method to compute certain elementary functions.
F77_INTRINSICS, a FORTRAN77 program which illustrates the use of FORTRAN77 intrinsic functions.
G77_INTRINSICS, a FORTRAN77 program which illustrates the use of intrinsic functions provided by the Gnu G77 compiler.
GFORTRAN_INTRINSICS, a FORTRAN77 program which illustrates the use of intrinsic functions provided by the Gnu GFORTRAN compiler.
MACHAR, a FORTRAN77 library which computes the appropriate values of machine constants for a given machine.
MACHINE, a FORTRAN77 library which stores the appropriate values of machine constants for a given machine.
R4LIB, a FORTRAN77 library which contains many utility routines, using "R4" or "single precision real" arithmetic.
R8LIB, a FORTRAN77 library which contains many utility routines, using "R8" or "double precision real" arithmetic.
SPECFUN, a FORTRAN77 library which computes special functions, including Bessel I, J, K and Y functions, and the Dawson, E1, EI, Erf, Gamma, Psi/Digamma functions.
SPECIAL_FUNCTIONS, a FORTRAN77 library which computes special functions, by Shanjie Zhang, Jianming Jin;
TEST_VALUES, a FORTRAN77 library which supplies test values of various mathematical functions.