I8LIB is a FORTRAN77 library which contains a number of utility routines for "I8" or "double precision integer" arithmetic.
The computer code and data files described and made available on this web page are distributed under the GNU LGPL license.
I8LIB is available in a C version and a C++ version and a FORTRAN77 version and a FORTRAN90 version.
C4LIB, a FORTRAN77 library which implements certain elementary functions for "C4" or single precision complex variables;
C8LIB, a FORTRAN77 library which implements certain elementary functions for "C8" or double precision complex variables;
I4LIB, a FORTRAN77 library which contains many utility routines, using "I4" or "single precision integer" arithmetic.
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.
SUBPAK, a FORTRAN77 library which contains many utility routines;
You can go up one level to the FORTRAN77 source codes.