The Absoft Pro Fortran Compiler Suite is the most popular Fortran development kit for Mac OS X.
Fully compatible with OS X 10.4 and OS X 10.3.9 and tuned for G5, Pro Fortran includes an ANSI/ISO Fortran 95 compiler capable of generating both 64-bit and 32-bit executables and C/C++ (32-bit) compiler, all of which are link and debug compatible with Apple C and other tools. Pro Fortran includes a powerful IDE which supports additional compilers and select third party applications such as IMSL and VAST auto parallel and vectorizing tools as plug ins. Stand alone applications can be created with the click of a mouse. Also included are 2D/3Dgraphics, BLAS, ATLAS, LAPACK90 and HDF libraries (some G5 optimized) and free technical support from friendly engineers included at no additional charge. Free standing applications can be created automatically.
G5, G4, or G3 based system [G5 or G4 recommended]
Macintosh OS X 10.3.9 or later for 64-bit or 32-bit code generation
Macintosh OS X 10.4 for executing 64-bit applications