Second, multi-core computers are the future. To me, this is the biggest motivation, since I can test software more easily on my desktop (or laptop) machine than on a cluster. Pricing is unknown.Why might you consider installing Open MPI? First, many programs that were designed to run distributed across several computers using MPI can now be run on a multi-core modern desktop computer. This looks promising and should make compiling code developed with xlf much easier to port to OS X. IBM just released a beta xlf compiler.See the High Performance Computing page for more information. This is a smaller and less expensive package than Absoft. The Numerical Algorithms Group has released an OS X version of its fortran95 compiler.At any rate, real*8 is not supported by the altivec vector processor on G4s, so double precision calculations cannot benefit from this feature and are processed by the scalar fpu. Whether that will be worthwhile for your code is something you'll need to decide. Absoft also will bundle tools for automatically 'Altivectorizing' code to make use of the vector processor in G4s.For serious fortran progamming on a Mac, this is the way to go. Absoft also includes AltiVec-optimized LAPACK, BLAS, and IMSL libraries. Absoft puts out a fortran 90/95 compiler for OS X that is also faster than g77 (although it appears not to include O3 optimization (function-inlining), which may sometimes cause lower performance than with g77).The only modern (ie fortran 95) compilers available for the Mac are from three commercial vendors. You can get the latest GCC 3.1, including g77 and lots of other high-performance computing stuff, from Gaurav Khanna's page on High Performance Computing but you'll still want the Apple Developer Tools. The g77 frontend for GCC 2.95 is available from several sources. On my powerbook, the Tools package was on the hard drive, but not installed.

It is freely downloadable from their web site if you did not get it with your computer (eg iMac iBook). Developer Tools comes with all the high-end systems. GCC 2.95 is included in the Apple Developer Tools, but without the g77 frontend. Apple's tools, however, are directed more toward software development than conventional scientific programming.

You can get gfortran and g95 from their web pages, MacPorts, or Fink.Īpple has a page on OS X compilers and other development tools. For current information, go here:Ģ) gfortran - free, part of the GCC compiler suiteģ) g95 - free, splinter project from GCC This page is largely out of date and reflects the optoions in the PowerPC days.

Fortran macos