I'm attempting to install atlas via mac ports as it's seems to be almost impossible to compile manually. So, I get this problem, and I have no idea to solve it. Help, please. And, how may I switch to gcc instead of clang building ports?
$ sudo port install atlas
Password:
---> Configuring atlas
Selected C compiler: /usr/bin/clang
Error: org.macports.configure for port atlas returned: Atlas could not detect any fortran compiler. If you really don’t need the fortran interface to be built, please use the +nofortran option, else install a fortran compiler (e.g. gcc4X) before building Atlas.
Please see the log file for port atlas for details:
/opt/local/var/macports/logs/_opt_local_var_macports_sources_rsync.macports.org_release_tarballs_ports_math_atlas/atlas/main.log
To report a bug, follow the instructions in the guide:
http://guide.macports.org/#project.tickets
Error: Processing of port atlas failed
~ sudo port install gcc48
Error: Unable to open port: can't set "compiler.blacklist": couldn't determine build number of compiler "llvm-gcc-4.2"
Your answer is essentially in your question:
"Error: org.macports.configure for port atlas returned: Atlas could not detect any fortran compiler. If you really don’t need the fortran interface to be built, please use the +nofortran option, else install a fortran compiler (e.g. gcc4X) before building Atlas."
So either 'sudo port install atlas +nofortan' or 'sudo port install atlas +gcc48' (for example, or pick your favorite GCC). This will also use the selected gcc for compiling atlas. Some ports (especially those that may have a lot of tubing for particular compilers) will have +gccNN variants available to use a particular compiler.
You will need to 'sudo port clean atlas' first either way as you are changing the variants selection.
EDIT: Be sure to do a 'sudo port selfupdate' as well; I'm not sure what is causing the error on your gcc48 install; hopefully a selfupdate resolves that; you haven't, by chance, upgraded operating systems between MP installs, have you?