GFortran is the name of the GNU Fortran compiler, which is part of the GNU Compiler Collection (GCC). The compiler is free and open-source. More details on the GNU website here.
Since Release 11 (2011), source-code versions of GEMPACK support GFortran as an alternative compiler on Windows PCs. However, since GFortran is rapidly evolving and easy to customize, only the GEMPACK-compatible GFortran downloaded from this page is supported by us for use with source-code GEMPACK.
GFortran is somewhat slower than the Intel compiler -- see this comparison table.
Our GFortran install packages are provided as a convenience to GEMPACK customers. But anyone is free to download them, for whatever use they wish. However, we will only support their use for GEMPACK purposes.
We remind downloaders that GFortran use is covered by the terms of the GNU General Public License. Probably you only need to know about this if you intend to redistribute all or part of GFortran to others.
If you wish to use GFortran for non-GEMPACK purposes, you may well be better off downloading the latest version from the official site.
The install package available below provides GFortran which makes both 32-bit and 64-bit programs. After GFortran is installed you will install Source-code GEMPACK. During the installation of Source-code GEMPACK you must choose whether to use 32-bit or 64-bit GFortran. If you are using 32-bit Windows you can only choose 32-bit GFortran. If you are using 64-bit Windows you may choose to use either 32-bit or 64-bit GFortran. The only advantage of the 64-bit version is that you can solve very large models; the disadvantage is that you cannot share your TABLO-generated model EXE files with people who run 32-bit Windows. With the 32-bit version, your model cannot use more than 4GB of RAM, but you will produce EXE files that run on either 32-bit or 64-bit Windows.
Download the GEMPACK compatible GFortran install package:
Administrator rights are needed for the installation. When downloaded, run the simple install program. The installation directroy may be modified, but we recommend you accept the default C:\MinGW-w64. The installer will put the installation directory on the system path.
Finally, reboot the PC. Some users have found that GFortran compiles very slowly the first time it is used. The problem seems to disappear after rebooting.
Before installing GEMPACK, you should test your installation of GFortran as follows. Right click and choose "Save Link As" or "Save Target As" depending on your browser, to save the small program hello.for into a temporary folder, say C:\test. When compiled and executed this program will write "Hello World" to the terminal. Next, open a command prompt in the C:\test folder (containing hello.for). To test the 32-bit GFortran installation, type the following commands.
C:\test>gfortvars ia32 C:\test>gfortran hello.for -o hello.exe C:\test>hello
To test the 64-bit installation (this only works on 64-bit Windows), type the following commands:
C:\test>gfortvars intel64 C:\test>gfortran hello.for -o hello.exe C:\test>hello
The first command, gfortvars ia32 (or gfortvars intel64), sets up the environment for the compiler. The second command, gfortran hello.for -o hello.exe, compiles the program hello.exe. And the third command, hello, runs the hello.exe program which will write the words "Hello World" to the terminal. If you see "Hello World" then your compiler installation is working.
See also: