Compile fftw 3.1.2 and 2.1.5

Fftw 3.1.2 compilation is very simple. For the install file, refer

./Configure -- prefix =/home/Eric/fftw -- enable-shared -- enable-threads -- enable-sse2
Make
Make check
Make install

-- Enable-shared is recommended, because this switch is disabled by default, and some programs are linked in the-lfftw mode, so this switch must be added, if you want to specify the compiler and compilation options, as shown in the following code:

./Configure cc = xxx ......

In the new configure version, the compiler is specified in this way, and environment variables are no longer used.

So OK.

Many scientific software actually require fftw 2. x, instead of version 3. Compiling fftw 2 is also very simple. The current stable version is fftw 2.1.5.

./Configure -- help // check which options are available
./Configure -- prefix =/home/Eric/fftw -- enable-shared -- enable-threads -- enable-i386-hacks
Make
Make check
Make install

Here, configure has another -- enable-MPI. I don't think this is necessary, because many fftw-based programs are parallel, and the parallel performance of fftw is not necessarily good here, simply use -- enable-threads to allow fftw to calculate in parallel on a single machine, without much trouble. Open the MPI switch and modify the path of one pair of MPI header files and library files.

Modify the compiler and compile options, as in version 3.x, and define them directly in configure.