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(fftw.info)Installing FFTW in both single and double precision

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Installing FFTW in both single and double precision
===================================================

   It is often useful to install both single- and double-precision
versions of the FFTW libraries on the same machine, and we provide a
convenient mechanism for achieving this on Unix systems.

   When the `--enable-type-prefix' option of configure is used, the
FFTW libraries and header files are installed with a prefix of `d' or
`s', depending upon whether you compiled in double or single precision.
Then, instead of linking your program with `-lrfftw -lfftw', for
example, you would link with `-ldrfftw -ldfftw' to use the
double-precision version or with `-lsrfftw -lsfftw' to use the
single-precision version.  Also, you would `#include' `<drfftw.h>' or
`<srfftw.h>' instead of `<rfftw.h>', and so on.

   *The names of FFTW functions, data types, and constants remain
unchanged!*  You still call, for instance, `fftw_one' and not
`dfftw_one'.  Only the names of header files and libraries are
modified.  One consequence of this is that *you cannot use both the
single- and double-precision FFTW libraries in the same program,
simultaneously,* as the function names would conflict.

   So, to install both the single- and double-precision libraries on the
same machine, you would do:

     ./configure --enable-type-prefix [ other options ]
     make
     make install
     make clean
     ./configure --enable-float --enable-type-prefix [ other options ]
     make
     make install