NAME

Alien::FFTW3 - Alien wrapper for FFTW3

SYNOPSIS

  use strict;
  use warnings;

  use Module::Build;
  use Alien::FFTW3 3.003_002;  # Require fftw v3.3.2 or later

  my $cflags = Alien::FFTW3->cflags;
  my $ldflags = Alien::FFTW3->libs;

  if( Alien::FFTW3->precision('q') ) {
    # compile quad-precision library...
  }

  my $cflags_for_float = Alien::FFTW3->cflags('f');

ABSTRACT

Alien wrapper for FFTW3.

DESCRIPTION

This module provides package validation and installation for FFTW3. It currently depends on the external POSIX program pkg-config to find the FFTW3 libraries.

Because FFTW3 comes in several flavors for different levels of numerical precision, the typical access methods 'cflags' and 'libs' work slightly differently than the simple Alien::Base case. You can feed in nothing at all, in which case you get back cflags and libs strings appropriate for compiling *all* available fftw3 libraries; or you can specify which precision you want by passing in an allowed precision. The allowed precisions are currently 'f','d','l', and 'q' for floats, doubles, long doubles, and quad doubles respecetively.

On initial use, Alien::FFTW3 checks for which precisions are available. If more than zero are available, it succeeds. If none are available, then it fails. If you specify a version number, it is translated from Perl-style version numbers to a POSIX module version string. The load will throw an exception unless every located libfftw external library is at that version or later.

You can query which precisions are installed on your system using the "precision" method, documented below.

As an Alien module, Alien::FFTW3 attempts to build fftw on your system from source if it's not found at install time. Because I'm Lazy, I use the existing Alien::Base infrastructure from Joel Berger to install in that case.

Alien::Base isn't capable of installing the library in a place where the default pkg-config will find it on all systems, so there is some logic to place it in a best guess for where system libraries "should" go on your system: we examine the path searched by pkg-config and place the fftw library in a suitable spot that can be located.

SEE ALSO

Alien::Base, PDL::FFTW3, http://fftw.org

METHODS

precision

Test presence of fftw3 libs with different precisions. Returns a hash ref with keys set to TRUE for each library queried, or undef if none of the queried libraries exist. If you pass in no arguments, all precisions are tested.

The allowed precisions are 'f','d','l', and 'q'.

You can pass them in as an array ref or as a single packed string.

cflags

Returns the cflags compiler flags required for the specified precision, or for all of 'em.

libs

Returns the libs linker flags required for the specified precision, or for all of 'em.