The 2LPT code provides initial conditions for running cosmological simulations. It's written in Fortran77 and requires the installation of FFTW version 2.1.5.
See our paper for details on why using this is a good idea...
Changes:
June 23, 2006: FFTW plans changed to integer*8 (for 64 bit, also 32 bit compatible) [Thanks to Mike Santos for pointing out this]
March 19, 2007: bug fixed in definition of hfactor in 2lpt_ic.f, Om0 -> OL0 (this causes a mistake of order 10^-5 in the velocities at z=49) [Thanks to Kohji Yoshikawa for pointing this out]
September 22, 2007: bug fixed in generation of Gaussian field, modes in kx=Nyquist must be complex conjugates
September 24, 2007: Added intel compiler version with dynamic allocation