コード例 #1
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def test_nody():
    """ Checking end to end nbody
  """
    a0 = 0.1

    pm = ParticleMesh(BoxSize=bs, Nmesh=[nc, nc, nc], dtype='f4')
    grid = pm.generate_uniform_particle_grid(shift=0).astype(np.float32)
    solver = Solver(pm, Planck15, B=1)
    stages = np.linspace(0.1, 1.0, 10, endpoint=True)

    # Generate initial state with fastpm
    whitec = pm.generate_whitenoise(100, mode='complex', unitary=False)
    lineark = whitec.apply(lambda k, v: Planck15.get_pklin(
        sum(ki**2 for ki in k)**0.5, 0)**0.5 * v / v.BoxSize.prod()**0.5)
    statelpt = solver.lpt(lineark, grid, a0, order=1)
    finalstate = solver.nbody(statelpt, leapfrog(stages))
    final_cube = pm.paint(finalstate.X)

    # Same thing with flowpm
    tlinear = tf.expand_dims(np.array(lineark.c2r()), 0)
    state = tfpm.lpt_init(tlinear, a0, order=1)
    state = tfpm.nbody(state, stages, nc)
    tfread = pmutils.cic_paint(tf.zeros_like(tlinear), state[0]).numpy()

    assert_allclose(final_cube, tfread[0], atol=1.2)
コード例 #2
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def get_lpt(pm, z, cosmology, seed):
    """Evolve the linear power using a 2LPT solver,
       so we get a good model of the density structure at the reionization redshift."""
    a = 1 / (1 + z)
    Plin = LinearPower(cosmology, redshift=0, transfer='EisensteinHu')
    solver = Solver(pm, cosmology, B=1)
    Q = pm.generate_uniform_particle_grid()

    wn = solver.whitenoise(seed)
    dlin = solver.linear(wn, Plin)

    state = solver.lpt(dlin, Q, a=a, order=2)

    return state
コード例 #3
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    def __init__(self,
                 linear,
                 astart=0.1,
                 aend=1.0,
                 boost=2,
                 Nsteps=5,
                 cosmo=None):
        self.comm = linear.comm

        if cosmo is None:
            cosmo = linear.Plin.cosmo

        self.cosmo = cosmo

        # the linear density field mesh
        self.linear = linear

        self.attrs.update(linear.attrs)

        asteps = numpy.linspace(astart, aend, Nsteps)
        self.attrs['astart'] = astart
        self.attrs['aend'] = aend
        self.attrs['Nsteps'] = Nsteps
        self.attrs['asteps'] = asteps
        self.attrs['boost'] = boost

        solver = Solver(self.linear.pm, cosmology=self.cosmo, B=boost)
        Q = self.linear.pm.generate_uniform_particle_grid(shift=0.5)

        self.linear = linear

        dlin = self.linear.to_field(mode='complex')
        state = solver.lpt(dlin, Q, a=astart, order=2)
        state = solver.nbody(
            state,
            leapfrog(numpy.linspace(astart, aend, Nsteps + 1, endpoint=True)))

        H0 = 100.
        self.RSD = 1.0 / (H0 * aend * self.cosmo.efunc(1.0 / aend - 1))

        self._size = len(Q)
        CatalogSource.__init__(self, comm=linear.comm, use_cache=False)

        self._csize = self.comm.allreduce(self._size)

        self['Displacement'] = state.S
        self['InitialPosition'] = state.Q
        self['ConjugateMomentum'] = state.P  # a ** 2  / H0 dx / dt
コード例 #4
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def test_lpt_init():
    """
  Checking lpt init
  """
    a0 = 0.1

    pm = ParticleMesh(BoxSize=bs, Nmesh=[nc, nc, nc], dtype='f4')
    grid = pm.generate_uniform_particle_grid(shift=0).astype(np.float32)
    solver = Solver(pm, Planck15, B=1)

    # Generate initial state with fastpm
    whitec = pm.generate_whitenoise(100, mode='complex', unitary=False)
    lineark = whitec.apply(lambda k, v: Planck15.get_pklin(
        sum(ki**2 for ki in k)**0.5, 0)**0.5 * v / v.BoxSize.prod()**0.5)
    statelpt = solver.lpt(lineark, grid, a0, order=1)

    # Same thing with flowpm
    tlinear = tf.expand_dims(np.array(lineark.c2r()), 0)
    tfread = tfpm.lpt_init(tlinear, a0, order=1).numpy()

    assert_allclose(statelpt.X, tfread[0, 0] * bs / nc, rtol=1e-2)
コード例 #5
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def test_solver(comm):
    pm = ParticleMesh(BoxSize=512., Nmesh=[8, 8, 8], comm=comm)
    solver = Solver(pm, Planck15, B=1)

    P_prm = Planck15.Primordial.get_pkprim

    tf = get_species_transfer_function_from_class(Planck15, 9)

    Q = pm.generate_uniform_particle_grid(shift=0)

    wn = solver.whitenoise(1234)
    prm = solver.primordial(wn, P_prm)
    ic = solver.lpt(prm, {
                '0': (Baryon, tf['d_b'], tf['dd_b']),
                '1': (CDM, tf['d_cdm'], tf['dd_cdm']),
                '4': (NCDM, tf['d_ncdm[0]'], tf['dd_ncdm[0]']),
            }, Q, a=0.1)

    print('0', ic.species['0'].S[0], ic.species['0'].P[0], ic.species['0'].Q[0])
    print('1', ic.species['1'].S[0], ic.species['1'].P[0], ic.species['1'].Q[0])
    print('4', ic.species['4'].S[0], ic.species['4'].P[0], ic.species['4'].Q[0])

    c2 = CoreSolver(pm, Planck15, B=1)
    Pk = lambda k: Planck15.get_pk(k, z=0)
    dlin = c2.linear(wn, Pk)
    ic2 = c2.lpt(dlin, Q, 0.1, order=1)
    print(ic2.S[0], ic2.P[0], ic2.Q[0])
    final2 = c2.nbody(ic2, leapfrog([0.1, 1.0]))

    final = solver.nbody(ic, leapfrog([0.1, 1.0]))
    print('0', final.species['0'].F[0])
    print('1', final.species['1'].F[0])
    print('4', final.species['4'].F[0])
    print(final2.F[0])

    final.to_catalog()
コード例 #6
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def test_solver():
    Plin = LinearPower(Planck15, redshift=0, transfer='EisensteinHu')
    solver = Solver(pm, Planck15, B=1)
    Q = pm.generate_uniform_particle_grid(shift=0)

    wn = solver.whitenoise(1234)
    dlin = solver.linear(wn, lambda k: Plin(k))

    state = solver.lpt(dlin, Q, a=1.0, order=2)

    dnonlin = solver.nbody(state, leapfrog([1.0]))

    dnonlin.save('nonlin')
コード例 #7
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    def solve(pm):
        solver = Solver(pm, Planck15, B=1)
        q = numpy.array_split(Q, pm.comm.size)[pm.comm.rank]
        wn = solver.whitenoise(1234)
        dlin = solver.linear(wn, lambda k: Plin(k))

        state = solver.lpt(dlin, q, a=0.1, order=2)
        state = solver.nbody(state, leapfrog([0.1, 0.5, 1.0]))

        d = {}
        for key in 'X', 'P', 'F':
            d[key] = numpy.concatenate(pm.comm.allgather(getattr(state, key)),
                                       axis=0)
        return d
コード例 #8
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def test_lpt():
    Plin = LinearPower(Planck15, redshift=0, transfer='EisensteinHu')
    solver = Solver(pm, Planck15, B=1)
    Q = pm.generate_uniform_particle_grid(shift=0)

    wn = solver.whitenoise(1234)
    dlin = solver.linear(wn, lambda k: Plin(k))

    state1 = solver.lpt(dlin, Q, a=0.01, order=1)
    state2 = solver.lpt(dlin, Q, a=1.0, order=1)

    pt = MatterDominated(Planck15.Om0, a=[0.01, 1.0], a_normalize=1.0)
    #    print((state2.P[...] / state1.P[...]))
    print((state2.P[...] - state1.P[...]) / state1.F[...])

    fac = 1 / (0.01**2 * pt.E(0.01)) * (pt.Gf(1.0) - pt.Gf(0.01)) / pt.gf(0.01)
    assert_allclose(state2.P[...], state1.P[...] + fac * state1.F[...])
コード例 #9
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from nbodykit.algorithms.fof import FOF
from nbodykit.algorithms.fftpower import FFTPower
from nbodykit.source import ArrayCatalog

from pmesh.pm import ParticleMesh
import numpy

pm = ParticleMesh(BoxSize=512,
                  Nmesh=[256, 256, 256],
                  dtype='f8',
                  resampler='tsc')
Q = pm.generate_uniform_particle_grid()

stages = numpy.linspace(0.1, 1.0, 20, endpoint=True)

solver = Solver(pm, Planck15, B=2)
solver_ncdm = SolverNCDM(pm, Planck15, B=2)

wn = solver.whitenoise(400)
dlin = solver.linear(wn, EHPower(Planck15, 0))
lpt = solver.lpt(dlin, Q, stages[0])
#lpt.S = numpy.float32(lpt.S)


def monitor(action, ai, ac, af, state, event):
    if pm.comm.rank == 0:
        print(state.a['S'], state.a['P'], state.a['F'], state.S[0], state.P[0],
              action, ai, ac, af)


state1 = solver.nbody(lpt.copy(), leapfrog(stages), monitor=monitor)
コード例 #10
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from nbodykit.algorithms.fftpower import FFTPower
from nbodykit.source import ArrayCatalog, MultipleSpeciesCatalog
from fastpm.multi import get_species_transfer_function_from_class

from pmesh.pm import ParticleMesh
import numpy

Planck15 = Planck15.clone(gauge='newtonian')

pm = ParticleMesh(BoxSize=512, Nmesh=[64, 64, 64], dtype='f4', resampler='tsc')
Q = pm.generate_uniform_particle_grid()

stages = numpy.linspace(0.1, 1.0, 10, endpoint=True)
#stages = [1.]

solver = Solver(pm, Planck15, B=2)
solver_multi = SolverMulti(pm, Planck15, B=2)

wn = solver.whitenoise(400, unitary=True)
dlin = solver.linear(wn, LinearPower(Planck15, 0))
lpt = solver.lpt(dlin, Q, stages[0], order=2)


def monitor(action, ai, ac, af, state, event):
    if pm.comm.rank == 0:
        print(state.a['S'], state.a['P'], state.a['F'], state.S[0], state.P[0],
              action, ai, ac, af)


def monitor_multi(action, ai, ac, af, state, event):
    if pm.comm.rank == 0:
コード例 #11
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ファイル: fastpmSim.py プロジェクト: biweidai/LDL
    k[mask] = 1.
    delta = np.interp(np.log10(k), logk, logpower)
    power = norm * (10**delta) * (2 * np.pi**2) / k**3
    power[mask] = 0.
    k[mask] = 0.
    return power


#time steps in scale factor
stages = np.linspace(0.1, 1., args.Nstep, endpoint=True)

a_output = 1. / (np.array(args.output_redshift) + 1.)

#IC 2LPT
t = time.time()
solver_IC = Solver(pm_IC, Planck15, B=2)
wn = solver_IC.whitenoise(2695896)
dlin = solver_IC.linear(wn, Power)

Q = pm.generate_uniform_particle_grid(shift=0)
solver = Solver(pm, Planck15, B=2)
state = solver.lpt(dlin, Q, stages[0], order=2)

if pm.comm.rank == 0:
    print('Finish generating initial conditions with 2LPT. Time:',
          time.time() - t)

X0 = state.X
V0 = state.V
a0 = np.array(stages[0])
コード例 #12
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RG = args.RG
Ng = args.Ng
Lbox = args.Lbox
print("Seed = ", Rdm_seed)
print("Lbox = %.1f" % Lbox, "Ng = %d" % Ng, "RG = %.2f" % RG)

# Choose cosmology
# -------------------------------------------
cosmology = nbcosmos.WMAP9
mycosmo = Cosmos(FLRW=True, obj=cosmology)

# generate linear density field at z=0
# -------------------------------------------
pm = ParticleMesh(BoxSize=Lbox, Nmesh=[Ng, Ng, Ng])
Q = pm.generate_uniform_particle_grid(shift=0)
solver = Solver(pm, cosmology, B=1)

wn = solver.whitenoise(seed=Rdm_seed)
dlin = solver.linear(wn, lambda k: mycosmo.Pk_lin(k))
dx_field = dlin.c2r(
).value  # dx_field is the density contrast field centered at 0

# initialize gsCR object, build xij^{-1} matrix for full 18 constraints
# -------------------------------------------
fg = gsCR(mycosmo, Lbox=Lbox, Nmesh=Ng, RG=RG, CONS=['full'])
fg.build_Xij_inv_matrix()
print("xij^{-1}:")
print(fg.xij_tensor_inv)
print("*********************************************")

# set peak position
コード例 #13
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ファイル: saveIC.py プロジェクト: yueyingn/gaussianCR
def saveIC_bt2(IC_path, dx_field, Lbox, Ng, cosmology, redshift=99):
    """
    Use Zel-dovich approximation to back-scale the linear density field to initial redshift,
    paint baryon and dm particles from the grid,
    and save initial condition in MP-Gadget/bluetides-ii format
    
    
    Parameters
    ---------
    : dx_field  : linear density field at z=0
    : Lbox      : BoxSize, in Mpc/h, will be converted to kpc/h in the IC output
    : Ng        : Number of grid on which to paint the particle
    : cosmology : nbodykit.cosmology, or astropy.cosmology.FLRW
    : redshift  : redshift of the initial condition
    """

    mesh = ArrayMesh(dx_field,
                     BoxSize=Lbox)  # density contrast field centered at zero
    dk_field = mesh.compute(mode='complex')

    shift_gas = -0.5 * (cosmology.Om0 - cosmology.Ob0) / cosmology.Om0
    shift_dm = 0.5 * cosmology.Ob0 / cosmology.Om0

    pm = ParticleMesh(BoxSize=Lbox, Nmesh=[Ng, Ng, Ng])
    solver = Solver(pm, cosmology, B=1)

    Q_gas = pm.generate_uniform_particle_grid(shift=shift_gas)
    Q_dm = pm.generate_uniform_particle_grid(shift=shift_dm)

    scale_a = 1. / (1 + redshift)
    state_gas = solver.lpt(dk_field, Q_gas, a=scale_a,
                           order=1)  # order = 1 : Zel-dovich
    state_dm = solver.lpt(dk_field, Q_dm, a=scale_a, order=1)

    state = state_dm
    with FileMPI(state.pm.comm, IC_path, create=True) as ff:

        m0 = state.cosmology.rho_crit(0) * state.cosmology.Omega0_b * (
            Lbox**3) / state.csize
        m1 = state.cosmology.rho_crit(0) * (
            state.cosmology.Om0 - state.cosmology.Omega0_b) * (Lbox**
                                                               3) / state.csize

        with ff.create('Header') as bb:
            bb.attrs['BoxSize'] = Lbox * 1000
            bb.attrs['HubbleParam'] = state.cosmology.h
            bb.attrs['MassTable'] = [m0, m1, 0, 0, 0, 0]

            bb.attrs['OmegaM'] = state.cosmology.Om0
            bb.attrs['OmegaB'] = state.cosmology.Omega0_b
            bb.attrs['OmegaL'] = state.cosmology.Omega0_lambda

            bb.attrs['Time'] = state.a['S']
            bb.attrs['TotNumPart'] = [state.csize, state.csize, 0, 0, 0, 0]

        ff.create_from_array('1/Position',
                             1000 * periodic_wrap(state.X, Lbox))  # in kpc/h
        ff.create_from_array(
            '1/Velocity',
            state.V / np.sqrt(state.a['S']))  # old gadget convention for IC
        dmID = np.arange(state.csize)
        ff.create_from_array('1/ID', dmID)

        #######################################################
        ff.create_from_array('0/Position',
                             1000 * periodic_wrap(state_gas.X, Lbox))
        ff.create_from_array('0/Velocity', state_gas.V / np.sqrt(state.a['S']))
        gasID = np.arange(state.csize, 2 * state.csize)
        ff.create_from_array('0/ID', gasID)

    print("IC generated!")
    print("*********************************************")
    return state
コード例 #14
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    wnk = fastpm.as_complex_field(x, pm)

    rhok = fastpm.induce_correlation(wnk, powerspectrum, pm)
    dx1, dx2 = fastpm.lpt(rhok, q, pm)
    dx, p, f = fastpm.nbody(rhok, q, [0.1, 0.6, 1.0], Planck15, pm)
    dx0, p0, f0 = fastpm.nbody(rhok, q, [0.1], Planck15, pm)
    model.output(dx1=dx1, dx2=dx2, dx=dx, p=p, dx0=dx0, p0=p0, f0=f0, f=f)

wn = pm.generate_whitenoise(555, unitary=True)
x = wn[...]

x = numpy.stack([x.real, x.imag], -1)

from fastpm.core import Solver, leapfrog

solver = Solver(pm, Planck15, B=1)
linear = solver.linear(wn, powerspectrum)

dx1_f = lpt1(linear, q)
dx2_f = lpt1(lpt2source(linear), q)
lpt = solver.lpt(linear, Q=q, a=0.1)

print('comparing lpt order by order')

dx1, dx2 = model.compute(['dx1', 'dx2'], init=dict(x=x))

print('model', dx1.std(axis=0), dx2.std(axis=0))
print('fastpm', dx1_f.std(axis=0), dx2_f.std(axis=0))
print('model', dx1[0], dx2[0])
print('fastpm', dx1_f[0], dx2_f[0])
コード例 #15
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Lbox = args.Lbox
print ("Seed = ",Rdm_seed)
print ("Lbox = %.1f"%Lbox,"Ng = %d"%Ng,"RG = %.2f"%RG)


# Choose cosmology
# -------------------------------------------
cosmology = nbcosmos.WMAP9
mycosmo = Cosmos(FLRW=True,obj=cosmology)


# generate linear density field at z=0 
# -------------------------------------------
pm = ParticleMesh(BoxSize=Lbox, Nmesh=[Ng,Ng,Ng])
Q = pm.generate_uniform_particle_grid(shift=0)
solver = Solver(pm,cosmology,B=1)

wn = solver.whitenoise(seed = Rdm_seed)
dlin = solver.linear(wn, lambda k: mycosmo.Pk_lin(k))
dx_field = dlin.c2r().value # dx_field is the density contrast field centered at 0


# initialize gsCR object, build xij^{-1} matrix for full 18 constraints
# -------------------------------------------
fg = gsCR(mycosmo,Lbox=Lbox,Nmesh=Ng,RG=RG,CONS=['full'])
fg.build_Xij_inv_matrix()
print ("xij^{-1}:")
print (fg.xij_tensor_inv)
print ("*********************************************")

コード例 #16
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def func_gal_catalogue(bs, nc, seed, nstep, seed_hod, Omega_m, p_alpha,
                       p_logMin, p_logM1, p_logM0, p_sigma_logM):

    folder = "L%04d_N%04d_S%04d_%02dstep" % (bs, nc, seed, nstep)

    # setup initial conditions
    Omegacdm = Omega_m - 0.049,
    cosmo = cosmology.Planck15.clone(Omega_cdm=Omegacdm,
                                     h=0.6711,
                                     Omega_b=0.049)
    power = cosmology.LinearPower(cosmo, 0)
    klin = np.logspace(-4, 2, 1000)
    plin = power(klin)
    pkfunc = interpolate(klin, plin)

    # run the simulation
    pm = ParticleMesh(BoxSize=bs, Nmesh=[nc, nc, nc])
    Q = pm.generate_uniform_particle_grid()
    stages = numpy.linspace(0.1, 1.0, nstep, endpoint=True)
    solver = Solver(pm, cosmo, B=2)
    wn = solver.whitenoise(seed)
    dlin = solver.linear(wn, pkfunc)
    state = solver.lpt(dlin, Q, stages[0])
    state = solver.nbody(state, leapfrog(stages))

    # create the catalogue
    cat = ArrayCatalog(
        {
            'Position': state.X,
            'Velocity': state.V,
            'Displacement': state.S,
            'Density': state.RHO
        },
        BoxSize=pm.BoxSize,
        Nmesh=pm.Nmesh,
        M0=Omega_m * 27.75e10 * bs**3 / (nc / 2.0)**3)
    cat['KDDensity'] = KDDensity(cat).density
    cat.save('%s/Matter' % (folder),
             ('Position', 'Velocity', 'Density', 'KDDensity'))

    # run FOF
    fof = FOF(cat, linking_length=0.2, nmin=12)
    fofcat = fof.to_halos(particle_mass=cat.attrs['M0'],
                          cosmo=cosmo,
                          redshift=0.0)
    fofcat.save('%s/FOF' % (folder),
                ('Position', 'Velocity', 'Mass', 'Radius'))

    # run HOD
    params = {
        'alpha': p_alpha,
        'logMmin': p_logMin,
        'logM1': p_logM1,
        'logM0': p_logM0,
        'sigma_logM': p_sigma_logM
    }
    halos = HaloCatalog(fofcat, cosmo=cosmo, redshift=0.0, mdef='vir')
    halocat = halos.to_halotools(halos.attrs['BoxSize'])
    hod = HODCatalog(halocat, seed=seed_hod, **params)

    hod.save('%s/HOD' % (folder), ('Position', 'Velocity'))

    return folder, cat, fofcat, hod