def xi_to_pk(r, xi, ell=0, extrap=False):
r"""
Return a callable function returning the power spectrum multipole of degree
:math:`\ell`, as computed from the Fourier transform of the input :math:`r`
and :math:`\xi_\ell(r)` arrays.
This uses the :mod:`mcfit` package perform the FFT.
Parameters
----------
r : array_like
separation values where ``xi`` is evaluated
xi : array_like
the array holding the correlation function multipole values
ell : int
multipole degree of the input correlation function and the output power
spectrum; monopole by default
extrap : bool, optional
whether to extrapolate the power spectrum with a power law; can improve
the smoothness of the FFT
Returns
-------
InterpolatedUnivariateSpline :
a spline holding the interpolated power spectrum values
"""
P = mcfit.xi2P(r, l=ell, lowring=True)
kk, Pk = P(xi, extrap=extrap)
return InterpolatedUnivariateSpline(kk, Pk)
def _load_p_theta_interp(self, cs2, R):
"""Compute and return an interpolator for :math:`\left[P\ast \Theta\right](k,R_\mathrm{ex})` where is an exclusion window function.
Args:
cs2 (float): Squared-speed-of-sound :math:`c_s^2` counterterm in :math:`(h^{-1}\mathrm{Mpc})^2` units. (Unused if non_linear = False)
R (float): Smoothing scale in :math:h^{-1}`\mathrm{Mpc}`. (Unused if non_linear = False)
Returns:
interp1d: Interpolator for :math:`\left[P\ast \Theta\right]` as a function of exclusion radius. This is evaluated for all k values.
"""
if self.verb: print("Computing interpolation grid for P * Theta convolution")
# Define a k grid
kk = np.logspace(-4,1,10000)
# Define a power spectrum
hm2 = HaloModel(self.cosmology, self.mass_function, self.halo_physics, kk, kh_min = self.kh_min)
pp = hm2.non_linear_power(cs2, R, self.pt_type, self.pade_resum, self.smooth_density, self.IR_resum)
# Transform to real space for convolution
r,xi = P2xi(kk,lowring=False)(pp)
# Define interpolation grid
RR = np.linspace(0,200,1000)
# Multiply in real-space and transform
xi = np.vstack([xi for _ in range(len(RR))])
xi[r.reshape(1,-1)>RR.reshape(-1,1)]=0.
# Interpolate into one dimension and return
kk,pp = xi2P(r,lowring=False)(xi)
int2d = interp2d(kk,RR,pp)
int1d = interp1d(RR,int2d(self.kh_vector,RR).T)
return lambda rr: int1d(rr.ravel())
def xi_to_pk(r, xi, ell=0, extrap=False):
r"""
Return a callable function returning the power spectrum multipole of degree
:math:`\ell`, as computed from the Fourier transform of the input :math:`r`
and :math:`\xi_\ell(r)` arrays.
This uses the :mod:`mcfit` package perform the FFT.
Parameters
----------
r : array_like
separation values where ``xi`` is evaluated
xi : array_like
the array holding the correlation function multipole values
ell : int
multipole degree of the input correlation function and the output power
spectrum; monopole by default
extrap : bool, optional
whether to extrapolate the power spectrum with a power law; can improve
the smoothness of the FFT
Returns
-------
InterpolatedUnivariateSpline :
a spline holding the interpolated power spectrum values
"""
P = mcfit.xi2P(r, l=ell, lowring=True)
kk, Pk = P(xi, extrap=extrap)
return InterpolatedUnivariateSpline(kk, Pk)
def pip_convert(fname, cumulative=False):
## Given a pip file, get the P(k) multipoles.
data = np.loadtxt(fname)
s = data[:,0]
xi0 = data[:,1]
xi2 = data[:,2]
xi4 = data[:,3]
if cumulative:
## ss = np.logspace(np.log(5.), np.log(150.), num=100, base=np.exp(1))
ss = numpy.logspace(-3, 3, num=60, endpoint=False)
A = 1 / (1 + x*x)**1.5
'''
steps = np.diff(np.log(ss))
step = steps[0]
## Interpolate on a grid.
Ci0 = interp1d(s, s ** 3. * xi0, kind='linear', copy=True, bounds_error=False, fill_value=0.0, assume_sorted=False)
Ci2 = interp1d(s, s ** 3. * xi2, kind='linear', copy=True, bounds_error=False, fill_value=0.0, assume_sorted=False)
Ci4 = interp1d(s, s ** 3. * xi4, kind='linear', copy=True, bounds_error=False, fill_value=0.0, assume_sorted=False)
Ci0 = np.sum(Ci0(ss)) * step
Ci2 = np.sum(Ci2(ss)) * step
Ci4 = np.sum(Ci4(ss)) * step
result = []
for nu, phase, CC in zip([0, 2, 4], [1., -1., 1.], [Ci0, Ci2, Ci4]):
print('Solving for nu: %d' % nu)
H1 = mcfit.mcfit(ss, mcfit.kernels.Mellin_SphericalBesselJ(nu - 1, deriv=0), q=0)
H2 = mcfit.mcfit(ss, mcfit.kernels.Mellin_SphericalBesselJ(nu, deriv=0), q=0)
y1, B1 = H1(ss * CC)
y2, B2 = H2(ss * CC / ss)
Pl = 4. * np.pi * phase * (-B1 + (nu + 1.0) * B2 / y2)
result.append(Pl)
'''
return y1, result[0], result[1], result[2]
else:
## New logarithmic r binning.
rs = np.logspace(np.log10(0.2), np.log10(165.), 45, endpoint=True, base=10.)
## Interpolate on a grid.
xi0 = interp1d(s, xi0, kind='linear', copy=True, bounds_error=False, fill_value=0.0, assume_sorted=False)
xi2 = interp1d(s, xi2, kind='linear', copy=True, bounds_error=False, fill_value=0.0, assume_sorted=False)
xi4 = interp1d(s, xi4, kind='linear', copy=True, bounds_error=False, fill_value=0.0, assume_sorted=False)
xi0 = xi0(rs)
xi2 = xi2(rs)
xi4 = xi4(rs)
## And conversion to Fourier.
ks, P0 = xi2P(rs, l=0, lowring=False, deriv=0)(xi0, extrap=False)
ks, P2 = xi2P(rs, l=2, lowring=False, deriv=0)(xi2, extrap=False)
ks, P4 = xi2P(rs, l=4, lowring=False, deriv=0)(xi4, extrap=False)
return ks, P0, P2, P4
Q0 = interp1d(ss,
Q0,
kind='linear',
copy=True,
bounds_error=False,
fill_value=(Q0[0], Q0[-1]),
assume_sorted=False)
Q0 = Q0(s)
xi *= Q0
plt.loglog(k, linb * linb * Plin(k), c='k', linestyle='--')
plt.loglog(k, linb * linb * Pnl(k), c='k')
k, P = xi2P(s)(xi)
plt.loglog(k, linb * linb * P, alpha=0.5, c='tab:blue')
#
for marker, weighted in zip(['s', '^'], [0, 1]):
output_dir = "/global/homes/m/mjwilson/desi/survey-validation/svdc-spring2020f-onepercent/clustering/pk/"
output = os.path.join(output_dir,
"oneper_weighted_{:d}.json".format(weighted))
r = ConvolvedFFTPower.load(output)
poles = r.poles
pl.axhline(r.attrs['shotnoise'], xmin=0.0, xmax=1.0, c='k', alpha=0.3)
## Load linear P(k), lin_pmm.dat
data = np.loadtxt('../dat/lin_pmm.dat')
ks = data[:,0]
P0 = data[:,1]
P0 = interp1d(ks, P0, kind='linear', copy=True, bounds_error=False, fill_value=0.0, assume_sorted=False)
## New logarithmic k binning.
ks = np.logspace(-3.0, np.log10(3.), 45, endpoint=True, base=10.)
P0 = P0(ks)
pl.loglog(ks, P0, 'k-')
rs, x2 = P2xi(ks, l=2)(P0)
ks, P2 = xi2P(rs, l=2)(x2)
pl.loglog(ks, P2, 'k^', markersize=3)
## Noise realisations.
result = []
upper = 25
print rs[upper]
for i in np.arange(3000):
noise = np.copy(x2)
noise[3:upper] += np.random.uniform(0.0, .2 * np.abs(x2[3:upper]), len(x2[3:upper]))
ks, PN = xi2P(rs, l=2)(noise)