class HPGaussSmooth(HParray):
""" adapt an HParray object, and access it via a smoothing Gaussian """
def __init__(self, hparray, sigma_deg):
""" hparray : HParray object
sigma_deg : float
sigma for convolution, in degrees. zero for no change
"""
self.name = hparray.name
self.vec = hparray.vec # note just reference
self.nside = hparray.nside
band = Band(self.nside)
self.dirfun = band.dir
self._indexfun = band.index
self.sigma = np.radians(sigma_deg)
# this guy to give access to basic query_disk (should make the Healpix object accessible in Band)
self.hp = Healpix(self.nside, Healpix.RING, SkyDir.GALACTIC)
def __call__(self, skydir):
if self.sigma == 0: return self.vec[self._indexfun(skydir)]
iv = IntVector()
self.hp.query_disc(skydir, 3 * self.sigma, iv)
sds = map(self.dirfun, iv)
deltas = np.array(map(skydir.difference, sds))
values = np.array(self.vec[list(iv)])
notnan = ~np.isnan(values)
weights = np.array(
map(lambda x: np.exp(-0.5 * (x / self.sigma)**2), deltas[notnan]))
ret = np.dot(values[notnan], weights) / sum(weights)
if np.isnan(ret) or np.isinf(ret):
raise Exception('Bad value at %s' % skydir)
return ret
def average(self, radius=1.0):
""" average over all pixels within radius"""
iv = IntVector()
hp = Healpix(self.nside, Healpix.RING, SkyDir.GALACTIC)
band = Band(self.nside)
newvec = [0] * len(self.vec)
for i in range(len(self.vec)):
hp.query_disc(band.dir(i), np.radians(radius), iv)
newvec[i] = np.array([self.vec[j] for j in iv]).mean()
self.vec = newvec
def finish(self):
hp = Healpix(self.nside,Healpix.RING,SkyDir.EQUATORIAL)
ras,decs = N.asarray( [hp.py_pix2ang(i) for i in xrange(12*self.nside**2)]).transpose()
self.COS_HP_DEC = N.cos(decs)
self.SIN_HP_DEC = N.sin(decs)
self.HP_RA = ras
ra_s,dec_s = self.RA_SCZ,self.DEC_SCZ
ra_z,dec_z = self.RA_ZENITH,self.DEC_ZENITH
self.S_PIX = N.fromiter((hp.py_ang2pix(ra_s[i],dec_s[i]) for i in xrange(len(ra_s))),dtype=int)
self.Z_PIX = N.fromiter((hp.py_ang2pix(ra_z[i],dec_z[i]) for i in xrange(len(ra_z))),dtype=int)
def __init__(self, hparray, sigma_deg):
""" hparray : HParray object
sigma_deg : float
sigma for convolution, in degrees. zero for no change
"""
self.name = hparray.name
self.vec = hparray.vec # note just reference
self.nside = hparray.nside
band = Band(self.nside)
self.dirfun = band.dir
self._indexfun = band.index
self.sigma = np.radians(sigma_deg)
# this guy to give access to basic query_disk (should make the Healpix object accessible in Band)
self.hp = Healpix(self.nside, Healpix.RING, SkyDir.GALACTIC)