def harmonic_sphere_map_from_fits(filename, extno=1, fitsformat='healpix', dtype=np.cdouble):
if fitsformat != 'healpix':
raise NotImplementedError()
import pyfits
hdulist = pyfits.open(filename)
try:
ext = hdulist[extno]
lmin = ext.header['MIN-LPOL']
lmax = ext.header['MAX-LPOL']
out = harmonic_sphere_map(0, lmin, lmax, is_complex=True)
ls = broadcast_l_to_lm(np.arange(lmin, lmax + 1), lmin)
ms = m_range_lm(lmin, lmax)
running_index = ls**2 + ls + ms + 1
index = ext.data.field(0).ravel()
alm_real = ext.data.field(1).ravel()
alm_imag = ext.data.field(2).ravel()
# If Cythonizing this we can make it fast anyway and loose the special case
if np.all(running_index == index):
out.real = alm_real
out.imag = alm_imag
else:
raise NotImplementedError('Too lazy to implement non-contiguous indices')
finally:
hdulist.close()
return out
def to_fits(self, filename, fitsformat='healpix', dataformat=None):
if self.format is not COMPLEX_BRIEF:
self.to_complex().to_fits(filename, fitsformat=fitsformat, dataformat=dataformat)
return
if fitsformat != 'healpix':
raise NotImplementedError()
if dataformat is None:
if self.dtype == np.cdouble:
dataformat = 'D'
elif self.dtype == np.csingle:
dataformat = 'E'
else:
raise NotImplementedError()
import pyfits
import os
if self.ndim != 1:
raise NotImplementedError()
if os.path.exists(filename):
os.unlink(filename)
ls = broadcast_l_to_lm(np.arange(self.lmin, self.lmax + 1), self.lmin)
ms = m_range_lm(self.lmin, self.lmax)
index = ls**2 + ls + ms + 1
cols = pyfits.ColDefs([
pyfits.Column(name='index=l^2+l+m+1', array=index, format='J'), # 4-byte int
pyfits.Column(name='alm (real)', array=self.real, format=dataformat),
pyfits.Column(name='alm (imaginary)', array=self.imag, format=dataformat)])
tab = pyfits.new_table(cols)
tab.header.update('MIN-LPOL', self.lmin)
tab.header.update('MAX-LPOL', self.lmax)
tab.header.update('MAX-MPOL', self.lmax)
pyfits.HDUList([pyfits.PrimaryHDU(), tab]).writeto(filename)