def __init__(self, cl, res, lsides, with_pixwin=False):
assert len(res) == len(lsides) and len(res) == 2
self.cl = cl
self.res = res
self.shape = (2 ** res[0], 2 ** res[1])
self.lsides = lsides
self.lib_cube = cube.library_datacube(res, lsides, verbose=False)
self._w_pixwin = with_pixwin
super(circulant2d_fromcl, self).__init__(self.get_spec_mat(), self.shape, lsides)
def spec_mat_from_cl(cl, res, lsides):
"""
Common routine to build spectral matrix from cl. Input are squared frequencies, the cl vector,
the resolution res (N = 2**res) of the box, and the side lengths.
"""
assert len(res) == len(lsides)
for r in res : assert r < 16,'Do you really want 2**16 points ?? '+ str(r)
# TODO : Frankly, this is cheap. You can do better, come on.
# TODO : It might actually be OK. but the zeroth mode definitely needs some adjustement.
# TODO : do that by computing truncated integrals of legendre pol.
lib_cub = cube.library_datacube(res, lsides)
k_sqd = lib_cub.sqd_freqmap()
return np.interp(np.sqrt(k_sqd), np.arange(len(cl)), cl / lib_cub.cell_vol(), left=0., right=0.)