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dhaj.doc
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Compute the latitudinal weights used in the Driscoll and Healy (1994) spherical
harmonic transform.
Usage
-----
aj = DHaj (n, [extend])
Returns
-------
aj : float, dimension (n) or (n+1)
The latitudinal weights used in the spherical harmonic transform.
Parameters
----------
n : integer
The number of samples in latitude used in the spherical harmonic transform.
This must be even.
extend : input, optional, bool, default = False
If True, include the latitudinal band for 90 S, which increases the
dimension of aj by 1.
Description
-----------
DHaj will calculate the latitudinal weights used in the spherical harmonic
transform of Driscoll and Healy (1994; equation 9). The number of samples n must
be even, and the transform and its inverse are implemented as SHExpandDH and
MakeGridDH, respectively. It is noted that the first element, corresponding to
the north pole, is always zero. The element corresponding to the south pole is
not included by default, but can be returned by specifying extend.
Reference
---------
Driscoll, J.R. and D.M. Healy, Computing Fourier transforms and convolutions on
the 2-sphere, Adv. Appl. Math., 15, 202-250, 1994.