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SHCrossPowerSpectrumDensity

Compute the cross-power spectral density of two real functions.

Usage

call SHCrossPowerSpectrumDensity (cilm1, cilm2, lmax, cspectrum)

Parameters

cilm1 : input, real*8, dimension (2, lmaxin1+1, lmaxin1+1)
The first function expressed in real spherical harmonics.
cilm2 : input, real*8, dimension (2, lmaxin2+1, lmaxin2+1)
The second function expressed in real spherical harmonics.
lmax : input, integer
The maximum spherical harmonic degree to calculate the cross-power spectral density. This must be less than or equal to the minimum of lmaxin1 and lmaxin2.
cspectrum : output, real*8, dimension (lmax+1)
The cross-power spectral density of the two functions.

Description

SHCrossPowerSpectrumDensity will calculate the cross-power spectral density of two functions expressed in real spherical harmonics. For a given spherical harmonic degree l, this is explicitly calculated as:

cspectrum(l) = Sum_{i=1}^2 Sum_{m=0}^l cilm1(i, l+1, m+1) * cilm2(i, l+1, m+1) / (2l + 1).

See also

shpowerl, shpowerdensityl, shcrosspower, shcrosspowerdensityl, shpowerspectrum, shpowerspectrumdensity, shcrosspowerspectrum, shadmitcorr

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