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External module function *chargedensity_coeff* -
used by *densplt*,
*spins*,
*display_density*,*display_densities*

In order to calculate the chargedensity, the expansion coefficients
have to be evaluated and
the following function has to be present in the module file **.so*:

extern "C" void chargedensity_coeff(Vector & cd,double * T, Vector & Hxc, Vector & Hext,
double * gJ, Vector & MODPAR,
char ** sipffilename, ComplexMatrix & Icalc_parstorage);

it works exactly as *mcalc* with the only modification
that the vector cd has 28 components, therefore we do not give more details here.

The module function must perform the following task:

- calculate the coefficients of
in the expansion of
the charge density in equation (175).
The output Vector cd(1,...,28) should contain coefficients
(i.e.
)
in the following order (lm): 00, 2-2, 2-1,20,21,22, 4-4, 4-3,..,44,6-6,6-5 ...,65,66
- if all quantities should be evaluated assuming that all Boltzmann probabilities
are zero except for the state number , for which the probability .

Martin Rotter
2017-01-10