Workflow:

sb_transfer
	-> sb_calc_stiff
		-> calc_stiff_matrix_val
	-> sb_find_elec
	-> sb_calc_vecx
		-> sb_set_bndcon
		-> sb_solve

sb_calc_gain %still todo
	-> sb_rhs_venant

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Used functions:

sb_transfer

Calculate transfer matrix out of given wireframe, electrode positions (and tissue conductivities).

sb_transfer -> sb_calc_stiff

Calculate stiffness matrix out of given wireframe consisting of nodes, elements, conductivity-field.

sb_calc_stiff -> calc_stiff_matrix_val

fortran function calculating the stiffness matrix
%TODO: add documentation to the source code

sb_transfer -> sb_find_elec

Find wireframe nodes corresponding to electrode positions.

sb_transfer -> sb_calc_vecx

Calculate solution vector out of gifen stiffness matrix, right-hand-side vector vecb and dirichlet-node.
%ALTERNATIVE:
sb_calc_vecx_fort
same function/slightly different input, uses fortran solver to compute the solution, is faster then sb_calc_vecx

sb_rhs_venant

Calculate rhs for venant approach.
%TODO: optimize implementation, function is still relatively slow

sb_rhs_venant -> sb_calc_ven_loads

Calculates the loads for the venant approach.

