MRIaggr-filtrage3D_cpp: 3D filtering
In bozenne/MRIaggr: Management, Display, and Processing of Medical Imaging Data

C++ function call by calcFilter that performs three dimensional filtering. For internal use.

1 2	filtrage3D_cpp(Vec_data, p_data, Vec_operateur, p_operateur, index_data, bilateral, na_rm)

`Vec_data`	vector of data to which the filter will be applied.
`p_data`	spatial dimensions of the data.
`Vec_operateur`	vector representing the filter to be applied.
`p_operateur`	spatial dimensions of the filter.
`index_data`	index of the non NA data.
`bilateral`	should the influence of each neighbor be ponderated by the difference in signal with the considered observation ?
`na_rm`	should the observations with missing values in their neighbourhood be removed ? Otherwise the ponderation is adjusted.