For given RCN profile r of sample and a grid of purities and ploidies, those pairs for which the tumor ACN profile q fails the non-negativity requirement are removed from the grid
Source:R/make_grid_plus.R
make_grid_plus.Rdmake_grid_plus removes from the grid all pairs of (purity, ploidy) for which the tumor ACN profile q has at least one segment's copy negative; tumor ACN profile q is obtained from the sample RCN profile q and the tumor purity, the tumor ploidy.