Choice of which particle density (event. matrices) will be calculated and output, in the modelmb particles scheme.
"proton" | 1 | 10
"electron" | 2 | 15
would ask octopus to calculate the density matrix corresponding to the 1st particle (whose coordinates correspond to dimensions 1 to ndim_modelmb), which is an proton, then that corresponding to the 2nd particle (electron with dimensions ndim_modelmb+1 to 2*ndim_modelmb), printing 10 natural orbitals for the first and 15 for the second.
"proton" | 1 | -1
"electron" | 2 | -1
would ask octopus to print out just the densities for particles 1 and 2 without any density matrix output.
states/modelmb_density_matrix.F90 : 106
if (parse_block(namespace, 'DensitytoCalc', blk) /= 0) then