MOCASSIN 2.02 manual
The density structure of the nebula can be defined cell by cell by using an external density file. MOCASSIN knows that a density file is to be used when the densityFile
string is included in the input file, where
string contains the name and path of the file where the data is stored. This file must consist of four, five or six columns, with the first three columns containing the x-, y-, and z- coordinates of the grid cell in [cm] and the fourth columns containing the value of the hydrogen density by number in [cm-3] at the particular grid cell. The x, y and z axis do not to be equally spaced - irregular grids are perfectly acceptable by MOCASSIN and also the extent of each axis can vary (as long as this is consistent with the values given in the nx, ny and nz fields). The fifth column is optional. If the multiChemistry keyword is specified the fifth column must contain an integer number in the range [1, Ncomponents] which indicates what component this cell belongs to (so that MOCASSIN can assign the chemical abundances for this component).
# nx ny nz
and the keywords can be omitted from