MOCASSIN 2.02 manual
MdMg
Syntax
MdMg string1 real1/string2
Description
Dust to gas ratio by mass. If string1 = 'constant' then it must be followed by real1, containing the value of MdMg to be applied homogeneously to all cells in the grid. If string1=file then it must be followed by string2, the name of the file defining the MdMg at each location. Note that MdMg, MdMh and Ndust are mutually exclusive.
This file must consists of four 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 dust to gas mass ratio at the particular grid cell. The x, y and z axis do not to be equally spaces, 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).
It is possible to specify nx, ny and nz from within 'string2' - the first row of the file should then be
# nx ny nz
and the keywords can be omitted from input.in
Default value
.false. 0./'none'