Using grids from HDF5 files

In the case of large grids, it may in some cases compute once and for all an HDF5 file containing the grid geometry and quantities, and avoid reading it when setting up the rest of the model. This can be done using use_grid_from_file(), for example:

from hyperion.model import Model
m = Model()
...
m.use_grid_from_file('the_grid.hdf5', dust=['kmh.hdf5'])

The first argument should be the name of the HDF5 file, and the dust argument should be a list of dust files to use, one for each dust index in the grid on disk. Once this has been done, you should not set the grid geometry nor call add_density_grid().

The HDF5 file should be in the format that is written by the write methods on grid objects. You can do for example:

from hyperion.grid import CartesianGrid
g = CartesianGrid(...)
# optionally add physical quantities here

then write it out with:

import h5py
f = h5py.File('the_grid.hdf5', 'w')
g.write(f)
f.close()