Generating Spectra

We provide a number of example scripts in the example directory that demonstrate how to run Spectacle to generate spectra. To get started, first download some example data from the Illustris API:


The main component of spectacle is the spectacle class, which must be instantiated with the location of the hdf5 file containing the particle data:

tacle = spectacle.spectacle(fname='example_data.h5')

We can then load a grid as so:

grid = tacle.load_grid(name='fsps_neb')
grid = tacle.redshift_grid(grid,tacle.redshift)

The most expensive part of the spectra generation is calculating the grid weights. We use the schwimmbad pool syntax to do this flexibly in parallel (we discuss the parallelisation in more detail in FlexPara_). The partial syntax allows us to specify additional arguments to the pool, such as the age and metallicty grid values, and whether we wish to resample. It’s then simply a case of calling and converting the output to an array, before closing the pool.

lg = partial(tacle.weights_grid, Z=grid['metallicity'],
             A=grid['age'][tacle.redshift], resample=True)
weights = np.array(list(,shids)))

Now we have our weights we can use these to directly calculate the intrinsic spectra

intrinsic_spectra = tacle.calc_intrinsic_spectra(weights,grid,z=tacle.redshift)

There are also a number of functions available for applying a dust-screen, using the subhalo properties of each galaxy.