BEAST Miscellaneous Tools

The following miscellaneous tools are useful for handling data formats and doing assorted data characterization.

Convert hdf5 to FITS

Although the BEAST can read data in various formats, it may be of interest to convert a photometric catalog from hdf5 to FITS format. Below, we show an example for to use the BEAST tool convert_hdf5_to_fits to convert a catalog from hdf5 to FITS and save it to disk:

>>> from beast.tools import convert_hdf5_to_fits 
>>>
>>> # Specify the HDF5 file name
>>> phot_file = 'my_awesome_catalog.hdf5' 
>>>
>>> # Convert the HDF5 file to a FITS file (yay!) and save it to disk
>>> convert_hdf5_to_fits.st_file(file_name = phot_file) 

Observation Depth

The noise model contains completeness information for each filter. The calc_depth_from_completeness tool uses that to find the Vega magnitude (or flux in erg/s/cm^2/A) at which a given completeness is reached. This is useful for evaluating the depth of your observations.

>>> from beast.tools import calc_depth_from_completeness 
>>>
>>> # Find the 50% and 75% completeness for phat_small example
>>> depth = calc_depth_from_completeness.calc_depth(  
        'beast_example_phat_seds.grid.hd5',
        'beast_example_phat_noisemodel.grid.hd5',
        completeness_value=[0.5, 0.75],
        vega_mag=True
    )
>>> # Depth in F275W (Vega mag)
>>> depth['HST_WFC3_F275W'] 
[25.000309202589012, 24.80610510139205]
>>>
>>> # Depth in F814W (Vega mag)
>>> # NaNs show that ASTs don't go deep enough to evaluate 50% completeness
>>> depth['HST_ACS_WFC_F814W'] 
[nan, 24.368742437736692]