split_metadata.py

##############################################################################
# - Creates maps of galaxy counts and galaxy density in each tomographic bin.
##############################################################################

import os
import sys
from configuration import PipelineConfig as PC
from astropy.table import Table
from output_utils import colour_string


# SETTINGS #
config_file = sys.argv[1]
cf = PC(config_file, stage='splitMetadata')


#######################################################
#                  START OF SCRIPT                    #
#######################################################

# Load the metadata
t = Table.read(cf.data_files.metadata)

# Output directory (same as the directory containing the downloaded data)
PATH_OUT = cf.paths.data
# Cycle through the global fields
for fd in cf.fields:
    print(colour_string(fd, 'orange'))

    # Define a mask for selecting data within the bounds of the field
    ra_min, ra_max, dec_min, dec_max = cf.get_field_boundaries(fd)
    if ra_max < ra_min:
        coord_mask = ((t['ra2000'] >= ra_min) | (t['ra2000'] <= ra_max)) * \
            (t['dec2000'] >= dec_min) * (t['dec2000'] <= dec_max)
    else:
        coord_mask = (t['ra2000'] >= ra_min) * (t['ra2000'] <= ra_max) * \
            (t['dec2000'] >= dec_min) * (t['dec2000'] <= dec_max)

    # Determine whether to split the metadata by band (filter)
    if cf.split_by_band:
        for b in cf.bands.all:
            fname = f'{cf.data_files.metadata[:-5]}_{fd}_{b}.fits'

            # Only bother with the next steps if the target file doesn't exist
            if os.path.exists(fname):
                print(f'Metadata file for {fd} in band {b} already exists; '
                      'skipping...')
                continue

            print(b)
            # Mask to select rows using the current filter
            band_mask = (t['filter'] == b)
            # See if other columns might also contain data for this band
            if b in cf.bands.altnames:
                for b_alt in cf.bands.altnames[b]:
                    band_mask |= (t['filter'] == b_alt)
            # Combine with the field mask
            mask = coord_mask * band_mask

            # Save the masked table to the destination file
            t[mask].write(fname, format='fits')

    else:
        fname = f'{cf.data_files.metadata[:-5]}_{fd}.fits'
        # Only bother with the next steps if the target file doesn't exist
        if os.path.exists(fname):
            print(f'Metadata file for {fd} already exists; skipping...')
        else:
            t[coord_mask].write(fname, format='fits')