utils module

ariastrotools.utils.call_mask(mask)

ariastrotools.utils.create_fits(datadict, header_dict, filename='Avg_neid_data.fits')

Create a multi-extension FITS file from a dictionary of data arrays and headers.

Parameters:

• datadict (dict) –

  Dictionary mapping extension names to their corresponding data.

  The first entry is written as the primary HDU. Remaining entries are written as ImageHDU objects, except those listed in tablehdu, which are written as BinTableHDU objects.

• header_dict (dict) – Dictionary mapping extension names to FITS header information. Each value must be compatible with astropy.io.fits.Header.

• filename (str, optional) – Name of the output FITS file. Default is "Avg_neid_data.fits".

Notes

The function automatically selects BinTableHDU for extensions listed in tablehdu (currently only ACTIVITY). All other extensions are written as ImageHDU objects. Existing files with the same name are overwritten.

Examples

>>> datadict = {
...     "PRIMARY": np.zeros((100, 100)),
...     "SCIENCE": np.random.random((50, 50)),
...     "ACTIVITY": structured_array,
... }
>>> header_dict = {
...     "PRIMARY": {"OBSERVER": "Varghese"},
...     "SCIENCE": {"EXTNAME": "SCIENCE"},
...     "ACTIVITY": {"COMMENT": "Activity indices"},
... }
>>> create_fits(datadict, header_dict, filename="output.fits")

ariastrotools.utils.extract_allexts(fname)

Extract all extensions from a FITS file.

Parameters:

fname (str) – Path to the FITS file.

Returns:

• datadict (dict) – Dictionary mapping extension keywords to numpy arrays containing the data.

• headerdict (dict) – Dictionary mapping extension keywords to FITS headers.

ariastrotools.utils.extract_data_header(hdu, ext=0)

Function to open the fits file and extract the data and header.

ariastrotools.utils.shrink_fits(filename, extensions, replace=False, strict=True)

Shrink a FITS file by retaining data only in selected extensions.

Extensions not listed in extensions are replaced with empty HDUs, preserving their headers and extension names.

Parameters:

• filename (str or pathlib.Path) – Input FITS file.

• extensions (list of str or int) – Extension names and/or extension numbers to retain. The primary HDU (extension 0) is always preserved.

• replace (bool, optional) – If True, overwrite the original file. Otherwise create a new file with suffix .shrink.fits. Default is False.

• strict (bool, optional) – If True (default), raise an exception if any requested extension does not exist. Otherwise, issue a warning and continue.

Returns:

Name of the output FITS file.

Return type:

str