pycfitsio: Python ctypes wrapper for cfitsio

Features

• read binary tables using hdu and column names into simple dictionaries of arrays
• write FITS files incrementally 1 HDU at a time

Requirements

pycfitsio requires the dynamic library cfitsio, in linux it usually packaged as libcfitsio-dev

Install

pip install pycfitsio #stable version

# for development version clone from github and run python setup.py install

Examples

Reading

>>> f = pycfitsio.open("debug/data.fits")

>>> hdulist = f.HDUs

>>> print(hdulist)
OrderedDict([('DATA', HDU: DATA)])

>>> hdu = f['DATA']

>>> column_array = f['DATA'].read_column('signal')

>>> all_columns = f['DATA'].read_all()
>>> print(all_columns)
OrderedDict([('signal', array([   0., 1. ....])), 'flag', array([1, 1, ....])])

Writing

>>> from collections import OrderedDict
>>> f = pycfitsio.create('file.fits')

3 options to write HDUs:

1. list of (name, array) tuples

   >>> f.write_HDU('HDUNAME',
           [('firstcolname', np.arange(10)), ('seccolname', np.arange(10)**2)]
         )
   

2. OrderedDict keys = name values = array

   >>> data = OrderedDict()
   >>> data['firstcolname'] = np.arange(10)
   >>> data['seccolname'] = np.arange(10)**2
   >>> f.write_HDU('HDUNAME', data)
   

3. Compound numpy array

   >>> data = np.ones(10, dtype = [('firstcolname', np.long), ('seccolname', np.double)])
   >>> f.write_HDU('HDUNAME', data)
   

   >>> f.close()