.. only:: html
.. note::
:class: sphx-glr-download-link-note
Click :ref:`here ` to download the full example code
.. rst-class:: sphx-glr-example-title
.. _sphx_glr_generated_examples_io_create-mef.py:
=====================================================
Create a multi-extension FITS (MEF) file from scratch
=====================================================
This example demonstrates how to create a multi-extension FITS (MEF)
file from scratch using `astropy.io.fits`.
*By: Erik Bray*
*License: BSD*
.. code-block:: default
import os
HDUList objects are used to hold all the HDUs in a FITS file. This
``HDUList`` class is a subclass of Python's builtin `list`. and can be
created from scratch. For example, to create a FITS file with
three extensions:
.. code-block:: default
from astropy.io import fits
new_hdul = fits.HDUList()
new_hdul.append(fits.ImageHDU())
new_hdul.append(fits.ImageHDU())
Write out the new file to disk:
.. code-block:: default
new_hdul.writeto('test.fits')
Alternatively, the HDU instances can be created first (or read from an
existing FITS file).
Create a multi-extension FITS file with two empty IMAGE extensions (a
default PRIMARY HDU is prepended automatically if one is not specified;
we use ``overwrite=True`` to overwrite the file if it already exists):
.. code-block:: default
hdu1 = fits.PrimaryHDU()
hdu2 = fits.ImageHDU()
new_hdul = fits.HDUList([hdu1, hdu2])
new_hdul.writeto('test.fits', overwrite=True)
Finally, we'll remove the file we created:
.. code-block:: default
os.remove('test.fits')
.. rst-class:: sphx-glr-timing
**Total running time of the script:** ( 0 minutes 5.967 seconds)
.. _sphx_glr_download_generated_examples_io_create-mef.py:
.. only :: html
.. container:: sphx-glr-footer
:class: sphx-glr-footer-example
.. container:: sphx-glr-download sphx-glr-download-python
:download:`Download Python source code: create-mef.py `
.. container:: sphx-glr-download sphx-glr-download-jupyter
:download:`Download Jupyter notebook: create-mef.ipynb `
.. only:: html
.. rst-class:: sphx-glr-signature
`Gallery generated by Sphinx-Gallery `_