.. _WODEN demonstrated via examples:

``WODEN`` demonstrated via examples
=====================================

Below are a number of example simulations with various settings. You can find and run these examples in the ``WODEN/examples`` directory. I'll let you know how much storage you'll need for each set of simulation and images (things can get large with radio data).

Two of the southern hemisphere sky models are largish (a total of about 100 MB), so instead of bundling them into the github, I've added links into the relevant instructions to download them. For the LOFAR examples, the sky models are linked within the notebook, so you can download them from source.

.. note:: For all simulation times reported in the below, when using a GPU, I used an NVIDIA GeForce GTX 1080 Ti with 12 GB of RAM. The CPU used was a AMD Ryzen™ 7 2700X x16.

The examples are:

.. toctree::

   fornaxA_sim
   MWA_EoR1_sim
   eda2_haslam_sim
   dipole_ampflags
   polarisation_examples.ipynb
   lofar_lotss.ipynb
   lofar_lba_ncp.ipynb
   relocate_everybeam_array.ipynb
   hera_sim.ipynb

**Fornax A simulation** - two examples that compare a point/Gaussian model to a shapelet model. This serves as a general introduction on how to simulate an MWA observation using a ``metafits`` file, with a few extra commands. It also serves as a comparison of running with ``woden_float`` and ``woden_double``.

**MWA EoR1 simulation** - demonstrates using a larger (>300,000) source catalogue

**EDA2 Haslam Map simulation** - this demonstrates using ``WODEN`` without a ``metafits`` file, using a text file to describe the array layout, and using the ``EDA2`` beam.

**MWA dipole amplitudes and flags** - this demonstrates using ``WODEN`` when supplying either dipole flags or amplitudes to the MWA FEE beam (via ``hyperbeam``). *Note, currently this only works with the FEE beam, not the analytic MWA beam*

**Polarisation** - demonstrates how to get create polarised sky models, simulate them, and gives examples of how to inspect the results. 

**LOFAR LoTSS DR2 cutout matching** - demonstrates how to get grab a chunk of the LoTSS DR2 gaussian catalogue, convert to ``WODEN`` format, and simulate it with the LOFAR HBA beam.

**LOFAR LBA NCP** - demonstrates how to simulate the LOFAR LBA beam with a sky model of the North Celestial Pole. Also has a cheeky bit of cross-matching, and discusses how borked plotting images at the NCP can be.

**Move LOFAR array to Inyarrimanha Ilgari Bundara (MRO)** - demonstrates how to move a LOFAR measurement set, which is necessary for running the ``EveryBeam`` ``LOFAR`` beam model, to the MRO. Useful if you want to compare two different arrays with the same sky model and observation settings. Included as an example as editing measurement sets is hard but has to be done to change fundamental settings hard-coded into ``EveryBeam``.

**HERA simulations** - demonstrates how to simulate a HERA observation. Makes some beam plots using both the CST text and beam FITS formats used by ``UVBeam``. Runs a simulation of the ``F1`` field (RA=2h, Dec=-30 deg) using the phase 1 array layout configuration.

.. warning:: If you have a GPU with small amounts of RAM (say 2GB) some of these simulations won't work to DOUBLE precision, you won't have enough memory. You can add the ``--precision=float`` argument to switch to a lower memory requirement (for the loss of accuracy).