Merge c726e97 into b56a56a

gammapy/datasets/catalogs.py

@@ -4,14 +4,17 @@
 
 from __future__ import (absolute_import, division, print_function,
                         unicode_literals)
-from astropy.table import Table
+import numpy as np
+from astropy.utils.data import download_file
+from astropy.coordinates import Angle
+from astropy.table import Table, Column
 from ..datasets import get_path
 
 __all__ = ['load_catalog_atnf',
            'load_catalog_hess_galactic',
            # 'load_catalog_hgps',
            'load_catalog_green',
-           # 'load_catalog_snrcat',
+           'load_catalog_snrcat',
            'load_catalog_tevcat',
            ]
 
@@ -116,25 +119,59 @@ def load_catalog_tevcat():
     filename = get_path('catalogs/tevcat.fits.gz', location='remote')
     return Table.read(filename)
 
-# TODO: implement properly
-def load_catalog_snrcat():
+
+def load_catalog_snrcat(cache=True):
     """Load SNRcat supernova remnant catalog.
 
     `SNRcat <http://www.physics.umanitoba.ca/snr/SNRcat/>`__
     is a census of high-energy observations of Galactic supernova remnants.
 
-    Unfortunately the SNRCat information is not available in electronic format.
+    This function obtains the CSV table from
+    http://www.physics.umanitoba.ca/snr/SNRcat/SNRdownload.php?table=SNR
+    and adds some useful columns.
+
+    Note that this only represents a subset of the information available in SNRCat,
+    to get at the rest (e.g. observations and papers) we would have to scrape their
+    web pages.
 
-    This is a dump of http://www.physics.umanitoba.ca/snr/SNRcat/SNRlist.php?textonly from 2015-02-08.
-    It doesn't contain position and extension columns and is really a HTML page with lots of hidden stuff that
-    would have to be scraped, i.e. we can't be simply ``requests.get`` the latest version from there ... sigh.
-    I've contacted them and they might provide a useful version of their catalog in the future ...
+    Parameters
+    ----------
+    cache : bool, optional
+        Whether to use the cache
 
     Returns
     -------
     catalog : `~astropy.table.Table`
         Source catalog
     """
-    filename = get_path('catalogs/SNRCat.csv', location='remote')
-    return Table.read(filename, format='ascii.csv')
+    url = 'http://www.physics.umanitoba.ca/snr/SNRcat/SNRdownload.php?table=SNR'
+    filename = download_file(url, cache=cache)
+
+    # Note: currently the first line contains this comment, which we skip via `header_start=1`
+    # This file was downloaded on 2015-05-11T03:00:55 CDT from http://www.physics.umanitoba.ca/snr/SNRcat
+    table = Table.read(filename, format='ascii.csv', header_start=1, delimiter=';')
+
+    # Fix the columns to have common column names and add unit info
+    table.rename_column('G', 'Source_Name')
+    table.rename_column('G_lon', 'GLON')
+    table['GLON'].unit = 'deg'
+    table.rename_column('G_lat', 'GLAT')
+    table['GLAT'].unit = 'deg'
+    table.rename_column('J', 'Source_JName')
+
+    ra = Angle(table['J_ra'], unit='hour').deg
+    dec = Angle(table['J_dec'], unit='deg').deg
+    index = table.index_column('J_dec') + 1
+    table.add_column(Column(ra, name='RAJ2000', unit='deg'), index=index)
+    table.add_column(Column(dec, name='DEJ2000', unit='deg'), index=index)
+
+    distance = np.mean([table['distance_min'], table['distance_max']], axis=0)
+    index = table.index_column('distance_max') + 1
+    table.add_column(Column(distance, name='distance', unit='kpc'), index=index)
+
+    # TODO: make age, distance and size columns quantities with units
+
+    # TODO: parse size_radio and size_X to get float columns
+
+    return table
 

gammapy/datasets/tests/test_catalogs.py

@@ -24,11 +24,11 @@ def test_load_catalog_green():
     assert len(catalog) == 294
 
 
-# TODO: activate test when available
 @remote_data
-def _test_load_catalog_snrcat():
+def test_load_catalog_snrcat():
     catalog = datasets.load_catalog_snrcat()
-    assert len(catalog) == 338
+    assert len(catalog) > 300
+    assert set(['Source_Name', 'RAJ2000']).issubset(catalog.colnames)
 
 
 @remote_data