LSST Applications  21.0.0-147-g0e635eb1+1acddb5be5,22.0.0+052faf71bd,22.0.0+1ea9a8b2b2,22.0.0+6312710a6c,22.0.0+729191ecac,22.0.0+7589c3a021,22.0.0+9f079a9461,22.0.1-1-g7d6de66+b8044ec9de,22.0.1-1-g87000a6+536b1ee016,22.0.1-1-g8e32f31+6312710a6c,22.0.1-10-gd060f87+016f7cdc03,22.0.1-12-g9c3108e+df145f6f68,22.0.1-16-g314fa6d+c825727ab8,22.0.1-19-g93a5c75+d23f2fb6d8,22.0.1-19-gb93eaa13+aab3ef7709,22.0.1-2-g8ef0a89+b8044ec9de,22.0.1-2-g92698f7+9f079a9461,22.0.1-2-ga9b0f51+052faf71bd,22.0.1-2-gac51dbf+052faf71bd,22.0.1-2-gb66926d+6312710a6c,22.0.1-2-gcb770ba+09e3807989,22.0.1-20-g32debb5+b8044ec9de,22.0.1-23-gc2439a9a+fb0756638e,22.0.1-3-g496fd5d+09117f784f,22.0.1-3-g59f966b+1e6ba2c031,22.0.1-3-g849a1b8+f8b568069f,22.0.1-3-gaaec9c0+c5c846a8b1,22.0.1-32-g5ddfab5d3+60ce4897b0,22.0.1-4-g037fbe1+64e601228d,22.0.1-4-g8623105+b8044ec9de,22.0.1-5-g096abc9+d18c45d440,22.0.1-5-g15c806e+57f5c03693,22.0.1-7-gba73697+57f5c03693,master-g6e05de7fdc+c1283a92b8,master-g72cdda8301+729191ecac,w.2021.39
LSST Data Management Base Package
denormalizeMatches.py
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1 # This file is part of meas_astrom.
2 #
3 # Developed for the LSST Data Management System.
4 # This product includes software developed by the LSST Project
5 # (https://www.lsst.org).
6 # See the COPYRIGHT file at the top-level directory of this distribution
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21 
22 __all__ = ["denormalizeMatches"]
23 
24 import lsst.afw.table as afwTable
25 
26 
27 def denormalizeMatches(matches, matchMeta=None):
28  """Generate a denormalized Catalog of matches
29 
30  Parameters
31  ----------
32  matches : `list` of `lsst.afw.table.ReferenceMatch`
33  List of matches between reference catalog and source catalog.
34  matchMeta : `lsst.daf.base.PropertyList`
35  Matching metadata to write in catalog.
36 
37  Returns
38  -------
39  catalog : `lsst.afw.table.BaseCatalog`
40  Catalog containing matchlist entries.
41 
42  Notes
43  -----
44  This is intended for writing matches in a convenient way.
45  Normally we write matches in a 'normalized' form: recording only the join
46  table (reference ID, source ID) to minimise space (the reference and source
47  catalogs should both be available separately, so the only extra information
48  we need is how to join them). However, using that can be a pain, since it
49  requires reading each catalog and doing the join.
50 
51  This function generates a Catalog containing all the information in the
52  matches. The reference catalog entries are in columns with 'ref'
53  prepended, while the source catalog entries are in columns with 'src'
54  prepended (including any alias mappings). The distance between the
55  matches is in a column named "distance".
56 
57  See Also
58  --------
59  lsst.afw.table.packMatches
60  """
61  # TODO: DM-16863 Current this link is removed due to the conversion of
62  # afw.table not yet being complete and causing an error on build.
63  # """
64  if len(matches) == 0:
65  raise RuntimeError("No matches provided.")
66 
67  refSchema = matches[0].first.getSchema()
68  srcSchema = matches[0].second.getSchema()
69 
70  refMapper, srcMapper = afwTable.SchemaMapper.join([refSchema, srcSchema], ["ref_", "src_"])
71  schema = refMapper.editOutputSchema()
72 
73  schema = afwTable.catalogMatches.copyAliasMapWithPrefix(srcSchema, schema, prefix="src_")
74  schema = afwTable.catalogMatches.copyAliasMapWithPrefix(refSchema, schema, prefix="ref_")
75 
76  distKey = schema.addField("distance", type=float, doc="Distance between ref and src")
77 
78  catalog = afwTable.BaseCatalog(schema)
79  catalog.reserve(len(matches))
80  for mm in matches:
81  row = catalog.addNew()
82  row.assign(mm.first, refMapper)
83  row.assign(mm.second, srcMapper)
84  row.set(distKey, mm.distance)
85 
86  if matchMeta is not None:
87  catalog.getTable().setMetadata(matchMeta)
88 
89  return catalog
def denormalizeMatches(matches, matchMeta=None)