LSST Applications  21.0.0-129-gdb38469a+1bd5e57dbb,22.0.0+03706a241d,22.0.0+11a2aa21cd,22.0.0+304ef9150d,22.0.0+64c1bc5aa5,22.0.0+738e4e628a,22.0.0+7b3a3f865e,22.0.0+e6cbeb5e1c,22.0.0+f4f536df4c,22.0.0+fbee83b840,22.0.1-1-g1b65d06+da7944893b,22.0.1-1-g7058be7+1cf78af69b,22.0.1-1-g7dab645+3cb5b2fc85,22.0.1-1-g8760c09+64c1bc5aa5,22.0.1-1-g949febb+64c1bc5aa5,22.0.1-1-ga324b9c+304ef9150d,22.0.1-1-ga86695c+e6cbeb5e1c,22.0.1-1-gf9d8b05+03706a241d,22.0.1-10-g781e53d+24107c5c9a,22.0.1-10-gba590ab+767afa1eb6,22.0.1-13-g00a9d746+853a472d02,22.0.1-13-g76f9b8d+e6cbeb5e1c,22.0.1-16-g996ca242+58f6652caa,22.0.1-18-gb17765a+d8291b220b,22.0.1-2-gcb770ba+2dea998090,22.0.1-22-gf1d71818e+4206820b0d,22.0.1-3-g7aa11f2+e6cbeb5e1c,22.0.1-3-g8c1d971+f253ffa91f,22.0.1-3-g997b569+1088d310ed,22.0.1-4-g1930a60+6871d0c7f6,22.0.1-4-g5b7b756+6b209d634c,22.0.1-6-ga02864e+6871d0c7f6,22.0.1-7-g3402376+e9d2d9bd2c,22.0.1-7-g65f59fa+ece367c4df,master-gcc5351303a+f4f536df4c,w.2021.31
LSST Data Management Base Package
_source.py
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1 # This file is part of afw.
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
7 # for details of code ownership.
8 #
9 # This program is free software: you can redistribute it and/or modify
10 # it under the terms of the GNU General Public License as published by
11 # the Free Software Foundation, either version 3 of the License, or
12 # (at your option) any later version.
13 #
14 # This program is distributed in the hope that it will be useful,
15 # but WITHOUT ANY WARRANTY; without even the implied warranty of
16 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 # GNU General Public License for more details.
18 #
19 # You should have received a copy of the GNU General Public License
20 # along with this program. If not, see <https://www.gnu.org/licenses/>.
21 
22 __all__ = []
23 
24 from lsst.utils import continueClass
25 from ._base import Catalog
26 from ._table import SourceCatalog, SourceTable
27 
28 Catalog.register("Source", SourceCatalog)
29 
30 
31 @continueClass
33 
34  def getChildren(self, parent, *args):
35  """Return the subset of self for which the parent field equals the
36  given value.
37 
38  In order for this method to return the correct result, it must be
39  sorted by parent (i.e. self.isSorted(SourceTable.getParentKey()) must
40  be True). This is naturally the case with SourceCatalogs produced by
41  the detection and deblending tasks, but it may not be true when
42  concatenating multiple such catalogs.
43 
44  Additional Catalogs or sequences whose elements correspond in order to
45  the records of self (i.e. ``zip(self, *args)`` is valid) will be
46  subset using the same slice object used on self, and these subsets
47  will be returned along with the subset of self.
48 
49  Parameters
50  ----------
51  parent : `int` or `iterable` of `int`
52  ID(s) of the parent(s) to get children for.
53  args : `~lsst.afw.table.Catalog`
54  Additional catalogs to subset for the children to return.
55 
56  Returns
57  -------
58  children : a single iterable of `~lsst.afw.table.SourceRecord`
59  Children sources if ``parent`` is of type `int`, or a generator
60  yielding a `~lsst.afw.table.SourceRecord`s Children sources for
61  each parent if ``parent`` is an `iterable`.
62 
63  Raises
64  ------
65  AssertionError
66  Raised if the catalog is not sorted by the parent key.
67 
68  Notes
69  -----
70  Each call to this function checks if the catalog is sorted, which is
71  of O(n) complexity, while fetching the children is of O(log n). To
72  minimize the computational overhead, it is preferable to prepare an
73  iterable of parent ids for which the children need to be fetched and
74  pass the iterable as ``parent``.
75  """
76  if not self.isSorted(SourceTable.getParentKey()):
77  raise AssertionError(
78  "The table is not sorted by parent, so cannot getChildren")
79 
80  def _getChildrenWithoutChecking(parent):
81  """Return the subset of self for which the parent field equals the
82  given value.
83 
84  This function works as desired only if `self` is sorted by the
85  parent key, but does not check if it is sorted. This function must
86  be used only after ensuring outside of the function that
87  self.isSorted(SourceTable.getParentKey() evaluates to True.
88 
89  Parameter
90  ---------
91  parent : `int`
92  ID of the parent to get children for.
93 
94  Returns
95  -------
96  children : iterable of `~lsst.afw.table.SourceRecord`
97  Children sources.
98  """
99  s = self.equal_range(parent, SourceTable.getParentKey())
100  if args:
101  return (self[s],) + tuple(arg[s] for arg in args)
102  else:
103  return self[s]
104 
105  try:
106  return (_getChildrenWithoutChecking(p) for p in parent)
107  except TypeError:
108  return _getChildrenWithoutChecking(parent)
def getChildren(self, parent, *args)
Definition: _source.py:34