LSST Applications g042eb84c57+730a74494b,g04e9c324dd+8c5ae1fdc5,g134cb467dc+1f1e3e7524,g199a45376c+0ba108daf9,g1fd858c14a+fa7d31856b,g210f2d0738+f66ac109ec,g262e1987ae+83a3acc0e5,g29ae962dfc+d856a2cb1f,g2cef7863aa+aef1011c0b,g35bb328faa+8c5ae1fdc5,g3fd5ace14f+a1e0c9f713,g47891489e3+0d594cb711,g4d44eb3520+c57ec8f3ed,g4d7b6aa1c5+f66ac109ec,g53246c7159+8c5ae1fdc5,g56a1a4eaf3+fd7ad03fde,g64539dfbff+f66ac109ec,g67b6fd64d1+0d594cb711,g67fd3c3899+f66ac109ec,g6985122a63+0d594cb711,g74acd417e5+3098891321,g786e29fd12+668abc6043,g81db2e9a8d+98e2ab9f28,g87389fa792+8856018cbb,g89139ef638+0d594cb711,g8d7436a09f+80fda9ce03,g8ea07a8fe4+760ca7c3fc,g90f42f885a+033b1d468d,g97be763408+a8a29bda4b,g99822b682c+e3ec3c61f9,g9d5c6a246b+0d5dac0c3d,ga41d0fce20+9243b26dd2,gbf99507273+8c5ae1fdc5,gd7ef33dd92+0d594cb711,gdab6d2f7ff+3098891321,ge410e46f29+0d594cb711,geaed405ab2+c4bbc419c6,gf9a733ac38+8c5ae1fdc5,w.2025.38
LSST Data Management Base Package
Loading...
Searching...
No Matches
statistic.py
Go to the documentation of this file.
1# This file is part of pipe_tasks.
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__ = ['Statistic', 'Count', 'Median', 'Percentile', 'StandardDeviation', 'SigmaIQR', 'SigmaMAD',
23 'Statistics']
24
25from abc import ABCMeta, abstractmethod
26from astropy.stats import mad_std
27from dataclasses import dataclass
28import numpy as np
29from scipy.stats import iqr
30
31
32class Statistic(metaclass=ABCMeta):
33 """Compute a statistic from a list of values.
34 """
35 # TODO: Make this a property after upgrade to Python 3.9
36 @classmethod
37 @abstractmethod
38 def name(cls):
39 pass
40
41 @abstractmethod
42 def value(self, values):
43 """Return the value of the statistic given a set of values.
44
45 Parameters
46 ----------
47 values : `Collection` [`float`]
48 A set of values to compute the statistic for.
49 Returns
50 -------
51 statistic : `float`
52 The value of the statistic.
53 """
54 pass
55
56
57class Count(Statistic):
58 @classmethod
59 def name(cls):
60 return "count"
61
62 """The median of a set of values."""
63 def value(self, values):
64 return len(values)
65
66
68 @classmethod
69 def name(cls):
70 return "median"
71
72 """The median of a set of values."""
73 def value(self, values):
74 return np.median(values)
75
76
77@dataclass(frozen=True)
79 """An arbitrary percentile.
80
81 Parameters
82 ----------
83 percentile : `float`
84 A valid percentile (0 <= p <= 100).
85 """
86 percentile: float
87
88 @classmethod
89 def name(cls):
90 return "percentile"
91
92 def value(self, values):
93 return np.percentile(values, self.percentile)
94
95
97 """The standard deviation (sigma)."""
98 @classmethod
99 def name(cls):
100 return "std"
101
102 def value(self, values):
103 return np.std(values)
104
105
107 """The re-scaled inter-quartile range (sigma equivalent)."""
108 @classmethod
109 def name(cls):
110 return "sigma_iqr"
111
112 def value(self, values):
113 return iqr(values, scale='normal')
114
115
117 """The re-scaled median absolute deviation (sigma equivalent)."""
118 @classmethod
119 def name(cls):
120 return "sigma_mad"
121
122 def value(self, values):
123 return mad_std(values)
124
125
126Statistics = {
127 stat.name(): stat
128 for stat in (Count, Median, Percentile, StandardDeviation, SigmaIQR, SigmaMAD)
129}