2 Copyright (C) 2008-2023 EDF R&D
4 This file is part of SALOME ADAO module.
6 This library is free software; you can redistribute it and/or
7 modify it under the terms of the GNU Lesser General Public
8 License as published by the Free Software Foundation; either
9 version 2.1 of the License, or (at your option) any later version.
11 This library is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 Lesser General Public License for more details.
16 You should have received a copy of the GNU Lesser General Public
17 License along with this library; if not, write to the Free Software
18 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
20 See http://www.salome-platform.org/ or email : webmaster.salome@opencascade.com
22 Author: Jean-Philippe Argaud, jean-philippe.argaud@edf.fr, EDF R&D
24 .. index:: single: LinearLeastSquares
25 .. _section_ref_algorithm_LinearLeastSquares:
27 Calculation algorithm "*LinearLeastSquares*"
28 --------------------------------------------
30 .. ------------------------------------ ..
31 .. include:: snippets/Header2Algo01.rst
33 This algorithm realizes a "Least Squares" linear type estimation of the state of
34 a system. It is similar to a :ref:`section_ref_algorithm_Blue`, without its
37 This algorithm is always the fastest of all the optimization algorithms of
38 ADAO. It is theoretically reserved for observation operator cases which are
39 explicitly linear, even if it sometimes works in "slightly" non-linear cases.
40 One can verify the linearity of the observation operator with the help of a
41 :ref:`section_ref_algorithm_LinearityTest`.
43 This algorithm is naturally written for a single estimate, without any dynamic
44 or iterative notion (there is no need in this case for an incremental evolution
45 operator, nor for an evolution error covariance). In ADAO, it can also be used
46 on a succession of observations, placing the estimate in a recursive framework
47 partly similar to a Kalman Filter. A standard estimate is made at each
48 observation step on the state predicted by the incremental evolution model.
50 In all cases, it is recommanded to prefer at least a
51 :ref:`section_ref_algorithm_Blue`, or a
52 :ref:`section_ref_algorithm_ExtendedBlue` or a
53 :ref:`section_ref_algorithm_3DVAR`.
55 .. ------------------------------------ ..
56 .. include:: snippets/Header2Algo02.rst
58 .. include:: snippets/Observation.rst
60 .. include:: snippets/ObservationError.rst
62 .. include:: snippets/ObservationOperator.rst
64 .. ------------------------------------ ..
65 .. include:: snippets/Header2Algo03AdOp.rst
67 .. include:: snippets/EstimationOf_Parameters.rst
69 StoreSupplementaryCalculations
70 .. index:: single: StoreSupplementaryCalculations
72 *List of names*. This list indicates the names of the supplementary
73 variables, that can be available during or at the end of the algorithm, if
74 they are initially required by the user. Their avalability involves,
75 potentially, costly calculations or memory consumptions. The default is then
76 a void list, none of these variables being calculated and stored by default
77 (excepted the unconditionnal variables). The possible names are in the
78 following list (the detailed description of each named variable is given in
79 the following part of this specific algorithmic documentation, in the
80 sub-section "*Information and variables available at the end of the
84 "CostFunctionJAtCurrentOptimum",
86 "CostFunctionJbAtCurrentOptimum",
88 "CostFunctionJoAtCurrentOptimum",
93 "InnovationAtCurrentAnalysis",
95 "SimulatedObservationAtCurrentOptimum",
96 "SimulatedObservationAtCurrentState",
97 "SimulatedObservationAtOptimum",
101 ``{"StoreSupplementaryCalculations":["CurrentState", "Residu"]}``
103 *Tips for this algorithm:*
105 As the *"Background"* and *"BackgroundError"* commands are required for ALL
106 the calculation algorithms in the interface, you have to provide a value,
107 even if these commands are not required for this algorithm, and will not be
108 used. The simplest way is to give "1" as a STRING for both.
110 .. ------------------------------------ ..
111 .. include:: snippets/Header2Algo04.rst
113 .. include:: snippets/Analysis.rst
115 .. include:: snippets/CostFunctionJ.rst
117 .. include:: snippets/CostFunctionJb.rst
119 .. include:: snippets/CostFunctionJo.rst
121 .. ------------------------------------ ..
122 .. include:: snippets/Header2Algo05.rst
124 .. include:: snippets/Analysis.rst
126 .. include:: snippets/CostFunctionJ.rst
128 .. include:: snippets/CostFunctionJAtCurrentOptimum.rst
130 .. include:: snippets/CostFunctionJb.rst
132 .. include:: snippets/CostFunctionJbAtCurrentOptimum.rst
134 .. include:: snippets/CostFunctionJo.rst
136 .. include:: snippets/CostFunctionJoAtCurrentOptimum.rst
138 .. include:: snippets/CurrentOptimum.rst
140 .. include:: snippets/CurrentState.rst
142 .. include:: snippets/CurrentStepNumber.rst
144 .. include:: snippets/ForecastState.rst
146 .. include:: snippets/InnovationAtCurrentAnalysis.rst
148 .. include:: snippets/OMA.rst
150 .. include:: snippets/SimulatedObservationAtCurrentOptimum.rst
152 .. include:: snippets/SimulatedObservationAtCurrentState.rst
154 .. include:: snippets/SimulatedObservationAtOptimum.rst
156 .. ------------------------------------ ..
157 .. _section_ref_algorithm_LinearLeastSquares_examples:
159 .. include:: snippets/Header2Algo06.rst
161 - :ref:`section_ref_algorithm_Blue`
162 - :ref:`section_ref_algorithm_ExtendedBlue`
163 - :ref:`section_ref_algorithm_3DVAR`
164 - :ref:`section_ref_algorithm_LinearityTest`