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WorkingGroups/TAM/ReferenceManual/NemoTamBasics (diff) – NEMO

Changes between Version 5 and Version 6 of WorkingGroups/TAM/ReferenceManual/NemoTamBasics


Ignore:
Timestamp:
2010-06-01T18:13:57+02:00 (14 years ago)
Author:
cdlod
Comment:

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  • WorkingGroups/TAM/ReferenceManual/NemoTamBasics

    v5 v6  
    1 = TAM what for ? = 
     1= Tangent and adjoint models (TAM) = 
     2 
     3== TAM what for ? == 
     4 
    25The development of tangent and adjoint models is 
    36an important step in addressing sensitivity analysis and variational 
     
    1114cost function around a background control. 
    1215 
    13 = Tangent and Adjoint coding principle =  
     16== Tangent and Adjoint coding principle == 
    1417the original program {{{P}}}, whatever its size and run time, computes a function ''F'', ''X''∈ IR^''m''^ → ''Y'' ∈ IR^''n''^ which is the composition of the elementary functions computed by each run-time instruction. In other words if {{{P}}} executes a sequence of elementary statements ''I,,k,,,k'' ∈ [1..''p''], then {{{P}}} actually evaluates 
    1518 
     
    4144for specific details about practical adjoint coding refer to Giering and Kaminski (1998)  
    4245 
    43 = Potential issues =  
     46== Potential issues == 
    4447 
    4548 * the major approximations : non differentiability issues, simplification of the direct model before linearization,  validity of the tangent linear hypothesis over some time window, etc.