> >> Point-form functionals (i.e., objective functions that are not integrated >> over time, but just sampled at a given time) drive the initialization of >> the adjoint variables, and they are not supported explicitly in Hong's >> code. S: TSSetObjective() >> > > Should these just be handled by a particular quadrature in the cost > integral, and by this I mean functionals are specified by quadratures. >
Yes, they are evaluated separately in the forward run, see https://bitbucket.org/petsc/petsc/src/c2e9112e7fdfd89985f9ffc4d68b0d46cf7cad52/src/ts/interface/tspdeconstrainedutils.c?at=stefano_zampini%2Ffeature-continuousadjoint&fileviewer=file-view-default#tspdeconstrainedutils.c-420 https://bitbucket.org/petsc/petsc/src/c2e9112e7fdfd89985f9ffc4d68b0d46cf7cad52/src/ts/interface/tspdeconstrainedutils.c?at=stefano_zampini%2Ffeature-continuousadjoint&fileviewer=file-view-default#tspdeconstrainedutils.c-486 https://bitbucket.org/petsc/petsc/src/c2e9112e7fdfd89985f9ffc4d68b0d46cf7cad52/src/ts/interface/tspdeconstrainedutils.c?at=stefano_zampini%2Ffeature-continuousadjoint&fileviewer=file-view-default#tspdeconstrainedutils.c-539 https://bitbucket.org/petsc/petsc/src/c2e9112e7fdfd89985f9ffc4d68b0d46cf7cad52/src/ts/interface/tspdeconstrainedutils.c?at=stefano_zampini%2Ffeature-continuousadjoint&fileviewer=file-view-default#tspdeconstrainedutils.c-549 but their gradient wrt the state variables (for first-order adjoints) dictates the initialization of the adjoint variables. More complicated formulas for semi-explicit index-1 DAEs and second order adjoints (needed by the Hessian matvec) https://bitbucket.org/petsc/petsc/src/c2e9112e7fdfd89985f9ffc4d68b0d46cf7cad52/src/ts/interface/tsadjointts.c?at=stefano_zampini%2Ffeature-continuousadjoint&fileviewer=file-view-default#tsadjointts.c-700 https://bitbucket.org/petsc/petsc/src/c2e9112e7fdfd89985f9ffc4d68b0d46cf7cad52/src/ts/interface/tsadjointts.c?at=stefano_zampini%2Ffeature-continuousadjoint&fileviewer=file-view-default#tsadjointts.c-376 > > For people like me who do not have all the terminology down, is the > Tangent Linear Model (TLM) just the forward sensitivities? > Yes. See the man page for TLMTS for the Tangent linear model ODE. https://bitbucket.org/petsc/petsc/src/c2e9112e7fdfd89985f9ffc4d68b0d46cf7cad52/src/ts/interface/tstlmts.c?at=stefano_zampini%2Ffeature-continuousadjoint&fileviewer=file-view-default#tstlmts.c-403 > >> >> 2017-10-15 18:14 GMT+03:00 Matthew Knepley <[email protected]>: >> >>> Someone had to do it. >>> >>> I will not try to frame the entire discussion. Barry has already thrown >>> down the "show me your interface" gauntlet. However, I want to emphasize >>> one point that may have been lost in the prior discussion. Every example I >>> have looked at so far is focused on the reduced space formulation of the >>> optimization problem. However, I am interested in the full space >>> formulation so that I can do multigrid on the entire optimal control >>> problem. This is not a new idea, in particular Borzi does this in SIAM >>> Review in 2009. I think we have a tremendous opportunity here since other >>> codes cannot do this, it has the potential (I think) for much better >>> globalization, and perhaps can be faster. >>> >>> So, when we come up with interface proposals, I think we should keep a >>> full space solution method in mind. >>> >>> Thanks, >>> >>> Matt >>> >>> -- >>> What most experimenters take for granted before they begin their >>> experiments is infinitely more interesting than any results to which their >>> experiments lead. >>> -- Norbert Wiener >>> >>> https://www.cse.buffalo.edu/~knepley/ <http://www.caam.rice.edu/~mk51/> >>> >> >> >> >> -- >> Stefano >> > > > > -- > What most experimenters take for granted before they begin their > experiments is infinitely more interesting than any results to which their > experiments lead. > -- Norbert Wiener > > https://www.cse.buffalo.edu/~knepley/ <http://www.caam.rice.edu/~mk51/> > -- Stefano
