I checked the results again and can confirm that it is a bug on our side. A merge request has been created to fix it: https://gitlab.com/petsc/petsc/-/merge_requests/2830
Thanks, Hong (Mr.) On Jun 2, 2020, at 6:26 PM, Salazar De Troya, Miguel <[email protected]<mailto:[email protected]>> wrote: Hong, That is not the correct result, however, we can obtain the correct result if we comment ts.setThetaEndpoint(True). Why is it so? Thanks Miguel From: "Zhang, Hong" <[email protected]<mailto:[email protected]>> Date: Tuesday, June 2, 2020 at 3:31 PM To: "Salazar De Troya, Miguel" <[email protected]<mailto:[email protected]>> Cc: "[email protected]<mailto:[email protected]>" <[email protected]<mailto:[email protected]>> Subject: Re: [petsc-users] TSAdjoint not working correctly when using TSThetaSetEndpoint(true) Miguel, After I uncommented ts.setThetaEndpoint(True) and removed ts.setProblemType(False.ProblemType.LINEAR) in your code, I got the following result: hongzhang@Hongs-MacBook-Pro$ python3 petsc_question_2.py Cost function Vec Object: 1 MPI processes type: seq 127.781 Exact value: 127.78112 Numerical sensitivity w.r.t. a 12.778122049945212 Real sensitivity w.r.t a 12.7781121978613 Numerical sensitivity w.r.t. b 83.8907580310942 Real sensitivity w.r.t b 211.67168296791954 -ts_type cn gives the same result. What was the problem you encountered? Thanks, Hong (Mr.) On Jun 2, 2020, at 2:36 PM, Salazar De Troya, Miguel via petsc-users <[email protected]<mailto:[email protected]>> wrote: Hello, I am attaching a simple example that uses TSAdjoint to calculate the sensitivity of a 1 degree of freedom ODE. When using theta methods, it returns the right sensitivity as given by the analytical solution. When I set `ts.setThetaEndpoint(True)`, it does not work. Is there a theoretical reason why? I was using this option because using the options ts.setType(ts.Type.THETA) ts.setTheta(0.5) ts.setThetaEndpoint(True) is equivalent to using ts.Type.CN Thanks Miguel Miguel A. Salazar de Troya Postdoctoral Researcher, Lawrence Livermore National Laboratory B141 Rm: 1085-5 Ph: 1(925) 422-6411 <petsc_question_2.py>
