5 papers
The Influence of an Adjoint Mismatch on the Primal-Dual Douglas-Rachford Method
Emanuele Naldi, Felix Schneppe
The primal-dual Douglas-Rachford method is a well-known algorithm to solve optimization problems written as convex-concave saddle-point problems. Each iteration involves solving a…
Computing adjoint mismatch of linear maps
Jonas Bresch, Dirk A. Lorenz, Felix Schneppe +1
This paper considers the problem of detecting adjoint mismatch for two linear maps. To clarify, this means that we aim to calculate the operator norm for the difference of two line…
Matrix-free stochastic calculation of operator norms without using adjoints
Jonas Bresch, Dirk A. Lorenz, Felix Schneppe +1
This paper considers the problem of computing the operator norm of a linear map between finite dimensional Hilbert spaces when only evaluations of the linear map are available and…
Linearly convergent adjoint free solution of least squares problems by random descent
Dirk A. Lorenz, Felix Schneppe, Lionel Tondji
We consider the problem of solving linear least squares problems in a framework where only evaluations of the linear map are possible. We derive randomized methods that do not need…
Chambolle-Pock's Primal-Dual Method with Mismatched Adjoint
Dirk A. Lorenz, Felix Schneppe
The primal-dual method of Chambolle and Pock is a widely used algorithm to solve various optimization problems written as convex-concave saddle point problems. Each update step inv…