Franchois, "A subspace preconditioned LSQR Gauss-Newton method with a constrained
linesearch path applied to 3D biomedical microwave imaging," Int.
We follow Scheinberg and Tang [30] and implement a limited-memory BFGS (L-BFGS) variant of the proximal-gradient method that has no linesearch and that approximately evaluates the proximal operator.
This modification takes the place of a potentially expensive linesearch, and the correction is increased at each iteration if a certain condition for decrease is not satisfied.
[27] --, A globally convergent version of mma without
linesearch, in Proceedings of the First World Congress of Structural and Multidisciplinary Optimization, N.
Here, a quadratic
linesearch technique [8] is employed to determine the step length [[lambda].sup.(k)], with a = [10.sup.-4], [[lambda].sub.min] = 1/10 and [[lambda].sub.max] = 1/2.