This line search implementation is not a line search at all; it simply uses the full step. Thus, this routine is intended for methods with well-scaled updates; i.e. Newton's method (SNESNEWTONLS), on well-behaved problems.
Options Database Keys
-snes_linesearch_damping (1.0) damping parameter.
- - -snes_linesearch_norms (true) whether to compute norms or not.
Notes
For methods with ill-scaled updates (SNESNRICHARDSON, SNESNCG), a small
damping parameter may yield satisfactory but slow convergence despite
the simplicity of the line search.