When an objective function is provided f(w) is the objective function otherwise f(w) = ||F(w)||^2. x is the current step and y is the search direction.
This has no checks on whether the secant method is actually converging.
| -snes_linesearch_max_it <maxit> | - maximum number of iterations, default is 1 | |
| -snes_linesearch_maxstep <length> | - the algorithm insures that a step length is never longer than this value | |
| -snes_linesearch_damping <damping> | - initial step is scaled back by this factor, default is 1.0 | |
| -snes_linesearch_minlambda <minlambda> | - minimum allowable lambda |