Line data    Source code

       1           0 : // Distributed under the MIT License.
       2             : // See LICENSE.txt for details.
       3             : 
       4             : #pragma once
       5             : 
       6             : #error "RootFinding/NewtonRaphson.hpp does not provide any functionality."
       7             : 
       8             : namespace RootFinder {
       9             : /*!
      10             :  * \ingroup NumericalAlgorithmsGroup
      11             :  * For the nonlinear solver, see NonlinearSolver::newton_raphson.  We
      12             :  * do not provide a Newton-Raphson root finder.  The Boost
      13             :  * implementation is buggy and can return the wrong answer, and it is
      14             :  * not clear that performance would be better than RootFinder::toms748
      15             :  * in practice.
      16             :  *
      17             :  * Newton-Raphson is asymptotically faster than TOMS748 in the ideal
      18             :  * case, but that assumes that function evaluations take the same
      19             :  * amount of time for both solvers, while in reality the derivatives
      20             :  * are often as or even more expensive than the values.  Additionally,
      21             :  * for realistic problems, convergence is usually fast enough that
      22             :  * neither solver reaches the asymptotic regime.  Newton-Raphson also
      23             :  * has the advantage of requiring less work internally in the solver
      24             :  * implementation, but, again, for realistic problems solver overhead
      25             :  * is usually dwarfed by the function evaluations.
      26             :  */
      27           1 : void newton_raphson() = delete;
      28             : }  // namespace RootFinder