|  | // Ceres Solver - A fast non-linear least squares minimizer | 
|  | // Copyright 2018 Google Inc. All rights reserved. | 
|  | // http://ceres-solver.org/ | 
|  | // | 
|  | // Redistribution and use in source and binary forms, with or without | 
|  | // modification, are permitted provided that the following conditions are met: | 
|  | // | 
|  | // * Redistributions of source code must retain the above copyright notice, | 
|  | //   this list of conditions and the following disclaimer. | 
|  | // * Redistributions in binary form must reproduce the above copyright notice, | 
|  | //   this list of conditions and the following disclaimer in the documentation | 
|  | //   and/or other materials provided with the distribution. | 
|  | // * Neither the name of Google Inc. nor the names of its contributors may be | 
|  | //   used to endorse or promote products derived from this software without | 
|  | //   specific prior written permission. | 
|  | // | 
|  | // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" | 
|  | // AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE | 
|  | // IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE | 
|  | // ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE | 
|  | // LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR | 
|  | // CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF | 
|  | // SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS | 
|  | // INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN | 
|  | // CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) | 
|  | // ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE | 
|  | // POSSIBILITY OF SUCH DAMAGE. | 
|  | // | 
|  | // Authors: sameeragarwal@google.com (Sameer Agarwal) | 
|  |  | 
|  | #include <memory> | 
|  |  | 
|  | #include "benchmark/benchmark.h" | 
|  | #include "ceres/ceres.h" | 
|  | #include "ceres/jet.h" | 
|  |  | 
|  | namespace ceres { | 
|  |  | 
|  | // From the NIST problem collection. | 
|  | struct Rat43CostFunctor { | 
|  | Rat43CostFunctor(const double x, const double y) : x_(x), y_(y) {} | 
|  |  | 
|  | template <typename T> | 
|  | bool operator()(const T* parameters, T* residuals) const { | 
|  | const T& b1 = parameters[0]; | 
|  | const T& b2 = parameters[1]; | 
|  | const T& b3 = parameters[2]; | 
|  | const T& b4 = parameters[3]; | 
|  | residuals[0] = b1 * pow(1.0 + exp(b2 - b3 * x_), -1.0 / b4) - y_; | 
|  | return true; | 
|  | } | 
|  |  | 
|  | private: | 
|  | const double x_; | 
|  | const double y_; | 
|  | }; | 
|  |  | 
|  | // Simple implementation of autodiff using Jets directly instead of | 
|  | // going through the machinery of AutoDiffCostFunction, which does | 
|  | // the same thing, but much more generically. | 
|  | class Rat43Automatic : public ceres::SizedCostFunction<1, 4> { | 
|  | public: | 
|  | Rat43Automatic(const Rat43CostFunctor* functor) : functor_(functor) {} | 
|  | virtual ~Rat43Automatic() {} | 
|  | bool Evaluate(double const* const* parameters, | 
|  | double* residuals, | 
|  | double** jacobians) const final { | 
|  | if (!jacobians) { | 
|  | return (*functor_)(parameters[0], residuals); | 
|  | } | 
|  |  | 
|  | typedef ceres::Jet<double, 4> JetT; | 
|  | JetT jets[4]; | 
|  | for (int i = 0; i < 4; ++i) { | 
|  | jets[i].a = parameters[0][i]; | 
|  | jets[i].v.setZero(); | 
|  | jets[i].v[i] = 1.0; | 
|  | } | 
|  |  | 
|  | JetT result; | 
|  | (*functor_)(jets, &result); | 
|  |  | 
|  | residuals[0] = result.a; | 
|  | for (int i = 0; i < 4; ++i) { | 
|  | jacobians[0][i] = result.v[i]; | 
|  | } | 
|  | return true; | 
|  | } | 
|  |  | 
|  | private: | 
|  | std::unique_ptr<const Rat43CostFunctor> functor_; | 
|  | }; | 
|  |  | 
|  | static void BM_Rat43AutoDiff(benchmark::State& state) { | 
|  | double parameter_block1[] = {1., 2., 3., 4.}; | 
|  | double* parameters[] = {parameter_block1}; | 
|  |  | 
|  | double jacobian1[] = {0.0, 0.0, 0.0, 0.0}; | 
|  | double residuals; | 
|  | double* jacobians[] = {jacobian1}; | 
|  | const double x = 0.2; | 
|  | const double y = 0.3; | 
|  | std::unique_ptr<ceres::CostFunction> cost_function( | 
|  | new ceres::AutoDiffCostFunction<Rat43CostFunctor, 1, 4>( | 
|  | new Rat43CostFunctor(x, y))); | 
|  |  | 
|  | while (state.KeepRunning()) { | 
|  | cost_function->Evaluate( | 
|  | parameters, &residuals, state.range(0) ? jacobians : nullptr); | 
|  | } | 
|  | } | 
|  | BENCHMARK(BM_Rat43AutoDiff)->Arg(0)->Arg(1); | 
|  |  | 
|  | }  // namespace ceres | 
|  |  | 
|  | BENCHMARK_MAIN(); |