|  | // Ceres Solver - A fast non-linear least squares minimizer | 
|  | // Copyright 2015 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. | 
|  | // | 
|  | // Author: mierle@gmail.com (Keir Mierle) | 
|  |  | 
|  | #include "ceres/c_api.h" | 
|  |  | 
|  | #include <cmath> | 
|  |  | 
|  | #include "glog/logging.h" | 
|  | #include "gtest/gtest.h" | 
|  |  | 
|  | // Duplicated from curve_fitting.cc. | 
|  | int num_observations = 67; | 
|  | // clang-format off | 
|  | double data[] = { | 
|  | 0.000000e+00, 1.133898e+00, | 
|  | 7.500000e-02, 1.334902e+00, | 
|  | 1.500000e-01, 1.213546e+00, | 
|  | 2.250000e-01, 1.252016e+00, | 
|  | 3.000000e-01, 1.392265e+00, | 
|  | 3.750000e-01, 1.314458e+00, | 
|  | 4.500000e-01, 1.472541e+00, | 
|  | 5.250000e-01, 1.536218e+00, | 
|  | 6.000000e-01, 1.355679e+00, | 
|  | 6.750000e-01, 1.463566e+00, | 
|  | 7.500000e-01, 1.490201e+00, | 
|  | 8.250000e-01, 1.658699e+00, | 
|  | 9.000000e-01, 1.067574e+00, | 
|  | 9.750000e-01, 1.464629e+00, | 
|  | 1.050000e+00, 1.402653e+00, | 
|  | 1.125000e+00, 1.713141e+00, | 
|  | 1.200000e+00, 1.527021e+00, | 
|  | 1.275000e+00, 1.702632e+00, | 
|  | 1.350000e+00, 1.423899e+00, | 
|  | 1.425000e+00, 1.543078e+00, | 
|  | 1.500000e+00, 1.664015e+00, | 
|  | 1.575000e+00, 1.732484e+00, | 
|  | 1.650000e+00, 1.543296e+00, | 
|  | 1.725000e+00, 1.959523e+00, | 
|  | 1.800000e+00, 1.685132e+00, | 
|  | 1.875000e+00, 1.951791e+00, | 
|  | 1.950000e+00, 2.095346e+00, | 
|  | 2.025000e+00, 2.361460e+00, | 
|  | 2.100000e+00, 2.169119e+00, | 
|  | 2.175000e+00, 2.061745e+00, | 
|  | 2.250000e+00, 2.178641e+00, | 
|  | 2.325000e+00, 2.104346e+00, | 
|  | 2.400000e+00, 2.584470e+00, | 
|  | 2.475000e+00, 1.914158e+00, | 
|  | 2.550000e+00, 2.368375e+00, | 
|  | 2.625000e+00, 2.686125e+00, | 
|  | 2.700000e+00, 2.712395e+00, | 
|  | 2.775000e+00, 2.499511e+00, | 
|  | 2.850000e+00, 2.558897e+00, | 
|  | 2.925000e+00, 2.309154e+00, | 
|  | 3.000000e+00, 2.869503e+00, | 
|  | 3.075000e+00, 3.116645e+00, | 
|  | 3.150000e+00, 3.094907e+00, | 
|  | 3.225000e+00, 2.471759e+00, | 
|  | 3.300000e+00, 3.017131e+00, | 
|  | 3.375000e+00, 3.232381e+00, | 
|  | 3.450000e+00, 2.944596e+00, | 
|  | 3.525000e+00, 3.385343e+00, | 
|  | 3.600000e+00, 3.199826e+00, | 
|  | 3.675000e+00, 3.423039e+00, | 
|  | 3.750000e+00, 3.621552e+00, | 
|  | 3.825000e+00, 3.559255e+00, | 
|  | 3.900000e+00, 3.530713e+00, | 
|  | 3.975000e+00, 3.561766e+00, | 
|  | 4.050000e+00, 3.544574e+00, | 
|  | 4.125000e+00, 3.867945e+00, | 
|  | 4.200000e+00, 4.049776e+00, | 
|  | 4.275000e+00, 3.885601e+00, | 
|  | 4.350000e+00, 4.110505e+00, | 
|  | 4.425000e+00, 4.345320e+00, | 
|  | 4.500000e+00, 4.161241e+00, | 
|  | 4.575000e+00, 4.363407e+00, | 
|  | 4.650000e+00, 4.161576e+00, | 
|  | 4.725000e+00, 4.619728e+00, | 
|  | 4.800000e+00, 4.737410e+00, | 
|  | 4.875000e+00, 4.727863e+00, | 
|  | 4.950000e+00, 4.669206e+00, | 
|  | }; | 
|  | // clang-format on | 
|  |  | 
|  | // A test cost function, similar to the one in curve_fitting.c. | 
|  | static int exponential_residual(void* user_data, | 
|  | double** parameters, | 
|  | double* residuals, | 
|  | double** jacobians) { | 
|  | auto* measurement = static_cast<double*>(user_data); | 
|  | double x = measurement[0]; | 
|  | double y = measurement[1]; | 
|  | double m = parameters[0][0]; | 
|  | double c = parameters[1][0]; | 
|  |  | 
|  | residuals[0] = y - exp(m * x + c); | 
|  | if (jacobians == nullptr) { | 
|  | return 1; | 
|  | } | 
|  | if (jacobians[0] != nullptr) { | 
|  | jacobians[0][0] = -x * exp(m * x + c);  // dr/dm | 
|  | } | 
|  | if (jacobians[1] != nullptr) { | 
|  | jacobians[1][0] = -exp(m * x + c);  // dr/dc | 
|  | } | 
|  | return 1; | 
|  | } | 
|  |  | 
|  | namespace ceres { | 
|  | namespace internal { | 
|  |  | 
|  | TEST(C_API, SimpleEndToEndTest) { | 
|  | double m = 0.0; | 
|  | double c = 0.0; | 
|  | double* parameter_pointers[] = {&m, &c}; | 
|  | int parameter_sizes[] = {1, 1}; | 
|  |  | 
|  | ceres_problem_t* problem = ceres_create_problem(); | 
|  | for (int i = 0; i < num_observations; ++i) { | 
|  | ceres_problem_add_residual_block( | 
|  | problem, | 
|  | exponential_residual,  // Cost function | 
|  | &data[2 * i],          // Points to the (x,y) measurement | 
|  | nullptr,               // Loss function | 
|  | nullptr,               // Loss function user data | 
|  | 1,                     // Number of residuals | 
|  | 2,                     // Number of parameter blocks | 
|  | parameter_sizes, | 
|  | parameter_pointers); | 
|  | } | 
|  |  | 
|  | ceres_solve(problem); | 
|  |  | 
|  | EXPECT_NEAR(0.3, m, 0.02); | 
|  | EXPECT_NEAR(0.1, c, 0.04); | 
|  |  | 
|  | ceres_free_problem(problem); | 
|  | } | 
|  |  | 
|  | template <typename T> | 
|  | class ScopedSetValue { | 
|  | public: | 
|  | ScopedSetValue(T* variable, T new_value) | 
|  | : variable_(variable), old_value_(*variable) { | 
|  | *variable = new_value; | 
|  | } | 
|  | ~ScopedSetValue() { *variable_ = old_value_; } | 
|  |  | 
|  | private: | 
|  | T* variable_; | 
|  | T old_value_; | 
|  | }; | 
|  |  | 
|  | TEST(C_API, LossFunctions) { | 
|  | double m = 0.2; | 
|  | double c = 0.03; | 
|  | double* parameter_pointers[] = {&m, &c}; | 
|  | int parameter_sizes[] = {1, 1}; | 
|  |  | 
|  | // Create two outliers, but be careful to leave the data intact. | 
|  | ScopedSetValue<double> outlier1x(&data[12], 2.5); | 
|  | ScopedSetValue<double> outlier1y(&data[13], 1.0e3); | 
|  | ScopedSetValue<double> outlier2x(&data[14], 3.2); | 
|  | ScopedSetValue<double> outlier2y(&data[15], 30e3); | 
|  |  | 
|  | // Create a cauchy cost function, and reuse it many times. | 
|  | void* cauchy_loss_data = ceres_create_cauchy_loss_function_data(5.0); | 
|  |  | 
|  | ceres_problem_t* problem = ceres_create_problem(); | 
|  | for (int i = 0; i < num_observations; ++i) { | 
|  | ceres_problem_add_residual_block( | 
|  | problem, | 
|  | exponential_residual,       // Cost function | 
|  | &data[2 * i],               // Points to the (x,y) measurement | 
|  | ceres_stock_loss_function,  // | 
|  | cauchy_loss_data,           // Loss function user data | 
|  | 1,                          // Number of residuals | 
|  | 2,                          // Number of parameter blocks | 
|  | parameter_sizes, | 
|  | parameter_pointers); | 
|  | } | 
|  |  | 
|  | ceres_solve(problem); | 
|  |  | 
|  | EXPECT_NEAR(0.3, m, 0.02); | 
|  | EXPECT_NEAR(0.1, c, 0.04); | 
|  |  | 
|  | ceres_free_stock_loss_function_data(cauchy_loss_data); | 
|  | ceres_free_problem(problem); | 
|  | } | 
|  |  | 
|  | }  // namespace internal | 
|  | }  // namespace ceres |