|  | // Ceres Solver - A fast non-linear least squares minimizer | 
|  | // Copyright 2010, 2011, 2012 Google Inc. All rights reserved. | 
|  | // http://code.google.com/p/ceres-solver/ | 
|  | // | 
|  | // 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: keir@google.com (Keir Mierle) | 
|  |  | 
|  | #include "ceres/gradient_checking_cost_function.h" | 
|  |  | 
|  | #include <algorithm> | 
|  | #include <cmath> | 
|  | #include <numeric> | 
|  | #include <string> | 
|  | #include <vector> | 
|  |  | 
|  | #include "ceres/cost_function.h" | 
|  | #include "ceres/internal/eigen.h" | 
|  | #include "ceres/internal/scoped_ptr.h" | 
|  | #include "ceres/parameter_block.h" | 
|  | #include "ceres/problem.h" | 
|  | #include "ceres/problem_impl.h" | 
|  | #include "ceres/program.h" | 
|  | #include "ceres/residual_block.h" | 
|  | #include "ceres/runtime_numeric_diff_cost_function.h" | 
|  | #include "ceres/stringprintf.h" | 
|  | #include "ceres/types.h" | 
|  | #include "glog/logging.h" | 
|  |  | 
|  | namespace ceres { | 
|  | namespace internal { | 
|  | namespace { | 
|  |  | 
|  | // True if x and y have an absolute relative difference less than | 
|  | // relative_precision and false otherwise. Stores the relative and absolute | 
|  | // difference in relative/absolute_error if non-NULL. | 
|  | bool IsClose(double x, double y, double relative_precision, | 
|  | double *relative_error, | 
|  | double *absolute_error) { | 
|  | double local_absolute_error; | 
|  | double local_relative_error; | 
|  | if (!absolute_error) { | 
|  | absolute_error = &local_absolute_error; | 
|  | } | 
|  | if (!relative_error) { | 
|  | relative_error = &local_relative_error; | 
|  | } | 
|  | *absolute_error = fabs(x - y); | 
|  | *relative_error = *absolute_error / max(fabs(x), fabs(y)); | 
|  | if (x == 0 || y == 0) { | 
|  | // If x or y is exactly zero, then relative difference doesn't have any | 
|  | // meaning. Take the absolute difference instead. | 
|  | *relative_error = *absolute_error; | 
|  | } | 
|  | return fabs(*relative_error) < fabs(relative_precision); | 
|  | } | 
|  |  | 
|  | class GradientCheckingCostFunction : public CostFunction { | 
|  | public: | 
|  | GradientCheckingCostFunction(const CostFunction* function, | 
|  | double relative_step_size, | 
|  | double relative_precision, | 
|  | const string& extra_info) | 
|  | : function_(function), | 
|  | finite_diff_cost_function_( | 
|  | CreateRuntimeNumericDiffCostFunction(function, | 
|  | CENTRAL, | 
|  | relative_step_size)), | 
|  | relative_precision_(relative_precision), | 
|  | extra_info_(extra_info) { | 
|  | *mutable_parameter_block_sizes() = function->parameter_block_sizes(); | 
|  | set_num_residuals(function->num_residuals()); | 
|  | } | 
|  |  | 
|  | virtual ~GradientCheckingCostFunction() { } | 
|  |  | 
|  | virtual bool Evaluate(double const* const* parameters, | 
|  | double* residuals, | 
|  | double** jacobians) const { | 
|  | if (!jacobians) { | 
|  | // Nothing to check in this case; just forward. | 
|  | return function_->Evaluate(parameters, residuals, NULL); | 
|  | } | 
|  |  | 
|  | int num_residuals = function_->num_residuals(); | 
|  |  | 
|  | // Make space for the jacobians of the two methods. | 
|  | const vector<int16>& block_sizes = function_->parameter_block_sizes(); | 
|  | vector<Matrix> term_jacobians(block_sizes.size()); | 
|  | vector<Matrix> finite_difference_jacobians(block_sizes.size()); | 
|  | vector<double*> term_jacobian_pointers(block_sizes.size()); | 
|  | vector<double*> finite_difference_jacobian_pointers(block_sizes.size()); | 
|  | for (int i = 0; i < block_sizes.size(); i++) { | 
|  | term_jacobians[i].resize(num_residuals, block_sizes[i]); | 
|  | term_jacobian_pointers[i] = term_jacobians[i].data(); | 
|  | finite_difference_jacobians[i].resize(num_residuals, block_sizes[i]); | 
|  | finite_difference_jacobian_pointers[i] = | 
|  | finite_difference_jacobians[i].data(); | 
|  | } | 
|  |  | 
|  | // Evaluate the derivative using the user supplied code. | 
|  | if (!function_->Evaluate(parameters, | 
|  | residuals, | 
|  | &term_jacobian_pointers[0])) { | 
|  | LOG(WARNING) << "Function evaluation failed."; | 
|  | return false; | 
|  | } | 
|  |  | 
|  | // Evaluate the derivative using numeric derivatives. | 
|  | finite_diff_cost_function_->Evaluate( | 
|  | parameters, | 
|  | residuals, | 
|  | &finite_difference_jacobian_pointers[0]); | 
|  |  | 
|  | // See if any elements have relative error larger than the threshold. | 
|  | int num_bad_jacobian_components = 0; | 
|  | double worst_relative_error = 0; | 
|  |  | 
|  | // Accumulate the error message for all the jacobians, since it won't get | 
|  | // output if there are no bad jacobian components. | 
|  | string m; | 
|  | for (int k = 0; k < block_sizes.size(); k++) { | 
|  | // Copy the original jacobian blocks into the jacobians array. | 
|  | if (jacobians[k] != NULL) { | 
|  | MatrixRef(jacobians[k], | 
|  | term_jacobians[k].rows(), | 
|  | term_jacobians[k].cols()) = term_jacobians[k]; | 
|  | } | 
|  |  | 
|  | StringAppendF(&m, | 
|  | "========== " | 
|  | "Jacobian for " "block %d: (%ld by %ld)) " | 
|  | "==========\n", | 
|  | k, | 
|  | static_cast<long>(term_jacobians[k].rows()), | 
|  | static_cast<long>(term_jacobians[k].cols())); | 
|  | // The funny spacing creates appropriately aligned column headers. | 
|  | m += " block  row  col        user dx/dy    num diff dx/dy         " | 
|  | "abs error    relative error         parameter          residual\n"; | 
|  |  | 
|  | for (int i = 0; i < term_jacobians[k].rows(); i++) { | 
|  | for (int j = 0; j < term_jacobians[k].cols(); j++) { | 
|  | double term_jacobian = term_jacobians[k](i, j); | 
|  | double finite_jacobian = finite_difference_jacobians[k](i, j); | 
|  | double relative_error, absolute_error; | 
|  | bool bad_jacobian_entry = | 
|  | !IsClose(term_jacobian, | 
|  | finite_jacobian, | 
|  | relative_precision_, | 
|  | &relative_error, | 
|  | &absolute_error); | 
|  | worst_relative_error = std::max(worst_relative_error, | 
|  | relative_error); | 
|  |  | 
|  | StringAppendF(&m, "%6d %4d %4d %17g %17g %17g %17g %17g %17g", | 
|  | k, i, j, | 
|  | term_jacobian, finite_jacobian, | 
|  | absolute_error, relative_error, | 
|  | parameters[k][j], | 
|  | residuals[i]); | 
|  |  | 
|  | if (bad_jacobian_entry) { | 
|  | num_bad_jacobian_components++; | 
|  | StringAppendF( | 
|  | &m, " ------ (%d,%d,%d) Relative error worse than %g", | 
|  | k, i, j, relative_precision_); | 
|  | } | 
|  | m += "\n"; | 
|  | } | 
|  | } | 
|  | } | 
|  |  | 
|  | // Since there were some bad errors, dump comprehensive debug info. | 
|  | if (num_bad_jacobian_components) { | 
|  | string header = StringPrintf("Detected %d bad jacobian component(s). " | 
|  | "Worst relative error was %g.\n", | 
|  | num_bad_jacobian_components, | 
|  | worst_relative_error); | 
|  | if (!extra_info_.empty()) { | 
|  | header += "Extra info for this residual: " + extra_info_ + "\n"; | 
|  | } | 
|  | LOG(WARNING) << "\n" << header << m; | 
|  | } | 
|  | return true; | 
|  | } | 
|  |  | 
|  | private: | 
|  | const CostFunction* function_; | 
|  | internal::scoped_ptr<CostFunction> finite_diff_cost_function_; | 
|  | double relative_precision_; | 
|  | string extra_info_; | 
|  | }; | 
|  |  | 
|  | }  // namespace | 
|  |  | 
|  | CostFunction *CreateGradientCheckingCostFunction( | 
|  | const CostFunction *cost_function, | 
|  | double relative_step_size, | 
|  | double relative_precision, | 
|  | const string& extra_info) { | 
|  | return new GradientCheckingCostFunction(cost_function, | 
|  | relative_step_size, | 
|  | relative_precision, | 
|  | extra_info); | 
|  | } | 
|  |  | 
|  | ProblemImpl* CreateGradientCheckingProblemImpl(ProblemImpl* problem_impl, | 
|  | double relative_step_size, | 
|  | double relative_precision) { | 
|  | // We create new CostFunctions by wrapping the original CostFunction | 
|  | // in a gradient checking CostFunction. So its okay for the | 
|  | // ProblemImpl to take ownership of it and destroy it. The | 
|  | // LossFunctions and LocalParameterizations are reused and since | 
|  | // they are owned by problem_impl, gradient_checking_problem_impl | 
|  | // should not take ownership of it. | 
|  | Problem::Options gradient_checking_problem_options; | 
|  | gradient_checking_problem_options.cost_function_ownership = TAKE_OWNERSHIP; | 
|  | gradient_checking_problem_options.loss_function_ownership = | 
|  | DO_NOT_TAKE_OWNERSHIP; | 
|  | gradient_checking_problem_options.local_parameterization_ownership = | 
|  | DO_NOT_TAKE_OWNERSHIP; | 
|  |  | 
|  | ProblemImpl* gradient_checking_problem_impl = new ProblemImpl( | 
|  | gradient_checking_problem_options); | 
|  |  | 
|  | Program* program = problem_impl->mutable_program(); | 
|  |  | 
|  | // For every ParameterBlock in problem_impl, create a new parameter | 
|  | // block with the same local parameterization and constancy. | 
|  | const vector<ParameterBlock*>& parameter_blocks = program->parameter_blocks(); | 
|  | for (int i = 0; i < parameter_blocks.size(); ++i) { | 
|  | ParameterBlock* parameter_block = parameter_blocks[i]; | 
|  | gradient_checking_problem_impl->AddParameterBlock( | 
|  | parameter_block->mutable_user_state(), | 
|  | parameter_block->Size(), | 
|  | parameter_block->mutable_local_parameterization()); | 
|  |  | 
|  | if (parameter_block->IsConstant()) { | 
|  | gradient_checking_problem_impl->SetParameterBlockConstant( | 
|  | parameter_block->mutable_user_state()); | 
|  | } | 
|  | } | 
|  |  | 
|  | // For every ResidualBlock in problem_impl, create a new | 
|  | // ResidualBlock by wrapping its CostFunction inside a | 
|  | // GradientCheckingCostFunction. | 
|  | const vector<ResidualBlock*>& residual_blocks = program->residual_blocks(); | 
|  | for (int i = 0; i < residual_blocks.size(); ++i) { | 
|  | ResidualBlock* residual_block = residual_blocks[i]; | 
|  |  | 
|  | // Build a human readable string which identifies the | 
|  | // ResidualBlock. This is used by the GradientCheckingCostFunction | 
|  | // when logging debugging information. | 
|  | string extra_info = StringPrintf( | 
|  | "Residual block id %d; depends on parameters [", i); | 
|  | vector<double*> parameter_blocks; | 
|  | for (int j = 0; j < residual_block->NumParameterBlocks(); ++j) { | 
|  | ParameterBlock* parameter_block = residual_block->parameter_blocks()[j]; | 
|  | parameter_blocks.push_back(parameter_block->mutable_user_state()); | 
|  | StringAppendF(&extra_info, "%p", parameter_block->mutable_user_state()); | 
|  | extra_info += (j < residual_block->NumParameterBlocks() - 1) ? ", " : "]"; | 
|  | } | 
|  |  | 
|  | // Wrap the original CostFunction in a GradientCheckingCostFunction. | 
|  | CostFunction* gradient_checking_cost_function = | 
|  | CreateGradientCheckingCostFunction(residual_block->cost_function(), | 
|  | relative_step_size, | 
|  | relative_precision, | 
|  | extra_info); | 
|  |  | 
|  | // The const_cast is necessary because | 
|  | // ProblemImpl::AddResidualBlock can potentially take ownership of | 
|  | // the LossFunction, but in this case we are guaranteed that this | 
|  | // will not be the case, so this const_cast is harmless. | 
|  | gradient_checking_problem_impl->AddResidualBlock( | 
|  | gradient_checking_cost_function, | 
|  | const_cast<LossFunction*>(residual_block->loss_function()), | 
|  | parameter_blocks); | 
|  | } | 
|  |  | 
|  | return gradient_checking_problem_impl; | 
|  | } | 
|  |  | 
|  |  | 
|  | }  // namespace internal | 
|  | }  // namespace ceres |