include/ceres/gradient_checker.h - ceres-solver - Git at Google

 // 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.
 // Copyright 2007 Google Inc. All Rights Reserved.
 //
 // Author: wjr@google.com (William Rucklidge)
 //
 // This file contains a class that exercises a cost function, to make sure
 // that it is computing reasonable derivatives. It compares the Jacobians
 // computed by the cost function with those obtained by finite
 // differences.

 #ifndef CERES_PUBLIC_GRADIENT_CHECKER_H_
 #define CERES_PUBLIC_GRADIENT_CHECKER_H_

 #include <cstddef>
 #include <algorithm>
 #include <vector>

 #include "ceres/internal/eigen.h"
 #include "ceres/internal/fixed_array.h"
 #include "ceres/internal/macros.h"
 #include "ceres/internal/scoped_ptr.h"
 #include "ceres/numeric_diff_cost_function.h"
 #include "glog/logging.h"

 namespace ceres {

 // An object that exercises a cost function, to compare the answers that it
 // gives with derivatives estimated using finite differencing.
 //
 // The only likely usage of this is for testing.
 //
 // How to use: Fill in an array of pointers to parameter blocks for your
 // CostFunction, and then call Probe(). Check that the return value is
 // 'true'. See prober_test.cc for an example.
 //
 // This is templated similarly to NumericDiffCostFunction, as it internally
 // uses that.
 template <typename CostFunctionToProbe,
           int M = 0, int N0 = 0, int N1 = 0, int N2 = 0, int N3 = 0, int N4 = 0>
 class GradientChecker {
  public:
   // Here we stash some results from the probe, for later
   // inspection.
   struct GradientCheckResults {
     // Computed cost.
     Vector cost;

     // The sizes of these matrices are dictated by the cost function's
     // parameter and residual block sizes. Each vector's length will
     // term->parameter_block_sizes().size(), and each matrix is the
     // Jacobian of the residual with respect to the corresponding parameter
     // block.

     // Derivatives as computed by the cost function.
     vector<Matrix> term_jacobians;

     // Derivatives as computed by finite differencing.
     vector<Matrix> finite_difference_jacobians;

     // Infinity-norm of term_jacobians - finite_difference_jacobians.
     double error_jacobians;
   };

   // Checks the Jacobian computed by a cost function.
   //
   // probe_point: The parameter values at which to probe.
   // error_tolerance: A threshold for the infinity-norm difference
   // between the Jacobians. If the Jacobians differ by more than
   // this amount, then the probe fails.
   //
   // term: The cost function to test. Not retained after this call returns.
   //
   // results: On return, the two Jacobians (and other information)
   // will be stored here.  May be NULL.
   //
   // Returns true if no problems are detected and the difference between the
   // Jacobians is less than error_tolerance.
   static bool Probe(double const* const* probe_point,
                     double error_tolerance,
                     CostFunctionToProbe *term,
                     GradientCheckResults* results) {
     CHECK_NOTNULL(probe_point);
     CHECK_NOTNULL(term);
     LOG(INFO) << "-------------------- Starting Probe() --------------------";

     // We need a GradientCheckeresults, whether or not they supplied one.
     internal::scoped_ptr<GradientCheckResults> owned_results;
     if (results == NULL) {
       owned_results.reset(new GradientCheckResults);
       results = owned_results.get();
     }

     // Do a consistency check between the term and the template parameters.
     CHECK_EQ(M, term->num_residuals());
     const int num_residuals = M;
     const vector<int16>& block_sizes = term->parameter_block_sizes();
     const int num_blocks = block_sizes.size();

     CHECK_LE(num_blocks, 5) << "Unable to test functions that take more "
                             << "than 5 parameter blocks";
     if (N0) {
       CHECK_EQ(N0, block_sizes[0]);
       CHECK_GE(num_blocks, 1);
     } else {
       CHECK_LT(num_blocks, 1);
     }
     if (N1) {
       CHECK_EQ(N1, block_sizes[1]);
       CHECK_GE(num_blocks, 2);
     } else {
       CHECK_LT(num_blocks, 2);
     }
     if (N2) {
       CHECK_EQ(N2, block_sizes[2]);
       CHECK_GE(num_blocks, 3);
     } else {
       CHECK_LT(num_blocks, 3);
     }
     if (N3) {
       CHECK_EQ(N3, block_sizes[3]);
       CHECK_GE(num_blocks, 4);
     } else {
       CHECK_LT(num_blocks, 4);
     }
     if (N4) {
       CHECK_EQ(N4, block_sizes[4]);
       CHECK_GE(num_blocks, 5);
     } else {
       CHECK_LT(num_blocks, 5);
     }

     results->term_jacobians.clear();
     results->term_jacobians.resize(num_blocks);
     results->finite_difference_jacobians.clear();
     results->finite_difference_jacobians.resize(num_blocks);

     internal::FixedArray<double*> term_jacobian_pointers(num_blocks);
     internal::FixedArray<double*>
         finite_difference_jacobian_pointers(num_blocks);
     for (int i = 0; i < num_blocks; i++) {
       results->term_jacobians[i].resize(num_residuals, block_sizes[i]);
       term_jacobian_pointers[i] = results->term_jacobians[i].data();
       results->finite_difference_jacobians[i].resize(
           num_residuals, block_sizes[i]);
       finite_difference_jacobian_pointers[i] =
           results->finite_difference_jacobians[i].data();
     }
     results->cost.resize(num_residuals, 1);

     CHECK(term->Evaluate(probe_point, results->cost.data(),
                          term_jacobian_pointers.get()));
     NumericDiffCostFunction<CostFunctionToProbe, CENTRAL, M, N0, N1, N2, N3, N4>
         numeric_term(term, DO_NOT_TAKE_OWNERSHIP);
     CHECK(numeric_term.Evaluate(probe_point, results->cost.data(),
                                 finite_difference_jacobian_pointers.get()));

     results->error_jacobians = 0;
     for (int i = 0; i < num_blocks; i++) {
       Matrix jacobian_difference = results->term_jacobians[i] -
           results->finite_difference_jacobians[i];
       results->error_jacobians =
           std::max(results->error_jacobians,
                    jacobian_difference.lpNorm<Eigen::Infinity>());
     }

     LOG(INFO) << "========== term-computed derivatives ==========";
     for (int i = 0; i < num_blocks; i++) {
       LOG(INFO) << "term_computed block " << i;
       LOG(INFO) << "\n" << results->term_jacobians[i];
     }

     LOG(INFO) << "========== finite-difference derivatives ==========";
     for (int i = 0; i < num_blocks; i++) {
       LOG(INFO) << "finite_difference block " << i;
       LOG(INFO) << "\n" << results->finite_difference_jacobians[i];
     }

     LOG(INFO) << "========== difference ==========";
     for (int i = 0; i < num_blocks; i++) {
       LOG(INFO) << "difference block " << i;
       LOG(INFO) << (results->term_jacobians[i] -
                     results->finite_difference_jacobians[i]);
     }

     LOG(INFO) << "||difference|| = " << results->error_jacobians;

     return results->error_jacobians < error_tolerance;
   }

  private:
   CERES_DISALLOW_IMPLICIT_CONSTRUCTORS(GradientChecker);
 };

 }  // namespace ceres

 #endif  // CERES_PUBLIC_GRADIENT_CHECKER_H_
	// 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.
	// Copyright 2007 Google Inc. All Rights Reserved.
	//
	// Author: wjr@google.com (William Rucklidge)
	//
	// This file contains a class that exercises a cost function, to make sure
	// that it is computing reasonable derivatives. It compares the Jacobians
	// computed by the cost function with those obtained by finite
	// differences.

	#ifndef CERES_PUBLIC_GRADIENT_CHECKER_H_
	#define CERES_PUBLIC_GRADIENT_CHECKER_H_

	#include <cstddef>
	#include <algorithm>
	#include <vector>

	#include "ceres/internal/eigen.h"
	#include "ceres/internal/fixed_array.h"
	#include "ceres/internal/macros.h"
	#include "ceres/internal/scoped_ptr.h"
	#include "ceres/numeric_diff_cost_function.h"
	#include "glog/logging.h"

	namespace ceres {

	// An object that exercises a cost function, to compare the answers that it
	// gives with derivatives estimated using finite differencing.
	//
	// The only likely usage of this is for testing.
	//
	// How to use: Fill in an array of pointers to parameter blocks for your
	// CostFunction, and then call Probe(). Check that the return value is
	// 'true'. See prober_test.cc for an example.
	//
	// This is templated similarly to NumericDiffCostFunction, as it internally
	// uses that.
	template <typename CostFunctionToProbe,
	int M = 0, int N0 = 0, int N1 = 0, int N2 = 0, int N3 = 0, int N4 = 0>
	class GradientChecker {
	public:
	// Here we stash some results from the probe, for later
	// inspection.
	struct GradientCheckResults {
	// Computed cost.
	Vector cost;

	// The sizes of these matrices are dictated by the cost function's
	// parameter and residual block sizes. Each vector's length will
	// term->parameter_block_sizes().size(), and each matrix is the
	// Jacobian of the residual with respect to the corresponding parameter
	// block.

	// Derivatives as computed by the cost function.
	vector<Matrix> term_jacobians;

	// Derivatives as computed by finite differencing.
	vector<Matrix> finite_difference_jacobians;

	// Infinity-norm of term_jacobians - finite_difference_jacobians.
	double error_jacobians;
	};

	// Checks the Jacobian computed by a cost function.
	//
	// probe_point: The parameter values at which to probe.
	// error_tolerance: A threshold for the infinity-norm difference
	// between the Jacobians. If the Jacobians differ by more than
	// this amount, then the probe fails.
	//
	// term: The cost function to test. Not retained after this call returns.
	//
	// results: On return, the two Jacobians (and other information)
	// will be stored here. May be NULL.
	//
	// Returns true if no problems are detected and the difference between the
	// Jacobians is less than error_tolerance.
	static bool Probe(double const* const* probe_point,
	double error_tolerance,
	CostFunctionToProbe *term,
	GradientCheckResults* results) {
	CHECK_NOTNULL(probe_point);
	CHECK_NOTNULL(term);
	LOG(INFO) << "-------------------- Starting Probe() --------------------";

	// We need a GradientCheckeresults, whether or not they supplied one.
	internal::scoped_ptr<GradientCheckResults> owned_results;
	if (results == NULL) {
	owned_results.reset(new GradientCheckResults);
	results = owned_results.get();
	}

	// Do a consistency check between the term and the template parameters.
	CHECK_EQ(M, term->num_residuals());
	const int num_residuals = M;
	const vector<int16>& block_sizes = term->parameter_block_sizes();
	const int num_blocks = block_sizes.size();

	CHECK_LE(num_blocks, 5) << "Unable to test functions that take more "
	<< "than 5 parameter blocks";
	if (N0) {
	CHECK_EQ(N0, block_sizes[0]);
	CHECK_GE(num_blocks, 1);
	} else {
	CHECK_LT(num_blocks, 1);
	}
	if (N1) {
	CHECK_EQ(N1, block_sizes[1]);
	CHECK_GE(num_blocks, 2);
	} else {
	CHECK_LT(num_blocks, 2);
	}
	if (N2) {
	CHECK_EQ(N2, block_sizes[2]);
	CHECK_GE(num_blocks, 3);
	} else {
	CHECK_LT(num_blocks, 3);
	}
	if (N3) {
	CHECK_EQ(N3, block_sizes[3]);
	CHECK_GE(num_blocks, 4);
	} else {
	CHECK_LT(num_blocks, 4);
	}
	if (N4) {
	CHECK_EQ(N4, block_sizes[4]);
	CHECK_GE(num_blocks, 5);
	} else {
	CHECK_LT(num_blocks, 5);
	}

	results->term_jacobians.clear();
	results->term_jacobians.resize(num_blocks);
	results->finite_difference_jacobians.clear();
	results->finite_difference_jacobians.resize(num_blocks);

	internal::FixedArray<double*> term_jacobian_pointers(num_blocks);
	internal::FixedArray<double*>
	finite_difference_jacobian_pointers(num_blocks);
	for (int i = 0; i < num_blocks; i++) {
	results->term_jacobians[i].resize(num_residuals, block_sizes[i]);
	term_jacobian_pointers[i] = results->term_jacobians[i].data();
	results->finite_difference_jacobians[i].resize(
	num_residuals, block_sizes[i]);
	finite_difference_jacobian_pointers[i] =
	results->finite_difference_jacobians[i].data();
	}
	results->cost.resize(num_residuals, 1);

	CHECK(term->Evaluate(probe_point, results->cost.data(),
	term_jacobian_pointers.get()));
	NumericDiffCostFunction<CostFunctionToProbe, CENTRAL, M, N0, N1, N2, N3, N4>
	numeric_term(term, DO_NOT_TAKE_OWNERSHIP);
	CHECK(numeric_term.Evaluate(probe_point, results->cost.data(),
	finite_difference_jacobian_pointers.get()));

	results->error_jacobians = 0;
	for (int i = 0; i < num_blocks; i++) {
	Matrix jacobian_difference = results->term_jacobians[i] -
	results->finite_difference_jacobians[i];
	results->error_jacobians =
	std::max(results->error_jacobians,
	jacobian_difference.lpNorm<Eigen::Infinity>());
	}

	LOG(INFO) << "========== term-computed derivatives ==========";
	for (int i = 0; i < num_blocks; i++) {
	LOG(INFO) << "term_computed block " << i;
	LOG(INFO) << "\n" << results->term_jacobians[i];
	}

	LOG(INFO) << "========== finite-difference derivatives ==========";
	for (int i = 0; i < num_blocks; i++) {
	LOG(INFO) << "finite_difference block " << i;
	LOG(INFO) << "\n" << results->finite_difference_jacobians[i];
	}

	LOG(INFO) << "========== difference ==========";
	for (int i = 0; i < num_blocks; i++) {
	LOG(INFO) << "difference block " << i;
	LOG(INFO) << (results->term_jacobians[i] -
	results->finite_difference_jacobians[i]);
	}

	LOG(INFO) << "\|\|difference\|\| = " << results->error_jacobians;

	return results->error_jacobians < error_tolerance;
	}

	private:
	CERES_DISALLOW_IMPLICIT_CONSTRUCTORS(GradientChecker);
	};

	} // namespace ceres

	#endif // CERES_PUBLIC_GRADIENT_CHECKER_H_