// 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: sameeragarwal@google.com (Sameer Agarwal)
//
// Utility routines for ResidualBlock evaluation.
//
// These are useful for detecting two common class of errors.
//
// 1. Uninitialized memory - where the user for some reason did not
// compute part of a cost/residual/jacobian.
//
// 2. Numerical failure while computing the cost/residual/jacobian,
// e.g. NaN, infinities etc. This is particularly useful since the
// automatic differentiation code does computations that are not
// evident to the user and can silently generate hard to debug errors.

#ifndef CERES_INTERNAL_RESIDUAL_BLOCK_UTILS_H_
#define CERES_INTERNAL_RESIDUAL_BLOCK_UTILS_H_

#include <string>

#include "ceres/internal/export.h"

namespace ceres {
namespace internal {

class ResidualBlock;

// Invalidate cost, resdual and jacobian arrays (if not nullptr).
CERES_NO_EXPORT
void InvalidateEvaluation(const ResidualBlock& block,
                          double* cost,
                          double* residuals,
                          double** jacobians);

// Check if any of the arrays cost, residuals or jacobians contains an
// NaN, return true if it does.
CERES_NO_EXPORT
bool IsEvaluationValid(const ResidualBlock& block,
                       double const* const* parameters,
                       double* cost,
                       double* residuals,
                       double** jacobians);

// Create a string representation of the Residual block containing the
// value of the parameters, residuals and jacobians if present.
// Useful for debugging output.
CERES_NO_EXPORT
std::string EvaluationToString(const ResidualBlock& block,
                               double const* const* parameters,
                               double* cost,
                               double* residuals,
                               double** jacobians);

}  // namespace internal
}  // namespace ceres

#endif  // CERES_INTERNAL_RESIDUAL_BLOCK_UTILS_H_