1// Ceres Solver - A fast non-linear least squares minimizer 2// Copyright 2012 Google Inc. All rights reserved. 3// http://code.google.com/p/ceres-solver/ 4// 5// Redistribution and use in source and binary forms, with or without 6// modification, are permitted provided that the following conditions are met: 7// 8// * Redistributions of source code must retain the above copyright notice, 9// this list of conditions and the following disclaimer. 10// * Redistributions in binary form must reproduce the above copyright notice, 11// this list of conditions and the following disclaimer in the documentation 12// and/or other materials provided with the distribution. 13// * Neither the name of Google Inc. nor the names of its contributors may be 14// used to endorse or promote products derived from this software without 15// specific prior written permission. 16// 17// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 18// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20// ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE 21// LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 22// CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 23// SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 24// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 25// CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 26// ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 27// POSSIBILITY OF SUCH DAMAGE. 28// 29// Author: sameeragarwal@google.com (Sameer Agarwal) 30// 31// Utility routines for validating arrays. 32// 33// These are useful for detecting two common class of errors. 34// 35// 1. Uninitialized memory - where the user for some reason did not 36// compute part of an array, but the code expects it. 37// 38// 2. Numerical failure while computing the cost/residual/jacobian, 39// e.g. NaN, infinities etc. This is particularly useful since the 40// automatic differentiation code does computations that are not 41// evident to the user and can silently generate hard to debug errors. 42 43#ifndef CERES_INTERNAL_ARRAY_UTILS_H_ 44#define CERES_INTERNAL_ARRAY_UTILS_H_ 45 46#include "ceres/internal/port.h" 47 48namespace ceres { 49namespace internal { 50 51// Fill the array x with an impossible value that the user code is 52// never expected to compute. 53void InvalidateArray(int size, double* x); 54 55// Check if all the entries of the array x are valid, i.e. all the 56// values in the array should be finite and none of them should be 57// equal to the "impossible" value used by InvalidateArray. 58bool IsArrayValid(int size, const double* x); 59 60// If the array contains an invalid value, return the index for it, 61// otherwise return size. 62int FindInvalidValue(const int size, const double* x); 63 64// Utility routine to print an array of doubles to a string. If the 65// array pointer is NULL, it is treated as an array of zeros. 66void AppendArrayToString(const int size, const double* x, string* result); 67 68extern const double kImpossibleValue; 69 70// This routine takes an array of integer values, sorts and uniques 71// them and then maps each value in the array to its position in the 72// sorted+uniqued array. By doing this, if there are are k unique 73// values in the array, each value is replaced by an integer in the 74// range [0, k-1], while preserving their relative order. 75// 76// For example 77// 78// [1 0 3 5 0 1 5] 79// 80// gets mapped to 81// 82// [1 0 2 3 0 1 3] 83void MapValuesToContiguousRange(int size, int* array); 84 85} // namespace internal 86} // namespace ceres 87 88#endif // CERES_INTERNAL_ARRAY_UTILS_H_ 89