1 // Ceres Solver - A fast non-linear least squares minimizer 2 // Copyright 2010, 2011, 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: keir (at) google.com (Keir Mierle) 30 // 31 // Originally by Anton Carver 32 33 #ifndef CERES_INTERNAL_MAP_UTIL_H_ 34 #define CERES_INTERNAL_MAP_UTIL_H_ 35 36 #include <utility> 37 #include "ceres/internal/port.h" 38 39 namespace ceres { 40 41 // Perform a lookup in a map or hash_map, assuming that the key exists. 42 // Crash if it does not. 43 // 44 // This is intended as a replacement for operator[] as an rvalue (for reading) 45 // when the key is guaranteed to exist. 46 // 47 // operator[] is discouraged for several reasons: 48 // * It has a side-effect of inserting missing keys 49 // * It is not thread-safe (even when it is not inserting, it can still 50 // choose to resize the underlying storage) 51 // * It invalidates iterators (when it chooses to resize) 52 // * It default constructs a value object even if it doesn't need to 53 // 54 // This version assumes the key is printable, and includes it in the fatal log 55 // message. 56 template <class Collection> 57 const typename Collection::value_type::second_type& 58 FindOrDie(const Collection& collection, 59 const typename Collection::value_type::first_type& key) { 60 typename Collection::const_iterator it = collection.find(key); 61 CHECK(it != collection.end()) << "Map key not found: " << key; 62 return it->second; 63 } 64 65 // Perform a lookup in a map or hash_map. 66 // If the key is present in the map then the value associated with that 67 // key is returned, otherwise the value passed as a default is returned. 68 template <class Collection> 69 const typename Collection::value_type::second_type& 70 FindWithDefault(const Collection& collection, 71 const typename Collection::value_type::first_type& key, 72 const typename Collection::value_type::second_type& value) { 73 typename Collection::const_iterator it = collection.find(key); 74 if (it == collection.end()) { 75 return value; 76 } 77 return it->second; 78 } 79 80 // Insert a new key and value into a map or hash_map. 81 // If the key is not present in the map the key and value are 82 // inserted, otherwise nothing happens. True indicates that an insert 83 // took place, false indicates the key was already present. 84 template <class Collection> 85 bool InsertIfNotPresent( 86 Collection * const collection, 87 const typename Collection::value_type::first_type& key, 88 const typename Collection::value_type::second_type& value) { 89 pair<typename Collection::iterator, bool> ret = 90 collection->insert(typename Collection::value_type(key, value)); 91 return ret.second; 92 } 93 94 // Perform a lookup in a map or hash_map. 95 // Same as above but the returned pointer is not const and can be used to change 96 // the stored value. 97 template <class Collection> 98 typename Collection::value_type::second_type* 99 FindOrNull(Collection& collection, // NOLINT 100 const typename Collection::value_type::first_type& key) { 101 typename Collection::iterator it = collection.find(key); 102 if (it == collection.end()) { 103 return 0; 104 } 105 return &it->second; 106 } 107 108 // Test to see if a set, map, hash_set or hash_map contains a particular key. 109 // Returns true if the key is in the collection. 110 template <class Collection, class Key> 111 bool ContainsKey(const Collection& collection, const Key& key) { 112 typename Collection::const_iterator it = collection.find(key); 113 return it != collection.end(); 114 } 115 116 // Inserts a new key/value into a map or hash_map. 117 // Dies if the key is already present. 118 template<class Collection> 119 void InsertOrDie(Collection* const collection, 120 const typename Collection::value_type::first_type& key, 121 const typename Collection::value_type::second_type& data) { 122 typedef typename Collection::value_type value_type; 123 CHECK(collection->insert(value_type(key, data)).second) 124 << "duplicate key: " << key; 125 } 126 127 } // namespace ceres 128 129 #endif // CERES_INTERNAL_MAP_UTIL_H_ 130
