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 #include "glog/logging.h" 39 40 namespace ceres { 41 42 // Perform a lookup in a map or hash_map, assuming that the key exists. 43 // Crash if it does not. 44 // 45 // This is intended as a replacement for operator[] as an rvalue (for reading) 46 // when the key is guaranteed to exist. 47 // 48 // operator[] is discouraged for several reasons: 49 // * It has a side-effect of inserting missing keys 50 // * It is not thread-safe (even when it is not inserting, it can still 51 // choose to resize the underlying storage) 52 // * It invalidates iterators (when it chooses to resize) 53 // * It default constructs a value object even if it doesn't need to 54 // 55 // This version assumes the key is printable, and includes it in the fatal log 56 // message. 57 template <class Collection> 58 const typename Collection::value_type::second_type& 59 FindOrDie(const Collection& collection, 60 const typename Collection::value_type::first_type& key) { 61 typename Collection::const_iterator it = collection.find(key); 62 CHECK(it != collection.end()) << "Map key not found: " << key; 63 return it->second; 64 } 65 66 // Perform a lookup in a map or hash_map. 67 // If the key is present in the map then the value associated with that 68 // key is returned, otherwise the value passed as a default is returned. 69 template <class Collection> 70 const typename Collection::value_type::second_type& 71 FindWithDefault(const Collection& collection, 72 const typename Collection::value_type::first_type& key, 73 const typename Collection::value_type::second_type& value) { 74 typename Collection::const_iterator it = collection.find(key); 75 if (it == collection.end()) { 76 return value; 77 } 78 return it->second; 79 } 80 81 // Insert a new key and value into a map or hash_map. 82 // If the key is not present in the map the key and value are 83 // inserted, otherwise nothing happens. True indicates that an insert 84 // took place, false indicates the key was already present. 85 template <class Collection> 86 bool InsertIfNotPresent( 87 Collection * const collection, 88 const typename Collection::value_type::first_type& key, 89 const typename Collection::value_type::second_type& value) { 90 pair<typename Collection::iterator, bool> ret = 91 collection->insert(typename Collection::value_type(key, value)); 92 return ret.second; 93 } 94 95 // Perform a lookup in a map or hash_map. 96 // Same as above but the returned pointer is not const and can be used to change 97 // the stored value. 98 template <class Collection> 99 typename Collection::value_type::second_type* 100 FindOrNull(Collection& collection, // NOLINT 101 const typename Collection::value_type::first_type& key) { 102 typename Collection::iterator it = collection.find(key); 103 if (it == collection.end()) { 104 return 0; 105 } 106 return &it->second; 107 } 108 109 // Test to see if a set, map, hash_set or hash_map contains a particular key. 110 // Returns true if the key is in the collection. 111 template <class Collection, class Key> 112 bool ContainsKey(const Collection& collection, const Key& key) { 113 typename Collection::const_iterator it = collection.find(key); 114 return it != collection.end(); 115 } 116 117 // Inserts a new key/value into a map or hash_map. 118 // Dies if the key is already present. 119 template<class Collection> 120 void InsertOrDie(Collection* const collection, 121 const typename Collection::value_type::first_type& key, 122 const typename Collection::value_type::second_type& data) { 123 typedef typename Collection::value_type value_type; 124 CHECK(collection->insert(value_type(key, data)).second) 125 << "duplicate key: " << key; 126 } 127 128 } // namespace ceres 129 130 #endif // CERES_INTERNAL_MAP_UTIL_H_ 131
