Container is a boost library that provides the same containers as the standard library. Multiindex for short, is a convenient framework that provides, according to your specification, multiple, distinct interfaces to a single underlying container. Boost multiindex container and transaction storage codeguru. Circularbuffer provides a container whose most important property is that it will overwrite the first element in the buffer when a value is added to a full circular buffer. The second parameter determines how many dimensions the array should have. Multiindex features ordered indices, which sort the elements according to.
Furthermore, it provides classes to synchronize access on data which is shared by multiple threads. The manual way of doing this is to have several containers in which objects live, and. Distributed under the boost software license, version 1. The first parameter is the type of the elements to store in the array. It uses variadic templates for stringformat, which for me personally is a huge win.
It is available at amazon, barnes and noble, for kindle, as an epub and as a pdf file. Fit many large or small trees to reweighted versions of the training data. Interprocess in shared memory something that is not always possible with containers from the standard library. For n 10 3 and n 10 4, the results are in agreement with our theoretical analysis, showing a constant factor improvement of 6075% with respect to the stlbased manual simulation. Each access interfacethe main one based on employee id, plus one for sorting by age and another for sorting by nameis specified as a distinct index of the same multi index container, as in listing 2. Im trying to use a boost multiindex container in my simulation.
Multiindex library the heart of bimaps and codeprojectbimap library. Xml to pdf by renderx xep xslfo formatter, visit us at. For example, all containers from this library can be used with boost. More interestingly, copying also recreates the original order in which elements are arranged for every. I also need to modify elements, and i was hoping to confirm the syntax and basic philosophy here too. The object to be modified is identified through an iterator passed as the first parameter to modify. Container is a library that defines the same containers as the standard library. Instantiations are dependent on the following types. Erasing and modifying elements in boost multiindex container. Seems to me like this only applies to the ordered containers, not the. Basic usage of boost multiindex containers 0x2b0x2b. For future travelers, be forewarned that multi index comes with a very heavy compilation cost. Each node consists in the stored object, plus a sequence of headers, depending on the indexes that are used.
But documentation for this module is, lets say, complicated for understanding and especially for quick start, so newbies try to avoid the use of the. The result is a container that mimics the public interface of each of the various stl containers that correspond to your specification. For example, you can interrupt threads created with boost. Multiindex with standard containers in my work on odb i periodically run into a need to define a set container that uses only a subset of data members from a class. Contribute to boostorg container development by creating an account on github.
The boost multi index containers library 1, or boost. Sha1 im using boost multi index for the first time. Methods for improving the performance of weak learners. As a result, a sorted collection with three indices by expiration time, by user id and by transaction id is needed. You can see how a bimap container offers three views over the same collection of. Multiindex provides the member function modify, which operates directly on the container. Indices provide interfaces similar to those of stl containers, making using them familiar. Occasionally i also need to have several such sets for a single class, each containing the same elements but using different subsets of the data members. The allhosts container currently has one functioning index that relies on the hosts id. The necessity in last sorting index came from the requirement to produce reports sorted by user id. Container provides containers in addition to the wellknown containers from the standard library. There is nothing wrong with casting away that const qualifier, it is like saying. Changing elements in a multiindex container with modify. If i introduce an ordered second index that calls on a member function hostgetage, where the age changes over the course of the simulation, is the index always going to be updated when i refer to it.
We also learned that containers can take advantage of idioms such as the sbrm design pattern and rangebased for loops. Multiindex is that it allows you to add an index of type t, where t is different from the stored type. Multiindex is a pretty old library introduced in boost 1. January 2003 trevor hastie, stanford university 2 outline model averaging bagging boosting history of boosting stagewise additive modeling boosting and logistic regression mart boosting and over. Container can make sense if, for example, you need to support a program on multiple platforms and you want to avoid problems caused by implementationspecific differences in the standard library. An assignable class keyfromvalue is said to be a key extractor from a type type if. Nov 23, 2016 in this second part, i would like to talk about the benefits you can get from using boost. Container operations that invalidate any iterators modify the container and cannot be executed concurrently with any operations on existing iterators even if those iterators are not invalidated. For future travelers, be forewarned that multi index comes with a very heavy.
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