April 2021 - Boost - lists.boost.org

[release] Boost 1.76.0 Release Candidate 1
by Marshall Clow 11 Apr '21

11 Apr '21

IMPORTANT NOTE: This will be the last RC posted on BinTray! The first release candidates for the 1.76.0 release are now available at: <https://dl.bintray.com/boostorg/release/1.76.0/source/> The SHA256 checksums are as follows: aaf920e31ae815ff6b55d70a28bb614a6aa6f5cd2f6e4543461d20a4fe39df4e boost_1_76_0_rc1.7z 5dd0c91e1f0f18d452fcaa772d9c30815e449dd4fe99fadf224cca180d98cee3 boost_1_76_0_rc1.zip 5b9844335bc327272030b8050cf417178d26c8abbc64ed7aefc4d818facc1c10 boost_1_76_0_rc1.tar.gz cea1cf7609daf5bb285a625530e8d660dca51816007da7f5eb3f577b685a888d boost_1_76_0_rc1.tar.bz2 As always, the release managers would appreciate it if you download the candidate of your choice and give building it a try. Please report both success and failure, and anything else that is noteworthy. -- The Release managers

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The descriptor does not fit into the select call's fd_set
by George Nistor 10 Apr '21

10 Apr '21

Hi all, I am having a problem with the following error message '' The descriptor does not fit into the select call's fd_set" The setup I have is QNX , VSomeIP lib (socket abstractisation lib) , lib Boost 1.61 (a very old version) I get the error in this lib VSomeIp from the bellow boost call. The call to boost::asio::async_write(3 params) gives the above error message. I have tried to see also on QNX with > pidin -p vsomeip fds How many open file descriptor do I have and I got value 123. As far as I know there is a limitation 1024 of open file descriptors. Could you provide some help? Does the latest boost lib solve this particular case? I appreciate any suggestion, Also please say if any info is missing Thanks George Nistor

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Vector with compile-time polymorphism
by Ivica B 09 Apr '21

09 Apr '21

Hi! I am doing a performance C++ work and there is a data structure that we use and I think it is very useful even for the general public. Here is the description: Currently, I call it *multivector* (I know there is a data structure with the same name, this is a temporary name). It works like this: You specify all the types you want to hold in your multivector: multivector<rectangle, circle, triangle> mvect; Each type is held in a separate std::vector for that type. So in the above case, multivector<rectangle, circle, triangle> consists of three std::vectors: std::vector<rectangle>, std::vector<circle> and std::vector<triangle>. Now, the magic happens when we use templates to process all three vectors at once. Imagine there is a function *draw* for all three types. We can do something like this: mvect.for_each([&](auto& shape) { shape.draw(bitmap); }); The above code generates three for_each loops, for rectangle, circle and triangle. Inside the loops it calls the draw method for each type. There is no dispatching inside the loops, and the loops are really easy for the compiler to optimize (due to their simplicity). Prototype implementation: https://github.com/ibogosavljevic/johnysswlab/blob/master/2021-02-virtualfu… Advantages over std::vector<std::variant>>: * Uses less memory (std::variant uses the amount of memory per element that is big enough to store the biggest type) * Is more optimal: each type generates its own processing loop, there is no dispatching code inside the loop. The compilers vectorized these loops easier. Downsides: * You cannot sort the elements in the whole vectors (even though you can sort them in individual containers) * Code bloat (many types can create a lot of code, this is the case with std::vector<std::variant>> too) Please let me know what you think. Ivica

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GSoC proposal review
by Aditya Tiwari 09 Apr '21

09 Apr '21

Hello all, I'm Aditya Tiwari, a GSoC aspirant. I've submitted my proposal for Boost GIL (generic image library) on GSoC's website under boost. I would be grateful if someone review's my proposal and give me suggestions if needed. I've shared the doc link of my proposal with commenter rights. Thanks and Regards, Aditya Tiwari

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Request to review my proposal
by Pratik Awasthi 08 Apr '21

08 Apr '21

Hello Mentor, I Pratik Awasthi request you to review my GSOC 2021 proposal and do suggest updates https://docs.google.com/document/d/1eeuXx4x2birJXxQChEUnBrLbWTzKd8oc9UspeYU…

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[GSoC'21]Seeking Review of draft Proposal for Project 3: Finalize DataFrame Implementation
by Kowndinya Renduchintala 08 Apr '21

08 Apr '21

Hello everyone! I am Kowndinya Renduchintala, a second Year Undergrad in Computer Science and Engineering Department at Indian Institute of Technology Bombay(IIT Bombay). TO THE COMMUNITY: In short, this project’s end goal is to add to the dataframe implementation of GSoC’19, inspired from R, Python and others. This already has features like constructing a column of data frame, the data frame itself in a couple of ways and also supports operations like select, join etc. My main focus is on adding features that are most desired by a data scientist working with REAL WORLD data and I have added some such possible features in the draft linked below. I have never been into Open Source Software Development before. I would like to make this first attempt of mine a success and I hence seek for advice from anyone willing to spare time, to improve upon my list of deliverables, for establishing the foundation of Boost.uBlas as a new data science library. TO THE MENTOR(David): My progress so far: I have glanced through the GSoC’19 implementation, and referred to some pandas docs to make this draft. I am actually a bit worried because I was too late at completing my Competency test and contacting you, the main reason being a very hectic coursework of mine. The only remaining things are – Modifying the README.md for GitHub Actions Usage and some basic error handling in the code. I have shared the draft in the Google’s portal which also contains a link to my forked repository of ublas, containing my solutions to the competency test. I will also be completing the remaining things(possibly also improve small parts like updating naïve matrix multiplication to Strassen’s) in about 2 days. Also, I want to have a little chat with you as I found out that you were the mentor for this project in 2019 and you might be having some pre-conceived ideas on improving the current implementation, from your previous interaction. Please let me know what you think… Here is the link to my proposal draft : https://drive.google.com/file/d/1cnSrrOWfbteJKlmGxiIY9R5H_-YSkb-n/view? usp=sharing Cheers, Kowndinya

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regarding submission of my first proposal
by amit kumar 08 Apr '21

08 Apr '21

Hello i am Amit kumar. I am currently in third year of undergraduate bachelor's degree program , my field of study is Information Technology.I really curious about open source development and i always support open source software , but i have never contributed to any open source project . I have intermediate level command on c++ and i am doing competitive programming from my first year two and half year from now this is my codeforces <https://codeforces.com/profile/stream_cipher> and codechef <https://www.codechef.com/users/ammitkumar> profile link. I am very beginner to the field of software development but i know some website development . I really want to contribute to the Boost C++ library but i don't have any idea about how to submit the first proposal and how to select the topic on which i should work on please suggest me the path way. waiting for your reply. Thaks :)

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[Boost] [Lambda2] Review starts Monday March 22, 2021 to March 31, 2021
by Joel de Guzman 08 Apr '21

08 Apr '21

The Boost formal review of the Lambda2, authored by Peter Dimov, starts Monday, March 22, 2021 to March 31, 2021 (inclusive). Documentation: https://pdimov.github.io/lambda2/doc/html/lambda2.html Source: https://github.com/pdimov/lambda2/ Lambda2 is a simple, but functional, C++14 lambda library. It takes advantage of the fact that the standard <functional> header already provides placeholders _1, _2, _3, and so on, for use with std::bind, and function objects such as std::plus, std::greater, std::logical_not, and std::bit_xor, corresponding to arithmetic, relational, logical and bitwise operators. Please provide in your review information you think is valuable to understand your choice to ACCEPT or REJECT including Lambda2 as a Boost library. Please be explicit about your decision (ACCEPT or REJECT). Some other questions you might want to consider answering: - What is your evaluation of the design? - What is your evaluation of the implementation? - What is your evaluation of the documentation? - What is your evaluation of the potential usefulness of the library? - Did you try to use the library? With which compiler(s)? Did you have any problems? - How much effort did you put into your evaluation? A glance? A quick reading? In-depth study? - Are you knowledgeable about the problem domain? More information about the Boost Formal Review Process can be found at: http://www.boost.org/community/reviews.html The review is open to anyone who is prepared to put in the work of evaluating and reviewing the library. Prior experience in contributing to Boost reviews is not a requirement. Thank you for your efforts in the Boost community. They are very much appreciated. Peter is often available in the CppLang Slack #boost channel should you require any clarification not covered by the documentation. I am not frequently available in the Slack channel, but I'll certainly pay attention to the discussions. Please don't hesitate to ping me if needed. Cheers, --Joel de Guzman

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FFT proposal for gsoc 2021
by Eduardo Quintana 08 Apr '21

08 Apr '21

Hi Boost community, I've been working on a C++ templated library for Fast Fourier Transforms, https://github.com/Lagrang3/fftx. Templated because some FFT algorithms are algebraic-field independent, eg. you could FFT an array of N matrices provided a Nth matrix-root-of-unity is given. As a result you could have a single algorithm for a variety of underlying, eg. `std::complex<float>`, `std::complex<double>`, `std::complex<long double>`, `boost::math::quaternion`, finite field types (this would yield the "Number theoretic transform" https://cp-algorithms.com/algebra/fft.html#toc-tgt-6) I would like to improve this library during the GSOC 2021, as a proposal for inclusion inside Boost.Math or Boost.Algorithms. Is there anyone interested in supervising this project? Any opinions? Best regards, Eduardo Quintana

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[GSoC 2021] Proposal for Boost.xml
by qiqi tang 07 Apr '21

07 Apr '21

Hello, My name is Fuqi Tang who is a graduate student in China. I am majoring in Software engineering. I want to take part in GSoC 2021 for the Boost.xml project and I will really appreciate it if the community can watch my proposal and give me some advice to improve it. Below is my proposal link https://docs.google.com/document/d/1GYuiVqU8ChaTG2RO2qhQbpF9QSuK5uGRRNDx0M2… Thanks a lot! Regards, Fuqi

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