fast_float
RapidJSON
Our great sponsors
fast_float | RapidJSON | |
---|---|---|
15 | 15 | |
1,267 | 13,842 | |
1.9% | 0.8% | |
8.8 | 6.1 | |
29 days ago | 5 days ago | |
C++ | C++ | |
Apache License 2.0 | GNU General Public License v3.0 or later |
Stars - the number of stars that a project has on GitHub. Growth - month over month growth in stars.
Activity is a relative number indicating how actively a project is being developed. Recent commits have higher weight than older ones.
For example, an activity of 9.0 indicates that a project is amongst the top 10% of the most actively developed projects that we are tracking.
fast_float
-
Parquet: More than just “Turbo CSV”
> Google put in significant engineering effort into "Ryu", a parsing library for double-precision floating point numbers: https://github.com/ulfjack/ryu
It's not a parsing library, but a printing one, i.e., double -> string. https://github.com/fastfloat/fast_float is a parsing library, i.e., string -> double, not by Google though, but was indeed motivated by parsing JSON fast https://lemire.me/blog/2020/03/10/fast-float-parsing-in-prac...
-
What do number conversions (from string) cost?
For those that don't know, gcc 12.x updated its float parsing logic to something similar to fast_float and it's about 1/6 of the cost presented here (sub 100 in the graph presented here). Strongly suggest using that library or upgrading the compiler if you need the performance.
-
Can sanitizers find the two bugs I wrote in C++?
This makes sense for integers but betware floating point from_chars - libc++ still doesn't implement it and libstdc++ implements it by wrapping locale-dependent libc functions which involves temporarily changing the thread locale and possibly memory allocation to make the passed string 0-terminated. IMO libstdc++'s checkbox "solution" is worse than not implementing it at all - user's are better off using Lemire's API-compatible fast_float implementation [0].
-
Passing Programs To A Stack Machine
I'm a bit stuck on how to do the same thing in c++, due to containers only having a single type. The very inefficient way I'm currently doing it is by passing a program as a vector of strings, and then converting the string constants to doubles with the fast_float library.
-
Parsing can become accidentally quadratic because of sscanf
Just above this comment is a merged PR, which references fast_float library: https://github.com/fastfloat/fast_float
-
Making Rust Float Parsing Fast: libcore Edition
Daniel Lemire @lemire (creator of the algorithm, author of the C++ implementation, and provided constant feedback to help guide the PR).
-
RapidObj v0.1 - A fast, header-only, C++17 library for parsing Wavefront .obj files.
And out of 6,000 lines in the file, at least 3000 are other people's code: earcut for polygon triangulation and fast_float because .obj files typically contain a lot of floating point numbers so it's important to parse them quickly.
-
First release of dragonbox, a fast float-to-string conversion algorithm, is available
How this compares to https://github.com/fastfloat/fast_float ?
-
Why is std::from_chars<float> slow?
I tried to compare it against Daniel Lemire's excellent fast_float library. Fast float took about 180ms for the same program, and all I did was change "std" namespace prefix to "fast_float". It's a factor of 12 difference, at least my machine. I tried MSVC next, and it is a lot better, but it is still ~4 times slower than fast float. AFAIK, clang currently does not implement the feature at all.
-
Iterator invalidation of std::string_view
If you don't mind a 3rd party lib until your stdlib updates, https://github.com/fastfloat/fast_float is best-in-class.
RapidJSON
-
Has anyone embedded a web-UI into a C++ project?
Here's what I did: - I bought a theme that I liked, and used mstch as template engine (matched the theme's template format) - Imported rapidjson for parsing JSON, and used mstch for generating JSON (the JSON I generate is simple enough that I can do this) - Wrote an HTTP handler class for each page that handles the GET and POST requests, generating HTML or JSON depending on the request
-
Is there a good cross-platform (Windows / Linux) C or C++ library for file I/O?
And documentation in most cases is more user-friendly if you will use something like MkDocs(based on Markdown), example http://rapidjson.org/
- What is the best way to store multiple objects of a class as data in C++?
-
How to deserialise json into a C++ struct?
Use RapidJSON https://rapidjson.org/
-
DAW JSON Link v3, a JSON serialization/deserialization library, is released
It seems not super widely used compared to other famous libraries like RapidJSON, nlohmann-json, or simdjson. But it seems the author is very active in developing this project which can mitigate this "lack of community" issue.
-
Is cpp a good language for reading and writing large quantities of JSON files as quickly as possible?
have a look at rapidjson for a a nice simple json framework https://rapidjson.org/ I use it and it's quite fast and as good as anything I used in python.
-
What JSON library do you suggest?
So I just cloned https://github.com/Tencent/rapidjson to see what is the current status. At compile time they check if the C++ compiler supports the "noexcept" keyword, and if so they define RAPIDJSON_NOEXCEPT to be "noexcept". Throughout the implementation, RAPIDJSON_NOEXCEPT is added to quite a few function declarations (about a hundred of them).
- Storing data to be used in simulations.
-
How and where I can learn about Web sockets, APIs, Wrappers to connect with my C++ code?
RapidJSON is also excellent, like fantastic when performance matters. Not sure there's a much faster JSON implementation anywhere, and I've written my own SAX-style parser as a fun, hobby project for C++.
- Can anyone point me to an open-source project that correctly uses allocators?
What are some alternatives?
dragonbox - Reference implementation of Dragonbox in C++
JsonCpp - A C++ library for interacting with JSON.
rapidobj - A fast, header-only, C++17 library for parsing Wavefront .obj files.
json - JSON for Modern C++
C++ Format - A modern formatting library
simdjson - Parsing gigabytes of JSON per second : used by Facebook/Meta Velox, the Node.js runtime, ClickHouse, WatermelonDB, Apache Doris, Milvus, StarRocks
fast-float-rust - Super-fast float parser in Rust (now part of Rust core)
cJSON - Ultralightweight JSON parser in ANSI C
simdutf8 - SIMD-accelerated UTF-8 validation for Rust.
Boost.PropertyTree - Boost.org property_tree module
earcut.hpp - Fast, header-only polygon triangulation
Jansson - C library for encoding, decoding and manipulating JSON data