Onion
Klib
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Onion | Klib | |
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508 | 23 | |
2,972 | 4,021 | |
6.8% | - | |
9.5 | 4.3 | |
6 days ago | 13 days ago | |
C | C | |
GNU General Public License v3.0 only | MIT License |
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.
Onion
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Orange Pi Neo Coming as a Ryzen 7 and Linux Powered Handheld Device
I've also recently fallen into (reading/watching about) it, and from what I've seen, some of them have really impressive levels of community software support
e.g. https://onionui.github.io
- First Elite Four finish in any Pokemon game in over 12 years
- Miyoo Mini out the box settings
- Miyoo Mini Plus - Saves Problem under Onion v4.2
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Help wanted
OnionOS is your best choice. It's as simple as dropping the files onto your SD card. Then, moving your game files to their respective folders. Here is a video guide. Here is the official page with download and any information you would need. If you're still using the stock card, I'd highly recommend getting a better quality one so that you don't lose all your data again.
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Miyoo Mini Beginner Guide
Download Onion OS to your computer. Onion OS is available from the link below: https://onionui.github.io/
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New release: Onion V4.2.1
Update PixelReader to v0.6 by @Aemiii91 in #1208
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For people sharing SD card between their Miyoo Minis - and encountered problem saving setting with the latest V4 Mini
(Please note that I am using Onion OS V4.2.0-RC, if you are using other version, it may not work.
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I followed the installation instructions of OnionOS and my 256GB SD card is now 108GB. Is this normal?
I followed the instructions from here and used the specialized software. It's a Samsung Pro Evo SD card bought in an official store and the reduction is completely reversible by using the Windows formatter. I don't really mind that much, but am wondering if I didn't noob myself out of twice as much space!
- Please help
Klib
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Factor is faster than Zig
In my example the table stores the hash codes themselves instead of the keys (because the hash function is invertible)
Oh, I see, right. If determining the home bucket is trivial, then the back-shifting method is great. The issue is just that it’s not as much of a general-purpose solution as it may initially seem.
“With a different algorithm (Robin Hood or bidirectional linear probing), the load factor can be kept well over 90% with good performance, as the benchmarks in the same repo demonstrate.”
I’ve seen the 90% claim made several times in literature on Robin Hood hash tables. In my experience, the claim is a bit exaggerated, although I suppose it depends on what our idea of “good performance” is. See these benchmarks, which again go up to a maximum load factor of 0.95 (Although boost and Absl forcibly grow/rehash at 0.85-0.9):
https://strong-starlight-4ea0ed.netlify.app/
Tsl, Martinus, and CC are all Robin Hood tables (https://github.com/Tessil/robin-map, https://github.com/martinus/robin-hood-hashing, and https://github.com/JacksonAllan/CC, respectively). Absl and Boost are the well-known SIMD-based hash tables. Khash (https://github.com/attractivechaos/klib/blob/master/khash.h) is, I think, an ordinary open-addressing table using quadratic probing. Fastmap is a new, yet-to-be-published design that is fundamentally similar to bytell (https://www.youtube.com/watch?v=M2fKMP47slQ) but also incorporates some aspects of the aforementioned SIMD maps (it caches a 4-bit fragment of the hash code to avoid most key comparisons).
As you can see, all the Robin Hood maps spike upwards dramatically as the load factor gets high, becoming as much as 5-6 times slower at 0.95 vs 0.5 in one of the benchmarks (uint64_t key, 256-bit struct value: Total time to erase 1000 existing elements with N elements in map). Only the SIMD maps (with Boost being the better performer) and Fastmap appear mostly immune to load factor in all benchmarks, although the SIMD maps do - I believe - use tombstones for deletion.
I’ve only read briefly about bi-directional linear probing – never experimented with it.
- A simple hash table in C
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So what's the best data structures and algorithms library for C?
It could be that the cost of the function calls, either directly or via a pointer, is drowned out by the cost of the one or more cache misses inevitably invoked with every hash table lookup. But I don't want to say too much before I've finished my benchmarking project and published the results. So let me just caution against laser-focusing on whether the comparator and hash function are/can be inlined. For example stb_ds uses a hardcoded hash function that presumably gets inlined, but in my benchmarking (again, I'll publish it here in coming weeks) shows it to be generally a poor performer (in comparison to not just CC, the current version of which doesn't necessarily inline those functions, but also STC, khash, and the C++ Robin Hood hash tables I tested).
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Generic dynamic array in 60 lines of C
Not an entirely uncommon idea. I've written one.
There's also a well-known one here, in klib: https://github.com/attractivechaos/klib/blob/master/kvec.h
- C_dictionary: A simple dynamically typed and sized hashmap in C - feedback welcome
- Inside boost::unordered_flat_map
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The New Ghostscript PDF Interpreter
Code reuse is achievable by (mis)using the preprocessor system. It is possible to build a somewhat usable API, even for intrusive data structures. (eg. the linux kernel and klib[1])
I do agree that generics are required for modern programming, but for some, the cost of complexity of modern languages (compared to C) and the importance of compatibility seem to outweigh the benefits.
[1]: http://attractivechaos.github.io/klib
- C LIBRARY
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boost::unordered map is a new king of data structures
Unordered hash map shootout CMAP = https://github.com/tylov/STC KMAP = https://github.com/attractivechaos/klib PMAP = https://github.com/greg7mdp/parallel-hashmap FMAP = https://github.com/skarupke/flat_hash_map RMAP = https://github.com/martinus/robin-hood-hashing HMAP = https://github.com/Tessil/hopscotch-map TMAP = https://github.com/Tessil/robin-map UMAP = std::unordered_map Usage: shootout [n-million=40 key-bits=25] Random keys are in range [0, 2^25). Seed = 1656617916: T1: Insert/update random keys: KMAP: time: 1.949, size: 15064129, buckets: 33554432, sum: 165525449561381 CMAP: time: 1.649, size: 15064129, buckets: 22145833, sum: 165525449561381 PMAP: time: 2.434, size: 15064129, buckets: 33554431, sum: 165525449561381 FMAP: time: 2.112, size: 15064129, buckets: 33554432, sum: 165525449561381 RMAP: time: 1.708, size: 15064129, buckets: 33554431, sum: 165525449561381 HMAP: time: 2.054, size: 15064129, buckets: 33554432, sum: 165525449561381 TMAP: time: 1.645, size: 15064129, buckets: 33554432, sum: 165525449561381 UMAP: time: 6.313, size: 15064129, buckets: 31160981, sum: 165525449561381 T2: Insert sequential keys, then remove them in same order: KMAP: time: 1.173, size: 0, buckets: 33554432, erased 20000000 CMAP: time: 1.651, size: 0, buckets: 33218751, erased 20000000 PMAP: time: 3.840, size: 0, buckets: 33554431, erased 20000000 FMAP: time: 1.722, size: 0, buckets: 33554432, erased 20000000 RMAP: time: 2.359, size: 0, buckets: 33554431, erased 20000000 HMAP: time: 0.849, size: 0, buckets: 33554432, erased 20000000 TMAP: time: 0.660, size: 0, buckets: 33554432, erased 20000000 UMAP: time: 2.138, size: 0, buckets: 31160981, erased 20000000 T3: Remove random keys: KMAP: time: 1.973, size: 0, buckets: 33554432, erased 23367671 CMAP: time: 2.020, size: 0, buckets: 33218751, erased 23367671 PMAP: time: 2.940, size: 0, buckets: 33554431, erased 23367671 FMAP: time: 1.147, size: 0, buckets: 33554432, erased 23367671 RMAP: time: 1.941, size: 0, buckets: 33554431, erased 23367671 HMAP: time: 1.135, size: 0, buckets: 33554432, erased 23367671 TMAP: time: 1.064, size: 0, buckets: 33554432, erased 23367671 UMAP: time: 5.632, size: 0, buckets: 31160981, erased 23367671 T4: Iterate random keys: KMAP: time: 0.748, size: 23367671, buckets: 33554432, repeats: 8, sum: 4465059465719680 CMAP: time: 0.627, size: 23367671, buckets: 33218751, repeats: 8, sum: 4465059465719680 PMAP: time: 0.680, size: 23367671, buckets: 33554431, repeats: 8, sum: 4465059465719680 FMAP: time: 0.735, size: 23367671, buckets: 33554432, repeats: 8, sum: 4465059465719680 RMAP: time: 0.464, size: 23367671, buckets: 33554431, repeats: 8, sum: 4465059465719680 HMAP: time: 0.719, size: 23367671, buckets: 33554432, repeats: 8, sum: 4465059465719680 TMAP: time: 0.662, size: 23367671, buckets: 33554432, repeats: 8, sum: 4465059465719680 UMAP: time: 6.168, size: 23367671, buckets: 31160981, repeats: 8, sum: 4465059465719680 T5: Lookup random keys: KMAP: time: 0.943, size: 23367671, buckets: 33554432, lookups: 34235332, found: 29040438 CMAP: time: 0.863, size: 23367671, buckets: 33218751, lookups: 34235332, found: 29040438 PMAP: time: 1.635, size: 23367671, buckets: 33554431, lookups: 34235332, found: 29040438 FMAP: time: 0.969, size: 23367671, buckets: 33554432, lookups: 34235332, found: 29040438 RMAP: time: 1.705, size: 23367671, buckets: 33554431, lookups: 34235332, found: 29040438 HMAP: time: 0.712, size: 23367671, buckets: 33554432, lookups: 34235332, found: 29040438 TMAP: time: 0.584, size: 23367671, buckets: 33554432, lookups: 34235332, found: 29040438 UMAP: time: 1.974, size: 23367671, buckets: 31160981, lookups: 34235332, found: 29040438
- C++ containers but in C
What are some alternatives?
Koriki - SimpleMenu frontend for Miyoo Mini
stb - stb single-file public domain libraries for C/C++
minimal-garlicOS - MiniUI for Garlic OS
Better String - The Better String Library
MiniUI-Legacy-Miyoo-Mini - A custom launcher for the Miyoo Mini
Better Enums - C++ compile-time enum to string, iteration, in a single header file
Ports-Collection - Ports Collection for Onion
ZXing - ZXing ("Zebra Crossing") barcode scanning library for Java, Android
httpp - Micro http server and client written in C++
ZLib - A massively spiffy yet delicately unobtrusive compression library.
Themes - Custom themes for Onion
HTTP Parser - http request/response parser for c