fast-digits: Integer-to-digits conversion.
Convert an integer to digits and back. This library is both asymptotically (O(n^1.4) vs. O(n^2)) and practically (2x-40x for typical inputs) faster than Data.Digits.
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library fast-digits
library fast-digits:fast-digits-internal
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- fast-digits-0.3.2.0.tar.gz [browse] (Cabal source package)
- Package description (revised from the package)
Note: This package has metadata revisions in the cabal description newer than included in the tarball. To unpack the package including the revisions, use 'cabal get'.
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| Versions [RSS] | 0.1.0.0, 0.2.0.0, 0.2.1.0, 0.3.0.0, 0.3.1.0, 0.3.2.0 |
|---|---|
| Change log | changelog.md |
| Dependencies | base (>=4.15 && <5), fast-digits, ghc-bignum (<1.4) [details] |
| Tested with | ghc ==9.0.2, ghc ==9.2.8, ghc ==9.4.8, ghc ==9.6.7, ghc ==9.8.4, ghc ==9.10.2, ghc ==9.12.2 |
| License | GPL-3.0-only |
| Author | Andrew Lelechenko |
| Maintainer | andrew.lelechenko@gmail.com |
| Revised | Revision 1 made by Bodigrim at 2025-07-15T21:52:11Z |
| Category | Data |
| Home page | https://github.com/Bodigrim/fast-digits |
| Source repo | head: git clone https://github.com/Bodigrim/fast-digits |
| Uploaded | by Bodigrim at 2023-07-29T20:06:59Z |
| Distributions | LTSHaskell:0.3.2.0, Stackage:0.3.2.0 |
| Reverse Dependencies | 2 direct, 0 indirect [details] |
| Downloads | 3674 total (10 in the last 30 days) |
| Rating | (no votes yet) [estimated by Bayesian average] |
| Your Rating | |
| Status | Docs available [build log] Last success reported on 2023-07-29 [all 1 reports] |
Readme for fast-digits-0.3.2.0
[back to package description]fast-digits 
The fastest Haskell library to split integers into digits. It is both asymptotically (O(n1.4) vs. O(n2)) and practically (2x-40x for typical inputs) faster than Data.Digits.
Here are benchmarks for GHC 8.10:
> cabal bench -w ghc-8.10.4 All short 2 FastDigits: OK (3.11s) 12.3 ms ± 701 μs Data.Digits: OK (1.41s) 22.2 ms ± 1.8 ms, 1.81x 10 FastDigits: OK (2.11s) 4.16 ms ± 369 μs Data.Digits: OK (3.74s) 7.40 ms ± 235 μs, 1.78x 100000 FastDigits: OK (4.89s) 1.20 ms ± 69 μs Data.Digits: OK (3.96s) 1.95 ms ± 78 μs, 1.63x 1000000000 FastDigits: OK (4.02s) 985 μs ± 62 μs Data.Digits: OK (3.15s) 1.54 ms ± 70 μs, 1.56x medium 2 FastDigits: OK (3.02s) 1.49 ms ± 66 μs Data.Digits: OK (1.42s) 5.62 ms ± 542 μs, 3.77x 10 FastDigits: OK (2.35s) 571 μs ± 42 μs Data.Digits: OK (1.77s) 1.76 ms ± 152 μs, 3.07x 100000 FastDigits: OK (3.87s) 238 μs ± 19 μs Data.Digits: OK (3.44s) 419 μs ± 23 μs, 1.76x 1000000000 FastDigits: OK (3.05s) 186 μs ± 13 μs Data.Digits: OK (4.42s) 268 μs ± 11 μs, 1.44x long 2 FastDigits: OK (3.75s) 3.60 ms ± 215 μs Data.Digits: OK (1.89s) 125 ms ± 9.6 ms, 34.88x 10 FastDigits: OK (2.30s) 2.24 ms ± 125 μs Data.Digits: OK (2.47s) 39.0 ms ± 2.0 ms, 17.40x 100000 FastDigits: OK (1.93s) 1.88 ms ± 139 μs Data.Digits: OK (4.52s) 8.82 ms ± 533 μs, 4.70x 1000000000 FastDigits: OK (1.77s) 1.71 ms ± 149 μs Data.Digits: OK (1.35s) 5.30 ms ± 482 μs, 3.10x