ndarray-npy
Library Featured
.npy and .npz file format support for ndarray
- Downloads
- 560,950
- Dependents
- 99
- Stars
- 71
- Forks
- 28
- Contributors
- 8
- Commits
- 279
- Latest release
- 0.10.0 ·
About
This crate provides support for reading/writing ndarray's ArrayBase type
from/to .npy and .npz files. See the
documentation for more information.
This crate is a work-in-progress. It currently supports only a subset of
.npy header descriptors and supports only primitive fixed-size integer,
primitive floating point, complex floating point, and bool types as the array
element type. You can implement the *Element traits for your own types, but
the next breaking release of this library will probably change those traits.
Future plans include support for:
- Memory-mapped
.npzfiles. (Memory-mapped.npyfiles are already supported.) - More element types (e.g. structs). If you need support for structs before
this is implemented in
ndarray-npy, check out thenpycrate. - Possibly merging this with the
npycrate.
Using with Cargo
To use with the default features:
[dependencies]
ndarray-npy = "0.10.0"
Read the full README
The default feature set includes the compressed_npz feature, which enables
support for uncompresssed and compressed .npz files, and the
num-complex-0_4 feature, which enables support for complex floating point
element types provided by version 0.4 of the num-complex crate. The
compressed_npz feature requires a dependency on the zip crate and a
compression backend crate.
To use without the default features:
[dependencies]
ndarray-npy = { version = "0.10.0", default-features = false }
With default-features = false, ndarray-npy provides support only for .npy
files, not .npz files, and it does not provide support for complex number
elements. If you want support for .npz files or complex number elements, you
can select additional features:
npzenables support for uncompressed.npzfiles. This requires a dependency on thezipcrate.compressed_npzenables support for uncompressed and compressed.npzfiles. This requires a dependency on thezipcrate and a compression backend crate.num-complex-0_4enables support for complex floating point element types provided by version 0.4 of thenum-complexcrate.
For example, you can use just the npz feature:
[dependencies.ndarray-npy]
version = "0.10.0"
default-features = false
features = ["npz"]
Library authors
Library authors should specify their dependency on ndarray-npy like this:
[dependencies.ndarray-npy]
version = "0.10.0"
default-features = false
features = [FEATURES_LIST_HERE]
where the features list is one of the following:
[]if your crate does not depend on.npzfile support["npz"]if your crate depends on.npzfile support but not compression["compressed_npz"]if your crate depends on.npzfile support with compression["num-complex-0_4"]if your crate depends on support for complex element types but not.npzfiles["num-complex-0_4", "npz"]if your crate depends on support for complex element types and.npzfiles but not compression["num-complex-0_4", "compressed_npz"]if your crate depends on support for complex element types and.npzfiles with compression
Releases
See RELEASES.md.
Contributing
Please feel free to create issues and submit PRs. PRs adding more tests would be especially appreciated.
License
Copyright 2018–2025 Jim Turner and ndarray-npy developers
Licensed under the Apache License, Version 2.0, or the MIT license, at your option. You may not use this project except in compliance with those terms.
Compatibility
- Runs on
- GPU support unknown
What shows it
- no dependency or feature matches a backend row
- Native code
- None found
- No native code found
- Python bindings
- No Python binding crate found
- License
- Apache-2.0 OR MIT
Compare with similar projects
Order: strongest tier first, then most downloads, then name, with unmeasured values last. A library counts downloads over 30 days. An app counts binary downloads per release. An app with none counts its crate downloads over 30 days. ML Rust runs this catalogue, so its closest project always gets a row.
| Project | Downloads | Dependents | Stars | Latest release | Runs on (GPU) | Native code | License |
|---|---|---|---|---|---|---|---|
|
.npy and .npz file format support for ndarray |
560,950 downloads over 30 days | 99 | 71 | 0.10.0 | GPU support unknown | No native code found | Apache-2.0 OR MIT |
|
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|
npyz Featured
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467,634 downloads over 30 days | 36 | 33 | 0.9.1 | GPU support unknown | No native code found | MIT |
|
zarrs Featured
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|
vortex Listed
An extensible, state-of-the-art framework for columnar compression, and the fastest FOSS columnar file format. Formerly at @spiraldb, now an Incubation Stage project at LFAI&Data, part of the Linux Foundation. |
98,129 downloads over 30 days | 32 | 3,310 | 0.93.0 | GPU support unknown | Binds native code: zstd-sys | Apache-2.0 |
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netcdf-rust Listed
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|
Model conversion and quantization with no Python: reads SafeTensors, GGUF, TCF and PyTorch state dicts, writes SafeTensors, GGUF and TCF, and quantizes to Q2_K through Q8_0 and IQ4 formats, including Q4_K_M mixes. GPTQ, AWQ, NF4, FP8, EXL2 and ONNX input are not implemented. Python bindings |
23 downloads over 30 days | Not applicable | 0 | 0.2.1 | GPU support unknown | No native code found | Apache-2.0 |
Why FeaturedIt passes every Featured gate.
What it meets
- It has 71 active dependents and 48 new dependents in 365 days. Featured needs 11 active dependents or 9 new dependents in 365 days.
- Active dependents are at 100% of their peak. Featured needs at least 50%.
- Docs are present. The release commit or a manifest ties the crate to the repository.
- No vulnerability advisory stays unpatched past the grace window. At least one version is neither a prerelease nor 0.0.x.
- The last activity is on 1 Nov 2026, 8 days ago. The rules expect an update within 560 days. Dormancy rule
Exact rules: Featured library. The check on applied thresholds version 9.
Every rule outcome, as the check records it
expected-interval: version 0.10.0 base 140, doubled for 560950 downloads per month, doubled for 70.5 active users: E = 560 daysdormancy: last activity 2026-11-01, 8 days ago, E = 560: activefeatured: featured: active_users 70.5, new_adopters 48, former_glory 1
Measurements and sources
Each signal row shows the raw value, its source and the fetch date. The Sources list gathers every distinct source on this page. Movement needs more history.
Sources6 sources
- Description: the crates.io description
- crates.io database dump, fetched
- RustSec advisory database, fetched
- GitHub repository, fetched
- crates.io package, fetched
- GitHub contributors, fetched
Adoption71 active dependents, 48 new dependents in 365 days1 not measured
| Signal | Value | Source | Fetched | Counts |
|---|---|---|---|---|
| Active dependents | 70.5 | crates.io database dump | Yes | |
| New dependents (365 days) | 48 | crates.io database dump | Yes | |
| Peak active dependents | 70 | crates.io database dump | Yes | |
| Active dependents as a share of the peak | 1 | crates.io database dump | Yes | |
| Binary downloads per release | Not measured | Yes |
MaintenanceLatest human commit: 8 days ago3 not measured
| Signal | Value | Source | Fetched | Counts |
|---|---|---|---|---|
| Latest human commit | 2026-11-01 | GitHub repository | Yes | |
| Latest release | 2025-12-15 | crates.io database dump | Yes | |
| First release | 2018-04-22 | crates.io database dump | Yes | |
| Latest version | 0.10.0 | crates.io database dump | Yes | |
| Days the oldest outside issue waits for a reply | 847 | GitHub repository | Yes | |
| Maintainer replies over 365 days | 18 | GitHub repository | Yes | |
| Repository archived | false | GitHub repository | Yes | |
| Repository gone | false | GitHub repository | Yes | |
| Release commit or manifest in the repo | true | crates.io package | Yes | |
| Published docs | true | crates.io database dump | Yes | |
| Latest release fails cargo check | Not measured | Yes | ||
| Build check date | Not measured | Yes | ||
| Build check toolchain | Not measured | Yes |
SecurityUnpatched vulnerabilities: none
| Signal | Value | Source | Fetched | Counts |
|---|---|---|---|---|
| Unpatched vulnerabilities past the grace window | none | RustSec advisory database | Yes | |
| RustSec unmaintained advisory | none | RustSec advisory database | Yes | |
| Deprecation notice | none | crates.io database dump | Yes | |
| Deprecated requirement | none | crates.io database dump | Yes |
Distribution15 releases, 560,950 downloads over 30 days5 not measured
| Signal | Value | Source | Fetched | Counts |
|---|---|---|---|---|
| Releases | 15 | crates.io database dump | Yes | |
| Downloads over 30 days | 560950 | crates.io database dump | Yes | |
| Binary downloads over the last 3 releases | Not measured | Yes | ||
| Homebrew installs on request over 365 days | Not measured | Yes | ||
| Repology repository families | Not measured | Yes | ||
| Docker pull growth over 90 days | Not measured | Yes | ||
| Docker pulls at the growth baseline | Not measured | Yes | ||
| Every version a prerelease | false | crates.io database dump | Yes | |
| Every version 0.0.x | false | crates.io database dump | Yes | |
| Every version yanked | false | crates.io database dump | Yes | |
| Crate deleted from crates.io | false | crates.io database dump | Yes |
Repository71 stars, 28 forks, 8 contributors, 279 commits. Stars alone never qualify a project.
| Signal | Value | Source | Fetched | Counts |
|---|---|---|---|---|
| GitHub stars | 71 | GitHub repository | Yes — one part of the repository route | |
| GitHub forks | 28 | GitHub repository | Yes — one part of the repository route | |
| Contributors with a GitHub account | 8 | GitHub contributors | Yes — one part of the repository route | |
| Commits on the default branch | 279 | GitHub repository | No | |
| Repository's main crate left out of the entry | none | crates.io database dump | Yes |
Facts that never count
| Signal | Value | Source | Fetched | Counts |
|---|---|---|---|---|
| License | Apache-2.0 OR MIT | crates.io database dump | No | |
| Runs on, from listed crates and their direct dependencies | GPU support unknown | crates.io database dump | No | |
| What shows each backend | no dependency or feature matches a backend row | crates.io database dump | No | |
| Native code, from listed crates and their dependencies | No native code found | crates.io database dump | No | |
| Python bindings, from direct dependencies of listed crates | No Python binding crate found | crates.io database dump | No | |
| Crates that depend on a listed crate directly | 99 | crates.io database dump | No |
Corrections and review history
No correction applies to this entry.
Judgments
A judgment enters only through an approved issue and a merged pull request.
No judgment applies to this entry.