https://github.com/lace/vg
Vector-geometry toolbelt for 3D points and vectors
https://github.com/lace/vg
3d-points 3d-vectors geometry linear-algebra numpy shortcuts toolbelt vector vectors
Last synced: 2 months ago
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Vector-geometry toolbelt for 3D points and vectors
- Host: GitHub
- URL: https://github.com/lace/vg
- Owner: lace
- License: bsd-2-clause
- Created: 2018-10-02T23:30:56.000Z (over 6 years ago)
- Default Branch: main
- Last Pushed: 2023-03-01T13:57:31.000Z (over 2 years ago)
- Last Synced: 2025-03-30T15:07:55.986Z (2 months ago)
- Topics: 3d-points, 3d-vectors, geometry, linear-algebra, numpy, shortcuts, toolbelt, vector, vectors
- Language: Python
- Homepage: https://vgpy.dev/
- Size: 337 KB
- Stars: 121
- Watchers: 3
- Forks: 16
- Open Issues: 8
-
Metadata Files:
- Readme: README.md
- Changelog: CHANGELOG.md
- License: LICENSE
Awesome Lists containing this project
README
vg
==
[][pypi]
[][pypi]
[][pypi]
[][coverage]
[][build]
[][black]
A **v**ery **g**ood vector-geometry toolbelt for dealing with 3D points and
vectors. These are simple [NumPy][] operations made readable, built to scale
from prototyping to production.
:book: See the complete documentation: https://vgpy.dev/
[pypi]: https://pypi.org/project/vg/
[coverage]: https://github.com/lace/vg/blob/master/.coveragerc
[build]: https://circleci.com/gh/lace/vg/tree/master
[black]: https://black.readthedocs.io/en/stable/
[lace]: https://github.com/metabolize/lace
[numpy]: https://www.numpy.org/
Examples
--------
Normalize a stack of vectors:
```py
# 😮
vs_norm = vs / np.linalg.norm(vs, axis=1)[:, np.newaxis]
# 😀
vs_norm = vg.normalize(vs)
```
Check for the zero vector:
```py
# 😣
is_almost_zero = np.allclose(v, np.array([0.0, 0.0, 0.0]), rtol=0, atol=1e-05)
# 🤓
is_almost_zero = vg.almost_zero(v, atol=1e-05)
```
Find the major axis of variation (first principal component):
```py
# 😩
mean = np.mean(coords, axis=0)
_, _, pcs = np.linalg.svd(coords - mean)
first_pc = pcs[0]
# 😍
first_pc = vg.major_axis(coords)
```
Compute pairwise angles between two stacks of vectors:
```py
# 😭
dot_products = np.einsum("ij,ij->i", v1s.reshape(-1, 3), v2s.reshape(-1, 3))
cosines = dot_products / np.linalg.norm(v1s, axis=1) / np.linalg.norm(v2s, axis=1)
angles = np.arccos(np.clip(cosines, -1.0, 1.0))
# 🤯
angles = vg.angle(v1s, v2s)
```
Installation
------------
```sh
pip install numpy vg
```
Usage
-----
```py
import numpy as np
import vg
projected = vg.scalar_projection(
np.array([5.0, -3.0, 1.0]),
onto=vg.basis.neg_y
)
```
Development
-----------
First, [install Poetry][].
After cloning the repo, run `./bootstrap.zsh` to initialize a virtual
environment with the project's dependencies.
Subsequently, run `./dev.py install` to update the dependencies.
[install poetry]: https://python-poetry.org/docs/#installation
Acknowledgements
----------------
This collection was developed at Body Labs by [Paul Melnikow][] and extracted
from the Body Labs codebase and open-sourced as part of [blmath][] by [Alex
Weiss][]. blmath was subsequently [forked][fork] by Paul Melnikow and later
the `vx` namespace was broken out into its own package. The project was renamed
to `vg` to resolve a name conflict.
[paul melnikow]: https://github.com/paulmelnikow
[blmath]: https://github.com/bodylabs/blmath
[alex weiss]: https://github.com/algrs
[fork]: https://github.com/metabolize/blmath
License
-------
The project is licensed under the two-clause BSD license.