faissknn 0.0.3

FAISS implementation of multiclass and multilabel K-Nearest Neighbors Classifiers.

faissknn

faissknn contains implementations for both multiclass and multilabel K-Nearest Neighbors Classifier implementations. The classifiers follow the scikit-learn: fit, predict, and predict_proba methods.

Install

pip install faissknn

This pulls in faiss-cuda-cu128 (Taylor Geospatial's GPU-enabled FAISS wheels for CUDA 12.x) along with numpy and torch. No system CUDA toolkit required — just an NVIDIA driver new enough for CUDA 12 (R525+).

Usage

Multiclass:

from sklearn.datasets import make_classification
from sklearn.model_selection import train_test_split

from faissknn import FaissKNNClassifier

x, y = make_classification()
x_train, x_test, y_train, y_test = train_test_split(x, y)
model = FaissKNNClassifier(
    n_neighbors=5,
    n_classes=None,
    device="cpu"
)
model.fit(x_train, y_train)

y_pred = model.predict(x_test) # (N,)
y_proba = model.predict_proba(x_test) # (N, C)

Multilabel:

from sklearn.datasets import make_classification
from sklearn.model_selection import train_test_split

from faissknn import FaissKNNMultilabelClassifier

x, y = make_multilabel_classification()
x_train, x_test, y_train, y_test = train_test_split(x, y)
model = FaissKNNMultilabelClassifier(
    n_neighbors=5,
    device="cpu"
)
model.fit(x_train, y_train)

y_pred = model.predict(x_test) # (N, C)
y_proba = model.predict_proba(x_test) # (N, C)

GPU/CUDA: faissknn also supports running on the GPU to speed up computation. Simply change the device to cuda or a specific cuda device cuda:0

model = FaissKNNClassifier(
    n_neighbors=5,
    device="cuda"
)
model = FaissKNNClassifier(
    n_neighbors=5,
    device="cuda:0"
)

Cite

If you use faissknn in your research, please considering citing!

@software{isaac_corley_2026_18370748,
  author       = {Isaac Corley},
  title        = {isaaccorley/faissknn: Zenodo Cite},
  month        = jan,
  year         = 2026,
  publisher    = {Zenodo},
  version      = {v0.0.3},
  doi          = {10.5281/zenodo.18370748},
  url          = {https://doi.org/10.5281/zenodo.18370748},
}