K-means Clustering¶
Clusters data by trying to separate samples in n groups of equal variance
Documentation
Clusters data by trying to separate samples in n groups of equal variance
Configuration:
n_clusters
The number of clusters to form as well as the number of centroids to generate.
n_init
Number of time the k-means algorithm will be run with different centroid seeds. The final results will be the best output of n_init consecutive runs in terms of inertia.
init
Method for initialization:
‘k-means++’ : selects initial cluster centers for k-mean clustering in a smart way to speed up convergence. See section Notes in k_init for more details.
‘random’: choose n_clusters observations (rows) at random from data for the initial centroids.
If an ndarray is passed, it should be of shape (n_clusters, n_features) and gives the initial centers.
If a callable is passed, it should take arguments X, n_clusters and a random state and return an initialization.
algorithm
K-means algorithm to use. The classical EM-style algorithm is “full”. The “elkan” variation is more efficient on data with well-defined clusters, by using the triangle inequality. However it’s more memory intensive due to the allocation of an extra array of shape (n_samples, n_clusters).
For now “auto” (kept for backward compatibiliy) chooses “elkan” but it might change in the future for a better heuristic.
Changed in version 0.18: Added Elkan algorithm
max_iter
Maximum number of iterations of the k-means algorithm for a single run.
tol
Relative tolerance with regards to Frobenius norm of the difference in the cluster centers of two consecutive iterations to declare convergence.
precompute_distances
Precompute distances (faster but takes more memory).
‘auto’ : do not precompute distances if n_samples * n_clusters > 12 million. This corresponds to about 100MB overhead per job using double precision.
True : always precompute distances.
False : never precompute distances.
Deprecated since version 0.23: ‘precompute_distances’ was deprecated in version 0.22 and will be removed in 0.25. It has no effect.
n_jobs
The number of OpenMP threads to use for the computation. Parallelism is sample-wise on the main cython loop which assigns each sample to its closest center.
None
or-1
means using all processors.Deprecated since version 0.23:
n_jobs
was deprecated in version 0.23 and will be removed in 0.25.random_state
Determines random number generation for centroid initialization. Use an int to make the randomness deterministic. See random_state.
Attributes:
cluster_centers_
Coordinates of cluster centers. If the algorithm stops before fully converging (see
tol
andmax_iter
), these will not be consistent withlabels_
.labels_
Labels of each point
inertia_
Sum of squared distances of samples to their closest cluster center.
Input ports:
- Output ports:
- modelmodel
Model
Definition
Input ports
Output ports
- model
model
Model