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K-Means clustering
This node has been automatically generated by wrapping the ``sklearn.cluster.k_means_.KMeans`` class
from the ``sklearn`` library. The wrapped instance can be accessed
through the ``scikits_alg`` attribute.
Read more in the :ref:`User Guide <k_means>`.
**Parameters**
n_clusters : int, optional, default: 8
The number of clusters to form as well as the number of
centroids to generate.
max_iter : int, default: 300
Maximum number of iterations of the k-means algorithm for a
single run.
n_init : int, default: 10
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 : {'k-means++', 'random' or an ndarray}
Method for initialization, defaults to 'k-means++':
'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 k 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.
precompute_distances : {'auto', True, False}
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
tol : float, default: 1e-4
Relative tolerance with regards to inertia to declare convergence
n_jobs : int
The number of jobs to use for the computation. This works by computing
each of the n_init runs in parallel.
If -1 all CPUs are used. If 1 is given, no parallel computing code is
used at all, which is useful for debugging. For n_jobs below -1,
(n_cpus + 1 + n_jobs) are used. Thus for n_jobs = -2, all CPUs but one
are used.
random_state : integer or numpy.RandomState, optional
The generator used to initialize the centers. If an integer is
given, it fixes the seed. Defaults to the global numpy random
number generator.
verbose : int, default 0
Verbosity mode.
copy_x : boolean, default True
When pre-computing distances it is more numerically accurate to center
the data first. If copy_x is True, then the original data is not
modified. If False, the original data is modified, and put back before
the function returns, but small numerical differences may be introduced
by subtracting and then adding the data mean.
**Attributes**
``cluster_centers_`` : array, [n_clusters, n_features]
Coordinates of cluster centers
``labels_`` :
- Labels of each point
``inertia_`` : float
Sum of distances of samples to their closest cluster center.
**Notes**
The k-means problem is solved using Lloyd's algorithm.
The average complexity is given by O(k n T), were n is the number of
samples and T is the number of iteration.
The worst case complexity is given by O(n^(k+2/p)) with
n = n_samples, p = n_features. (D. Arthur and S. Vassilvitskii,
'How slow is the k-means method?' SoCG2006)
In practice, the k-means algorithm is very fast (one of the fastest
clustering algorithms available), but it falls in local minima. That's why
it can be useful to restart it several times.
See also
MiniBatchKMeans:
- Alternative online implementation that does incremental updates
- of the centers positions using mini-batches.
- For large scale learning (say n_samples > 10k) MiniBatchKMeans is
- probably much faster to than the default batch implementation.
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K-Means clustering
This node has been automatically generated by wrapping the ``sklearn.cluster.k_means_.KMeans`` class
from the ``sklearn`` library. The wrapped instance can be accessed
through the ``scikits_alg`` attribute.
Read more in the :ref:`User Guide <k_means>`.
**Parameters**
n_clusters : int, optional, default: 8
The number of clusters to form as well as the number of
centroids to generate.
max_iter : int, default: 300
Maximum number of iterations of the k-means algorithm for a
single run.
n_init : int, default: 10
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 : {'k-means++', 'random' or an ndarray}
Method for initialization, defaults to 'k-means++':
'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 k 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.
precompute_distances : {'auto', True, False}
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
tol : float, default: 1e-4
Relative tolerance with regards to inertia to declare convergence
n_jobs : int
The number of jobs to use for the computation. This works by computing
each of the n_init runs in parallel.
If -1 all CPUs are used. If 1 is given, no parallel computing code is
used at all, which is useful for debugging. For n_jobs below -1,
(n_cpus + 1 + n_jobs) are used. Thus for n_jobs = -2, all CPUs but one
are used.
random_state : integer or numpy.RandomState, optional
The generator used to initialize the centers. If an integer is
given, it fixes the seed. Defaults to the global numpy random
number generator.
verbose : int, default 0
Verbosity mode.
copy_x : boolean, default True
When pre-computing distances it is more numerically accurate to center
the data first. If copy_x is True, then the original data is not
modified. If False, the original data is modified, and put back before
the function returns, but small numerical differences may be introduced
by subtracting and then adding the data mean.
**Attributes**
``cluster_centers_`` : array, [n_clusters, n_features]
Coordinates of cluster centers
``labels_`` :
- Labels of each point
``inertia_`` : float
Sum of distances of samples to their closest cluster center.
**Notes**
The k-means problem is solved using Lloyd's algorithm.
The average complexity is given by O(k n T), were n is the number of
samples and T is the number of iteration.
The worst case complexity is given by O(n^(k+2/p)) with
n = n_samples, p = n_features. (D. Arthur and S. Vassilvitskii,
'How slow is the k-means method?' SoCG2006)
In practice, the k-means algorithm is very fast (one of the fastest
clustering algorithms available), but it falls in local minima. That's why
it can be useful to restart it several times.
See also
MiniBatchKMeans:
- Alternative online implementation that does incremental updates
- of the centers positions using mini-batches.
- For large scale learning (say n_samples > 10k) MiniBatchKMeans is
- probably much faster to than the default batch implementation.
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Transform X to a cluster-distance space. This node has been automatically generated by wrapping the sklearn.cluster.k_means_.KMeans class from the sklearn library. The wrapped instance can be accessed through the scikits_alg attribute. In the new space, each dimension is the distance to the cluster
centers. Note that even if X is sparse, the array returned by
Parameters
Returns
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Compute k-means clustering. This node has been automatically generated by wrapping the sklearn.cluster.k_means_.KMeans class from the sklearn library. The wrapped instance can be accessed through the scikits_alg attribute. Parameters X : array-like or sparse matrix, shape=(n_samples, n_features)
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