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Implements the Birch clustering algorithm.
This node has been automatically generated by wrapping the ``sklearn.cluster.birch.Birch`` class
from the ``sklearn`` library. The wrapped instance can be accessed
through the ``scikits_alg`` attribute.
Every new sample is inserted into the root of the Clustering Feature
Tree. It is then clubbed together with the subcluster that has the
centroid closest to the new sample. This is done recursively till it
ends up at the subcluster of the leaf of the tree has the closest centroid.
Read more in the :ref:`User Guide <birch>`.
**Parameters**
threshold : float, default 0.5
The radius of the subcluster obtained by merging a new sample and the
closest subcluster should be lesser than the threshold. Otherwise a new
subcluster is started.
branching_factor : int, default 50
Maximum number of CF subclusters in each node. If a new samples enters
such that the number of subclusters exceed the branching_factor then
the node has to be split. The corresponding parent also has to be
split and if the number of subclusters in the parent is greater than
the branching factor, then it has to be split recursively.
n_clusters : int, instance of sklearn.cluster model, default None
Number of clusters after the final clustering step, which treats the
subclusters from the leaves as new samples. By default, this final
clustering step is not performed and the subclusters are returned
as they are. If a model is provided, the model is fit treating
the subclusters as new samples and the initial data is mapped to the
label of the closest subcluster. If an int is provided, the model
fit is AgglomerativeClustering with n_clusters set to the int.
compute_labels : bool, default True
Whether or not to compute labels for each fit.
copy : bool, default True
Whether or not to make a copy of the given data. If set to False,
the initial data will be overwritten.
**Attributes**
``root_`` : _CFNode
Root of the CFTree.
``dummy_leaf_`` : _CFNode
Start pointer to all the leaves.
``subcluster_centers_`` : ndarray,
Centroids of all subclusters read directly from the leaves.
``subcluster_labels_`` : ndarray,
Labels assigned to the centroids of the subclusters after
they are clustered globally.
``labels_`` : ndarray, shape (n_samples,)
Array of labels assigned to the input data.
if partial_fit is used instead of fit, they are assigned to the
last batch of data.
**Examples**
>>> from sklearn.cluster import Birch
>>> X = [[0, 1], [0.3, 1], [-0.3, 1], [0, -1], [0.3, -1], [-0.3, -1]]
>>> brc = Birch(branching_factor=50, n_clusters=None, threshold=0.5,
... compute_labels=True)
>>> brc.fit(X)
Birch(branching_factor=50, compute_labels=True, copy=True, n_clusters=None,
threshold=0.5)
>>> brc.predict(X)
array([0, 0, 0, 1, 1, 1])
**References**
* Tian Zhang, Raghu Ramakrishnan, Maron Livny
BIRCH: An efficient data clustering method for large databases.
http://www.cs.sfu.ca/CourseCentral/459/han/papers/zhang96.pdf
* Roberto Perdisci
JBirch - Java implementation of BIRCH clustering algorithm
https://code.google.com/p/jbirch/
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Implements the Birch clustering algorithm.
This node has been automatically generated by wrapping the ``sklearn.cluster.birch.Birch`` class
from the ``sklearn`` library. The wrapped instance can be accessed
through the ``scikits_alg`` attribute.
Every new sample is inserted into the root of the Clustering Feature
Tree. It is then clubbed together with the subcluster that has the
centroid closest to the new sample. This is done recursively till it
ends up at the subcluster of the leaf of the tree has the closest centroid.
Read more in the :ref:`User Guide <birch>`.
**Parameters**
threshold : float, default 0.5
The radius of the subcluster obtained by merging a new sample and the
closest subcluster should be lesser than the threshold. Otherwise a new
subcluster is started.
branching_factor : int, default 50
Maximum number of CF subclusters in each node. If a new samples enters
such that the number of subclusters exceed the branching_factor then
the node has to be split. The corresponding parent also has to be
split and if the number of subclusters in the parent is greater than
the branching factor, then it has to be split recursively.
n_clusters : int, instance of sklearn.cluster model, default None
Number of clusters after the final clustering step, which treats the
subclusters from the leaves as new samples. By default, this final
clustering step is not performed and the subclusters are returned
as they are. If a model is provided, the model is fit treating
the subclusters as new samples and the initial data is mapped to the
label of the closest subcluster. If an int is provided, the model
fit is AgglomerativeClustering with n_clusters set to the int.
compute_labels : bool, default True
Whether or not to compute labels for each fit.
copy : bool, default True
Whether or not to make a copy of the given data. If set to False,
the initial data will be overwritten.
**Attributes**
``root_`` : _CFNode
Root of the CFTree.
``dummy_leaf_`` : _CFNode
Start pointer to all the leaves.
``subcluster_centers_`` : ndarray,
Centroids of all subclusters read directly from the leaves.
``subcluster_labels_`` : ndarray,
Labels assigned to the centroids of the subclusters after
they are clustered globally.
``labels_`` : ndarray, shape (n_samples,)
Array of labels assigned to the input data.
if partial_fit is used instead of fit, they are assigned to the
last batch of data.
**Examples**
>>> from sklearn.cluster import Birch
>>> X = [[0, 1], [0.3, 1], [-0.3, 1], [0, -1], [0.3, -1], [-0.3, -1]]
>>> brc = Birch(branching_factor=50, n_clusters=None, threshold=0.5,
... compute_labels=True)
>>> brc.fit(X)
Birch(branching_factor=50, compute_labels=True, copy=True, n_clusters=None,
threshold=0.5)
>>> brc.predict(X)
array([0, 0, 0, 1, 1, 1])
**References**
* Tian Zhang, Raghu Ramakrishnan, Maron Livny
BIRCH: An efficient data clustering method for large databases.
http://www.cs.sfu.ca/CourseCentral/459/han/papers/zhang96.pdf
* Roberto Perdisci
JBirch - Java implementation of BIRCH clustering algorithm
https://code.google.com/p/jbirch/
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Transform X into subcluster centroids dimension. This node has been automatically generated by wrapping the sklearn.cluster.birch.Birch class from the sklearn library. The wrapped instance can be accessed through the scikits_alg attribute. Each dimension represents the distance from the sample point to each cluster centroid. Parameters
Returns
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Build a CF Tree for the input data. This node has been automatically generated by wrapping the sklearn.cluster.birch.Birch class from the sklearn library. The wrapped instance can be accessed through the scikits_alg attribute. Parameters
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