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# scipy.cluster.hierarchy.centroid

`scipy.cluster.hierarchy.``centroid`(y)

  Performs centroid/UPGMC linkage.

  See `linkage` for more information on the input matrix, return structure, and algorithm.

  The following are common calling conventions:

  1. `Z = centroid(y)`

     Performs centroid/UPGMC linkage on the condensed distance matrix `y`.

  2. `Z = centroid(X)`

     Performs centroid/UPGMC linkage on the observation matrix `X` using Euclidean distance as the distance metric.

  Parameters: | y : ndarray A condensed distance matrix. A condensed distance matrix is a flat array containing the upper triangular of the distance matrix. This is the form that `pdist` returns. Alternatively, a collection of m observation vectors in n dimensions may be passed as a m by n array.
  Returns: | Z : ndarray A linkage matrix containing the hierarchical clustering. See the `linkage` function documentation for more information on its structure.

  See also

  `linkage`
    for advanced creation of hierarchical clusterings.