scipy.cluster.hierarchy.correspond

scipy.cluster.hierarchy.correspond(Z, Y)

Check for correspondence between linkage and condensed distance matrices.

They must have the same number of original observations for the check to succeed.

This function is useful as a sanity check in algorithms that make extensive use of linkage and distance matrices that must correspond to the same set of original observations.

Parameters

Zarray_like

The linkage matrix to check for correspondence.

Yarray_like

The condensed distance matrix to check for correspondence.

Returns

bbool

A boolean indicating whether the linkage matrix and distance matrix could possibly correspond to one another.

See also

linkage

for a description of what a linkage matrix is.

Examples

>>> from scipy.cluster.hierarchy import ward, correspond
>>> from scipy.spatial.distance import pdist

This method can be used to check if a given linkage matrix Z has been obtained from the application of a cluster method over a dataset X:

>>> X = [[0, 0], [0, 1], [1, 0],
...      [0, 4], [0, 3], [1, 4],
...      [4, 0], [3, 0], [4, 1],
...      [4, 4], [3, 4], [4, 3]]
>>> X_condensed = pdist(X)
>>> Z = ward(X_condensed)

Here, we can compare Z and X (in condensed form):

>>> correspond(Z, X_condensed)
True