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# scipy.cluster.hierarchy.is_valid_linkage

`scipy.cluster.hierarchy.``is_valid_linkage`(Z, warning=False, throw=False, name=None)

  Checks the validity of a linkage matrix.

  A linkage matrix is valid if it is a two dimensional array (type double) with \(n\) rows and 4 columns. The first two columns must contain indices between 0 and \(2n-1\). For a given row `i`, the following two expressions have to hold:

  \[0 \leq \mathtt{Z[i,0]} \leq i+n-1 0 \leq Z[i,1] \leq i+n-1\]

  I.e. a cluster cannot join another cluster unless the cluster being joined has been generated.

  Parameters: | Z : array_like Linkage matrix. warning : bool, optional When True, issues a Python warning if the linkage matrix passed is invalid. throw : bool, optional When True, throws a Python exception if the linkage matrix passed is invalid. name : str, optional This string refers to the variable name of the invalid linkage matrix.
  Returns: | b : bool True if the inconsistency matrix is valid.