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This is a note about how to solve "Distance matrix 'X' must be symmetric" when create dendrogram by using scipy.cluster.hierarchy.linkage .
Distance matrix 'X' must be symmetric
At first, checked the .shape of matrix 'X' so that matrix 'X' is symmetric.
Then, because it is a distance matrix, it should be finite number.
In my case, the error occured because it contains infs.
All elements of the condensed distance matrix must be finite, i.e. no NaNs or infs.