plotly.figure_factory.create_dendrogram() function in Python

Plotly library of Python can be very useful for data visualization and understanding the data simply and easily.

plotly.figure_factory.create_dendrogram

 A dendrogram is a diagram representing a tree. The figure factory called create_dendrogram performs hierarchical clustering on data and represents the resulting tree. Values on the tree depth axis correspond to distances between clusters.

Syntax: plotly.figure_factory.create_dendrogram(X, orientation=’bottom’, labels=None, colorscale=None, distfun=None, linkagefun=<function <lambda>>, hovertext=None, color_threshold=None)

Parameter:

X ((ndarray)) – it describes the matrix of observations as array of arrays

orientation ((str)) – in this we use ‘top’, ‘right’, ‘bottom’, or ‘left’

labels ((list)) – it describes the list of axis category labels(observation labels)

colorscale ((list)) – it describes the optional colorscale for dendrogram tree

distfun ((function)) – it describes the function to compute the pairwise distance from the observations

linkagefun ((function)) – it describes the function to compute the linkage matrix from the pairwise distances

hovertext ((list[list])) – it describes the list of hovertext for constituent traces of dendrogram clusters

color_threshold ((double)) – it describes the value at which the separation of clusters will be made

Example 1: Simple bottom oriented dendrogram

Python3

from plotly.figure_factory import create_dendrogram
import numpy as np


X = np.random.rand(10,10)
fig = create_dendrogram(X)
fig.show()

Output:

Example 2:  Dendrogram to put on the left of the heatmap

Python3

from plotly.figure_factory import create_dendrogram
import numpy as np


X = np.random.rand(5,5)
names = ['Jack', 'Oxana', 'John', 'Chelsea', 'Mark']

dendro = create_dendrogram(X, orientation='right', labels=names)
dendro.update_layout({'width':700, 'height':500})
dendro.show()

Output: