title: How to make a cluster style dendrogram in bokeh
body: <p>I want to make a cluster style dendrogram in bokeh.
  I like this bokeh dot plot example, but i want to make lines curvy and show a 
  cluster strcuture like this : <a href="http://bl.ocks.org/mbostock/4063570" rel="nofollow noreferrer">http://bl.ocks.org/mbostock/4063570</a></p>
  
  <p>here is code from dot plot from bokeh example:</p>
  
  <pre><code>import numpy as np
  from bokeh.plotting import *
  from bokeh.objects import Range1d
  
  N = 4000
  
  factors = ["a", "b", "c", "d", "e", "f", "g", "h"]
  x0 = [0,0,0,0,0,0,0,0]
  x =  [50, 40, 65, 10, 25, 37, 80, 60]
  
  output_file("categorical.html", title="categorical.py example")
  
  hold()
  
  segment(x0, factors, x, factors, y_range=factors, x_range=Range1d(start=0, end=100), 
          line_width=2, line_color="green", tools="resize,previewsave", title="Dot Plot")
  circle(x, factors, size=15, fill_color="orange", line_color="green", line_width=3, Name="categorical example")
  
  figure()
  
  show()  # open a browser
  </code></pre>
  
  <p><img src="https://i.stack.imgur.com/P2pCK.png" alt="here is the output of bokeh dot plot"></p>
  
  <p>Any suggestion on how to make lines curvy and show the clustering relation like in dendrogram. This picture is shown just to show the idea of straight line with dot. actual target is to show the clustering relation of all lines coming from single point.</p>