title: How to set properties of selected/unselected glyphs in bokeh
body: <p>I have a dataset consisting of timeseries of a few observables, and I'd like to use bokeh to look at the phase diagram at different points in the time series. What I want to know is how to change the properties of the selected or unselected glyphs (in this case I'd like to reduce the alpha of the unselected points or change the color of the selected ones).</p>
  
  <p>The code below creates the interface I want in an ipython notebook, and is based on the example in the <a href="http://docs.bokeh.org/en/latest/docs/user_guide/interaction/linking.html" rel="nofollow noreferrer">users guide</a><a href="http://docs.bokeh.org/en/latest/docs/user_guide/interaction/linking.html" rel="nofollow noreferrer">http://docs.bokeh.org/en/latest/docs/user_guide/interaction/linking.html</a>. I can't find any obvious options to set and I'd really rather not have to learn javascript for this one thing.</p>
  
  <pre><code>import numpy as np
  from pandas import DataFrame
  from bokeh.plotting import figure, output_notebook, show, gridplot
  from bokeh.models import ColumnDataSource, widgets
  
  def znzt_ts():#, plot_antisym=False, **kwargs):
      t = np.arange(1000)
      Eu = np.sin(t * np.pi/10) + np.random.random(1000)
      Ez = np.cos(t * np.pi/10) + np.random.random(1000)
      ts = DataFrame({'t': t, 'Eu': Eu, 'Ez': Ez})
      tools = 'box_zoom,pan,reset,save,box_select'
      source = ColumnDataSource(data=ts)
      original_source = ColumnDataSource(data=ts)
  
      p1 = figure(plot_width=300, plot_height=300, 
                  tools=tools)
      p2 = figure(plot_width=300, plot_height=300, tools=tools,)
      p1.circle('t', 'Eu', source=source, size=1)
      p2.circle('Eu', 'Ez', source=source, size=1)
      return gridplot([[p1, p2]])
  
  gp = znzt_ts()
  output_notebook()
  show(gp)
  </code></pre>