datasource in charts object

Hi Bokeh,

Firstly I wanted to say that I think Bokeh is really excellent. I have been recently using it in several new projects and have been recommending it to colleagues in the data science community.

I have been using bokeh.charts.HeatMap but would like to get access to the underlying datasource in order to update the labels for the hover tools.

In bokeh.plotting.rect I have access to properties_with_values()[‘renderers’] so I can update the datasource (for using in push_notebook animations).

i.e.

from bokeh.plotting import rect

p = rect(indexes,columns,source = datasource,width=1,height = 1)

ds = p.properties_with_values()[‘renderers’][3]

ds can be used in push_notebook.

But I am unable to find similar functionality in the chart object. Any ideas?

Many thanks

David