linking charts

[Malik Koné]

I have been looking around for the code to help me get started and reproduce a linked chart like this

https://coinmarketcap.com/currencies/bitcoin/

in beta.observablehq.com

Basicaly, I can draw the line chart at the top and the one at the bottom.

I can reproduce the sliding handler on the botton chart.

Problem:

in linking the view at the top to the selected area at the botton. 

I would be gratefull If you showed me the d3 code of working example somewhere.

Thank you