I split formateDate into formateDateAxis and formateDateTooltip

The domain here is based on Number type inputs. The range is the effective length of the x axis. The double tilde transforms String into Number.

The domain here is based on Date type inputs. The range is the effective length of the x axis.

Here I have to transform milliseconds to date and then to string, a little bit tricky

I have to convert with Date.parse the formatDateTooltip() argument cause recognizes it as Number instead of a Date object