It's used here: https://github.com/espruino/EspruinoHub/blob/master/www/rssi.html#L106
So just graphWidget.setData(data); is enough (that does a redraw all by itself)
graphWidget.setData(data);
@Gordon started
Espruino is a JavaScript interpreter for low-power Microcontrollers. This site is both a support community for Espruino and a place to share what you are working on.
It's used here: https://github.com/espruino/EspruinoHub/blob/master/www/rssi.html#L106
So just
graphWidget.setData(data);
is enough (that does a redraw all by itself)